INFLATABLE PAD

Abstract

 The present application discloses an inflatable pad, comprising: a first wall; a second wall arranged opposite the first wall and defining a chamber with the first wall; and at least a sponge having a length direction, a width direction and a thickness direction and arranged in the inflatable chamber, the sponge comprising: a base extending in the length direction of the sponge and comprising a first side and a second side in the thickness direction of the sponge; a plurality of first protrusions arranged at intervals on the first side of the base, two adjacent of the plurality of first protrusions defining a first groove, and the plurality of first protrusions fitting with the first wall; and a plurality of second protrusions arranged at intervals on the second side of the base, two adjacent of the plurality of second protrusions defining a second groove, wherein one of the first grooves is aligned with one of the plurality of second protrusions in the thickness direction of the sponge. According to the present application, it is possible to reduce the waste of sponge, simplify the cutting process and improve the cutting efficiency.

Description

Technical Field

[0001] The present application relates to the technical field of inflatable pads, and in particular to an inflatable pad.

Background Art

[0002] With the development of material technology and the increase of social needs, various portable devices are increasingly used in various places, for example, by moving a device from the indoor to the outdoor for use. As a typical example, inflatable pads, which are light in weight and easy to be packaged and stored, have been widely used in recreation and entertainment activities and in outdoor sports.

[0003] An inflatable pad typically comprises a top sheet and a bottom sheet connected to each other to form an inflatable chamber therebetween. In particular, some middle regions of the top sheet and the bottom sheet are welded at multiple locations to form the inflatable chamber, so that the inflatable pad maintains a predetermined shape in an inflated state.

[0004] A tensioning member may be further arranged in the inflatable chamber, connected to both the top sheet and the bottom sheet; in this way the inflatable pad maintains a predetermined shape.

[0005] With a growing demand of inflatable pads both for sports and recreation activities, the variety of choice of inflatable pads has been increased with noticeable structural improvements. In order to improve the suppleness and the touch during use, a sponge is usually provided inside the inflatable pad to replace the tensioning member. However, this sponge may cause an increase in the weight of the whole inflatable pad that can be solved by creating some grooves in the sponge to reduce weight.

[0006] FIG. 1 shows an inflatable pad according to the prior art. The known inflatable pads 10 includes a top sheet 11, a bottom sheet 12, a side sheet 13 and a sponge 20 placed therebetween. The bottom sheet 12 is arranged opposite the top sheet 11 in a thickness direction of the inflatable pad 10 (the Z direction as shown in FIG. 1). The side sheet 13 is arranged between the top sheet 11 and the bottom sheet 12, and a peripheral edge of the top sheet 11 is connected to a peripheral edge of the bottom sheet 12 by means of the side sheet 13, such that the top sheet 11, the bottom sheet 12 and the side sheet 13 jointly define an inflatable chamber 14. Specifically, the peripheral edge of the top sheet 11 is welded to a top edge of the side sheet 13, and the peripheral edge of the bottom sheet 12 is welded to a bottom edge of the side sheet 13. A sponge 20, arranged in the inflatable chamber 14, presents an upper surface fitting with an inner surface of the top sheet 11, and a lower surface fitting with an inner surface of the bottom sheet 12.

[0007] After the pressure of gas (e.g., air) in the inflatable chamber 14 reaches a desired value, the inflatable pad 10 is in an inflated state and maintains a certain shape to be in use. When the inflatable pad 10 has to be stored, the gas in the inflatable chamber 14 is discharged, bringing the inflatable pad 10 in a deflated state greatly reducing its volume.

[0008] As shown in FIG. 2, the sponge 20 is generally rectangular in shape and comprises a base 21, a plurality of upper protrusions 22 and a plurality of lower protrusions 23 extending respectively upwards and downwards from the base 21. An upper groove 24 is provided between two adjacent upper protrusions 22, and a lower groove 25 is provided between two adjacent lower protrusions 23. The plurality of upper protrusions 22 are vertically aligned with the plurality of lower protrusions 23 in a thickness direction of the sponge 20 (the Z direction as shown in FIG. 2). That is, when the upper protrusions 22 are formed on the upper side of the base 21, the lower protrusions 23 are correspondingly formed on the lower side of the base 21, to form a chain of H. As shown in FIG. 2, the upper protrusion 22 and the lower protrusion 23 have equal dimension along the Z direction (considered the thickness of the protrusions), while the size of the upper protrusion 22 and the lower protrusion 23 of the sponge 20 at very two ends along the Y direction (considered the width of the protrusions) are greater than the size (width) of the protrusion in the middle along the Y direction.

[0009] As shown in FIGS. 3 and 4, during the process of cutting the sponge 20, a sponge blank is first cut in a thickness direction (the Z direction as shown in FIG. 3), to obtain a thick sponge block, and then it is cut transversely (the X-Y direction as shown in FIG. 3) according to the set thickness of the sponge and concave-convex structures on upper and lower sides of the sponge to obtain a first target sponge 30 as shown in FIG. 3. After cutting the first target sponge 30, the portions, on the sponge blank, longitudinally aligned with the lower protrusions 23 and the upper protrusions 22 of the first target sponge 30 are recesses. Therefore, it is impossible to obtain a sponge having the same structure as the first target sponge 30 simply by directly cutting it again. Thus, after cutting the first target sponge 30, a piece of waste sponge 50 needs to be cut off from the remaining sponge blank before continuing to cut to obtain a second target sponge 40 having the same structure as the first target sponge 30. However, cutting off the waste sponge 50 not only increases the number of cutting phases, but also causes material waste due to the waste sponge 50, and this leads to an increase of the product cost.

Summary

[0010] An objective of the present application is to provide an inflatable pad, in order to overcome the above problems in the prior art.

[0011] For the inflatable pad provided in the present application, the following technical solution is provided.

[0012] According to a first aspect of the present application, the present application discloses an inflatable pad which comprises a first wall, a second wall, arranged opposite the first wall and defining a first chamber with the first wall. In the first chamber it is arranged at least a first sponge, having a length direction, a width direction and a thickness direction comparable with the chamber in an inflated state. The first sponge comprises a base extending in the length direction of the sponge and presenting a first side and a second side in the thickness direction of the sponge; a plurality of first protrusions arranged at intervals on the first side of the base, two adjacent of the plurality of first protrusions defining a first groove, and the plurality of first protrusions fitting with the first wall; and a plurality of second protrusions arranged at intervals on the second side of the base, two adjacent of the plurality of second protrusions defining a second groove. ,

[0013] One of the first grooves is aligned with one of the plurality of second protrusions in the thickness direction of the sponge, and one of the second grooves is aligned with one of the plurality of first protrusions in the thickness direction of the sponge. The plurality of second protrusions of the first sponge or of a second and lower sponge fits with the second wall.

[0014] Optionally, the inflatable pad may further comprise a side wall, arranged between the first wall and the second wall and surrounding the sponge. The first wall, the second wall and the side wall jointly define the first chamber.

[0015] Preferably, the first chamber may be an inflatable chamber. In the above technical solution, on both sides of the base of the sponge, any of the first protrusions (also referred to as upper protrusions) corresponds to one of the second grooves (also referred to as lower grooves), and any of the first grooves (also referred to as upper grooves) corresponds to one of the second protrusions (also referred to as lower protrusions). In other words, in the present application, the first protrusions and the second protrusions are vertically arranged in a staggered manner and have opposite phases.

[0016] Therefore, during manufacturing of the sponge according to the present application, the sponge blank is first cut in the thickness direction thereof to form an overall outline of the sponge, and then the sponge blank is cut according to the concave-convex structure of the sponge to form a plurality of first grooves and a plurality of first protrusions, so as to form the concave-convex structure on the first or upper side. Afterwards, the sponge blank is transversely cut according to the thickness of the sponge and the concave-convex structure of second protrusions and second grooves, so as to form the concave-convex structure on the second or lower side. At this time, the first sponge is manufactured. Accordingly, the concave-convex structure (i.e., the first protrusions and the first grooves) on the first or upper side of the second sponge adj acent to the first sponge (located below the first sponge) is also formed.

[0017] At this time, is possible to place the sponge between a first and a second wall, which defines a first chamber, obtaining the inflatable pad.

[0018] After the realization of the first sponge, the concave-convex structure (i.e., the second protrusions and the second grooves) on the second or lower side of the second sponge may be formed by only transversely cutting the sponge blank again according to the thickness of the second sponge and the concave-convex structure of second protrusions and second grooves. At this time, the second sponge is manufactured.

[0019] Subsequently, a plurality of sponges of the same structure may be obtained by only transversely cutting the sponge blank multiple times according to the thickness of the sponge to be manufactured and the aforementioned concave-convex structure, and the concave-convex structure (i.e., the first protrusions and the first grooves) on the upper side of the last sponge has been formed.

[0020] Finally, the concave-convex structure on the lower side of the last sponge is generated by only cutting the bottom portion of the sponge blank according to the concave-convex structure of the last sponge to form a plurality of second grooves and a plurality of second protrusions. At this time, all the sponges are manufactured.

[0021] From the foregoing, during the entire sponge manufacturing process, sponge waste is only generated when a concave-convex structure is formed on the first sponge and when a concave-convex structure is formed on the last sponge, and no sponge waste is generated during manufacturing of the remaining sponges, which can thus reduce the waste of sponge. In addition, during the cutting process of two adjacent sponges, the concave-convex structures on the adjacent surfaces of the two adjacent sponges engage with each other and can be in concave-convex fit with each other, such that concave-convex structures of two adjacent sides of the two adjacent sponges may be formed by only taking one cutting according to the predetermined concave-convex structure of the sponge, so that this solution also simplifies the cutting process and improves the cutting efficiency.

[0022] Optionally, the cross-section of the one of the first grooves perpendicular to the width direction of the sponge is the same as the cross-section, perpendicular to the width direction of the sponge, of the second protrusion aligned with the one of the first grooves in the thickness direction of the sponge; and the cross-section of the one of the second groove perpendicular to the width direction of the sponge is the same as the cross-section, perpendicular to the width direction of the sponge, of the first protrusion aligned with the one of the second grooves in the thickness direction of the sponge.

[0023] Optionally, the thickness of the sponge ranges from 4 cm to 15 cm.

[0024] Optionally, the thickness of the first protrusion ranges from 1 cm to 7 cm.

[0025] Optionally, the width of the first groove ranges from 0.5 cm to 8 cm.

[0026] Optionally, a ratio of the width of the first groove or of the second groove to the depth of the first groove or of the second groove ranges from 0.2 to 5.

[0027] Optionally, the sponge is provided with a rounded corner that has a radius ranging from 3 cm to 20 cm.

[0028] Optionally, a ratio of the thickness of the base of the sponge to the thickness of the sponge ranges from 0.07 to 0.87.

[0029] Optionally, the indentation force deflection of the sponge ranges from 55 N to 100 N for 25% IFD, ranges from 80 N to 120 N for 40% IFD, and ranges from 190 N to 230 N for 65% IFD.

[0030] Optionally, a ratio of the indentation force deflection of the sponge for 65% IFD to that for 25% IFD is greater than or equal to 2.0.

[0031] Optionally, the thermal resistance of the sponge ranges from 4 ft²•^oF•h/Btu to 12 ft²•°F•h/Btu.

[0032] Optionally, the density of the sponge ranges from 13 kg/m³ to 48 kg/m³.

[0033] Optionally, all of the plurality of first protrusions have the same cross-section perpendicular to the width direction of the sponge, and all of the plurality of second protrusions have the same cross-section perpendicular to the width direction of the sponge.

[0034] Optionally, the cross-section of the one of the first protrusions perpendicular to the width direction of the sponge is the same as the cross-section of the one of the second protrusions perpendicular to the width direction of the sponge.

[0035] Optionally, the cross-sectional shape of the first protrusion is one of a rectangular shape, a trapezoidal shape, an arc shape and a bowl shape.

