Embodiments of the present disclosure relate to the technical field of refrigeration appliances, and in particular, to a refrigeration appliance.

Currently, a refrigeration appliance on the market, especially a refrigeration appliance having an ice-making function, introduces water from an outside into an interior of a box body to meet a water demand. A section of a water pipe located at a thermal insulating layer of the refrigeration appliance needs to be additionally sleeved with protective pipes for protection, and a sealing requirement is imposed on a junction of the protective pipes, so as to prevent a thermal insulating material from entering a pipeline through the junction and causing a blockage during foaming.

Currently, one commonly used sealing manner is wrapping a plurality of layers of sponge tape at the junction, which does not meet a current concept of environmental protection and easily results in a cumbersome and time-consuming mounting process. Especially, for a refrigeration appliance provided with a complex ice-water system, since a large quantity of protective pipes are used, if the plurality of layers of sponge tape are wrapped around each junction during the assembly of the box body to prevent leakage, the entire assembly process is quite cumbersome and time-consuming.

Embodiments of the present disclosure are intended to provide an improved refrigeration appliance.

Therefore, the embodiments of the present disclosure provide a refrigeration appliance, including: an inner housing for defining a storage space, an outer housing wrapping the inner housing, a thermal insulating layer located between the inner housing and the outer housing, a first pipe and a second pipe that are at least partially located in the thermal insulating layer, and a water pipe running through the first pipe and the second pipe. The first pipe has a first end and a second end that are opposite to each other. The second pipe has a connecting end. The first end is hermetically connected to the connecting end. An outer peripheral surface of the first pipe is provided with a sealing rib that protrudes outward. The sealing rib is closer to the first end than the second end, and is configured to be in tight fit with an end portion of the connecting end after the first end is inserted into the connecting end, to form a sealing structure.

In this implementation, the first pipe is provided with a circle of sealing ribs. After the first end of the first pipe is inserted into the connecting end of the second pipe, a sealing structure for sealing the junction of the first pipe and the second pipe is formed through tightly fitting between the sealing ribs and the end portion of the connecting end. Therefore, sealing can be implemented without an additional sealing member such as the sponge tape, which is environmentally friendly. Further, during insertion of the first pipe into the second pipe, the first pipe is not limited by excessive resistance, so that the first pipe can be quickly inserted into position in a smoother and low-wear state, and assembly of the first pipe and the second pipe is more labor-saving and efficient. Further, after the first pipe is inserted into position, the sealing ribs and the end portion of the connecting end are tightly fitted to complete sealing, thereby improving sealing reliability.

Optionally, a side of the sealing rib facing the first end is an arc surface or is an inclined surface at a non-zero angle to a radial direction of the first pipe. The design of the arc surface or the inclined surface enables that an opening of the second pipe tends to radially expand when the first pipe is inserted into the end portion at which the sealing rib contacts the connecting end. As the first pipe is further inserted, the arc surface or the inclined surface is gradually engaged with the connecting end, and the first pipe is better engaged depending on a retractive force generated due to expansion of the connecting end, to implement and strengthen the sealing effect.

Optionally, as the first end is inserted into the connecting end, the connecting end undergoes a radial outward deformation under abutment of the sealing rib. Therefore, after the first pipe is connected to the second pipe, in a normal use process of the refrigeration appliance, the connecting end of the second pipe is always tightly clamped around the sealing rib, thereby ensuring sealing reliability.

Optionally, a chamfered or inclined connection is formed between an end wall of the connecting end and an inner surface of the second pipe. Therefore, the first end of the first pipe can be more smoothly inserted into the second pipe, further reducing assembly effort.

Optionally, an outer surface of a section of the first pipe extending into the second pipe has a non-zero gap or is in virtual contact with the inner surface of the second pipe. Therefore, a process of inserting the first pipe into the second pipe is smoother, and the sealing structure formed at the junction can reliably prevent the external liquid (for example, a thermal insulating material) from entering the inner space from the junction of the first pipe and the second pipe.

Optionally, the second end or an end portion of the second pipe away from the connecting end is connected to the outer housing or the inner housing. Therefore, the first pipe or the second pipe may be used as a connecting member to connect to another component in the refrigeration appliance.

