JP2002199963A - Backrest device for chair - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a backrest device for chair that can change to fit along the back curve of a person who is sitting leaning against a backrest the while securely supporting lumbar part of the person. SOLUTION: In this backrest device for chair, the space surrounded by a support frame 8 is filled with a number of split elements 11 arranged in matrix, whose backs are attached together with an adhesive urethane sheet and also reinforced with elastic strings 13 running from side to side to horizontally fix them. Both right and left ends of each string 13 are wound around the right or left vertical frame part of the support frame 8 and fixed on it. On the back face of the support frame 8, a lumbar support element 14 is rotatably installed at the position where the lumbar of a seated person comes so as to push those split elements 11 on the spot forward and thus give a comfortable support to the lumbar of the sitting person.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a backrest device of a chair provided with lumbar support means so that a part of the backrest portion can selectively protrude forward.

[0002]

2. Description of the Related Art Conventionally, various types of chairs having a lumbar support in which a part of a backrest portion of a chair has a waist (lumbar spine) portion of a seated person projecting forward from other back portions are known. (JP-A-57-43715,
Japanese Utility Model Publication No. 2-1075, Utility Model Registration No. 26019
06, JP-A-10-211049, etc.).

[0003]

However, in the above-mentioned conventional configuration, the cushion body of the backrest portion is formed by molding a foamed flexible polyurethane foam on the surface of the plate-like support frame. There has been a problem that the elasticity of the cushion body under the load leaning on the backrest portion is small, and the sitting comfort cannot be improved.

SUMMARY OF THE INVENTION The present invention has been made to solve such a conventional problem, and a cushion body of a backrest portion of a chair corresponds to an individual difference in body shape and weight of a person sitting on a chair. It is an object of the present invention to provide a backrest device for a chair that can elastically dent and deform and can support a lumbar spine of a seated person.

[0005]

In order to achieve the above object, a backrest device for a chair according to the first aspect of the present invention includes a backrest cushion body stretched on a support frame of a backrest portion of the chair. In a backrest device comprising lumbar support means for pushing a part of the backrest cushion body forward, the backrest cushion body straddles a plurality of divided bodies of slab urethane foam and a back surface of the plurality of divided bodies. And a plurality of elastic yarns having rubber elasticity stuck and adhered. The elastic yarns are disposed so as to extend in the frame space of the support frame in the lateral direction, and each elastic yarn is provided. Both ends of the strip are fixed to the left and right sides of the support frame so that the plurality of divided bodies are arranged in the frame space of the support frame, while the support frame has the Push a part of the divided body from the back side to selectively protrude forward It is those with a lumbar support means that.

According to a second aspect of the present invention, in the backrest apparatus for a chair according to the first aspect, the plurality of divided bodies are formed by vertically extending the support frame body in a laterally long shape in multiple stages. It is arranged in a matrix shape arranged vertically or horizontally in the frame space of the support frame body, and these multiple divided bodies are bonded and fixed with urethane film so that their back surfaces are connected to each other. is there.

[0007]

Next, embodiments of the present invention will be described. 1 is a perspective view of a chair, FIG. 2 is a perspective view of a backrest portion with a skin material removed, FIG. 3 is a perspective view of a backrest cushion body viewed from the back, and FIG. 4 is a part of the backrest cushion body. 5A is a cross-sectional view of the backrest portion in a state where no backrest load is applied, and FIG. 5B is a cross-sectional view of the backrest portion in a state of the lumbar support means where no backrest load is applied. FIG. 6 is a longitudinal sectional view of the backrest portion in a state where a backrest load is applied. FIG. 7 is a perspective view of another embodiment.

As shown in FIG. 1, a chair 1 has a backrest portion erected on a seat 3 supporting a lower portion of a seat 2 and an arm 5 projecting upward from a rear end of the seat 3. And 4. A downward supporting column 6 protrudes from the seat receiver 3, and the height of the seat body 2 can be adjusted up and down by a gas spring (not shown) disposed between the seat support 3 and a leg 7 equipped with casters.

