JP7429453B2 - Buffer material and cushion body for coil springs - Google Patents

Description

The present invention relates to a coil spring cushioning material used in a cushion body such as a mattress, a sofa, a seat, or a chair, and a cushion body including the coil spring cushioning material.

BACKGROUND ART Mattresses with a built-in spring unit in which coil springs spread over substantially the entire surface have been known as mattresses with good cushioning properties (Patent Document 1, Patent Document 2). Pocket coils, Bonnell coils, and the like are known as coil springs.

In general, conventional cushion bodies such as mattresses and sofas have a spring unit (spring structure) consisting of a large number of coil springs, and a cushioning material as a spring receiver is placed on the top and bottom surfaces of the spring unit. It is constructed by polymerizing an elastic material such as a sheet or a sheet made of polyester cotton material and covering it with an exterior material as necessary. The role of the cushioning material is mainly to prevent urethane sheets, polyester cotton sheets, etc. from being torn or dented by the coil springs, such as palm mats (palm pads), palm felt, needle felt. , cotton felt, and hard felt are used.

Japanese Patent Application Publication No. 8-38312 JP2018-33860A

By the way, all the palm mats (palm pads) currently used in Japan are imported from overseas. Only the coconut shell part is extracted from the palm fruit, and it is then compressed for import before being transported. Once the coconut shells arrive in Japan, they are transported to a factory where they are loosened and shaped into mats. Needle punching is performed during molding, but the needles are surprisingly frequently damaged during this process, making needle inspection essential.

The use of coconut shell mats (palm pads) has the following problems.
Because we rely on imports from overseas, it is difficult to secure a stable supply and it takes time to transport them. Additionally, since it is a natural product, there may be variations in the product, and there may be insects, dirt, etc. mixed in. Also, the speed of deterioration is fast. It takes time and effort to perform meter reading work. Because it is a short fiber, it easily generates debris and dust. It is difficult to bend and is difficult to use for roll-type or reclining mattresses for nursing care beds. Because it absorbs moisture, it tends to accumulate moisture and become unsanitary. It cannot be recycled and must be incinerated.

On the other hand, when using felt materials such as needle felt, cotton felt, and hard felt, the material absorbs moisture, which tends to accumulate moisture and cause dust mites and mold.If you continue to use it, it will be pushed by the spring and gradually There are problems such as a drop in buffering performance.

In addition, if you use coconut shell mat (palm pad), palm felt, needle felt, cotton felt, or hard felt as a cushioning material for coil springs, you can use urethane to make a soft mat. It is necessary to adjust the softness by changing the thickness and density of the elastic body such as a sheet or cotton sheet, and there is a problem in that the number of parts increases in order to provide variations in hardness.

Therefore, in the present invention, instead of conventionally used palm mats (palm pads), felt, etc., a three-dimensional network structure made of thermoplastic resin is used as a cushioning material for coil springs, thereby stabilizing the supply of cushioning material products. To provide a cushioning material for coil springs that has improved cushioning performance, good air permeability, and can reduce the number of parts required for manufacturing cushion bodies such as mattresses and sofas, and to provide cushion bodies using this cushioning material. For the purpose of providing.

In order to solve the above-mentioned problems, the present invention is used inside a cushion body that incorporates multiple stages of spring structures including coil springs, and is arranged between the overlapping spring structures, and has a continuous filament of thermoplastic resin. It consists of a three-dimensional network structure having a thickness of 0.5 to 300 mm and a bulk density of 0.01 to 0.9 g/ ^cm3 , in which loops are formed by irregularly partially welding the three-dimensional network structure. The structure is a shock absorbing material for a coil spring, which has a surface layer on at least one surface in the extrusion direction, and the bulk density of the surface layer is larger than the bulk density of a portion excluding the surface layer .

According to this, the three-dimensional network structure functions as a buffer material for the spring structure, and products can be stably supplied. It also prevents the springs from coming into direct contact with each other, improving functionality, reducing noise, and protecting parts. Furthermore, it is possible to provide a cushion body that has good air permeability and is resistant to mold and the like. Examples of the "cushion body" include mattresses, sofas, chairs, and seats in vehicles. In addition, the surface layer, which is a high-density layer, serves as a cushioning material and a spring holder, and the portion other than the surface layer can have cushioning properties. That is, the portion excluding the surface layer can function as a urethane sheet conventionally used on felt or palm pads.

