A POCKET SPRING CORE FOR A MATTRESS COMPRISING BARREL SPRINGS IN THE POCKETS

Abstract

 The invention relates to a pocket spring core for a mattress, comprising barrel springs (S) in the pockets.
The core is characterised in that the external diameter of the central coil (De1) of the spring is 85mm (+/-10%), the ratio of the free length (H) of the spring to the height (h) of the core is in the range 1,3 -1,8, the ratio of the external diameter of the outermost coils (De2) to the external diameter of the central coil (De1) is less than 1, and the number of coils is 4,5-5,5.

Description

[0001] The subject of the invention is a pocket spring core for a mattress comprising barrel springs in the pockets. Various types of spring mattresses and foam mattresses are known in the art. Spring mattresses have been in use for many years. Traditional mattresses with bonnell springs (hourglass-shaped) and pocket springs, which use straight or barrel springs, are used. Pocket mattresses have the advantage that the springs, as they are not directly connected to each other (as is the case in mattresses with bonnell springs), do not interact with each other which allows the mattress to flex only at the point of pressure and adjust the deflection to the position of the body. An additional advantage of pocket springs is that the initial height of the spring is higher than the height of the pocket, and this relationship can be manipulated, thus controlling the hardness of the core. This also ensures that the pocket springs do not lose their original height because even after 40 000 cycles, the initial height of the spring does not fall below the height of the pocket. The fall is typical to bonnell springs.

[0002] In pocket mattresses, there is a principle that a mattress comprising a large number of springs with a smaller diameter will be better than one comprising fewer springs with a larger diameter. Due to the amount of material required to produce the springs and the time-consuming nature of the process, this generates very high costs when creating high-quality pocket mattress cores, plus such a mattress is relatively heavy.

[0003] A pocket mattress in which the springs are made of aluminium is known from document WO0033703A1. This mattress is lighter than a mattress with steel springs, but also less durable.

[0004] The present invention provides a pocket mattress core, with springs of increased diameter, for the production of which less material (steel) is used for the springs and less glue is used for gluing the pockets, while maintaining the hardness and strength of comparable cores with springs of smaller diameter. The purpose of using a larger diameter spring is to replace cores with smaller spring diameters, but taking into account the hardness of the mattress. The hardness of the cores according to the present invention will be similar to cores with a smaller spring mesh, both for the spring itself and for the complete core, and the functional properties of the core will be the same.

[0005] The pocket spring core for the mattress according to the invention comprises barrel springs in the pockets. The external diameter of the central coil of the spring is 85 mm (+/-10%), the ratio of the free length of the spring to the height of the core is in the range 1,3 - 1,8, the ratio of the external diameter of the outermost coils to the external diameter of the central coil is less than 1, and the number of coils is 4,5-5,5.

[0006] Preferably, the wire diameter of the spring is substantially 1,85 mm.

[0007] Also preferably, the height of the core is substantially 180 mm.

[0008] Preferably, the height of the core is 180 mm, the outer diameter of the central coil is 85 mm, the outer diameter of the outermost coils is 54 mm, the free length of the spring is 235 mm, the number of coils is 4,8, the diameter of the spring wire is 1,85 mm.

[0009] Also preferably, the core is provided with a top and bottom covering fabric.

[0010] Simply increasing the diameter of a spring has the effect of reducing its hardness and therefore the hardness of the entire pocket mattress core.

[0011] Therefore, several modifications of existing solutions were used to achieve the desired effect:

• a spring with an increased diameter of the wire from which the spring is made is used;
• a spring with a longer free length was used in relation to the height of the core;
• the number of coils has been reduced, which increases their angle of attack and thus increases the hardness.

[0012] For a core with a diameter of approximately 85 mm, a wire with a diameter 0,1-0,2 mm larger than competing products and a comparable number of coils is used. In this way, comparable performance characteristics are obtained.