The backrest portion 4 of the first embodiment shown in FIGS. 2 to 6 comprises a support frame 8 formed by bending a pipe made of metal or the like to form a substantially rectangular frame in a front view. A part of the backrest cushion body 9, which is arranged so as to straddle between the left and right vertical frame portions 8 a, 8 a of the support frame body 8 in the frame space of the body 8 and the backrest cushion body 9. (A portion corresponding to the lumbar spine of the seated person H) and lumbar support means 10 for selectively pushing out the front of the backrest portion 4.

Next, a first embodiment of the backrest cushion 9 will be described with reference to FIGS. The backrest cushion body 9 has a matrix shape in which divided bodies 11 obtained by dividing a flexible or semi-rigid slab urethane foam having flexibility into a substantially square block shape in a front view are arranged vertically and horizontally in a frame space of the support frame body 8. And bonded and fixed with a urethane film 12 so that the back surfaces of all the divided bodies 11 are connected to each other. Further, on the back side of the urethane film 12, a plurality of elastic thread bodies 13 of thread bodies having a rubber elasticity (refer to thread-like, string-like or narrow-band-like, the same applies hereinafter) are provided on the left and right sides of the support frame 8. The elastic filaments 13 are arranged substantially parallel to each other so as to extend in the direction, and the longitudinal middle portion of the elastic thread 13 is bonded (sticked) to the back surface of the urethane film 12 via an adhesive (see FIGS. 3 and 4). ).

The elastic thread 13 is a thermoplastic elastomer such as a thermoplastic olefin elastomer, and can be formed into a predetermined thread by injection molding or the like. At room temperature, this kind of material behaves as a rubber elastic body, but plastically deforms due to a rise in temperature. Therefore, a predetermined molded product (such as the elastic thread 13 of the present invention) is formed using a thermoplastic plastic molding machine. It is an easy-to-use polymer material.

Then, both ends of each of the elastic thread members 13 are
The support frame 8 is wound around the vertical frame portions 8a, 8a, which are both left and right portions, and fixed with an adhesive or the like.

A horizontally long lumbar support body 14 as lumbar support means 10 is eccentrically fixed to a support shaft 15 in the front-rear direction. Both ends of the support shaft 15 are connected to the vertical frame portions 8a, 8a of the support frame body 8. It is pivotally supported on brackets 16 and 16 projecting from the back (back) side. When the handle 17 at one end of the support shaft 15 is rotated in a predetermined direction, the projecting side 14a of the lumbar support body 14
The split body 11 at a predetermined height position (the height position corresponding to the lumbar spine of the person H sitting on the seat body 2) of the backrest cushion body 9 is pressed rearward (back side), and the handle 17 is moved in the reverse direction. If it rotates, the projecting side 1 of the lumbar support body 14
4 a is configured to be separated from the back surface of the divided body 11. In addition, a locking means (not shown) for locking the handle 17 at each rotation position is provided.

Further, the entire front surface of the backrest cushion 9 is covered with a skin material 19 such as a woven fabric or a synthetic leather material, and the end of the skin material 19 is wound around the support frame 8 and fixed. .

In the above construction, the bonding of the urethane film 12 keeps the divided bodies 11 arranged in a matrix so as not to fall apart. When the person H is not leaning on the backrest portion 4, as shown in FIGS. 5A and 5B, the elastic member 13 is placed in the frame space of the support frame 8 by the tension of the elastic thread 13. The plurality of divided bodies 11 are uniformly arranged in a plane without irregularities.

When the person H leans on the backrest 4, an external force in the thickness direction of the urethane film 12 acts on one or more divided bodies 11 from the surface side. In accordance with the magnitude of the external force, the divided bodies 11 adjacent to each other can be displaced and moved in the thickness direction of the divided bodies 11 while being connected by the urethane film 12. Also, the back surfaces of the divided bodies 11 adjacent to the backrest portion 4 in the left-right direction are connected to each other by the elastic thread members 13, and each elastic thread member 13 has rubber elasticity that can be greatly extended by coming off. As described above, the center portion of the wide surface of the backrest cushion body 9 (corresponding to the position where the center portion of the back of the person H strikes in the left-right direction) by the load against which the person H leans against the backrest portion 4 as described above. Is greatly displaced so as to protrude to the rear of the chair larger than the other portions, but the left and right vertical frame portions of the support frame 8 to which the end portions of the elastic thread members 13 are fixed. 8a, backrest cushion body 9 close to 8a
Is little displacement.