[0036] Optionally, at least one of the plurality of first grooves is provided with a first heat insulation sheet at a bottom.

[0037] According to the above technical solution, the first heat insulation sheet can reduce the heat transfer between the ground and the sponge and increase the heat insulation performance (thermal resistance), thereby improving the heat insulation effect of the sponge and improving the user's comfort during use.

[0038] Optionally, at least one of the plurality of second grooves is provided with a second heat insulation sheet at a bottom. Providing the second heat insulation sheet can further improve the heat insulation effect of the sponge.

[0039] Optionally, a plurality of first heat insulation sheets are provided, and the plurality of first heat insulation sheets are formed integrally or arranged independently. When formed integrally, the first heat insulation sheet presents first openings, corresponding to the first protrusions, formed throughout it.

[0040] Optionally, a plurality of second heat insulation sheets are provided, and the plurality of second heat insulation sheets are formed integrally or arranged independently. When formed integrally, the second heat insulation sheet presents second openings, corresponding to the second protrusions, formed throughout it.

[0041] According to a second aspect of the present application, the present application discloses an inflatable pad which further comprises a second sponge having a length direction, a width direction and a thickness direction and arranged in the first chamber. The second sponge comprises a base extending in the length direction of the second sponge and presenting a first side and a second side in the thickness direction of the sponge itself; a plurality of first protrusions arranged at intervals on the first side of the base, two adjacent of the plurality of first protrusions defining a first groove; and a plurality of second protrusions arranged at intervals on the second side of the base, two adjacent of the plurality of second protrusions defining a second groove, and the plurality of second protrusions fitting with the second wall.

[0042] One of the first grooves is aligned with one of the plurality of second protrusions in the thickness direction of the second sponge, and one of the second grooves is aligned with one of the plurality of first protrusions in the thickness direction of the second sponge; and the second protrusions of the first sponge engage with the first grooves of the second sponge, and the second groove of the first sponge engage with the first protrusions of the second sponge. The first sponge being placed upper, while the second sponge being placed lower, below the first sponge.

[0043] Both the first and the second sponge being placed inside the first chamber.

[0044] Optionally, the inflatable pad further includes a heat insulation sheet provided between the first or upper sponge and the second or lower sponge.

[0045] According to a third aspect of the present application, the inflatable pad further comprises a third wall, arranged opposite the second wall so that the second wall is placed between the first wall and the third wall. A surrounding wall is arranged between the third wall and the second wall. The third wall, the second wall and the surrounding wall jointly define a second chamber.

[0046] Preferably, the first chamber and the second chamber are independent of each other.

[0047] Preferably, the second chamber is an inflatable chamber.

[0048] Comparing the inflatable pad disclosed in the present application with the prior art, sponge waste is only generated when a concave-convex structure is formed on the first sponge and when a concave-convex structure is formed on the last sponge, and no sponge waste is generated during manufacturing of the remaining sponges, which can thus reduce the waste of sponge. In addition, during the cutting process of two adjacent sponges, the concave-convex structures on the adjacent surfaces of the two adjacent sponges engage with each other, such that concave-convex structures of two adjacent sides of the two adjacent sponges may be formed by only taking one cutting according to the predetermined concave-convex structure of the sponge, so that this solution also simplifies the cutting process and improves the cutting efficiency.

Brief Description of the Drawings

[0049] Other features and advantages of the present disclosure will be understood from the following embodiments described in detail herein and with reference to the accompanying drawings, in which like reference numerals represent the same or similar components.

FIG. 1 shows a cross-sectional view of an inflatable pad in the prior art;

FIG. 2 shows a schematic perspective view of a sponge in the prior art;

FIG. 3 shows a cutting schematic perspective view of the sponge in the prior art;

FIG. 4 shows a cutting schematic cross-sectional view of the sponge in the prior art;

FIG. 5 shows a schematic perspective view of a sponge according to an embodiment shown and described herein;

FIG. 6 shows a schematic cross-sectional view of a sponge according to an embodiment shown and described herein;

FIG. 7 shows a partial enlarged view of part A in FIG. 6;

FIG. 8a shows a schematic cross-sectional view of a sponge according to another embodiment shown and described herein;

FIG. 8b shows a schematic cross-sectional view of a sponge according to another embodiment shown and described herein;

FIG. 9 shows a cutting schematic cross-sectional view of a sponge according to an embodiment shown and described herein;

FIG. 10 shows a schematic cross-sectional view of a sponge according to another embodiment shown and described herein;

FIG. 11a shows a schematic cross-sectional view of a sponge according to another embodiment shown and described herein;

FIG. 11b shows a schematic cross-sectional view of a sponge according to another embodiment shown and described herein;

FIG. 11c shows a schematic cross-sectional view of a sponge according to another embodiment shown and described herein;

FIG. 11d shows a schematic cross-sectional view of a sponge according to another embodiment shown and described herein;

FIG. 11e shows a schematic cross-sectional view of a sponge according to another embodiment shown and described herein;

FIG. 12 shows a schematic diagram of corner R of a sponge according to an embodiment shown and described herein;

FIG. 13 shows a schematic exploded view of an inflatable pad according to an embodiment shown and described herein;

FIG. 14 shows a schematic exploded view of an inflatable pad according to another embodiment shown and described herein;

FIG. 15 shows a schematic exploded view of an inflatable pad according to another embodiment shown and described herein;

FIG. 16 shows a schematic perspective view of a sponge according to an embodiment shown and described herein;

FIG. 17 shows a schematic perspective view of a sponge according to an embodiment shown and described herein;

FIG. 18 shows a schematic perspective view of a sponge according to an embodiment shown and described herein;

FIG. 19 shows a schematic perspective view of a sponge according to an embodiment shown and described herein;

FIG. 20 shows a schematic cross-sectional view of a sponge assembly according to another embodiment shown and described herein;

FIG. 21 shows a schematic cross-sectional view of a sponge assembly according to another embodiment shown and described herein;

FIG. 22 shows a schematic perspective view of another sponge structure;

FIG. 23 shows a top view of the sponge in FIG. 22;

FIG. 24 shows a cutting schematic perspective view of the sponge in FIG. 22;

FIG. 25 shows a schematic perspective view of a sponge structure according to another embodiment shown and described herein; and

FIG. 26 shows a cutting schematic perspective view of the sponge in FIG. 25.

Detailed Description of Embodiments

[0050] The implementation and application of embodiments of an inflatable pad will be discussed in detail below. However, it should be understood that the embodiments discussed and illustrated herein illustratively described various embodiments, implementations, and applications of the present disclosure, and are not intended to limit the scope of the present disclosure. The following description contains numerous specific details in order to provide deep understanding of the present invention. The present invention may also be implemented without these details. In addition, in order to avoid confusing or obscuring key points of the present invention, some specific details will be omitted in the description. It should be noted that the embodiments and the features thereof in the present invention can be combined with each other without conflicts.

[0051] It should be noted that in the description, like reference numerals and letters denote like items in the following drawings. Therefore, once an item is defined in one of the drawings, it is not necessary to further define and explain the item in the subsequent drawings.

[0052] In the description of the present embodiments, it should be noted that the orientation or position relationships indicated by the terms such as "upper", "lower", "inner", "bottom", "length direction" and "width direction" are based on the orientation or position relationships shown in the drawings or the orientation or position relationships in which a product of the present invention is customarily placed during use, and are only intended to facilitate description of the present invention and simplify the description, rather than indicating or implying that the apparatus or element indicated must have a specific orientation or be configured and operated in the specific orientation, and therefore cannot be construed as limiting the present invention.

[0053] In the description, unless expressly stated or limited otherwise, the terms such as "arrange", "connected", and "connection" should be interpreted broadly. For example, the connection may be a secured connection, a detachable connection, or an integral connection; or may be a mechanical connection or an electrical connection; or may be a direct connection, an indirect connection by means of an intermediate medium, or internal communication between two elements. For those of ordinary skill in the art, the specific meaning of the terms in the description will be understood according to specific circumstances.

[0054] In order to make objectives, technical solutions and advantages of the present invention clearer, the description of the present invention will be further presented in detail below with reference to the drawings.

[0055] As it will be widely presented and described here below, and shown in the attached figures, a preferred embodiment of the present invention provides an inflatable pad 100 comprising a sponge 200 having a structure in which upper protrusions and lower protrusions are arranged in a staggered manner, which can simplify the cutting process, as clearly shown in FIG. 6.

[0056] Deeping into details and as shown for example in FIGS. 13, 14 and 15, the present invention refers to an inflatable pad 100, 600 comprising a first wall 110, 610 (also referred to as a top sheet) and a second wall 120, 620 (also referred to as a bottom sheet) arranged opposite the first wall and defining a first chamber 140, 640 with the first wall. At least a first sponge 200 is arranged in the first chamber 140, 640.

[0057] Preferably, the first chamber 140, 640 is an inflatable chamber. For an easier presentation, in the following the first chamber will be always called first inflatable chamber.

[0058] The inflatable pad 100, 600 as well as the sponge 200 extend in a length direction (the Y direction as shown in FIGS. 5 and 13), in a width direction (the X direction as shown in FIGS. 5 and 13 ) and in a thickness direction (the Z direction as shown in FIGS. 5 and 13). The length direction Y and the width direction X defining a supporting plane for the inflatable pad, while the thickness direction Z defines the height of the inflatable pad.

[0059] The inflatable chamber 140, 640 is advantageously provided with an air valve 180, 680.

[0060] The inflatable pad 100, 600 may further comprise a side wall 130 (FIG. 14) which surrounds the sponge 200 and is provided between the first wall 110, 610 and the second wall 120, 620 to define the first inflatable chamber 140, 640.

[0061] The inflatable pad 600, in another embodiment, may further comprise a third wall 650, arranged opposite the second wall 620 in a thickness direction Z of the inflatable pad (FIG.15), and a surrounding wall 630 provided between the second wall 620 and the third wall 650 to define a second chamber 670. This second chamber 670 is independent from the first chamber 640. Preferably, this second chamber 670 is an inflatable chamber.

[0062] Referring now to FIGS. 5 and 6, a sponge 200 comprises a base 210, a plurality of first protrusions 220 (also referred to as upper protrusions) and a plurality of first grooves 230 (also referred to as upper grooves), and a plurality of second protrusions 240 (also referred to as lower protrusions) and a plurality of second grooves 250 (also referred to as lower grooves). The base 210, extending in a length direction of the sponge 200 (the Y direction as shown in FIG. 5), comprises a first side 211 and a second side 212 which is arranged on the opposite side of the base 210 with respect to the first side 211 in a thickness direction of the sponge 200 (the Z direction as shown in FIG. 5).

[0063] In this embodiment, a plurality of first protrusions 220 are arranged at intervals on the first side 211 of the base 210, and two adjacent first protrusions 220 of the plurality of first protrusions 220 define a first groove 230. The plurality of first protrusions 220 and the plurality of first grooves 230 are arranged on the same side of the base 210 in the thickness direction Z of the sponge 200, and are both arranged on an upper side of the base 210 (the "upper" orientation is shown as the Z direction in FIG. 5). The plurality of first protrusions 220 and the plurality of first grooves 230 are arranged alternately in the length direction L of the sponge 200. That is, one first groove 230 is provided between two adjacent first protrusions 220, and one first protrusion 220 is provided between two adjacent first grooves 230. In other words, except for the end portions, the first protrusion 220 is provided with first grooves 230 on both sides, or the first groove 230 is provided with first protrusions 220 on both sides. As shown in FIGS. 5 and 6, the base 210 of the sponge 200 is provided with the first protrusions 220 on both the first end and the second end of the upper side. Each first groove 230 extends in a width direction of the sponge 200 (the X direction as shown in FIG. 5). Each first protrusion 220 extends in the width direction of the sponge 200 (the X direction as shown in FIG. 5).