Optionally, the refrigeration appliance further includes: a fixing portion, protruding outward from the outer peripheral surface of the first pipe and located between the first end and the sealing rib; and a limiting hole, provided in the connecting end, where the end wall of the connecting end is provided with an opening in communication with the limiting hole, and the fixing portion enters from the opening and is limited in the limiting hole to limit relative movement between the first pipe and the second pipe. Therefore, through matching of the fixing portion and the limiting hole, the first pipe and the second pipe are locked at a position in which the sealing rib is tightly matched with the connecting end, and a sealing effect is prevented from being damaged by rotation or movement of the first pipe and/or the second pipe during assembly.

Optionally, the limiting hole includes a first hole and a second hole that are in communication with each other. The first hole is located between the second hole and the opening and is in communication with the opening. A stop step retracting toward a center of the limiting hole is formed at a junction of the first hole and the second hole. During assembly, as the first pipe is inserted into the second pipe, the fixing portion runs through the first hole through the opening and then enters the second hole. In this case, the first pipe is inserted into position. Limited by the stop step, the fixing portion cannot be easily returned to the first hole, to limit the first pipe from disengaging from the second pipe, thereby keeping the sealing rib and the end portion of the connecting end in a tight fit state to ensure a good sealing effect.

Optionally, walls of the connecting end that form the first holes oppositely extend in a direction from the opening toward the second hole. Therefore, the first hole is in a shape of a horn that is wide open toward the opening, to help guide the fixing portion to enter the second hole.

Optionally, an inner diameter at the opening is greater than or equal to a maximum width of the fixing portions. Therefore, the fixing portion can smoothly enter the first hole through the openings.

Optionally, an inner diameter at the stop step is less than the maximum width of the fixing portions. Therefore, after entering the second hole, the fixing portion is limited to return to the first hole to avoid that the first pipe is unexpectedly disengaged from the second pipe, ensuring connection reliability and sealing reliability of the first pipe and the second pipe.

Optionally, an inner diameter of the second hole is greater than or equal to the maximum width of the fixing portions, to reliably accommodate the fixing portion.

Optionally, a value of an included angle between a surface of the stop step facing the second hole and an axial direction of the second pipe is in a range of [90°, 45°], to ensure a good locking effect. Further, a larger included angle indicates a better locking effect on the fixing portion.

Optionally, the included angle between the surface of the stop step facing the second hole and the axial direction of the second pipe is greater than an included angle between each of the walls of the connecting end that forms the first hole and the axial direction of the second pipe. Therefore, a disassembly force of the first pipe is greater than an assembly force when the first pipe is inserted into the second pipe after assembly, thereby further ensuring stability of connection between the first pipe and the second pipe.

Optionally, an outer surface of the fixing portion at least on a side facing the sealing rib is an arc surface or an inclined surface. Therefore, it is avoided that the fixing portion and the limiting hole are completely locked after the first pipe is inserted into the second pipe, so that the first pipe is easily disassembled for maintenance.

Optionally, the fixing portion is in a shape of a cylindrical cam, and a tip of a cam faces the first end. Therefore, the disassembly force of the first pipe is greater than the assembly force when the first pipe is inserted into the second pipe after assembly, which helps reduce assembly difficulty and can take both locking reliability and a possible disassembly requirement of the first pipe into consideration.

Optionally, a plurality of fixing portions are arranged at intervals in a circumferential direction of the first pipe, a plurality of limiting holes are provided, and the plurality of limiting holes are in one-to-one correspondence with the plurality of fixing portions. Therefore, limiting and locking functions can be better achieved.

Optionally, shapes and/or sizes of at least one fixing portion among the plurality of fixing portions and a corresponding limiting hole are different from shapes and/or sizes of remaining fixing portions and corresponding limiting holes. Therefore, a fool-proofing function can be achieved.

Optionally, two of the plurality of fixing portions are arranged, and the two fixing portions are symmetrically arranged in a radial direction of the first pipe. Therefore, the limiting and locking function is provided on two sides in the radial direction.

Optionally, a distance between the fixing portion and the sealing rib is less than or equal to a distance between the limiting hole and the end wall of the connecting end. Therefore, it is ensured that the first pipe is locked in a position in which the sealing rib tightly engages with the end wall after assembly, thereby improving reliability of the sealing structure.