As described above, the divided bodies 11 arranged in a matrix are restrained to some extent by the urethane film 12, but the plurality of divided bodies 11 arranged in the lateral direction (the left-right direction of the backrest unit 4) are separated from each other. Are connected by a plurality of elastic thread members 13 which are long in the horizontal direction, so that the divided members 11 in a row corresponding to the height position corresponding to the lumbar spine portion of the seated person H and the vicinity thereof are chaired by the lumbar support members 14. 1, while being able to favorably support the lumbar portion of the seated person H (see FIG. 6), the split body 11 corresponding to the other back portion of the person H is an elastic thread body. While being elastically supported at 13, the dent can be displaced so as to well follow the curved surface of the back portion, thereby improving the sitting comfort of the chair.

In the second embodiment shown in FIGS. 7, 8 (a) and 8 (b), the divided body 2 of the backrest cushion 9 is used.
Numeral 0 denotes a block shape that is long in the left-right direction of the backrest portion 4, and the length of the backrest portion 4 is the vertical frame portions 8 on both the left and right sides of the support frame 8.
a, 8a, and the divided bodies 20 are arranged in multiple stages in the vertical direction so as to fit in the frame space of the support frame 8. Then, the back surfaces of all the divided bodies 20 are adhered by the urethane film 12 so as to be connected to each other, and furthermore, the plurality of elastic thread bodies 13 extending long in the left-right direction of the support frame 8.
Is adhered to the back surface of the urethane film 12. Since the lumbar support means 10 is the same as that of the first embodiment, the description of the configuration is omitted. Also,
An entire front surface of the backrest cushion body 9 is covered with a skin material 19 such as a woven cloth or a synthetic leather material so as to cover the surfaces of all the divided bodies 20, and an end of the skin material 19 is supported by a support frame. It is wrapped around the body 8 and fixed.

Also in the second embodiment, the horizontally long divided bodies 20 arranged in multiple stages in the upper and lower portions are formed of the urethane film 12.
However, since one divided body 20 is connected by a plurality of elastic thread bodies 13 in the lateral direction,
The heights corresponding to the lumbar vertebrae of the seated person H and the rows of divided bodies 20 in the vicinity thereof are greatly pushed forward of the chair 1 by the lumbar support body 14 to favorably support the lumbar vertebrae of the seated person H. On the other hand, since the divided body 20 corresponding to the other back portion of the person H can be dent-displaced so as to well follow the curved surface of the back portion while being elastically supported by the elastic thread body 13, The sitting comfort of the chair is improved.

When the urethane film 12 and the elastic thread 13 are adhered to the back surface of the divided body 11 (20), whichever of the urethane film 12 and the elastic thread 13 is adhered first. good.

In another embodiment, the urethane film 12 is omitted, and a plurality of elastic thread members 13 extending in the left-right direction of the backrest directly over the back surface of the divided body 11 (20). Adhesion (sticking) may be performed. In this case, a plurality of divided bodies 11 in a horizontal row (one divided body 2
0) is restrained by a plurality of elastic thread members 13 so as not to fall apart, and the upper and lower divided bodies 11
In (20), the separability which can be displaced independently of each other against an external force from the front-back direction of the backrest portion 4 is enhanced. Therefore, only the divided body 11 (20) of the portion pushed forward by the lumbar support body 14 is pushed greatly forward of the chair 1, and the lumbar spine portion of the seated person H can be further supported.

The lumbar support means may be mounted separately from the support frame 8 on a support member erected on the rear side of the seat 2, or may be attached to the seat 2 at the time of backrest. In a so-called locking mode in which the support frame 8 can be tilted rearward, the lumbar support means may be of a type in which the lumbar support means relatively moves forward in the frame space of the support frame 8 during the locking. Further, the amount of the lumbar support body projecting forward in the lumbar support means may be configured to be adjustable.