[0064] As shown in FIGS. 5 and 6, a plurality of second protrusions 240 are arranged at intervals on the second side 212 of the base 210, and two adjacent second protrusions 240 of the plurality of second protrusions 240 define a second groove 250. The plurality of second protrusions 240 and the plurality of second grooves 250 are arranged on the other side of the base 210 in the thickness direction of the sponge 200, and for example, are both arranged on a lower side of the base 210 (the "lower" orientation as shown in FIG. 5 is shown as the direction opposite to the Z direction). The plurality of second protrusions 240 and the plurality of second grooves 250 are arranged alternately. That is, one second groove 250 is provided between two adjacent second protrusions 240, and one second protrusion 240 is provided between two adjacent second grooves 250. In other words, except for the end portions, the second protrusion 240 is provided with second grooves 250 on both sides, or the second groove 250 is provided with second protrusions 240 on both sides. In this embodiment, as shown in FIGS. 5 and 6, the base 210 of the sponge 200 is provided with the second grooves 250 at both the first end and the second end of the lower side. Each second groove 250 extends in the width direction of the sponge 200 (the X direction as shown in FIG. 5). Each second protrusion 240 extends in the width direction of the sponge 200 (the X direction as shown in FIG. 5).

[0065] In the sponge as shown in FIG. 5, the first protrusions 220 and the first grooves 230 are arranged alternately in a length direction Y of the sponge 200, and the second protrusions 240 and the second grooves 250 are arranged alternately in the length direction Y of the sponge 200. It can be understood that, in some embodiments, the first protrusions 220 and the first grooves 230 may be arranged alternately in a width direction X of the sponge 200, and the second protrusions 240 and the second grooves 250 may be arranged alternately in the width direction X of the sponge 200. The first protrusions 220, the first grooves 230, the second protrusions 240 and the second grooves 250 all extend in the length direction Y of the sponge 200.

[0066] Continuing to refer to FIGS. 5 and 6, each first protrusion 220 is aligned with a corresponding second groove 250 in the thickness direction Z of the sponge 200. Therefore, each first groove 230 is aligned with a corresponding second protrusion 240 in the thickness direction Z of the sponge 200. That is, in the thickness direction Z of the sponge 200, the plurality of first protrusions 220 are positioned corresponding to the plurality of second grooves 250 on a one-to-one basis, and the plurality of first grooves 230 are positioned corresponding to the plurality of second protrusions 240 on a one-to-one basis. When the first protrusions 220 are formed on the upper side of the base 210, the second grooves 250 are correspondingly formed on the lower side of the base 210; or when the first grooves 230 are formed on the upper side of the base 210, the second protrusions 240 are correspondingly formed on the lower side of the base 210. The plurality of first protrusions 220 and the plurality of second protrusions 240 are arranged in the thickness direction Z of the sponge 200 in a staggered manner, that is, have opposite phases. In summary, on both sides of the base 210, any of the first protrusions 220 corresponds to one of the second grooves 250, and any of the first grooves 230 corresponds to one of the second protrusions 240.

[0067] Referring to FIGS. 6 and 7, the cross-section of the first protrusion 220 perpendicular to the width direction X of the sponge 200 (and therefore parallel to the plane YZ) is the same as the cross-section of the second groove 250 perpendicular to the width direction X of the sponge 200 (and therefore considered in the same plane parallel to the plane YZ). In other words, the cross-section of the first protrusion 220 and the cross-section of the second groove 250 have the same shape and equal areas. Similarly, the cross-section of the first groove 230 perpendicular to the width direction X of the sponge 200 (and therefore parallel to the plane YZ) is the same as the cross-section of the second protrusion 240 perpendicular to the width direction X of the sponge 200 (and therefore considered in the same plane parallel to the plane YZ). ). In other words, the cross-section of the second protrusion 240 and the cross-section of the first groove 230 have the same shape and equal areas.

[0068] Referring to FIG.6, the width L1 of the first protrusion 220 is equal to the width L4 of the second groove 250, and the thickness (or height) h1 of the first protrusion 220 is equal to the depth d2 of the second groove 250. The width L3 of the first groove 230 is equal to the width L2 of the second protrusion 240, and the depth d1 of the first groove 230 is equal to the thickness (or height) h2 of the second protrusion 240.

[0069] In this embodiment, the first protrusions 220 and the second grooves 250 are consistent in shape and size, and the first grooves 230 and the second protrusions 240 are consistent in shape and size.

[0070] According to the above description, the sponge 200 has a structure in which upper protrusions and lower protrusions are arranged in a staggered manner, so that the plurality of first protrusions 220 on the first side 211 of the base 210 of the sponge 200 corresponds, in a thickness direction Z, to the plurality of second grooves 250 on the second side 212 of the base 210 of the sponge 200.

[0071] Similarly, the structure of the sponge 200 is such that the plurality of first grooves 230 on the first side 211 of the base 210 of the sponge 200 corresponds, in a thickness direction Z, to the plurality of second protrusions 240 on the second side 212 of the base 210 of the sponge 200.

[0072] Therefore, after the sponge blank is cut according to the concave-convex structure of the sponge 200, two or more identical sponges can be coupled together, by stacking them on top of each other.

[0073] On this aim, and referring for example to FIG.20, the second grooves 250 of one sponge 200, in particular of a first sponge or upper sponge 200U, can be in concave-convex fit with the first protrusions 220 of the sponge 200 below it, also called second sponge or lower sponge 200L. Analogously, and the second protrusions 240 of the upper sponge 200U can be in concave-convex fit with the first grooves 230 of the lower sponge 200L, placed below.

[0074] First sponge or upper sponge 200U and second sponge or lower sponge 200L are identical one another and are identical to the sponge 200. Therefore, in the course of the present description, referring to the sponge 200 or to the first sponge or upper sponge 200U or to the second sponge or lower sponge 200U does not introduce any structural differences. The definition of first or upper sponge 200U or of the second or lower sponge 200L identifies only the position inside the inflatable pad, without any difference in the shape or material or structure of the sponge.

[0075] The two adjacent and superimposed sponges 200 (upper sponge 200U and lower sponge 200L) can completely engage with each other, so that no waste of sponge will occur during cutting.

[0076] In addition, since the upper sponge 200U can in concave-convex fit with the lower sponge 200L, the concave-convex structures of the lower surface of the upper sponge 200U and the upper surface of the lower sponge 200L can be formed simultaneously after taking one cutting on the sponge blank according to the concave-convex structure of the sponge 200, thereby simplifying the cutting process.

[0077] Optionally, referring to FIG. 6, all the first protrusions 220 have the same cross-section perpendicular to the width direction X of the sponge 200, that is, have the same shape and equal areas. Just for an example, the first protrusion 220 may have a rectangular cross-sectional shape. The plurality of first protrusions 220 are arranged at equal intervals in the length direction Y of the sponge 200. That is, the distances between all two adjacent first protrusions 220, i.e., the widths L3 of all the first grooves 230, are equal. The thickness (height) h1 of the first protrusion 220 is equal to the depth d1 of the first groove 230. It can be derived from this that all the first grooves 230 have the same cross-sectional shape and equal areas, and the first groove 230 has a rectangular cross-sectional shape.

[0078] Optionally, referring to FIG. 6, all the second protrusions 240 have the same cross-section along the direction perpendicular to the width direction X of the sponge 200, that is, they have the same shape and equal areas. In the embodiments shown in FIG.6, the second protrusion 240 may have a rectangular cross-sectional shape. The plurality of second protrusions 240 are arranged at equal intervals in the length direction Y of the sponge 200. That is, the distances between all two adjacent second protrusions 240, i.e., the widths L4 of all the second grooves 250, are equal. The thickness (height) h2 of the second protrusion 240 is the depth d2 of the second groove 250. It can be derived from this that all the second grooves 250 have the same cross-sectional shape and equal areas, and the second groove 250 has a rectangular cross-sectional shape.

[0079] In this embodiment, the cross-sectional shape of the first protrusion 220 at either end of the sponge 200 is the same as that of the first protrusions 220 in the middle of the sponge 200. The cross-sectional shape of the second groove 250 at either end of the sponge 200 is the same as that of the second groove 250 in the middle of the sponge 200.

[0080] According to the above technical solution, the first protrusions 220 and the second protrusions 240 may be evenly arranged on the upper and lower sides of the base 210, so that different parts of the user's body can be evenly stressed when the user is lying on the sponge 200.

[0081] In some embodiments, the thickness (height) h1 of the first protrusion 220 may preferably be comprised between 1 cm to 7 cm. For example, h1 may be 1 cm, 6 cm, 7 cm, etc. Further, even more preferably, the thickness (height) h1 of the first protrusion 220 may be comprised between 2 cm to 5 cm. For example, h1 may be 2 cm, 4 cm, 5 cm, etc. Still further preferably, the thickness h1 of the first protrusion 220 may be 3 cm. In some embodiments, the thickness (height) h2 of the second protrusion 240 may preferably be comprised between 1 cm to 7 cm. For example, h2 may be 1 cm, 6 cm, 7 cm, etc. Further, even more preferably, the thickness (height) h2 of the second protrusion 240 may be 2 cm to 5 cm. For example, h2 may be 2 cm, 4 cm, 5 cm, etc. Still further preferably, the thickness h2 of the second protrusion 240 may be 3 cm. Referring to FIG. 6, in some embodiments, the thickness (height) h1 of the first protrusion 220 may be equal to the thickness (height) h2 of the second protrusion 240.

[0082] Referring to FIG. 6, the ratio of the width L3 of the first groove 230 (which is also the distance between the two adjacent first protrusions 220) to the depth d1 of the first groove 230 (which is also the thickness h1 of the first protrusion 220) is denoted as D1, that is,

.

[0083] If the value of D1 is too small, meaning that the ratio of the width L3 of the first groove 230 to the depth d1 of the first groove 230 is small, that is, the first groove 230 is narrow and deep, more cuttings are needed for the same length of sponge 200 (considered therefore along the length direction Y), resulting in excessively high manufacturing costs. If the value of D1 is too large, meaning that the width L3 of the first groove 230 is large and shallow, the area of the surface of the sponge 200 fitting to the upper wall of the inflatable pad is insufficient, and thus the surface of the inflatable pad is uneven when in an inflated state and does not give a sufficient support to a user.

[0084] In some embodiments, D1 may be preferably comprised in a range from 0.2 to 5, that is, 0.2 ≤ D1 ≤ 5. Further, even more preferably, D1 may be comprised in a range from

to 3, that is,

. Still further preferably, D1 may be 1.

[0085] Similarly, continuing to refer to FIG. 6, the ratio of the width L4 of the second groove 250 (which is also the distance between the two adjacent second protrusions 240) to the depth d2 of the second groove 250 (which is also the thickness h2 of the second protrusion 240) is set to D2, that is,

.

[0086] In some embodiments, D2 may be preferably comprised in a range from 0.2 to 5, that is, 0.2 ≤ D2 ≤ 5. Further, even more preferably, D2 may be comprised in a range from

to 3, that is,

. Still further preferably, D2 may be 1.

[0087] Optionally, in some embodiments, the width L3 of the first groove 230 of the sponge 200 may be preferably equal to the depth d1 of the first groove 230. Specifically, the width L3 and the depth d1 of the first groove 230 may both be preferably comprised between 0.5 cm to 8 cm, and for example, may be 0.5 cm, 7 cm, 8 cm, etc. Further, even more preferably, the width L3 and the depth d1 of the first groove 230 may both be comprised between 1 cm to 5 cm, and for example, may be 1 cm, 2 cm, 5 cm, etc. Still further preferably, the width L3 and the depth d1 of the first groove 230 may both be 3 cm.

[0088] Similarly, the width L4 of the second groove 250 may be preferably equal to the depth d2 of the second groove 250. Specifically, the width L4 and the depth d2 of the second groove 250 may both be preferably comprised between 0.5 cm to 8 cm, and for example, may be 0.5 cm, 7 cm, 8 cm, etc. Further, even more preferably, the width L4 and the depth d2 of the second groove 250 may both be comprised between 1 cm to 5 cm, and for example, may be 1 cm, 2 cm, 5 cm, etc. Still further preferably, the width L4 and the depth d2 of the second groove 250 may both be 3 cm.

