JP2009112360A - Backrest of chair - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a backrest capable of providing a sense of comfort by bending the upper and lower parts of stretching material rearward with appropriate flexibilities different from each other. <P>SOLUTION: In the backrest 10 of the chair, the meshed or woven stretching material 14 is stretched over an upper frame 12, which has an inverted U-shape when viewed from the front, of a back frame. A part to support the back of a seated person at the upper part of the stretching material 14 is a low-density part 23 with a rough mesh, and at least part in the vertical direction of a part to support the waist region of the seated person at the lower part of the stretching material is a high-density part 24 with a mesh finer than that at the upper part of the stretching material 14. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a backrest of a chair in which an elastically deformable tension material is stretched on a back frame.

As a backrest of this type of chair, for example, there are those described in Patent Documents 1 and 2.
JP 2003-135200 A JP 2006-94995 A

In the backrest of a chair with upholstery, the amount of deflection of the upholstery when the seated person leans on the backrest is higher than the lower side that supports the lower back. It is preferable to enlarge the upper side that supports the seat because a comfortable sitting comfort is obtained.
However, in the backrest of the chair described in Patent Document 1, since the mesh-like upholstery material knitted to a uniform density is stretched over the back frame that forms a frame shape, the upholstery material If the lower part of the upper part is set to an appropriate amount of deflection, the upper side will be greatly bent backwards. Conversely, if the upper part of the upholstery material is set to an appropriate amount of bending, the lower part will be bent too much. I can't get comfort.

  In the backrest described in Patent Document 2, a belt-like mesh portion (low elastic portion) facing left and right is formed on the entire surface of the fabric constituting the upholstery material (backrest sheet body). Since the upper and lower are arranged alternately in the vertical direction, the amount of bending of the entire tension material is substantially uniform, and the amount of bending to the rear on the upper side compared to the lower side It is not possible to improve the sitting comfort by increasing the size.

  The present invention has been made in view of the above problems, and the back and the back of the upholstery material so that the upper part and the lower part of the upholstery bend backward with an appropriate amount of flexure different from each other. It is intended to provide.

According to the present invention, the above problem is solved as follows.
(1) In a backrest of a chair formed by stretching a knitted or woven upholstery material on an upper frame of the back frame that is U-shaped downward in front view, a seat on the upper side of the upholstery material The part supporting the back of the person is a low density part with a coarse mesh, and at least a part of the part supporting the vicinity of the waist in the lower part in the vertical direction is finer than the upper part of the upholstery material. Part.

(2) In the above item (1), the left and right side bars in the upper frame are bent in a square shape so that the lower part in the vertical direction protrudes forward, and above the bent part. While setting it as a low density part, let at least one part of the up-down direction below a bending part be a high density part.

(3) In the above item (1) or (2), it is assumed that the lower portion of the upholstery material is arranged with high density portions and low density portions alternately in the vertical direction.

(4) In the above item (3), the high-density part and the low-density part at the lower part of the upholstery material are band-shaped in the left-right direction.

(5) In any one of the above items (1) to (4), the upholstery material is made into one mesh, and the downward U-shaped bag-like portion provided on the outer peripheral edge thereof is inserted into the upper frame to make the tension. Set up.

According to the first aspect of the present invention, the portion that supports the back of the occupant in the upper portion of the upholstery material is a low density portion having a coarse mesh density, and at least a portion in the vertical direction of the portion that also supports the vicinity of the waist portion in the lower portion. Since the high density portion is smaller than the density of the upper portion, the upper portion and the lower portion of the upholstery material bend with an appropriate amount of deflection different from each other. That is, the amount of bending of the upper portion of the upholstery material is larger than that of the lower portion, and the bending amount is greatly bent backward with a smaller load than that of the lower portion.
Therefore, for example, even when the lower part of the tension member is set to a small deflection amount so as to have a lumbar support function, the deflection amount of the upper part of the tension member can be increased, so that a comfortable sitting comfort can be obtained.

  According to the second aspect of the present invention, the amount of bending of the portion supporting the back can be increased while enhancing the lumbar support effect of the portion supporting the vicinity of the lumbar portion of the seated person, so that a more comfortable sitting comfort can be obtained.

  According to invention of Claim 3, the amount of bending of the lower part of a tension material can be adjusted moderately.

  According to the invention of claim 4, the waist portion is comfortably supported by the high density portion and the low density portion which are formed in a band shape, and the high density portion and the low density portion are alternately arranged in the vertical direction. Therefore, it can provide an excellent backrest in terms of design.

  According to the invention described in claim 5, since the tension material is in the form of one mesh, the tension materials having different upper and lower densities can be easily manufactured by machine knitting, machine weaving, etc., and the material cost Can also be saved, so the cost can be reduced.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view of a chair provided with the backrest of the present invention, FIG. 2 is a front view thereof, and FIG. 3 is an exploded perspective view of the backrest.