• FIG. 1 is a schematic diagram of a refrigeration appliance according to an embodiment of the present disclosure.
• FIG. 2 is a partial enlarged view of a region A in FIG. 1.
• FIG. 3 is a first schematic diagram of assembly of a first pipe and a second pipe according to an embodiment of the present disclosure.
• FIG. 4 is a cross-sectional view along a direction B-B in FIG. 3.
• FIG. 5 is a partial enlarged view of a region C in FIG. 4.
• FIG. 6 is a schematic diagram of the structure shown in FIG. 3 from another perspective.
• FIG. 7 is a partial enlarged view of a region D in FIG. 6.
• FIG. 8 is a second schematic diagram of assembly of a first pipe and a second pipe according to an embodiment of the present disclosure.
• FIG. 9 is a cross-sectional view along a direction E-E in FIG. 8.
• FIG. 10 is a partial enlarged view of a region F in FIG. 9.
• FIG. 11 is a schematic diagram of the structure shown in FIG. 8 from another perspective.
• FIG. 12 is a partial enlarged view of a region G in FIG. 11.
• FIG. 13 is an exploded view of the structure shown in FIG. 8.
• FIG. 14 is a cross-sectional view along a direction H-H in FIG. 13.
• FIG. 15 is a schematic diagram of a second pipe in FIG. 12.

In the drawings:
1-Refrigeration appliance; 10-Inner housing; 11-Outer housing; 12-Thermal insulating layer; 13-Water pipe; 14-Protective pipe; 2-First pipe; 2a-First end; 2b-Second end; 21-Sealing rib; 22-Outer surface of a first pipe; 23-Fixing portion; 3-Second pipe; 3a-Connecting end; 3b-End portion of a second pipe away from a connecting end; 31-End wall of a connecting end; 32-Inner surface of a second pipe; 33-Limiting hole; 331-Opening; 332-First hole; 333-Second hole; 334-Stop step; 34-Open port; d1-Inner diameter of an opening; d2-Inner diameter of a stop step; d3-Inner diameter of a second hole; L1-Maximum width of a fixing portion; β-Included angle between a surface of a stop step facing a second hole and an axial direction of a second pipe; α-Included angle between a wall of a connecting end that forms a first hole and an axial direction of a second pipe; r-Axial direction.

As stated in the background, a sealing measure of a protective pipe and a protective pipe junction in an existing refrigeration appliance has disadvantages of being non-environmentally friendly and complex assembly operations.

Currently, another commonly used sealing manner is to cause, in two adjacent sections of protective pipes (which are denoted as a protective pipe A and a protective pipe B), a diameter of the protective pipe A to be slightly greater than a diameter of the protective pipe B, so that the protective pipe A is inserted into the protective pipe B in an interference fit manner. A sealing function is achieved through tightly fitting between the protective pipe A and the protective pipe B in an overlapping region of an inner peripheral surface and an outer peripheral surface. Although the design can save use of sponge tape, operators need to consume very large force to implement the design during assembly. In addition, the protective pipe A may not be assembled in position due to excessively large insertion resistance during mounting, affecting a sealing effect.

To resolve the foregoing technical problem, embodiments of the present disclosure provide a refrigeration appliance, including: an inner housing for defining a storage space, an outer housing wrapping the inner housing, a thermal insulating layer located between the inner housing and the outer housing, a first pipe and a second pipe that are at least partially located in the thermal insulating layer, and a water pipe running through the first pipe and the second pipe. The first pipe has a first end and a second end that are opposite to each other. The second pipe has a connecting end. The first end is hermetically connected to the connecting end. An outer peripheral surface of the first pipe is provided with a sealing rib that protrudes outward. The sealing rib is closer to the first end than the second end, and is configured to be in tight fit with an end portion of the connecting end after the first end is inserted into the connecting end, to form a sealing structure.

Based on the above, in this implementation, the first pipe is provided with a circle of sealing ribs. After the first end of the first pipe is inserted into the connecting end of the second pipe, a sealing structure for sealing the junction of the first pipe and the second pipe is formed through tightly fitting between the sealing ribs and the end portion of the connecting end. Therefore, sealing can be implemented without an additional sealing member such as the sponge tape, which is environmentally friendly. Further, during insertion of the first pipe into the second pipe, the first pipe is not limited by excessive resistance, so that the first pipe can be quickly inserted into position in a smoother and low-wear state, and assembly of the first pipe and the second pipe is more labor-saving and efficient. Further, after the first pipe is inserted into position, the sealing ribs and the end portion of the connecting end are tightly fitted to complete sealing, thereby improving sealing reliability.

To make the foregoing objectives, characteristics, and advantages of the present disclosure clearer and easier to understand, specific embodiments of the present disclosure are described in detail below with reference to drawings.