[0089] Further, when the width L3 of the first groove 230, the depth d1 of the first groove 230, the width L4 of the second groove 250 and the depth d2 of the second groove 250 are all 3 cm, the cross-sectional shape of the first protrusion 220 and the cross-sectional shape of the second groove 250 are both a square with a side length of 3 cm, and the cross-sectional shape of the second protrusion 240 and the cross-sectional shape of the first groove 230 are both a square with a side length of 3 cm.

[0090] The thickness of the sponge 200 is related to the heat insulation effect of the sponge 200, and is thus associated with the heat insulation effect of the inflatable pad including the sponge 200. The heat insulation effect may be expressed by the thermal resistance (R value). The higher the thermal resistance, the better the heat insulation effect.

[0091] However, in the prior art shown in FIG. 1, the effective thickness of a portion of the sponge 20 (i.e., the thickness that actually achieves the heat insulation effect) is equal to the thickness h' of the base 21, and the effective thickness of the other portion of the sponge 20 is equal to the sum of the thickness h' of the base 21, the thickness h1' of the upper protrusion 22 and the thickness h2' of the lower protrusion 23. The region with the thickness h' is thin and thus has a poor heat insulation effect, thus reducing the heat insulation performance of the entire sponge.

[0092] Referring to FIG. 6, in this embodiment, in some regions, the effective thickness of the sponge 200 is equal to the sum of the thickness h1 of the first protrusion 220 and the thickness h of the base 210; and in other regions, the effective thickness of the sponge 200 is also equal to the sum of the thickness h2 of the second protrusion 240 and the thickness h of the base 210. Since the thickness h1 of the first protrusion 220 is equal to the thickness h2 of the second protrusion 240, the regions of the sponge 200 according to the present application are more uniform in thickness, and even as shown in FIG. 6 the regions of the sponge 200 have approximately equal thicknesses. Therefore, in this embodiment, the sponge 200 has a higher thermal resistance, that is, the sponge 200 has better overall heat insulation performance.

[0093] Specifically, in some embodiments, the thickness (height) h of the base 210 may be preferably comprised between 1 cm to 13 cm. For example, h may be 1 cm, 5 cm, 13 cm, etc. Further, even more preferably, the thickness (height) h of the base 210 may be preferably comprised between 2 cm to 7 cm. For example, h may be 2 cm, 6 cm, 7 cm, etc. Still further preferably, the thickness h of the base 210 may be 5 cm.

[0094] Specifically, as shown in FIG. 6, the overall thickness H of the sponge 200 proposed by the embodiment of the present application may preferably be comprised between 4 cm to 15 cm, and for example, may be 4 cm, 8 cm, 15 cm, etc. Further, even more preferably, the overall thickness H of the sponge 200 may be comprised between 6 cm to 12 cm, and for example, may be 6 cm, 9 cm, 12 cm, etc. Still further preferably, the overall thickness H of the sponge 200 may be 11 cm.

[0095] The thickness h of the base 210 is associated with the heat insulation effect of the sponge 200. The thicker the base 210 is, the better the heat insulation effect. The ratio of the thickness h of the base 210 to the overall thickness H of the sponge 200 is D3, that is,

.

[0096] If the value of D3 is too large, referring to FIG. 8a, it is indicated that the thickness h of the base 210 is high, and the thickness h1 of the first protrusion 220 is small. Thus, although the heat insulation effect of the sponge 200 can be improved, when the top sheet 110 is hot-pressed onto the sponge 200 by means of a heat press machine during the manufacturing process, the sponge 200 is deformed due to the pressure of the equipment to cause the top sheet 110 to fit with the first groove 230, thus resulting in unaccepted products. If the value of D3 is too small, referring to FIG. 8b, it is indicated that the thickness h of the base 210 is small compared to the thickness h1 of the first protrusion 220. Although the sponge material can be saved and the sponge 200 will be also easy to bend, in the latter configuration the heat insulation effect will be reduced, affecting the use experience.

[0097] In some embodiments, D3 may be preferably comprised in a range from 0.07 to 0.87, that is, 0.07 ≤ D3 ≤ 0.87. Further, even more preferably, D3 may be comprised in a range from 0.3 to 0.6, that is, 0.3 ≤ D3 ≤ 0.6. Still further preferably, D3 may be 0.45.

[0098] The density of the sponge 200 may be preferably comprised in a range from 13 kg/m³ to 48 kg/m³. For example, the density is 13 kg/m³, 20 kg/m³, 48 kg/m³, etc. Further, even more preferably, the density may be comprised in a range from 14 kg/m³ to 30 kg/m³. For example, the density is 14 kg/m³, 20 kg/m³, 30 kg/m³, etc. Still further preferably, the density may be 16 kg/m³ or 18 kg/ m³.

[0099] In addition, the indentation force deflection of the sponge is associated with the user's comfort during use. In the embodiments of the present application, the indentation force deflection (IFD) of the sponge is tested according to Test B 1 in the standard ASTM D3574-2017. In some embodiments, the 25% IFD may be preferably comprised in a range from 55 N to 100 N, the 40% IFD may be preferably comprised in a range from 80 N to 120 N, and the 65% IFD may be preferably comprised in a range from 190 N to 230 N. Further, even more preferably, for the indentation force deflection of the sponge, the 25% IFD may be 76 N, the 40% IFD may be 100 N, and the 65% IFD may be 210 N.

[0100] In some embodiments, the ratio of 65% IFD to 25% IFD of the sponge 200 is preferably greater than or equal to 2.0. Such a sponge 200 has good load-bearing capacity and is more comfortable for users during use.

[0101] Referring to FIG. 9, the present application takes forming four sponges by cutting as an example, the four sponges being respectively denoted as sponge E, sponge F, sponge G and sponge K. As shown in FIG. 9, during manufacturing of the sponge according to the present application, the sponge blank is first cut in the thickness direction thereof to form the overall outline of the sponge. Then, the sponge blank is cut according to the concave-convex structure of the sponge to form the plurality of first grooves 230 and first protrusions 220, so as to form the concave-convex structure on the upper side of the first sponge E at the top. Then, the sponge blank is transversely cut according to the predetermined thickness of the sponge E and the structure of second protrusions 240 and second grooves 250, so as to form the second grooves 250 and the second protrusions 240 on the lower side of the sponge E. At this time, the sponge E is manufactured. Accordingly, the concave-convex structure (the first grooves 230 and the first protrusions 220) on the upper side of the second sponge F adjacent (immediately below) to the sponge E is also formed.

[0102] Then, the second grooves 250 and the second protrusions 240 on the lower side of the sponge F may be formed by only transversely cutting the sponge blank again according to the thickness of the sponge F and the structure of second protrusions 240 and second grooves 250. At this time, the sponge F is manufactured. Accordingly, the concave-convex structure (the first grooves 230 and the first protrusions 220) on the upper side of the third sponge G (placed adjacent and immediately below the sponge F) is also formed.

[0103] Subsequently, the second grooves 250 and the second protrusions 240 on the lower side of the sponge G may be formed by only transversely cutting the sponge blank again according to the thickness of the sponge G and the structure of second protrusions 240 and second grooves 250. At this time, the sponge G is manufactured. Accordingly, the concave-convex structure (the first grooves 230 and the first protrusions 220) on the upper side of the fourth sponge K (placed adjacent and immediately below the sponge G) is also formed.

[0104] Finally, the concave-convex structure on the lower side of the sponge K may be generated by only cutting the bottom portion of the sponge blank according to the predetermined concave-convex structure of the sponge K to form a plurality of second grooves 250 and a plurality of second protrusions 240. At this time, the four sponges are manufactured.

[0105] From the foregoing, during manufacturing of the four sponges, sponge waste is only generated when a concave-convex structure is formed on the upper side of the sponge E and when a concave-convex structure is formed on the lower side of the sponge K, and no sponge waste is generated during manufacturing of the other two sponges, thereby reducing the waste of sponge. In addition, during the cutting process of two adjacent sponges, the concave-convex structures on the adjacent surfaces of the two adjacent sponges engage with each other, such that concave-convex structures of two adjacent sides of the two adjacent sponges may be formed by only taking one cutting according to the predetermined concave-convex structure of the sponge, so that this solution also simplifies the cutting process and improves the cutting efficiency.

[0106] In this embodiment, as shown in FIGS. 5 and 6, the base of the sponge 200 is provided with first protrusions 220 at both the first end and the second end of the upper side considered in the length direction Y, and the base 210 is provided with second grooves 250 at both the first end and the second end of the lower side, always considered in the length direction Y. Those skilled in the art would understand that, in other embodiments, first grooves 230 may also be provided at the first end and the second end of the upper side of the base 210 of the sponge 200, and second protrusions 240 may be provided at the first end and the second end of the lower side of the base 210 of the sponge 200.

[0107] Alternatively, as shown in FIG. 10, a first groove 230 may be provided at the first end of the upper side of the base 210 of the sponge 200, a second protrusion 240 may be provided at the first end of the lower side of the base 210 of the sponge 200, a first protrusion 220 may be provided at the second end of the upper side of the base 210 of the sponge 200, and a second groove 250 may be provided at the second end of the lower side of the base 210 of the sponge 200.

[0108] Alternatively, a first protrusion 220 is provided at the first end of the upper side of the base 210 of the sponge 200, a second groove 250 is provided at the first end of the lower side of the base 210 of the sponge 200, a first groove 230 is provided at the second end of the upper side of the base 210 of the sponge 200, and a second protrusion 240 is provided at the second end of the lower side of the base 210 of the sponge 200. This embodiment, not shown, may be considered as a mirror image with respect to an axis of symmetry parallel to Z of the embodiment shown in figure 10.

[0109] In some variations of the above embodiment, the cross-sectional shape of the first protrusion 220 perpendicular to the width direction X of the sponge 200 (therefore parallel to the plane YZ) and the cross-sectional shape of the second groove 250 perpendicular to the width direction X of the sponge 200 (therefore parallel to the plane YZ) may also be a trapezoidal shape, an arc shape, a bowl shape, or other suitable shapes as shown in FIGS. 11a-11e.

[0110] The cross-sectional shape of the first groove 230 in the width direction X of the sponge and the cross-sectional shape of the second protrusion 240 in the width direction X of the sponge may also be a trapezoidal shape, an arc shape, a bowl shape or other suitable shapes as shown in FIGS. 11a-11e. All the aforementioned cross-sectional shapes may be the same, and for example, are all trapezoidal. Alternatively, part of the cross-sectional shape may be a bowl shape, and part of the cross-sectional shape may be a trapezoidal shape, an arc shape, or other shapes.

[0111] FIG. 11a shows a schematic cross-sectional view of a sponge according to another embodiment of the present application. As shown in FIG. 11a, the cross-sectional shape of the first protrusion 220 in the middle of the sponge 200 is the same as that of the second groove 250, both being an approximately trapezoidal shape, and the cross-sectional area of the first protrusion 220 is equal to that of the second groove 250. The cross-sectional shape of the first groove 230 in the middle of the sponge 200 is the same as that of the second protrusion 240, both being an approximately inverted trapezoidal shape, and the cross-sectional area of the first groove 230 is equal to that of the second protrusion 240. Optionally, the cross-sectional shape of the first protrusion 220 in the middle of the sponge 200 is the same as but vertically inverted to that of the second protrusion 240, and the cross-sectional area of the first protrusion 220 is equal to that of the second protrusion 240.

[0112] The cross-sectional shape of the first grooves 230 at the two ends of the sponge 200 is the same as that of the second protrusion 240, both being an irregular shape, and the cross-sectional area of the first groove 230 is equal to that of the second protrusion 240. Also in this case, the "ends" are considered along the length direction Y of the sponge.