[0013] The level of thermal treatment of the spring (relaxation) has been increased in the process, thanks to which the spring acquires a dark brown tarry colour - the procedure is aimed at improving the spring's resilient properties (the spring retains its original height dimensions after 50k dynamic deflection cycles) and the properties of the spring's hardness level (a high level of reheating of the wire before the coiling stage increases the spring's hardness level, which is necessary to obtain the hardness of competing products with a smaller diameter).

[0014] Another important aspect of the invention is the reduction in the number of rows along the length and width of the core. For example, the dimension: 183 cm*83 cm* 18 cm (26*12 mesh layout) based on a 71 mm diameter spring can be replaced by Q85 with the 183 cm*83 cm*18 cm (21*10 mesh layout) dimension. The 85 mm diameter mesh size is not restrictive for a single dimension of a mattress. It can be used for a wide spectrum of ranges with a height of approximately 18 cm. The core according to the invention allows the number of springs in the core to be reduced by up to 35%, depending on the size of the core. There is a reduction in energy expenditure for a core production (fewer springs per core). In addition, the amount of steel used per entire core is reduced by approximately 14% by weight. A smaller number of rows reduces the amount of glue used by a value proportional to the reduced number of rows. These are obvious environmental advantages of producing cores according to the invention.

[0015] The subject of the invention is depicted in the drawing in which fig. 1 is a schematic side view of a single pocket of the core according to the invention with a spring in it, fig. 2 is a schematic side view of the spring in its free state, fig. 3 is a simplified schematic view of the core according to the invention, fig. 4 is a simplified schematic view of a core with covering fabric.

[0016] As can be seen in fig. 3, the pocket spring core for a mattress has a standard structure, i.e. it comprises adjacent rows of springs S placed in fabric pockets. According to the present invention, the springs are barrel springs. Fig. 1 and fig. 2 denote the dimensions of the spring and pocket in the core according to the invention:

De1 refers to the outer diameter of the central coil of the spring, which in the embodiment is 85 mm (+/-10%),

De2 is the outer diameter of the outermost coils,

H is the free length of the spring,

h is the height of the core.

[0017] In the embodiment of the core according to the invention, the outer diameter of the central coil De1 of the spring is 85 mm (+/-10%), the ratio of the free length H of the spring to the height h of the core is in the range 1,3 -1,8, the ratio of the outer diameter of the outermost coils De2 to the outer diameter of the central coil De1 is less than 1, and the number of coils is 4,5-5,5.

[0018] In a preferable embodiment, the spring wire diameter is substantially 1,85 mm.

[0019] In another preferable embodiment, the height h of the core is substantially 180 mm.

[0020] In another preferable embodiment, the height h of the core is 180 mm, the outer diameter of the central coil De1 is 85 mm, the outer diameter of the outermost coils De2 is 54 mm, the free length H of the spring is 235 mm, the number of coils is 4,8, the diameter of the spring wire is 1,85 mm.

[0021] In yet another preferable embodiment, shown in fig. 4, the core is provided with a top and bottom cover fabric T.

[0022] The finished core may have different sizes and a corresponding spring arrangement, e.g. dimensions 183 cm (+/-15 cm) x 83 cm (+10 cm/-0 cm) and a pocket/spring arrangement of 21×10.

Claims

1. A pocket spring core for a mattress, comprising barrel springs (S) in the pockets, characterised in that the external diameter of the central coil (De1) of the spring is 85 mm (+/-10%), the ratio of the free length (H) of the spring to the height (h) of the core is in the range 1,3 -1,8, the ratio of the external diameter of the outermost coils (De2) to the external diameter of the central coil (De1) is less than 1, and the number of coils is 4,5-5,5

2. The core according to claim 1, characterised in that the wire diameter of the spring is substantially 1,85 mm

3. The core according to claim 1, characterised in that the height (h) of the core is substantially 180 mm

4. The core according to claim 1, characterised in that the height (h) of the core is 180 mm, the outer diameter of the central coil (De1) is 85 mm, the outer diameter of the outermost coils (De2) is 54 mm, the free length (H) of the spring is 235 mm, the number of coils is 4,8, the diameter of the spring wire is 1,85 mm

5. The core according to claim 1, characterised in that it is provided with a covering fabric (T), top and bottom.

Drawing