FIG. 1 is a schematic diagram of a refrigeration appliance 1 according to an embodiment of the present disclosure.

The refrigeration appliance 1 may be, for example, a refrigerator, a freezer, and a wine cabinet.

Specifically, referring to FIG. 1, the refrigeration appliance 1 may include a box body and doors. The box body includes an inner housing 10 for defining a storage space and an outer housing 11 wrapping the inner housing 10. The object storage space may be further divided into at least one chamber by the inner housing 10. A part of the outer housing 11 is omitted in FIG. 1, to show an internal structure of the box body more clearly.

The door is movably connected to a front portion of the box body to open or close at least one part of the chamber. Using the refrigerator as an example, the chamber may be, for example, a freezing compartment, a refrigerating compartment, a temperature-changing chamber. FIG. 1 exemplarily shows two chambers arranged above and below, with an upper one being the refrigerating compartment and the lower one the freezing compartment.

Further, a thermal insulating layer 12 is arranged between the inner housing 10 and the outer housing 11. The door may further include a thermal insulation space filled with a thermal insulation material. When the door closes the chamber, the thermal insulating layer 12 formed by the thermal insulation space provides thermal insulation to ensure that the chamber has a desirable refrigerating/freezing effect.

Referring to FIG. 1 to FIG. 4, the refrigeration appliance 1 further includes a first pipe 2 and a second pipe 3 that are at least partially located in the thermal insulating layer 12 and a water pipe 13 running through the first pipe 2 and the second pipe 3. Specifically, the outer housing 11 is provided with at least one open port 34, at least one protective pipe 14 is paved on the thermal insulating layer 12, two ends of each protective pipe 14 are respectively connected to a corresponding open port 34 and a corresponding inner housing 10, and at least one water pipe 13 extends from the at least one open port 34 into the corresponding protective pipe 14 and extends to the corresponding inner housing 10. Therefore, the protective pipe 14 may have a function of isolation and protection, to prevent the water pipe 13 from being directly exposed to the thermal insulating layer 12. For example, the outer housing 11 located at a top portion may be provided with the open port 34, and the protective pipe 14 is arranged in the thermal insulating layer 12 to connect the open port 34 to an upper refrigerating compartment, to guide external water to the refrigerating compartment. For another example, the outer housing 11 on a rear side may be provided with the open port 34. The protective pipe 14 is arranged in the thermal insulating layer 12 to connect to the open port 34 and a freezing room at a bottom, to guide the external water to the freezing compartment, for example, supply water to an ice maker in the freezing compartment.

Further, the protective pipe 14 may include a plurality of sections of pipes that are successively connected along an extending direction, and any two sections of pipes that are connected may be a first pipe 2 and a second pipe 3, respectively. Using FIG. 2 and FIG. 3 as an example, the second pipe 3 may be connected to the open port 34, the first pipe 2 may be connected to the second pipe 3, and one end of the first pipe 2 away from the second pipe 3 is indirectly connected to the inner housing 10.

Further, referring to FIG. 2 to FIG. 5, the first pipe 2 has a first end 2a and a second end 2b that are opposite to each other, the second pipe 3 has a connecting end 3a, and the first end 2a is hermetically connected to the connecting end 3a. For example, an end portion 3b of the second pipe 3 away from the connecting end 3a is connected to the open port 34, the connecting end 3a is hermetically connected to the first end 2a, and the second end 2b is directly or indirectly connected to the inner housing 10.

Further, referring to FIG. 3 to FIG. 5 and FIG. 8 to FIG. 10, an outer peripheral surface of the first pipe 2 is provided with a sealing rib 21 that protrudes outward, and the sealing rib 21 is closer to the first end 2a than the second end 2b. The sealing rib 21 is configured to be in tight fit with an end portion of the connecting end 3a after the first end 2a is inserted into the connecting end 3a, to form a sealing structure.

During assembly, the first end 2a of the first pipe 2 is inserted into the second pipe 3 from the connecting end 3a until the end wall 31 of the connecting end 3a abuts against the sealing rib 21. In this case, the end portion of the connecting end 3a is tightly fitted to the sealing rib 21 to form a sealing structure around an outer periphery of a pipe at an initial contact region between a position that the first pipe 2 and the second pipe 3 are inserted and an outside (for example, the thermal insulating layer 2).