[0113] In this embodiment, the cross-sectional shape of the first grooves 230 at the two ends of the sponge 200 is different from that of the first groove 230 in the middle of the sponge 200, and the cross-sectional shape of the second protrusions 240 at the two ends of the sponge 200 is different from that of the second protrusion 240 in the middle of the sponge 200.

[0114] Those skilled in the art would understand that in some variations of the above embodiment, the cross-sectional shape of the first groove 230 at the two ends of the sponge 200 is the same as that of the first groove 230 in the middle of the sponge 200; or the cross-sectional shape of the second protrusions 240 at the two ends of the sponge 200 is the same as that of the second protrusion 240 in the middle of the sponge 200; or the cross-sectional shape of the first grooves 230 at the two ends of the sponge 200 is the same as that of the first groove 230 in the middle of the sponge 200, and the cross-sectional shape of the second protrusions 240 at the two ends of the sponge 200 is the same as that of the second protrusion 240 in the middle of the sponge 200.

[0115] FIG. 11b shows a schematic cross-sectional view of a sponge according to another embodiment of the present application. As shown in FIG. 11b, the cross-sectional shape of the first protrusion 220 in the middle of the sponge 200 is the same as that of the second groove 250, both being an inverted trapezoidal shape, and the cross-sectional area of the first protrusion 220 is equal to that of the second groove 250. The cross-sectional shape of the first groove 230 in the middle of the sponge 200 is the same as that of the second protrusion 240, both being trapezoidal, and the cross-sectional area of the first groove 230 is equal to that of the second protrusion 240. Optionally, the cross-sectional shape of the first protrusion 220 in the middle of the sponge 200 is the same as but vertically inverted to that of the second protrusion 240, and the cross-sectional area of the first protrusion 220 is equal to that of the second protrusion 240.

[0116] The cross-sectional shape of the first protrusion 220 at the two ends of the sponge 200 is the same as that of the second groove 250, both being an irregular shape, and the cross-sectional area of the first protrusion 220 is equal to that of the second groove 250. Also in this case, the "ends" are considered along the length direction Y of the sponge.

[0117] In this embodiment, the cross-sectional shape of the first protrusion 220 at the two ends of the sponge 200 is different from that of the first protrusion 220 in the middle of the sponge 200, and the cross-sectional shape of the second groove 250 at the two ends of the sponge 200 is different from that of the second groove 250 in the middle of the sponge 200.

[0118] In some variations of the above embodiment, the cross-sectional shape of the first protrusion 220 at the two ends of the sponge 200 is the same as that of the first protrusion 220 in the middle of the sponge 200; or the cross-sectional shape of the second groove 250 at two end portions of the sponge 200 is the same as that of the second groove 250 in the middle of the sponge 200; or the cross-sectional shape of the first protrusion 220 at the two ends of the sponge 200 is the same as that of the first protrusion 220 in the middle of the sponge 200, and the cross-sectional shape of the second groove 250 at the two ends of the sponge 200 is the same as that of the second groove 250 in the middle of the sponge 200.

[0119] FIG. 11c shows a schematic cross-sectional view of a sponge according to another embodiment of the present application. As shown in FIG. 11c, the cross-sectional shape of the first protrusion 220 in the middle of the sponge 200 is the same as that of the second groove 250, both being an arc shape (or sinusoid-shaped), and the cross-sectional area of the first protrusion 220 is equal to that of the second groove 250. The cross-sectional shape of the first groove 230 in the middle of the sponge 200 is the same as that of the second protrusion 240, both being an arc shape, and the cross-sectional area of the first groove 230 is equal to that of the second protrusion 240. Optionally, the cross-sectional shape of the first protrusion 220 in the middle of the sponge 200 is the same as but vertically inverted to that of the second protrusion 240, and the cross-sectional area of the first protrusion 220 is equal to that of the second protrusion 240.

[0120] The cross-sectional shape of the first protrusion 220 at the two ends of the sponge 200 is the same as that of the second groove 250, both being an irregular shape, and the cross-sectional area of the first protrusion 220 is equal to that of the second groove 250. The "ends" are considered along the length direction Y of the sponge.

[0121] In this embodiment, the cross-sectional shape of the first protrusion 220 at the two ends of the sponge 200 is different from that of the first protrusion 220 in the middle of the sponge 200, and the cross-sectional shape of the second groove 250 at the two ends of the sponge 200 is different from that of the second groove 250 in the middle of the sponge 200.

[0122] In some variations of the above embodiment, the cross-sectional shape of the first protrusion 220 at the two ends of the sponge 200 is the same as that of the first protrusion 220 in the middle of the sponge 200, or the cross-sectional shape of the second groove 250 at the two ends of the sponge 200 is the same as that of the second groove 250 in the middle of the sponge 200; or the cross-sectional shape of the first protrusion 220 at the two ends of the sponge 200 is the same as that of the first protrusion 220 in the middle of the sponge 200, and the cross-sectional shape of the second groove 250 at the two ends of the sponge 200 is the same as that of the second groove 250 in the middle of the sponge 200.

[0123] FIG. 11d shows a schematic cross-sectional view of a sponge according to another embodiment of the present application. As shown in FIG. 11d, the cross-sectional shape of the first protrusion 220 in the middle of the sponge 200 is the same as that of the second groove 250, both being an approximately semicircular shape, and the cross-sectional area of the first protrusion 220 is equal to that of the second groove 250. The cross-sectional shape of the first groove 230 in the middle of the sponge 200 is the same as that of the second protrusion 240, and the cross-sectional area of the first groove 230 is equal to that of the second protrusion 240.

[0124] The cross-sectional shape of the first protrusion 220 at the two ends of the sponge 200 is the same as that of the second groove 250, both being an irregular shape, and the cross-sectional area of the first protrusion 220 is equal to that of the second groove 250. The "ends" are considered along the length direction Y of the sponge. In this embodiment, the cross-sectional shape of the first protrusion 220 at the two ends of the sponge 200 is different from that of the first protrusion 220 in the middle of the sponge 200, and the cross-sectional shape of the second groove 250 at the two ends of the sponge 200 is different from that of the second groove 250 in the middle of the sponge 200.

[0125] In some variations of the above embodiment, the cross-sectional shape of the first protrusion 220 at the two ends of the sponge 200 is the same as that of the first protrusion 220 in the middle of the sponge 200, or the cross-sectional shape of the second groove 250 at the two ends of the sponge 200 is the same as that of the second groove 250 in the middle of the sponge 200; or the cross-sectional shape of the first protrusion 220 at the two ends of the sponge 200 is the same as that of the first protrusion 220 in the middle of the sponge 200, and the cross-sectional shape of the second groove 250 at the two ends of the sponge 200 is the same as that of the second groove 250 in the middle of the sponge 200.

[0126] FIG. 11e shows a schematic cross-sectional view of a sponge according to another embodiment of the present application. As shown in FIG. 11e, the cross-sectional shape of the first protrusion 220 in the middle of the sponge 200 is the same as that of the second groove 250, both being a bowl shape, and the difference from FIG. 11d lies in that the upper end surface of each first protrusion 220 is a flat surface, which can increase the contact area with the top sheet 110, thereby increasing the fitting firmness. The cross-sectional area of the first protrusion 220 is equal to that of the second groove 250. The cross-sectional shape of the first groove 230 in the middle of the sponge 200 is the same as that of the second protrusion 240, and the cross-sectional area of the first groove 230 is equal to that of the second protrusion 240.

[0127] The cross-sectional shape of the first grooves 230 at the two ends of the sponge 200 is the same as that of the second protrusion 240, both being an irregular shape, and the cross-sectional area of the first groove 230 is equal to that of the second protrusion 240. The "ends" are considered along the length direction Y of the sponge.

[0128] In this embodiment, the cross-sectional shape of the first grooves 230 at the two ends of the sponge 200 is different from that of the first groove 230 in the middle of the sponge 200, and the cross-sectional shape of the second protrusions 240 at the two ends of the sponge 200 is different from that of the second protrusion 240 in the middle of the sponge 200.

[0129] In some variations of the above embodiment, the cross-sectional shape of the first groove 230 at the two ends of the sponge 200 is the same as that of the first groove 230 in the middle of the sponge 200; or the cross-sectional shape of the second protrusions 240 at the two ends of the sponge 200 is the same as that of the second protrusion 240 in the middle of the sponge 200; or the cross-sectional shape of the first grooves 230 at the two ends of the sponge 200 is the same as that of the first groove 230 in the middle of the sponge 200, and the cross-sectional shape of the second protrusions 240 at the two ends of the sponge 200 is the same as that of the second protrusion 240 in the middle of the sponge 200.

[0130] Referring to FIG. 12, the four corners of the sponge 200 may be cut into rounded corners. Optionally, as shown in FIG. 12, the upper rounded corner is arranged at the edges of the first protrusion 220, the first groove 230 and the first protrusion 220 at the end portion of the sponge 200. That is, in this embodiment, the upper rounded corner spans the three concave/convex portions. Correspondingly, the lower rounded corner is arranged at the edges of the second groove 250, the second protrusion 240 and the second groove 250 at the end portion of the sponge 200. That is, in this embodiment, the lower rounded corner spans the three concave/convex portions. Those skilled in the art would understand that, in other embodiments, the rounded corner may span one, two or less concave/convex portions, or may span four, five or more concave/convex portions. The radius R of the rounded corner may be preferably comprised in a range from 3 cm to 20 cm. For example, the radius R may be 3 cm, 18 cm or 20 cm, etc. Further, even more preferably, the radius R may be comprised in a range from 5 cm to 15 cm. For example, the radius R may be 5 cm, 10 cm or 15 cm, etc. Still further preferably,, the radius R may be 8.5 cm.

[0131] FIG. 13 shows a schematic exploded view of an inflatable pad according to an embodiment of the present application. As shown in FIG. 13, the embodiment of the present application provides an inflatable pad 100, including: a first wall (also referred to as a top sheet 110), a second wall (also referred to as a bottom sheet 120)and a sponge 200 placed in therebetween. FIG. 13 shows that the sponge structure shown in FIG. 5 is used. However, it can be understood that the sponge 200 placed in the inflatable pad 100 may be of the sponge structure according to any of the implementations described above. The bottom sheet 120 is arranged opposite the top sheet 110 in the thickness direction Z of the inflatable pad 100.

[0132] The top sheet 110 or first wall, may be shaped and sized substantially the same as the bottom sheet 120, or second wall. Advantageously, the peripheral edge of the top sheet 110 is connected to the peripheral edge of the bottom sheet 120, such that the top sheet 110 and the bottom sheet 120 jointly define the inflatable chamber 140.

[0133] An air valve 180 is provided in the inflatable pad, preferably on the first wall 110. The top sheet 110 is configured for the user to sit or lie down, and the bottom sheet 120 is configured to be in contact with the ground. In this embodiment, the top sheet 110 and the bottom sheet 120 may each include an outer layer facing away from the inflatable chamber 140 (the outer layer may also be referred to as a comfort layer) and an inner layer facing the inflatable chamber 140.

[0134] The sponge 200 is arranged in the inflatable chamber 140. The upper surfaces 221 of the plurality of first protrusions 220 fit with the top sheet 110, and the lower surfaces 241 of the plurality of second protrusions 240 fit with the bottom sheet 120. Specifically, the inner surface of the top sheet 110 fits with the upper surfaces 221 of the plurality of first protrusions 220 by means of bonding or hot pressing, and the inner surface of the bottom sheet 120 fits with the lower surfaces 241 of the plurality of second protrusions 240 by means of bonding or hot pressing. In some variations of the above embodiment, the top sheet 110 and/ or the bottom sheet 120 may also present a different structure, and for example, they may be composite or monolayer structures.