The leg 1 of the chair has five legs 2 that have gas springs (not shown) for height adjustment accommodated therein, and that are fixed to the upper outer peripheral surface thereof and that have casters 3 at the front end thereof and that face in the radial direction. The seat body 6 is attached to the upper part of the support base 5 attached to the upper part of the pedestal 2.
The seat body 6 is composed of a seat plate 7 made of synthetic resin and a cushion material 8 attached to the upper surface of the seat plate 6, and armrests 9, 9 whose upper ends are bent outward are formed on both side edges of the seat plate 7. It is connected continuously.

The backrest 10 includes a back frame 13 including a lower frame 11 and an upper frame 12, and a tension member 14 stretched on the back frame 13.
The lower frame 11 is formed by bending a metal pipe into a U-shape upward when viewed from the front, so that short upper side bars 11b and 11b are connected to both ends of the horizontal bar 11a. Connecting rods 15 and 15 having a smaller diameter are fitted to the opposite side flange 11b so as to protrude upward, and set screws (not shown) inserted through upper and lower mounting holes 16 on the front surface of the upward side flange 11b. ).

  A pair of left and right mounting brackets which are attached to the lower surfaces of both sides of the rear end portion of the seat plate 7 and are L-shaped inward when viewed from the front, on the front surface of the connecting corner portion of the horizontal rod 11a and the upward side rod 11b. The rear ends of 17 and 17 are fixed by welding so as to face forward.

  The upper frame 12 bends a metal pipe having the same outer diameter as that of the lower frame 11 in a downward U shape so that the lower part is slightly outwardly opened when viewed from the front, and is slightly more than the central part in the vertical direction. It is formed by bending so that the lower part protrudes forward so as to form a substantially square shape when viewed from the side, and the lower ends of the left and right downward side rods 12a, 12a are connected to the left and right connecting rods 15 of the lower frame 11, respectively. , 15, and the set screw 19 inserted from the mounting hole 18 provided in the inner surface of the lower end portion of the downward-side flange 12a is screwed into the female screw hole 20 on the inner surface of the connecting rod 15 and fixed. A back frame 13 having a rectangular frame shape when viewed from the front is formed.

  The upholstery material 14 is formed into a rectangular shape by knitting or weaving synthetic fibers having high tensile strength and appropriate stretchability, such as polyamide fiber or polyester fiber, into a single mesh shape. The left and right dimensions before stretching are smaller than the left and right dimensions of the back frame 13, and the vertical dimension is longer than that of the back frame 13.

The left and right dimensions of the lower end portion of the upholstery material 14 are gradually reduced downward by obliquely cutting out both corners of the lower end portion.
A bag-like portion 21 facing in the left-right direction and a downward U-shaped bag-like portion 22 inserted through the upper frame 12 are respectively provided on the lower edge of the upholstery material 14 and the outer peripheral edge excluding the lower end portion. And are formed.

The upper half portion of the upholstery material 14 surrounded by the bag-like portion 22, that is, the upper portion of the lower side collar 12a that supports the upper part of the back of the seated person, is a mesh eye. The rough low density portion 23 is formed.
Further, in the lower part of the upholstery material 14 located below the bent part of the downward-side saddle 12a, that is, the part supporting the vicinity of the waist from the lower part of the back of the seated person, the coarser mesh finer than the mesh of the upper half part. The plurality of high-density portions 24 and the plurality of low-density portions 23 having the same roughness as the meshes of the upper half are alternately formed in the vertical direction and in a strip shape in the left-right direction.
The roughness of the mesh of the lower end part of the upholstery material 14 and the bag-like parts 21 and 22 is set to a high density in order to ensure the tensile strength.

Next, the assembly procedure of the backrest 10 will be described with reference to FIGS.
Before connecting the lower frame 11 and the upper frame 12, first, the tension member 14 is temporarily attached to the upper frame 12 as follows.
As shown in FIG. 3, slit-like openings 25, 25 facing in the vertical direction are formed on the inner front surfaces of the left and right lower ends of the bag-like portion 22 on the outer peripheral edge of the upholstery material 14, as shown in FIG. 4. As described above, while inserting the end portion of either the left or right downward side rod 12a from either one of the openings 25, and pulling the entire tension material 14 toward the other downward side rod 12a, the downward side rod The end of 12 a is projected from the other opening 24. At this time, since the left and right dimensions of the upholstery material 14 are smaller than the left and right dimensions of the upper frame 12, the tension material 14 is pulled in the left and right directions to apply tension.

  Next, the lower end portions of the left and right downward side rods 12a are fitted and fixed to the connecting rods 15 of the lower frame 12 in the manner described above, and the lower frame 11 and the upper frame 12 are connected.