Further, the sealing structure is formed at the end portion of the connecting end 3a, and is formed at a final stage (namely, the end portion of the connecting end 3a approaches the sealing rib 21) of inserting the first pipe 2 into the second pipe 3. The sealing structure formed around the end wall 31 of the connecting end 3a in a circle can block a gap between the first pipe 2 and the second pipe 3.

Therefore, the first pipe 2 is provided with a circle of sealing ribs 21. After the first end 2a of the first pipe 2 is inserted into the connecting end 3a of the second pipe 3, a sealing structure for sealing the junction of the first pipe 2 and the second pipe 3 is formed through tightly fitting between the sealing ribs 21 and the end portion of the connecting end 3a. Therefore, sealing can be implemented without an additional sealing member such as the sponge tape, which is environmentally friendly. Further, during insertion of the first pipe 2 into the second pipe 3, the first pipe 2 is not limited by excessive resistance, so that the first pipe can be quickly inserted into position in a smoother and low-wear state, and assembly of the first pipe 2 and the second pipe 3 is more labor-saving and efficient. Further, after the first pipe 2 is inserted into position, the sealing ribs 21 and the end portion of the connecting end 3a are tightly fitted to complete sealing, thereby improving sealing reliability.

In a specific implementation, referring to FIG. 2 to FIG. 12, a side of the sealing rib 21 facing the first end 2a is an arc surface. For example, the sealing rib 21 may protrude from an outer surface of the first pipe 2 in a radial direction of the first pipe 2 to have an arch shape.

Alternatively, a side of the sealing rib 21 facing the first end 2a may be an inclined surface at a non-zero angle to a radial direction of the first pipe 2. For example, a side of the sealing rib 21 facing the first end 2a may obliquely extend toward an axis of the first pipe 2 and toward the first end 2a, to form an inclined surface.

Therefore, the design of the arc surface or the inclined surface enables that an opening of the second pipe 3 tends to radially expand when the first pipe 2 is inserted into the end portion at which the sealing rib 21 contacts the connecting end 3a. As the first pipe 2 is further inserted, the arc surface or the inclined surface is gradually engaged with the connecting end 3a, and the first pipe 2 is better engaged depending on a retractive force generated due to expansion of the connecting end 3a, to implement and strengthen the sealing effect.

Further, as the first end 2a is inserted into the connecting end 3a, the connecting end 3a undergoes a radial outward deformation under abutment of the sealing rib 21. Therefore, after the first pipe 2 is connected to the second pipe 3, in a normal use process of the refrigeration appliance 1, the connecting end 3a of the second pipe 3 is always tightly clamped around the sealing rib 21, thereby ensuring sealing reliability.

In a specific implementation, referring to FIG. 5, a chamfer or a rounded corner between an end wall 31 of the connecting end 3a and an inner surface 32 of the second pipe 3 may exist. Alternatively, referring to FIG. 10 and FIG. 13, an inclined connection may be performed on the end wall 31 and the inner surface 32. As the first pipe 2 is inserted, the arc surface or the inclined surface of the sealing rib 21 is gradually engaged with the connecting end 3a of the second pipe 3, and the chamfer, the rounded corner, or the inclined surface arranged at the connecting end 3a is guided to at least partially cross the arc surface or the inclined surface of the sealing rib 21, so that the connecting end 3a of the second pipe 3 has a more obvious tendency to radially expand, and the first pipe 2 is engaged based on a retractive force generated due to expansion of the connecting end 3a of the second pipe 3, to implement sealing.

Further, the inclined surface or the chamfer is arranged on the inner surface 32 at the connecting end 3a, to further provide a guiding function. Therefore, the first end 2a of the first pipe 2 can be more smoothly inserted into the second pipe 3, further reducing assembly effort.

In a specific implementation, referring to FIG. 5, FIG. 10, and FIG. 14, an outer surface 22 of a section of the first pipe 2 extending into the second pipe 3 may have a non-zero gap or is in virtual contact with the inner surface 32 of the second pipe 3. In other words, sealing between the first pipe 2 and the second pipe 3 is not implemented through surface-to-surface contact between the inner surface 32 and the outer surface 22, but is implemented through matching between the end portion located at the connecting end 3a and the sealing rib 21. In this way, external liquid can also be prevented from entering between the inner surface 32 and the outer surface 22. Therefore, a process of inserting the first pipe 2 into the second pipe 3 is smoother, and the sealing structure formed at the junction can reliably prevent the external liquid (for example, a thermal insulating material) from entering the inner space from the junction of the first pipe 2 and the second pipe 3.