Further, the present invention is used inside a cushion body that incorporates multiple stages of spring structures including coil springs, and is arranged between the overlapping spring structures, and continuous filaments of thermoplastic resin are arranged irregularly and partially. It consists of a three-dimensional network structure with a thickness of 0.5 to 300 mm and a bulk density of 0.01 to 0.9 g/cm3, which is formed into a loop by welding to the ^extrusion direction. The cushioning material for a coil spring has a surface layer on both sides, and the bulk density of the surface layer is larger than the bulk density of a portion excluding the surface layer.

The thickness of the surface layer is 0.3 to 9 mm, the bulk density of the surface layer is 0.1 to 0.8 g/cm ³ , and the bulk density of the portion excluding the surface layer is 0.03 to 0. .3 g/cm ³ is preferred.

Furthermore, the present invention is used inside a cushion body that incorporates multiple stages of spring structures including coil springs, and is arranged between the overlapping spring structures, and continuous filaments of thermoplastic resin are irregularly partially formed. A loop is formed by welding to ³ The three-dimensional network structure is a cushioning material for a coil spring, and the three-dimensional network structure has a sparse and dense structure in which bulk density portions and dense portions alternate in the extrusion direction. According to this, the three-dimensional network structure is easily bent in the extrusion direction (namely, the longitudinal direction of the mattress), so it can be applied to various mattresses such as reclining type and roll type.

The three-dimensional network structure preferably has a maximum load of 1 to 30 kgf in a tensile test in the extrusion direction. According to this, it is possible to ensure sufficient cushioning performance and strength as a spring cushioning material while transmitting the spring characteristics of the spring structure.

It is preferable that the three-dimensional network structure has a sparse and dense structure in which portions with a bulk density and portions with a bulk density alternately appear in the extrusion direction.

According to this, the three-dimensional network structure is easily bent in the extrusion direction (namely, the longitudinal direction of the mattress), so it can be applied to various mattresses such as reclining type and roll type.

Further, the present invention is a cushion body including the above-described shock absorbing material for a coil spring.

The three-dimensional network structure preferably has a thickness of 1 to 10 mm.

According to this, sufficient buffering performance can be ensured as a spring receiver for a spring coil.

The three-dimensional network structure preferably has a thickness of 15 to 60 mm.

According to this, the three-dimensional network structure also serves as a cushion layer, and the urethane sheet or the like disposed on the top surface thereof can be omitted.

According to the present invention, the shock absorbing performance of the coil spring can be improved, and the durability of the shock absorbing performance can also be improved. It also prevents the springs from coming into direct contact with each other, improving functionality, reducing noise, and protecting parts. In addition, changing the hardness of the three-dimensional network structure can affect the hardness of cushion bodies such as mattresses, so the number of parts required for cushion bodies of current mattresses, etc. It is possible to reduce the number of points. Additionally, it has good breathability and is easy to bend, making it possible to provide mattresses that can be used with a variety of beds. Furthermore, since the fusion strength between the thermoplastic resin fibers can be kept constant, there is little variation in the cushioning performance of the product. In addition, it becomes possible to recycle the cushioning material, and it becomes easy to separate it from other materials when recycling cushioning bodies such as mattresses. There is no need to worry about contamination with insects or dirt, a stable supply of products is possible, and there is no need for meter reading.

1 is a schematic cross-sectional view showing a cross-sectional structure of a mattress according to a first embodiment of the present invention. It is a photograph of a three-dimensional network structure as a cushioning material in a 1st embodiment of the present invention. It is a cross-sectional photograph showing a laminated state of a three-dimensional network structure and a spring structure in a first embodiment of the present invention. It is a photograph of a modified example of the three-dimensional network structure as a cushioning material in the first embodiment of the present invention. It is a schematic sectional view showing the cross-sectional structure of the mattress in a 2nd embodiment of the present invention.

Referring to FIGS. 1 to 4, a three-dimensional network structure 4, which is a mattress 1 and a first coil spring cushioning material (hereinafter referred to as a first cushioning material) according to a first embodiment of the present invention, will be described. As shown in FIG. 1, a mattress 1 as a cushion body includes, from above, a covering material 2, a urethane sheet 3, a three-dimensional network structure 4 as a first cushioning material, and a spring structure including a plurality of coil springs 5a. 5. This is a laminate in which a three-dimensional network structure 6 as a second shock absorbing material for a second coil spring (hereinafter referred to as a second shock absorbing material) and a facing material 7 are stacked.