[0135] In some embodiments, the top sheet 110 and the bottom sheet 120 are made of the same material and, for example, both are made of polyvinyl chloride (PVC) or thermoplastic urethane (TPU). When the top sheet 110 and the bottom sheet 120 are made of PVC, the plurality of first protrusions 220 are fixed to the inner surface of the top sheet 110 by means of hot pressing or bonding, and the plurality of second protrusions 240 are fixed to the inner surface of the bottom sheet 120 by means of hot pressing or bonding. When the top sheet 110 and the bottom sheet 120 are made of TPU, the plurality of first protrusions 220 are fixed to the inner surface of the top sheet 110 by means of hot pressing or bonding, and the plurality of second protrusions 240 are fixed to the inner surface of the bottom sheet 120 by means of hot pressing or bonding.

[0136] In other embodiments, the top sheet 110 and the bottom sheet 120 may be made of different materials. For example, the top sheet 110 is made of PVC, and the bottom sheet 120 is made of TPU; or the top sheet 110 is made of TPU, and the bottom sheet 120 is made of PVC.

[0137] The air valve 180 is arranged on the top sheet 110 (first wall), and the inflatable chamber 140 may be inflated through the air valve 180, so as to maintain the inflatable pad 100 in a predetermined shape. The inflatable chamber 140 may also be deflated through the air valve 180, such that the inflatable pad 100 is in a deflated state. The top sheet 110 may preferably have a thickness comprised between 0.12 mm and 0.75 mm, and the bottom sheet 120 may have a thickness between 0.12 mm and 0.75 mm.

[0138] The thermal resistance of the inflatable pad according to the present application is tested based on the test standard of ASTM F3340-22. The specific test method includes: inflating an inflatable pad sample to a predetermined internal pressure; then placing a protective upper hot plate above the inflatable pad sample, and placing a protective lower cold plate below the inflatable pad sample, such that the inflatable pad sample is horizontally clamped between the upper hot plate and the lower cold plate; during the testing, maintaining the upper hot plate and the lower cold plate at a constant temperature, and controlling the ambient temperature of the inflatable pad sample to be equal to the average temperature of the hot plate and the cold plate; and under a steady-state condition, measuring the heat flux density passing through the inflatable pad sample, and calculating the thermal resistance of the inflatable pad sample by dividing the temperature difference by the heat flux density.

[0139] In this embodiment, it was found from the testing of the thermal resistance of a plurality of sponge-containing inflatable pad samples that the thermal resistance of the inflatable pad 100 disclosed in the present application is preferably comprised in ranges from 4 ft²•°F•h/Btu to 12 ft²•°F•h/Btu. Further, even more preferably, the thermal resistance of the inflatable pad 100 ranges from 7 ft²•°F•h/Btu to 11 ft²•°F•h/Btu. Specifically, still further preferably, the thermal resistance of the inflatable pad 100 is 9 ft²•°F•h/Btu.

[0140] FIG. 14 show a schematic exploded view of an inflatable pad according to another embodiment of the present application provided with a side wall 130. As shown in FIG. 14, the inflatable pad 100 further includes a side wall (also referred to as a side sheet 130) provided between the top sheet 110 and the bottom sheet 120. Preferably, the side sheet 130 surrounds the sponge 200.

[0141] The peripheral edge of the top sheet 110 is connected to the peripheral edge of the bottom sheet 120 by means of the side sheet 130, such that the top sheet 110, the bottom sheet 120 and the side sheet 130 jointly define the inflatable chamber 140.

[0142] Specifically, the peripheral edge of the top sheet 110 is welded to a top edge of the side sheet 130, and the peripheral edge of the bottom sheet 120 is welded to a bottom edge of the side sheet 130.

[0143] The sponge 200 is arranged in the inflatable chamber 140. Advantageously, the plurality of first protrusions 220 on the sponge 200 fit with the inner surface of the top sheet 110, and the plurality of second protrusions 240 on the sponge 200 fit with the inner surface of the bottom sheet 120. In some embodiments, the top sheet 110 fits with the first protrusion 220 of the sponge 200 by means of hot pressing or bonding.

[0144] In some embodiments, the side sheet 130 is made of the same material as the top sheet 110 and the bottom sheet 120 mentioned above, that is, the top sheet 110, the bottom sheet 120 and the side sheet 130 are all made of PVC or TPU.

[0145] In other embodiments, the side sheet 130 may be made of a different material from the top sheet 110 and the bottom sheet 120. For example, the top sheet 110 and the bottom sheet 120 are made of TPU, and the side sheet 130 is made of PVC; or the top sheet 110 and the bottom sheet 120 are made of PVC, and the side sheet 130 is made of TPU. In this embodiment, providing the side sheet 130 can improve the supportability of the inflatable pad 100, and may also allow the inflatable pad 100 to have a squarer appearance. In this configuration, the inflatable valve 180 may be provided alternatively on the first wall 110 (top sheet) or on the side wall 130 (side sheet).

[0146] FIG. 15 shows a schematic exploded view of an inflatable pad according to another embodiment of the present application. As shown in FIG. 15, the inflatable pad 600 includes: a first wall 610 (also referred to as a top sheet or covering layer)) and a second wall 620 (also referred to as an intermediate sheet), arranged opposite the first wall, connected each other to jointly define a first chamber 640. Preferably, the first chamber 640 may be an inflatable chamber.

[0147] Preferably, an air valve 680 may be present on the first wall 610 to inflate the first inflatable chamber 640.

[0148] A sponge 200 is arranged in the first chamber 640. A plurality of first protrusions 220 of the sponge 200 fit with the first wall 610, and a plurality of second protrusions 240 of the sponge 200 fit with an upper surface of the second wall 620. The fitting may be achieved by means of bonding or hot pressing.

[0149] The second wall 620 may also define an intermediate sheet placed between the first chamber 640 and a second chamber 670. The latter is provided immediately adjacent and below the first chamber 640, as shown in FIG. 15.

[0150] The second chamber 670 is preferably and inflatable chamber.

[0151] The inflatable pad 600, according to the embodiment shown in FIG.15, further comprises a third wall 650 (also referred to as a bottom sheet), arranged opposite the second wall 620 on the other side with respect to the placement of the first wall 610, and a surrounding wall 630 (also referred to as a surrounding sheet) placed between the second wall 620 and the third wall 650. The second wall or intermediate sheet 620 is arranged opposite the third wall 650 in a thickness direction of the inflatable pad. Specifically, the second wall (intermediate sheet) 620 is located above the third wall 650. The intermediate sheet or second wall 620 may have substantially the same shape and size as the bottom sheet or third wall 650. A peripheral edge of the intermediate sheet 620 is welded to an upper peripheral edge of the surrounding wall 630, and a peripheral edge of the bottom sheet 650 is welded to a lower peripheral edge of the surrounding wall 630, such that the surrounding wall or surrounding sheet 630, the third wall or bottom sheet 650, and the second wall or intermediate sheet 620 jointly define a second inflatable chamber 670. One of the air valves 680 is provided on the surrounding sheet 630 for inflating the second inflatable chamber 670.

[0152] The first wall or covering layer 610 is arranged opposite the intermediate sheet 620 in a thickness direction of the sponge 200. Specifically, the covering layer 610 is located above the intermediate sheet 620, the covering layer 610 may have substantially the same shape and size as the intermediate sheet 620 and the bottom sheet 650, and the covering layer 610 and the intermediate sheet 620 are connected to each other to jointly define the first chamber 640. As already disclosed, one of the air valves 680 is also provided on the covering layer 610. The second chamber 670 and the first inflatable chamber 640 are independent of each other, and the first chamber 640 may be inflated or not inflated according to actual use requirements.

[0153] Specifically, in this embodiment, the second wall or intermediate sheet 620 and a base material portion of the first wall or covering layer 610 may be made of the same material as the top sheet 110, the bottom sheet 120 and the side sheet 130 mentioned above with reference to the above described embodiments of FIGS. 13 and 14. The difference lies in that the first wall or covering layer 610 may further include a layer of patch or a flock layer fixed to the base material surface to improve the suppleness and comfort during use by a user.

[0154] In some other embodiments, the second wall or intermediate sheet 620 and the base material portion of the covering layer 610 may be made of a different material from the top sheet 110, the bottom sheet 120 and the side sheet 130. In this embodiment, the inflatable pad 600 is divided into two independent chambers by the second wall or intermediate sheet 620 and the first wall or covering layer 610, such that the user can make a choose according to the actual situation.

[0155] In other embodiments, not explicitly illustrated but not excluded, the inflatable pad shown in FIGS. 13 to 15 may further use the sponge structure described in any of the aforementioned embodiments.

[0156] In order to further improve the heat insulation performance of the inflatable pad, referring to FIG. 16, a first heat insulation sheet 300 is provided on the bottom 231 of the first groove of sponge 200. As shown in FIG. 16, a first heat insulation sheet 300 is provided on the bottom 231 of each of the plurality of first grooves 230. The first heat insulation sheet 300 may fit with the bottom 231 of the first groove 230, or may not fit with the bottom 231 of the first groove 230 of the sponge 200. Since the first protrusions 220 and the second protrusions 240 of the sponge 200 respectively fit with the top sheet 110 and the bottom sheet 120, the first heat insulation sheet 300 cannot move even if the first heat insulation sheet 300 does not fit with the first grooves 230 of the sponge 200.

[0157] In this embodiment, the number of the first heat insulation sheets 300 is equal to the number of the first grooves 230, that is, a first heat insulation sheet 300 is attached to the bottom 231 of each first groove 230. The plurality of first heat insulation sheets 300 are arranged independently, that is, the plurality of first heat insulation sheets 300 are formed independently. In other words, the two adjacent first heat insulation sheets 300 are not connected to each other. In other variations, the number of the first heat insulation sheets 300 may not be equal to that of the first grooves 230, that is, the number of the first heat insulation sheets 300 may be one, two or more.

[0158] Referring to FIG. 17, the plurality of first heat insulation sheets 300 may also be formed integrally, that is, a plurality of first openings 310 corresponding to the first protrusions 220 are formed throughout the first heat insulation sheet 300, and the first openings 310 allow the first protrusions 220 to pass through. The first protrusion 220 is not covered by the first heat insulation sheet 300. Providing the first heat insulation sheets 300 can reduce the heat transfer between the ground and the sponge 200, which improves the heat insulation effect of the sponge 200 to reduce the heat loss of the human body, thereby improving the user's comfort during use.

[0159] In some variations of the above embodiment, some of the first heat insulation sheets 300 may be formed independently, and some of the first heat insulation sheets 300 may be formed integrally. For example, the plurality of first heat insulation sheets 300 at the first end of the sponge 200 may be formed independently, and the first heat insulation sheets 300 at the second end of the sponge 200 may be formed integrally; or the plurality of first heat insulation sheets 300 at the second end of the sponge 200 may be formed independently, and the first heat insulation sheets 300 at the first end of the sponge 200 may be formed integrally.

[0160] Alternatively, the first heat insulation sheets 300 at the first end and the second end of the sponge 200 are respectively formed independently, and the plurality of first heat insulation sheets 300 in the middle of the sponge 200 are formed integrally; or the first heat insulation sheets 300 at the first end and the second end of the sponge 200 are respectively formed integrally, and the plurality of first heat insulation sheets 300 in the middle of the sponge 200 are formed independently.

[0161] In order to further improve the heat insulation effect, as shown in FIG. 18, on the basis that the first heat insulation sheets 300 may be provided on the bottoms 231 of the first grooves 230, second heat insulation sheets 400 may also be provided on the bottoms 251 of the plurality of second grooves 250. In this embodiment, the number of the second heat insulation sheets 400 is equal to that of the second grooves 250, that is, one second heat insulation sheet 400 is provided on the bottom 251 of each second groove 250. The plurality of second heat insulation sheets 400 are arranged independently, that is, the plurality of second heat insulation sheets 400 are formed independently. In other words, the two adj acent second heat insulation sheets 400 are not connected to each other.

[0162] In other variations, the number of the second heat insulation sheets 400 may not be equal to that of the second grooves 250, that is, the number of the second heat insulation sheets 400 may be one, two or more.