In a variation, a gap between the outer surface 22 of the section that extends into the second pipe 3 of the first pipe 2 and the inner surface 32 of the second pipe 3 may also be zero. In other words, the outer surface of the first pipe 2 close to the first end 2a may be inserted into the connecting end 3a of the second pipe 3 almost against the inner surface 32 of the second pipe 3.

In a variation, an outer diameter of the first end 2a of the first pipe 2 may be slightly greater than an inner diameter of the connecting end 3a of the second pipe 3, so that the first end 2a of the first pipe 2 can be inserted into the connecting end 3a of the second pipe 3 in tight fit, which helps to further improve the sealing effect. In this example, the gap between the outer surface 22 of the section where the first pipe 2 extends into the second pipe 3 and the inner surface 32 of the second pipe 3 may be equivalent to being less than zero.

In a specific implementation, the second end 2b or the end portion 3b of the second pipe 3 away from the connecting end 3a may be connected to the outer housing 11 or the inner housing 10. Using the embodiments shown in FIG. 1 to FIG. 7 as an example, the second end 2b of the first pipe 2 is indirectly connected to the inner housing 10, and the end portion 3b of the second pipe 3 is connected to the open port 34 formed in the outer housing 11. Therefore, the first pipe 2 or the second pipe 3 may be used as a connecting member to connect to another component in the refrigeration appliance 1. The connecting member is a protective pipe 14 having a connecting function.

In another specific embodiment, referring to FIG. 8 to FIG. 15, the first pipe 2 and the second pipe 3 may both be commonly used protective pipes 14. In other words, the second end 2b or the end portion 3b of the second pipe 3 away from the connecting end 3a may be connected to another protective pipe 14.

In a specific implementation, referring to FIG. 6, FIG. 7, FIG. 11, and FIG. 12, the refrigeration appliance 1 may further include a fixing portion 23 protruding outward from the outer peripheral surface of the first pipe 2 and located between the first end 2a and the sealing rib 21. For example, the fixing portion 23 may be arranged close to the sealing rib 21, and a non-zero space is defined between the fixing portion 23 and the sealing rib 21.

Further, still referring to FIG. 6, FIG. 7, FIG. 11, and FIG. 12, the refrigeration appliance 1 may further include a limiting hole 33 provided in the connecting end 3a. The end wall 31 of the connecting end 3a is provided with an opening 331 in communication with the limiting hole 33. During assembly, the first end 2a of the first pipe 2 is inserted into the connecting end 3a. As the first pipe 2 is inserted, the fixing portion 23 may enter from the opening 331 and be limited to be located in the limiting hole 33, to limit a relative movement of the first pipe 2 and the second pipe 3, and the sealing rib 21 is tightly fitted with the end portion of the connecting end 3a to form a sealing structure.

Therefore, through matching of the fixing portion 23 and the limiting hole 33, the first pipe 2 and the second pipe 3 are locked at a position in which the sealing rib 21 is tightly matched with the connecting end 3a, and a sealing effect is prevented from being damaged by rotation or movement of the first pipe 2 and/or the second pipe 3 during assembly.

Further, referring to FIG. 7 and FIG. 12 to FIG. 15, the limiting hole 33 may include a first hole 332 and a second hole 333 that are in communication with each other. The first hole 332 is located between the second hole 333 and the opening 331 and is in communication with the opening 331. A stop step 334 retracting toward a center of the limiting hole 33 is formed at a junction of the first hole 332 and the second hole 333. During assembly, as the first pipe 2 is inserted into the second pipe 3, the fixing portion 23 runs through the first hole 332 through the opening 331 and then enters the second hole 333. In this case, the first pipe 2 is inserted into position. Limited by the stop step 334, the fixing portion 23 cannot be easily returned to the first hole 332, to limit the first pipe 2 from disengaging from the second pipe 3, thereby keeping the sealing rib 21 and the end portion of the connecting end 3a in a tight fit state to ensure a good sealing effect.

In some embodiments, walls of the connecting end 3a that form the first holes 332 may oppositely extend in a direction from the opening 331 toward the second hole 333. For example, a wall configured to form the first hole 332 close to the connecting end 3a of the second pipe 3 may be a planar wall, and obliquely extends from the opening 331 to the second hole 333. Therefore, the first hole 332 may be in a shape of a horn that is wide open toward the opening 331, to help guide the fixing portion 23 to enter the second hole 333.