As shown in FIGS. 1 and 3, the three-dimensional network structure 4 serving as the first buffer material is arranged so as to be in contact with the upper surface of the spring structure 5, and serves as a spring holder for the coil spring 5a. Fulfill. As shown in FIG. 2, the three-dimensional network structure 4 has loops formed by irregularly and partially welding continuous filaments of thermoplastic resin, and preferably has a thickness of 0.5 mm or more. is in the form of a sheet of 1 to 10 mm, more preferably 3 to 7 mm. The extrusion direction during manufacturing is the longitudinal direction, and the direction perpendicular to the extrusion direction is the transversal direction. As raw material thermoplastic resins, polyethylene thermoplastic resins, polypropylene thermoplastic resins, polyester thermoplastic elastomers, polypropylene thermoplastic elastomers, mixtures of polyethylene thermoplastic resins and polyethylene thermoplastic elastomers, PVC, etc. It is preferable to include.

The three-dimensional network structure 4 as a first cushioning material plays the role of a spring holder for the coil spring 5a, transmitting the spring characteristics of the coil spring 5a upward, and is a surface disposed on the top surface of the three-dimensional network structure 4. This suppresses tearing and denting of the material 2 and the urethane sheet 3 due to the spring, and further suppresses the user from feeling discomfort or pain due to the hardness of the coil spring 5a. In addition, when the thickness of the three-dimensional network structure 4 is 1 cm or more, the three-dimensional network structure 4 also serves as a cushion layer, as will be explained in the second embodiment described later.

The continuous filaments constituting the three-dimensional network structure 4 may have either an irregular shape or a hollow shape. The diameter of the continuous filament is an important factor in obtaining cushioning performance and soft cushioning properties, and the diameter of the continuous filament is preferably 0.5 mm to 3 mm. If the wire diameter is smaller than the above range, the wires are likely to break, while if the wire diameter is too large, it will cause damage to the urethane, skin layer, etc. fibers arranged on the three-dimensional network structure 4. Therefore, it is necessary to set it within an appropriate range. The wire diameter is determined by cutting out a resin thread from the center of the sample, measuring the thickness of the resin thread five times with a caliper, and taking the average of the measured values.

The three-dimensional network structure 4 preferably has a bulk density (apparent density) of 0.01 g/cm ³ to 0.9 g/cm ³ . If the bulk density is too low, the buffering performance of the spring will be insufficient, and if the bulk density is too high, it will be difficult to bend. Note that the thickness and bulk density of the three-dimensional network structure 4 described above are measured as follows. Cut the sample into a size of 30 cm x 30 cm, leave it unloaded for 24 hours, measure the height at 4 places, take the average value as the sample thickness, calculate the volume from the sample thickness, and calculate the weight of the sample in terms of volume. The divided value is measured as the bulk density of the sample.

The three-dimensional network structure 4 preferably has a maximum load (maximum yield strength) in the extrusion direction during manufacture of 1 to 30 kgf, preferably 2 to 30 kgf, in a tensile test to be described later. If the maximum load in the tensile test is less than 2, the fusion between the fibers may come off during compression, and if the maximum load in the tensile test is greater than 30 kg, it will be difficult to convey the spring characteristics. The maximum load in the extrusion direction is influenced by fineness, bulk density, raw material, and structure.

The above tensile test is performed as follows.
A test piece is a 10 cm (length: extrusion direction) x 10 cm (width) cut from the three-dimensional network structure product, the upper end of the test piece is fixed, and the test piece is placed at a position 4 cm above the lower end of the center in the width direction of the test piece. The maximum load is measured by hooking a hook with a diameter of 5 mm and R20 and pulling it downward.

The hardness of the three-dimensional network structure 4 can be adjusted by changing the fineness, bulk density, raw material, and structure. By changing the hardness, the hardness of the entire mattress can be adjusted without changing the density or thickness of the urethane sheet 3 and the covering material 2 placed thereon.

It is preferable that the three-dimensional network structure 4 has a sparse and dense structure in which portions of coarse bulk density and portions of dense bulk density appear alternately in the extrusion direction (longitudinal direction of mattress 1) during manufacturing. By providing a sparse and dense structure, the ease of bending in the extrusion direction is improved, making it possible to apply it to mattresses for various purposes such as reclining nursing care beds and roll types.

The three-dimensional network structure 4 shown in FIGS. 2 and 3 is a planar sheet, but as shown in FIG. 4, a three-dimensional network structure 4 that is wavy in side view is also applicable.

The spring structure 5 includes a plurality of coil springs 5a. For the coil spring 5a, any spring member can be used, such as a connected type like a Bonnell coil, a continuous type like a super lastic coil, or an independent type like a pocket coil. can.