[0163] FIG. 19 shows a schematic perspective view of a sponge according to another embodiment of the present application. As shown in FIG. 19, in addition to the plurality of first heat insulation sheets 300 being formed integrally, the plurality of second heat insulation sheets 400 may also be formed integrally. That is, a plurality of second openings 410 corresponding to the second protrusions 240 are formed throughout the second heat insulation sheet 400, and the second openings 410 allow the second protrusions 240 to pass through. The second protrusion 240 is not covered by the second heat insulation sheet 400.

[0164] In some variations of the above embodiment, some of the second heat insulation sheets 400 may be formed independently, and some of the second heat insulation sheets 400 may be formed integrally. For example, the plurality of second heat insulation sheets 400 at the first end of the sponge 200 may be formed independently, and the second heat insulation sheets 400 at the second end of the sponge 200 may be formed integrally; or the plurality of second heat insulation sheets 400 at the second end of the sponge 200 may be formed independently, and the second heat insulation sheets 400 at the first end of the sponge 200 may be formed integrally.

[0165] Alternatively, the second heat insulation sheets 400 at the first end and the second end of the sponge 200 are respectively formed independently, and the plurality of second heat insulation sheets 400 in the middle of the sponge 200 are formed integrally; or the second heat insulation sheets 400 at the first end and the second end of the sponge 200 are respectively formed integrally, and the plurality of second heat insulation sheets 400 in the middle of the sponge 200 are formed independently.

[0166] It is proposed in the embodiment of the present application that the first heat insulation sheet 300 and the second heat insulation sheet 400 may be made of the same material. The first heat insulation sheet 300 and the second heat insulation sheet 400 both include a polymer base material layer and a metal coating on the surface of the polymer base material layer. The metal coating may be aluminum, copper, gold or other metal having a heat insulation effect. The first heat insulation sheet 300 and/or the second heat insulation sheet 400 may fit with the first groove 230 or the second groove 250 by means of hot pressing or bonding.

[0167] In other embodiments, the first heat insulation sheet 300 and/or the second heat insulation sheet 400 may not fit with the first groove 230 or the second groove 250.

[0168] In this embodiment, the first heat insulation sheet 300 and the second heat insulation sheet 400 shown in FIGS. 16 to 19 are both used in an inflatable pad in combination with the sponge structure shown in FIG. 5.

[0169] In other embodiments, the first heat insulation sheet 300 and the second heat insulation sheet 400 may be used in an inflatable pad in combination with the sponge structure according to any of the aforementioned implementations.

[0170] FIG. 20 shows a schematic cross-sectional view of a sponge assembly according to another embodiment. As shown in FIG. 20, the embodiment of the present application further provides a sponge assembly, comprising an upper sponge 200U (also referred to as first sponge) and a lower sponge 200L (also referred to as second sponge). FIG. 20 shows that the sponge structure in FIG. 5 is used. In particular, two sponge structure shown in FIG. 5 are used, overlapped one another. However, it can be understood that the upper sponge 200U the lower sponge 200L may be of the sponge structure according to any of the implementations described above. Specifically, the second protrusions 240 of the upper sponge 200U engage with the first grooves 230 of the lower sponge 200L, and the second groove 250 of the upper sponge 200U engage with the first protrusions 220 of the lower sponge 200L. In this solution, by means of providing the two sponges 200, the overall thickness of the sponge assembly may be increased to adapt to the inflatable chambers 140 of different thicknesses.

[0171] Specifically, an inner surface of the top sheet 110 (also referred to as a lower surface of the top sheet 110) fits with the plurality of first protrusions 220 of the upper sponge 200U by means of bonding or hot pressing, and an inner surface of the bottom sheet 120 (also referred to as an upper surface of the bottom sheet 120) fits with the plurality of second protrusions 240 of the lower sponge 200L by means of bonding or hot pressing.

[0172] Those skilled in the art would understand that, in other alternative embodiments, the number of sponges 200 in the sponge assembly may be three, four, ..., or more. A first heat insulation sheet 300 or a second heat insulation sheet 400 is provided between two adjacent sponges 200, or a first heat insulation sheet 300 or a second heat insulation sheet 400 is provided between portions of the sponges 200.

[0173] Similarly, in order to adapt to cold environments and improve the heat insulation effect, referring to FIG. 21, a third heat insulation sheet 500 is provided between the sponge assemblies in the figure. The third heat insulation sheet 500 may be made of a complete piece of material. As shown in FIG. 21, the third heat insulation sheet 500 is arranged between an upper sponge 200U and a lower sponge 200L. Specifically, the third heat insulation sheet 500 includes an upper surface 510 and a lower surface 520 in the thickness direction of the sponge 200. In some embodiments, the upper surface 510 fits with the plurality of second protrusions 240 and the plurality of second grooves 250 of the upper sponge 200U, that is, the upper surface 510 fits with top faces and side faces of the second grooves 250 of the upper sponge 200U and bottoms and side faces of the second protrusions 240.

[0174] In some embodiments, the lower surface 520 of the third heat insulation sheet 500 fits with the plurality of first protrusions 220 and the plurality of first grooves 230 of the lower sponge 200L. That is, the lower surface 520 fits with the top faces and the side faces of the first protrusions 220 and the bottoms of the first grooves 230 of the lower sponge 200L. The third heat insulation sheet 500 can block the heat transfer between the two sponges 200 to reduce the heat loss of the human body.

[0175] It can be understood that the third heat insulation sheet 500 may be configured as the heat insulation sheet structure shown in FIG. 17, and a plurality of openings corresponding to the second protrusions 240 of the upper sponge 200U are provided throughout the third heat insulation sheet 500 to allow the second protrusions 240 of the upper sponge 200U to pass through.

[0176] Alternatively, a plurality of openings corresponding to the first protrusions 220 of the lower sponge 200L are provided throughout the third heat insulation sheet 500 to allow the first protrusions 220 of the lower sponge 200L to pass through.

[0177] It can also be understood that the third heat insulation sheet 500 may be configured as the heat insulation sheet structure shown in FIG. 16. A plurality of strip-shaped third heat insulation sheets 500 are arranged at the bottoms 231 of the first grooves 230 and/or the upper surfaces 221 of the first protrusions 220 of the lower sponge 200L. The plurality of third heat insulation sheets 500 are independent of each other, that is, not connected to each other.

[0178] It is proposed in the embodiment of the present application that the third heat insulation sheet 500 may be made of the same material as the first heat insulation sheet 300 and/or the second heat insulation sheet 400. The third heat insulation sheet 500 includes a polymer base material layer and a metal coating on the surface of the polymer base material layer. The metal coating may be aluminum, copper, gold or other metal having a heat insulation effect. The third heat insulation sheet 500 may fit with the bottom 231 of the first groove 230 and/or the upper surface 221 of the first protrusion 220 by means of hot pressing or bonding. In other embodiments, the third heat insulation sheet 500 may not fit with the bottom 231 of the first groove 230 and/or the upper surface 221 of the first protrusion 220.

[0179] In summary, the sponge structure described in any of the aforementioned embodiments can save sponge in the thickness direction. Similarly, in order to save sponge in the width direction, the present application further discloses another sponge structure.

[0180] Referring to FIG. 22, an embodiment of the present application further discloses another sponge structure. As shown in FIG. 22, the sponge 700 includes a base 710, a plurality of first transverse protrusions 720, a plurality of second transverse protrusions 740 and a head portion 760. The base 710 extends in the length direction of the sponge (the Y direction as shown in FIG. 22). One first transverse recess 730 is formed between two adjacent first transverse protrusions 720. One second transverse recess 750 is formed between two adjacent second transverse protrusions 740. In other words, except for the end portions, the first transverse protrusion 720 is provided with first transverse recesses 730 on both sides, or the first transverse recess 730 is provided with first transverse protrusions 720 on both sides. Except for the end portions, the second transverse protrusion 740 is provided with second transverse recesses 750 on both sides, or the second transverse recess 750 is provided with second transverse protrusions 740 on both sides. The plurality of first transverse protrusions 720 (also referred to as first protrusions) and the plurality of first transverse recesses 730 (also referred to as first grooves) are provided on a first side of the base 710 in the width direction of the sponge 700 (the X direction as shown in FIG. 22), and the plurality of first transverse protrusions 720 and the plurality of first transverse recesses 730 are arranged alternately. In this embodiment, the first end of the first side of the sponge 700 (i.e., the end close to the head portion 760) may form a first transverse recess 730, and the second end of the first side of the sponge 700 (i.e., the end away from head portion 760) may form a first transverse protrusion 720.

[0181] The plurality of second transverse protrusions 740 (also referred to as second protrusions) and the plurality of second transverse recesses 750 (also referred to as second grooves) are provided on a second side of the base 710 in the width direction X of the sponge 700, and the plurality of second transverse protrusions 740 and the plurality of second transverse recesses 750 are arranged alternately. In this embodiment, a second transverse recess 750 is provided at the first end of the second side of the sponge 700, and a second transverse protrusion 740 is provided at the second end of the second side of the sponge 700.

[0182] The plurality of first transverse protrusions 720 are aligned with the plurality of second transverse protrusions 740 on a one-to-one basis in the width direction of the sponge 700. The plurality of first transverse recesses 730 are aligned with the plurality of second transverse recesses 750 on a one-to-one basis. That is, when a first transverse protrusion 720 is provided on one side of the base 710, a second transverse protrusion 740 is correspondingly provided on the other side of the base 710; or when a first transverse recess 730 is provided on one side of the base 710, a second transverse recess 750 is correspondingly provided on the other side of the base 710. In other words, the plurality of first transverse protrusions 720 are aligned with the plurality of second transverse protrusions 740 in the width direction of the sponge 700.

[0183] The head portion 760 is connected to the base 710 and is arranged at one end of the base 710, and the head portion 760 is used to support the weight of the user's head when the user is lying on the sponge 700. Specifically, in this embodiment, the head portion 760 has a rectangular cross-sectional shape.

[0184] FIG. 23 shows a top view of the sponge structure in FIG. 22. As shown in FIG. 23, the width A of the sponge 700 (considered along the width direction X) may be preferably comprised between 40 cm and 80 cm. For example, A may be 40 cm, 60 cm, or 80 cm. Further, even more preferably, the width A of the sponge 700 is comprised between 50 cm and 70 cm. For example, A may be 50 cm, 60 cm, or 70 cm. Still further preferably, the width A of the sponge 700 may be 65 cm.

[0185] The width A1 of the base 710 (considered along the width direction X) may be preferably comprised between 5 cm and 60 cm. For example, A1 may be 5 cm, 20 cm, 60 cm, etc. Further, even more preferably, the width A1 of the base 710 may be comprised between 15 cm and 40 cm. For example, A1 may be 15 cm, 20 cm, 40 cm, etc. Still further preferably, the width A1 of the base 710 may be 35 cm.

[0186] The width A2 of the first transverse protrusion 720, the width A3 of the second transverse protrusion 740, the width A4 of the first transverse recess 730 and the width A5 of the second transverse recess 750 (all of them considered along the length direction Y) may be preferably equal and between 1 cm and 15 cm. For example, A2, A3, A4 and A5 may be 1 cm, 8 cm, 15 cm, etc. Further, even more preferably, the width A2 of the first transverse protrusion 720, the width A3 of the second transverse protrusion 740, the width A4 of the first transverse recess 730, and the width A5 of the second transverse recess 750 may be comprised between 3 cm and 10 cm. For example, A2, A3, A4, and A5 may be 3 cm, 7 cm, 10 cm, etc. Still further preferably, the width A2 of the first transverse protrusion 720, the width A3 of the second transverse protrusion 740, the width A4 of the first transverse recess 730, and the width A5 of the second transverse recess 750 may be 5 cm.