Further, the limiting hole 33 gradually narrows and extends from the opening 331 to a direction away from the connecting end 3a to form the first hole 332, and then suddenly enlarges to form the second hole 333. The stop step 334 is formed at a position at which a hoe size mutation occurs between the first hole 332 and the second hole 333.

The second hole 333 may include a rectangular shape and an arc shape that are in communication with each other. The rectangular shape is in communication with the first hole 332, and the arc shape may be, for example, a semi-circular shape. Further, the rectangular shape and the arc shape may smoothly transition. In other words, the wall of the second hole 333 is roughly smooth without an abrupt protrusion.

In some embodiments, referring to FIG. 6 and FIG. 15, an inner diameter d1 at the opening 331 may be greater than or equal to a maximum width L1 of the fixing portions 23. A maximum width L1 of the fixing portions 23 is a maximum value of a size between a pair of side walls corresponding to the limiting hole 33. For example, the fixing portion 23 may be a cylinder, and the maximum width L1 may be a diameter of the cylinder. Therefore, the fixing portion 23 can smoothly enter the first hole 332 through the openings 331.

In some embodiments, still referring to FIG. 6 and FIG. 15, an inner diameter d2 of the stop step 334 may be less than the maximum width L1 of the fixing portion 23. Therefore, after entering the second hole 333, the fixing portion 23 is limited to return to the first hole 332 to avoid that the first pipe 2 is unexpectedly disengaged from the second pipe 3, ensuring connection reliability and sealing reliability of the first pipe 2 and the second pipe 3.

In some embodiments, still referring to FIG. 6 and FIG. 15, an inner diameter d3 of the second holes 333 may be greater than or equal to the maximum width L1 of the fixing portion 23, to reliably accommodate the fixing portion 23. The inner diameter d3 of the second hole 333 may be a size of a position in which the arc region is in communication with the rectangular region.

In some embodiments, still referring to FIG. 15, a value of an included angle β between a surface of the stop step 334 facing the second hole 333 and an axial direction of the second pipe 3 may be in a range of [90°, 45°]; to ensure a good locking effect. Considering that the second pipe 3 and/or the first pipe 2 may be flexible and arranged on the thermal insulating layer 12 in a curved manner, the axial direction r in this example preferably refers to an axial direction of a nested inserting section of the first pipe 2 and the second pipe 3.

Further, a larger included angle β indicates a better effect of limiting the fixing portion 23 located at the second hole 333 to return to the first hole 332, and a better locking effect for the fixing portion 23. In FIG. 6, FIG. 12, and FIG. 15, an exemplary illustration is provided by using an example in which an included angle β=90°.

In some embodiments, still referring to FIG. 15, the included angle β between the surface of the stop step 334 facing the second hole 333 and the axial direction of the second pipe 3 may be greater than an included angle α between each of the walls of the connecting end 3a that forms the first hole 332 and the axial direction of the second pipe 3. Therefore, a disassembly force of the first pipe 2 is greater than an assembly force when the first pipe 2 is inserted into the second pipe 3 after assembly, thereby further ensuring stability of connection between the first pipe 2 and the second pipe 3.

In a specific implementation, an outer surface of the fixing portion 23 at least on a side facing the sealing rib 21 is an arc surface (or a circular surface) or an inclined surface. For example, the fixing portion 23 may be entirely in a shape a cylinder or may be an arc surface at least on a side facing the sealing rib 21, so that after the fixing portion 23 enters the second hole 333, a side of the fixing portion 23 facing the connecting end 3a may be in line contact, rather than in surface-to-surface contact, with the stop step 334. Therefore, it is avoided that the first pipe 2 and the second pipe 3 are laborious to be assembled. It is further avoided that the fixing portion 23 and the limiting hole 33 are completely locked after the first pipe 2 is inserted into the second pipe 3, so that the first pipe 2 is easily disassembled for maintenance.

Further, when the first pipe 2 is inserted into the second pipe 3 and the end portion of the connecting end 3a is tightly fitted with the sealing rib 21 to form the sealing structure, a large part of the fixing portion 23 is located in the second hole 333, and a remaining small part of the fixing portion 23 may be located in the first hole 332. Because a large part of the fixing portion 23 (especially at the maximum width L1) is limited by the stop step 334 to be located in the second hole 333, a good locking effect can be ensured.