As shown in FIG. 1, the three-dimensional network structure 6 serving as the second cushioning material is arranged so as to be in contact with the lower surface of the spring structure 5. The structure of the three-dimensional network structure 6 is the same as the three-dimensional network structure 4. As the second cushioning material, in addition to the three-dimensional network structure, it is also possible to use felt, nonwoven fabric, urethane, or sponge.

The urethane sheet 3 is arranged so as to be in contact with the upper surface of the three-dimensional network structure 4. The urethane sheet 3 is a highly air permeable urethane sheet with a thickness of 0.5 cm to 5 cm.

The facing materials 2 and 7 cover the other laminates of the mattress 1, and are laminated with conventionally used cushioning fabrics such as tricot fabrics, knit fabrics, urethane fabrics, and non-woven fabrics, and are quilted. You can use anything you like. You may use substances that have deodorizing, antibacterial, and anti-mite effects.

In this embodiment, the urethane sheet 3, the three-dimensional network structure 4, the spring structure 5, and the three-dimensional network structure 6 are assembled into a laminate by engaging their respective side edges with engagement members. do. The mattress 1 is manufactured by covering the entire laminate with the facing materials 2 and 7.

In the present invention, since the three-dimensional network structure 4 functions as a buffer material and a spring receiver for the coil spring 5a of the spring structure 5, a palm pad or a No need for felt. This enables a stable supply of products and improves cushioning performance and durability compared to conventional palm pads and felt.

Furthermore, since changing the hardness of the three-dimensional network structure 4 can affect the hardness of the mattress 1, it is possible to reduce the number of parts required for current mattresses, such as the number of urethane sheets and cotton sheets. I can do it.

A detailed method for manufacturing the three-dimensional network structures 4 and 6 used in the present invention is described in Japanese Patent No. 4350286 and U.S. Pat. S. Patent No. No. 7,625,629, etc., please refer to the patent applicant's publications. The above-mentioned sparse and dense structure in the extrusion direction is basically formed by varying the speed of the rollers or caterpillars.

Next, referring to FIG. 5, a mattress 101 and a cushioning material according to a second embodiment of the present invention will be described. Since this mattress 101 basically has the same configuration as the mattress 1, common explanations will refer to the illustrations and descriptions of the first embodiment, and differences will be explained. The numbers assigned to each element correspond to the numbers in the 100s in the first embodiment. In the second embodiment, a three-dimensional network structure 104 as a first buffer material and a three-dimensional network structure 106 as a second buffer material are respectively provided with high-density surface layers 104a and 106a. This embodiment differs from the first embodiment in that a urethane sheet, which is an elastic body, is not provided on the upper surface of the structure 104.

The mattress 101 includes, from above, a facing material 102, a three-dimensional network structure 104 as a first cushioning material, a spring structure 105 including a plurality of coil springs 105a, a three-dimensional network structure 106 as a second cushioning material, and This is a laminate in which facing materials 107 are laminated.

The three-dimensional network structure 104 as the first buffer has a thickness of 30 cm or less, preferably 1.5 to 6 cm, and more preferably 2 to 4 cm. The bulk density is preferably 0.025 to 0.9 g/cm ³ . Among them, at least one surface in the extrusion direction during manufacturing is provided with a surface layer 104a having a thickness of 0.3 to 9 mm, the surface layer 104a has a larger bulk density than the inner part 104b excluding the surface layer 104a, and the surface layer 104a The bulk density of the inner portion 104b is preferably 0.1 to 0.8 g/cm ³ , and the bulk density of the inner portion 104b is preferably 0.03 to 0.3 g/cm ³ . In this embodiment, the surface layer 104a is formed only on one side in the extrusion direction, and the other side is the inner part 104b. The three-dimensional network structure 104 is arranged so that the surface layer 104a is on the bottom surface. That is, the three-dimensional network structure 104 is arranged so that the surface layer 104a is in contact with the upper surface of the spring structure 105. The surface layer 104a is formed by adjusting the density of the number of holes per unit area and/or the size of the diameter of the holes of the cap or by providing a chute above the water tank in the method for manufacturing the three-dimensional network structure described above. be done.

In the three-dimensional network structure 104, the surface layer 104a with high bulk density mainly contributes to high spring receiving performance, and the inner part 104b with low bulk density contributes to cushioning properties. In this embodiment, the urethane sheet is omitted because the three-dimensional network structure 104 has high cushioning properties, but a urethane sheet may be laminated on the three-dimensional network structure 104 to further improve the cushioning properties. good.