[0187] The length B 1 of the first transverse protrusion 720 (considered along the width direction X) is preferably equal to the length B2 of the second transverse protrusion 740 (always considered along the width direction X). Specifically, the length B1 of the first transverse protrusion 720 and the length B2 of the second transverse protrusion 740 may be preferably comprised between 5 cm and 37.5 cm. For example, B1 and B2 may be 5 cm, 20 cm, 37.5 cm, etc. Further, even more preferably, the length B1 of the first transverse protrusion 720 and the length B2 of the second transverse protrusion 740 may be comprised between 10 cm and 20 cm. For example, B1 and B2 may be 10 cm, 15 cm, 20 cm, etc. Still further preferably, the length B1 of the first transverse protrusion 720 and the length B2 of the second transverse protrusion 740 may be 15 cm.

[0188] Further, a ratio of the width A1 of the base 710 to the width A2 of the first transverse protrusion 720 is denoted as D4, that is,

.

[0189] Specifically, D4 may be preferably comprised between 0.5 and 30, that is, 0.5 ≤ D4 ≤ 30. Preferably, D4 may be 7.

[0190] Further, a ratio of the width A1 of the base 710 to the length B1 of the first transverse protrusion 720 is denoted as D5, that is,

.

[0191] Specifically, D5 may be preferably comprised between

and 6, that is,

≤ 6. Preferably, D5 may be 2.3.

[0192] Referring to FIG. 24, the present application takes forming two sponges in FIG. 22 by cutting as an example, the two sponges being respectively denoted as sponge S and sponge T. FIG. 24 shows a cutting schematic diagram of the two sponge structures in this embodiment. As shown in FIG. 24, during manufacturing of the sponge according to the present application, a sponge blank is cut according to the concave-convex structure of the sponge to form a head portion 760 of the sponge S and a plurality of first transverse recesses 730 and a plurality of first transverse protrusions 720, so as to form the concave-convex structure of the side of the sponge S away from sponge T. Then the sponge blank is cut according to the width of the sponge and the concave-convex structure of second transverse protrusions 740 and second transverse recesses 750, so as to form the concave-convex structure of the side of the sponge S close to the sponge T. At this time, the sponge S is manufactured, and the corresponding concave-convex structure of the side of the sponge T close to the sponge S is also formed. Subsequently, the head portion of the sponge T is formed by cutting, and the sponge blank is divided according to the width of the sponge and the concave-convex structure of second transverse protrusions 740 and second transverse recesses 750, so as to obtain the concave-convex structure of the side of the sponge T away from the sponge S. At this time, the sponge T is manufactured.

[0193] From the foregoing, during manufacturing of the sponge S and the sponge T, sponge waste is only generated when a concave-convex structure is formed on the side of the sponge S away from the sponge T and when a concave-convex structure is formed on the side of the sponge T away from the sponge S, and no sponge waste is generated in other places, which can thus reduce the waste of sponge in the width direction. In addition, since the sponge S can be in concave-convex fit with the sponge T, the concave-convex structures on the corresponding sides of the sponge S and the sponge T can be formed by only cutting according to the concave-convex structure of the sponge S. Therefore, this solution also simplifies the cutting process and improves the cutting efficiency.

[0194] This embodiment shows the structure and cutting process of two sponges. If the width of the sponge blank is increased, multiple sponges can be formed by cutting in the width direction of the sponge, which can reduce the waste of sponge and improve the cutting efficiency.

[0195] It can be understood that, in some variations of the above embodiment, the cross-sectional shape of the head portion 760 may also be a triangular shape, a trapezoidal shape, an arc shape or a wave shape, or other suitable shapes.

[0196] FIG. 25 shows a schematic perspective view of a sponge structure according to another embodiment of the present application. As shown in FIG. 25, the difference from the embodiment described in FIG. 22 lies in that the head portion 760 has an elliptical cross-sectional shape to better conform to the contour of the human head.

[0197] Referring to FIG. 26, the present application takes forming two sponges in FIG. 25 by cutting as an example, the two sponges being respectively denoted as sponge U and sponge V. FIG. 26 shows a cutting schematic perspective view of the two sponge structures in this embodiment. As shown in FIG. 26, during manufacturing of the sponge of the present application, a sponge blank is cut according to the concave-convex structure of the sponge to form a head portion 760 of the sponge U and a plurality of first transverse recesses 730 and a plurality of first transverse protrusions 720, so as to form the concave-convex structure of the side of the sponge U away from sponge V. Then the sponge blank is cut according to the width of the sponge and the concave-convex structure of second transverse protrusions 740 and second transverse recesses 750, so as to form the concave-convex structure of the side of the sponge U close to the sponge V. At this time, the sponge U is manufactured, and the corresponding concave-convex structure of the side of the sponge V close to the sponge U is also formed. Subsequently, the head portion of the sponge V is formed by cutting, and the sponge blank is divided according to the width of the sponge and the concave-convex structure of second transverse protrusions 740 and second transverse recesses 750, so as to obtain the concave-convex structure of the side of the sponge V away from the sponge U. At this time, the sponge V is manufactured.

[0198] So far, the present application sets forth multiple structures of a sponge and an inflatable pad containing the sponge. According to these embodiments, it is possible to reduce the waste of materials, simplify the cutting process, and reduce the production costs.

[0199] Various substitutions, combinations or modifications can be made to the exemplary implementations disclosed in the present application without departing from the essence of the present application. All such variations are still within the concept of the present application and fall within the scope of protection of the present application as defined by the appended claims.

Claims

1. An inflatable pad, comprising:

a first wall (110, 610);

a second wall (120, 620) arranged opposite the first wall and defining a first inflatable chamber (140, 640) with the first wall (110, 610); and

at least a first sponge (200, 200U) having a length direction (Y), a width direction (X) and a thickness direction (Z) and arranged in said first inflatable chamber (140, 640), said at least first sponge (200, 200U) comprising:

a base (210) extending in the length direction (Y) of the first sponge (200, 200U) and comprising a first side (211) and a second side (212) in the thickness, direction (Z) of the first sponge (200, 200U);

a plurality of first protrusions (220) arranged at intervals on the first side (211) of the base (210), two adjacent of the plurality of first protrusions (220) defining a first groove (230), and the plurality of first protrusions (220) fitting with the first wall (110, 610); and

a plurality of second protrusions (240) arranged at intervals on the second side (212) of the base (210), two adjacent of the plurality of second protrusions (240) defining a second groove (250),

wherein one of the first grooves (230) is aligned with one of the plurality of second protrusions (240) in the thickness direction (Z) of the first sponge (200, 200U), and one of the second grooves (250) is aligned with one of the plurality of first protrusions (220) in the thickness direction (Z) of the first sponge (200, 200U).

2. The inflatable pad according to claim 1, characterized in that the plurality of second protrusions (240) fits with the second wall (120, 620).

3. The inflatable pad according to claim 1, characterized in that the inflatable pad further comprises a side wall (130) arranged between the first wall (110) and the second wall (120) and surrounding the first sponge (200, 200U); wherein the first wall (110), the second wall (120) and the side wall (130) jointly define said first inflatable chamber (140).

4. The inflatable pad according to claim 1, characterized in that the cross-section of the one of the first grooves (230) perpendicular to the width direction (X) of the first sponge (200, 200U) is the same as the cross-section, perpendicular to the width direction (X) of the first sponge (200, 200U), of the second protrusion (240) aligned with the one of the first grooves (230) in the thickness direction (Z) of the first sponge (200, 200U); and the cross-section of the one of the second groove (250) perpendicular to the width direction (X) of the first sponge (200, 200U) is the same as the cross-section, perpendicular to the width direction (X) of the first sponge (200, 200U), of the first protrusion (220) aligned with the one of the second grooves (250) in the thickness direction (Z) of the first sponge (200, 200U).

5. The inflatable pad according to claim 1, characterized in that the thickness of the first protrusion (220) and/or of the second protrusions (240) ranges from 1 cm to 7 cm.

6. The inflatable pad according to claim 1, characterized in that the width of the first groove (230) and/or of the second grooves (250) ranges from 0.5 cm to 8 cm.

7. The inflatable pad according to any of the preceding claims, characterized in that a ratio of the width of the first groove (230) or of the second groove (250) to the depth respectively of the first groove (250) or of the second groove (250) ranges from 0.2 to 5.

8. The inflatable pad according to any of the preceding claims, characterized in that a ratio of the thickness of the base (210) of the first sponge (200, 200U) to the total thickness of the first sponge (200, 200U) ranges from 0.07 to 0.87.

9. The inflatable pad according to any of the preceding claims, characterized in that all of the plurality of first protrusions (220) have the same cross-section perpendicular to the width direction (X) of the first sponge (200, 200U), and all of the plurality of second protrusions (240) have the same cross-section perpendicular to the width direction (X) of the first sponge (200, 200U).

10. The inflatable pad according to the previous claim, characterized in that the cross-section of the first protrusions (220) perpendicular to the width direction (X) of the first sponge (200, 200U) is the same as the cross-section of the second protrusions (240) perpendicular to the width direction (X) of the first sponge (200, 200U).

11. The inflatable pad according to claim 1, characterized in that at least one of the plurality of first grooves (230) and/or at least one of the plurality of second grooves (250) is provided with a heat insulation sheet (300, 400) at a respective bottom.

12. The inflatable pad according to claim 11, characterized in that a plurality of first and/or second heat insulation sheets (300, 400) are provided at the bottom of each first and/or second groove (230, 250); said plurality of first and/or second heat insulation sheets (300, 400) being formed integrally or arranged independently.

13. The inflatable pad according to claim 12, wherein, when the first and/or second heat insulation sheets (300, 400) are formed integrally,

- the first heat insulation sheet (300) presents first openings (310) formed throughout the first heat insulation sheet (300), each of said first openings (310) corresponding to each first protrusions (220), and

- the second heat insulation sheets (400) presents second openings (410) formed throughout the second insulation sheet (400), each of said second openings (410) corresponding to each second protrusions (240).

14. The inflatable pad according to claim 1, characterized in that it further comprises a second sponge (200L) having a length direction (Y), a width direction (X) and a thickness direction (Z) and arranged in the first inflatable chamber (140, 640), the second sponge (200L) comprising:

a base (210) extending in the length direction (Y) of the second sponge (200L) and comprising a first side (211) and a second side (212) in the thickness direction (Z) of the second sponge (200L);

a plurality of first protrusions (220) arranged at intervals on the first side (211) of the base (210), two adjacent of the plurality of first protrusions (220) defining a first groove (230); and

a plurality of second protrusions (240) arranged at intervals on the second side (212) of the base (210), two adjacent of the plurality of second protrusions (240) defining a second groove (250), and the plurality of second protrusions (240) fitting with the second wall (120, 620);

wherein one of the first grooves (230) is aligned with one of the plurality of second protrusions (240) in the thickness direction (Z) of the second sponge (200L), and one of the second grooves (250) is aligned with one of the plurality of first protrusions (220) in the thickness direction (Z) of the second sponge (200L); and

the second protrusions (240) of the first sponge (200U) engage with the first grooves (230) of the second sponge (200L), and the second groove (250) of the first sponge (200U) engage with the first protrusions (220) of the second sponge (220L).

15. The inflatable pad according to the preceding claim, characterized by further comprising a heat insulation sheet (500) provided between the first sponge (200U) and the second sponge (200L).

16. The inflatable pad according to claims 14 or 15, wherein the plurality of second protrusions (240) of the second sponge (200L) fits with the second wall (120, 620).

17. The inflatable pad according to any of the preceding claims, characterized in that it further comprises:

- a third wall (650) arranged opposite the second wall (620), so that the second wall (620) is arranged between the first wall (610) and the third wall (650),

- a surrounding wall (630) arranged between the third wall (650) and the second wall (620);

wherein the third wall (650), the second wall (620) and the surrounding wall (630) jointly define a second inflatable chamber (670); the first inflatable chamber (640) and the second inflatable chamber (670) being independent of each other.

Drawing