In a variation, the fixing portion 23 may be in a shape of a cylinder of a cam, and a tip of the cam faces the first end 2a. During assembly, as the first pipe 2 is inserted into the second pipe 3, the tip of the cams may more conveniently enter the first hole 332 and the second hole 333 in sequence through the opening 331. After the first pipe 2 is assembled in position, a blunt end of the cam can more reliably match with the stop step 334, to prevent the fixing portion 23 from unexpectedly disengaging from the second hole 333. Therefore, the disassembly force of the first pipe 2 is greater than the assembly force when the first pipe 2 is inserted into the second pipe 3 after assembly, which helps reduce assembly difficulty and can take both locking reliability and a possible disassembly requirement of the first pipe 2 into consideration.

In some embodiments, a height h of the fixing portion 23 protruding outward from the outer peripheral surface of the first pipe 2 in the radial direction may satisfy the following formula: h≥0.3×t, where t is a wall thickness of the second pipe 3. Firmness is facilitated to be ensured after mounting, for example, the fixing portion 23 is prevented from disengaging from the limiting hole 33 in the radial direction.

Further, after the first pipe 2 is inserted into the second pipe 3 and is mounted in position, the fixing portion 23 may be flush with or slightly protruding from an outer surface of the second pipe 3.

In a specific implementation, referring to FIG. 13 to FIG. 15, a plurality of fixing portions 23 may be arranged at intervals in a circumferential direction of the first pipe 2, a plurality of limiting holes 33 may be provided, and the plurality of limiting holes 33 are in one-to-one correspondence with the plurality of fixing portions 23. Therefore, limiting and locking functions can be better achieved. For example, the plurality of fixing portions 23 may be evenly distributed along the circumferential direction of the first pipe 2. Correspondingly, the plurality of limiting holes 33 are evenly disposed along the circumferential direction of the second pipe 3.

FIG. 13 to FIG. 15 are exemplarily shown by using two fixing portions 23 and two limiting holes 33 as an example. The two limiting holes 33 are in one-to-one correspondence with the two fixing portions 23. As the first pipe 2 is inserted into the second pipe 3, each fixing portion 23 enters the second hole 333 of the corresponding limiting hole 33, to implement locking.

Further, the two fixing portions 23 may be symmetrically arranged along the radial direction of the first pipe 2. Therefore, the limiting and locking function is provided on two sides of the pipe in the radial direction.

In some embodiments, shapes and/or sizes of at least one fixing portion 23 among the plurality of fixing portions 23 and a corresponding limiting hole 33 may be different from shapes and/or sizes of remaining fixing portions 23 and corresponding limiting holes 33.

For example, referring to FIG. 13 to FIG. 15, the two fixing portions 23 may be cylinders having different diameters. Correspondingly, the two limiting holes 33 also have different sizes (including d1, d2, and d3). Therefore, a fool-proofing function can be achieved. For example, in some scenarios, the first pipe 2 or the second pipe 3 may be a bent pipe and have a direction limitation on a bending tendency in the box body. In this example, the fixing portion 23 and the limiting hole 33 that are arranged in pairs different from each other are configured to avoid that the first pipe 2 or the second pipe 3 is assembled reversely, thereby ensuring that the bending tendency of the first pipe 2 or the second pipe 3 after being assembled in position satisfies a requirement.

In some embodiments, a distance between the fixing portion 23 and the sealing rib 21 may be less than or equal to a distance between the limiting hole 33 and the end wall 31 of the connecting end 3a. Specifically, a distance between a center of the fixing portion 23 and the sealing rib 21 may be less than or equal to a distance between a center of the second hole 333 and the end wall 31 of the connecting end 3a. Therefore, it is ensured that the first pipe 2 is locked in a position in which the sealing rib 21 tightly engages with the end wall 31 after assembly, thereby improving reliability of the sealing structure.

Although specific implementations have been described above, these implementations are not intended to limit the scope of the present disclosure, even if only one implementation is described with respect to specific features. The feature examples provided in the present disclosure are intended to be illustrative and not limiting, unless otherwise stated. In specific implementations, the technical features of one or more dependent claims may be combined with the technical features of the independent claims, and the technical features from the corresponding independent claims may be combined in any appropriate manner, rather than only in the specific combinations listed in the claims.

Although the present disclosure is disclosed above, the present disclosure is not limited thereto. A person skilled in the art can make various changes and modifications without departing from the spirit and the scope of the present disclosure. Therefore, the protection scope of the present disclosure shall be subject to the scope defined by the claims.