In this embodiment, the three-dimensional network structure 104 achieves high cushioning properties, but by adjusting the repulsion force and hysteresis loss of the three-dimensional network structure 104, it can be used as a soft type, regular type, hard type, etc. You can adjust the sleeping comfort. Repulsion force and hysteresis loss can be adjusted by changing the structure, bulk density, raw material, thickness of the surface layer, and thickness of the structure.

The three-dimensional network structure 106 as the second cushioning material also has the same configuration as the three-dimensional network structure 104. The three-dimensional network structure 106 is arranged so that the surface layer 106a is the upper surface. That is, the surface layer 106a is arranged so as to be in contact with the lower surface of the spring structure 105, and serves as a spring receiver.

Although the first and second embodiments have been described above, the present invention can be modified and added to various forms as appropriate without departing from the spirit of the present invention. For example, in the first and second embodiments, on the top and bottom surfaces of the three-dimensional network structures 4 and 104 as the first buffer, and on the top and bottom surfaces of the three-dimensional network structures 6 and 106 as the second buffer, Another sheet such as a nonwoven fabric may be laminated.

In the first and second embodiments, the three-dimensional network structure 4, 104 is used in the mattress 1, 101, but it is also used in the seat of a sofa, chair, vehicle, etc., or other cushion body that has a built-in spring structure. May be used. Furthermore, in the first embodiment, the three-dimensional network structure 4 may include a surface layer with high bulk density and be disposed on the spring structure side. Furthermore, in the second embodiment, the three-dimensional network structure 104 does not need to be provided with the surface layer 104a, or may be provided with the surface layers 104a on both surfaces.

Furthermore, it is also possible to insert a cushioning material made of a three-dimensional network structure into the upper and lower surfaces of two or more stacked coil springs such as integrated springs and pocket coils, or between multiple coil springs. be. This prevents the springs from coming into direct contact with each other, improving functionality, reducing noise, and protecting parts. When a cushioning material made of a three-dimensional network structure is arranged between a plurality of coil springs, it is also preferable to provide surface layers on both sides.

1, 101... Mattress 2, 102... Covering material 3... Urethane sheet 4, 104... Three-dimensional network structure 104a... Surface layer 104b... Inner part 5, 105... Spring structures 5a, 105a... Coil springs 6, 106... Three-dimensional network structures 7, 107... Covering material

Claims (7)

It is used inside a cushion body that has multiple stages of spring structures including coil springs.
disposed between the overlapping spring structures;
A three-dimensional network structure with a thickness of 0.5 to 300 mm and a bulk density of 0.01 to 0.9 g/ ^cm3 , in which loops are formed by irregularly and partially welding continuous filaments of thermoplastic resin. The three-dimensional network structure has a surface layer on at least one side in the extrusion direction, and the bulk density of the surface layer is larger than the bulk density of the part excluding the surface layer.
Cushioning material for coil springs. It is used inside a cushion body that has multiple stages of spring structures including coil springs.
disposed between the overlapping spring structures;
A three-dimensional network structure with a thickness of 0.5 to 300 mm and a bulk density of 0.01 to 0.9 g/cm3, in which ^loops are formed by irregularly and partially welding continuous filaments of thermoplastic resin. The three-dimensional network structure has a surface layer on both sides in the extrusion direction, and the bulk density of the surface layer is larger than the bulk density of the part excluding the surface layer .
Cushioning material for coil springs. The thickness of the surface layer is 0.3 to 9 mm, the bulk density of the surface layer is 0.1 to 0.8 g/cm ³ , and the bulk density of the portion excluding the surface layer is 0.03 to 0. .3g/ ^cm3 ,
The buffer material for a coil spring according to claim 1 or 2 . It is used inside a cushion body that has multiple stages of spring structures including coil springs.
disposed between the overlapping spring structures;
A three-dimensional network structure with a thickness of 0.5 to 300 mm and a bulk density of 0.01 to 0.9 g/cm3, in which ^loops are formed by irregularly and partially welding continuous filaments of thermoplastic resin. The three-dimensional network structure has a sparse and dense structure in which bulk density portions and dense portions alternate in the extrusion direction.
Cushioning material for coil springs. The buffer material for a coil spring according to any one of claims 1 to 4 , wherein the three-dimensional network structure has a maximum load in a tensile test of 1 to 30 kgf in the extrusion direction. The buffer for a coil spring according to any one of claims 1 to 3 , wherein the three-dimensional network structure has a sparse and dense structure in which portions with a bulk density and portions with a bulk density alternately appear in an extrusion direction. Material. A cushion body comprising the coil spring cushioning material according to any one of claims 1 to 6.

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