[0023]

As described above, the backrest device for a chair according to the first aspect of the present invention includes a backrest cushion body stretched on a support frame of a backrest portion of the chair, and the backrest cushion. In a backrest device including lumbar support means for pushing a part of the body forward, the backrest cushion body is attached to a plurality of divided bodies of slab urethane foam and over the back surfaces of the plurality of divided bodies. A plurality of elastic yarns having rubber elasticity attached thereto, the elastic yarns are disposed so as to extend long in the lateral direction within the frame space of the support frame, and each elastic yarn Both ends are fixed to the right and left sides of the support frame so that the plurality of divided bodies are arranged in the frame space of the support frame. On the other hand, the support frame includes Lumbar that pushes part from the back side and selectively protrudes forward Those having a port means.

[0024] With this configuration, the backrest cushion body is connected by a plurality of elastic thread bodies having rubber elasticity which are stuck on the back surfaces of the plurality of divided bodies of the slab urethane foam, and Since the ends of each elastic thread are fixed to the right and left sides of the support frame, each of the divided bodies is elastically supported by the elasticity of the elastic thread, so that the divided body rests on the backrest. The backrest cushion body can be elastically deformed favorably along the cross-sectional shape of the back of the person, and the lumbar support means can push out only the divided part corresponding to the lumbar part of the person to the front of the chair. The effect is that the lumbar region of a person can be firmly supported.

According to a second aspect of the present invention, in the backrest device for a chair according to the first aspect, the plurality of divided bodies are formed by vertically extending the support frame body in a horizontally long shape in a multi-stage manner. It is arranged in a matrix shape arranged vertically or horizontally in the frame space of the support frame body, and these multiple divided bodies are bonded and fixed with urethane film so that their back surfaces are connected to each other. Yes. The plurality of horizontally divided bodies or the plurality of divided bodies arranged in a matrix are restrained to some extent by the urethane film,
Since the horizontal row of divided bodies are connected by a plurality of elastic filaments which are long in the lateral direction, the height position corresponding to the lumbar vertebra part of the seated person and the divided bodies in the vicinity thereof are chairs by the lumbar support means. Can be well pushed forward to support the lumbar portion of the seated person, while the divided body corresponding to the other back portion of the person is elastically supported by the elastic filament while the back Since the dent can be displaced so as to follow the curved surface of the portion, the sitting comfort of the chair is improved.

[Brief description of the drawings]

FIG. 1 is a perspective view of a chair.

FIG. 2 is a perspective view of a backrest portion.

FIG. 3 is a perspective view showing a rear surface side of a divided body arranged in a matrix.

FIG. 4 is a partially enlarged cross-sectional view taken along line IV-IV of FIG. 3;

5A is a sectional view taken along line Va-Va of FIG. 2, and FIG. 5B is a sectional view taken along line Vb-Vb of FIG.

FIG. 6 is a cross-sectional view showing a state in which a lumbar support body pushes and supports a human lumbar spine portion forward.

FIG. 7 is a perspective view of a backrest according to a second embodiment.

8A is a sectional view taken along line VIIIa-VIIIa in FIG. 7;
(B) is a sectional view taken along line VIIIb-VIIIb in FIG. 2.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Chair 4 Backrest part 8 Support frame body 8a, 8a Vertical frame part 9 Backrest cushion body 10 Lumbar support means 11 Split body 12 Urethane film 13 Elastic thread body 10 Lumbar support means 14 Lumbar support body

Claims (2)

[Claims] 1. A backrest device comprising a backrest cushion body stretched on a support frame of a backrest portion of a chair, and lumbar support means for pushing a part of the backrest cushion body forward. The back cushion body is composed of a plurality of divided bodies of slab urethane foam, and a plurality of elastic thread bodies having rubber elasticity stuck over the back surfaces of the plurality of divided bodies. The plurality of divided bodies are disposed so as to extend in the lateral direction within the frame space of the support frame, and both ends of each elastic thread are fixed to both left and right portions of the support frame. While being configured to be arranged in the frame space of the frame, the support frame includes lumbar support means for pressing a part of the divided body from the back side and selectively projecting forward. A backrest device for a chair. 2. The plurality of divided bodies are arranged in a vertically long and horizontally tiered manner in the support frame body in a horizontally long shape which is long in the left-right direction, or arranged in a matrix in which the support frame body is arranged vertically and horizontally in a frame space of the support frame body. The backrest device for a chair according to claim 1, wherein the plurality of divided bodies are bonded and fixed with a urethane film so that the back surfaces thereof are connected to each other.