  Next, a fixing plate 26 facing in the left-right direction is inserted into the bag-like portion 21 at the lower edge of the upholstery material 14, and the front surface of the lower end portion of the upholstery material 14 is placed on the lower frame 11 while strongly pulling the fixing plate 26 downward. After hanging around the back surface and the bottom surface of the recumbent rod 11a and pulling the fixing plate 26 forward together with the tension member 14 with the recumbent rod 11a as a fulcrum, both ends of the fixing plate 26 are connected to the upper surfaces of the left and right mounting brackets 17 and 17, respectively. Put it on. In this state, as shown in FIG. 5, set screws 28, 28 inserted into through holes 27, 27 provided at the left and right projecting ends of the fixing plate 26 are attached to the inward pieces 17 a of the left and right mounting brackets 17, 17. For installation, it is screwed into the screw hole 29 and tightened.

Thus, the assembly of the backrest 10 is completed, and the upholstery material 14 is stretched on the back frame 13 with a predetermined tension state.
After the backrest 10 is assembled, both the inwardly facing pieces 17a and 17a are drilled in the state in which the left and right mounting brackets 17 and 17 are inserted between the opposing surfaces of the seat body 6 adjacent to the left and right armrests 9 and 9, respectively. The backrest 10 is attached to the seat body 6 by being fixed to the upper surfaces of both sides of the rear end portion of the seat plate 7 by screws (not shown) inserted in the two front and rear mounting holes 30, 30. In addition, after attaching the backrest 10, the cushion material 8 is attached to the upper surface of the seat plate 7 so as to cover the upper surfaces of the left and right inwardly facing pieces 17a and the horizontal ribs 11a.

  As described above, in the backrest of the above embodiment, the bag-like portion 22 on the outer peripheral edge of the upholstery material 14 is inserted into the upper frame 12, and the lower end portion of the upholstery material 14 is connected to the lower frame of the back frame 13. As shown in FIGS. 1 and 5, the front end is fixed to the mounting bracket 17 for mounting the seat plate 7 while pulling forward so as to hang around the rear surface and the lower surface of the ladle 11 a of 11. When pulling the upholstery 14 forward, the left and right corners of the lower end of the back frame 13 can be easily covered with the lower part of the upholstery 14.

Further, the outer side surfaces of the left and right mounting brackets 17 are covered with both armrests 9 and the reeds 11a are covered with the cushioning material 8, respectively, and are not exposed to the outside.
Furthermore, the upper half of the upholstery material 14 that supports the back is a low-density part 23 with fine mesh, and the lower part of the upholstery material 14 that supports the vicinity of the lower back is a finer mesh than the mesh of the upper half of the upholstery material 14. Since the high density portion 24 and the low density portion 23 having the same roughness as the mesh of the upper half mesh portion are alternately formed in the vertical direction, the flexural rigidity of the upper half portion of the upholstery material 14 is It becomes larger than that, and it will bend backward greatly with a small load compared with the lower part.
Accordingly, the amount of bending of the upper half and the lower portion of the upholstery material 14 can be appropriately different from each other. For example, when the lower portion of the upholstery material 14 is set to a small amount of bending so as to have a lumbar support function. However, since the amount of bending of the upper half of the upholstery material 14 can be increased, a comfortable sitting comfort can be obtained.

  In the above embodiment, the bag-like portion 21 at the lower edge of the upholstery material 14 is fixed to the upper surfaces of the left and right mounting brackets 17 by the fixing plate 26. However, the bag-like portion 21 is provided or the fixing plate 26 is Without using, you may fix the lower end part of the upholstery material 14 directly to the lower surface of the rear-end part of the seat board 7 by tacking.

  In the above-described embodiment, the upholstery material 14 is stretched by inserting the downward U-shaped bag-like portion 22 formed on the outer peripheral edge thereof into the upper frame 12. May be formed in a bag shape that is open and covered with the back frame 13 from above. In this way, the upholstery material 14 can be easily stretched from above on the frame-like back frame 13 and can be easily replaced. Also in this case, the lower end portion of the upholstery material 14 may be fixed to the lower surface of the rear end portion of the seat plate 7 by tacking or the like as described above.

  In the above embodiment, the low density portions 23 and the high density portions 24 are alternately formed in the vertical direction so that the amount of bending of the lower portion of the upholstery material 14 can be adjusted. It is good.

It is a perspective view of one embodiment of the backrest of the chair of the present invention. Similarly, it is a front view. Similarly, it is an exploded perspective view of a backrest. Similarly, it shows the assembling procedure of the backrest, and is a perspective view of a state in which the upholstery is temporarily attached to the back frame. Similarly, it is the perspective view after the end of the assembly of the backrest.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Leg 2 Pillar 3 Caster 4 Leg ridge 5 Support base 6 Seat body 7 Seat board 8 Cushion material 9 Armrest 10 Backrest 11 Lower frame 11a Recliner 11b Upward side ridge 12 Upper frame 12a Downward side ridge 13 Back frame 14 Tension material 15 Connecting rod 16 Mounting hole 17 Mounting bracket 17a Inwardly facing piece 18 Mounting hole 19 Set screw 20 Female screw hole 21 Bag-shaped portion 22 Bag-shaped portion 23 Low-density portion 24 High-density portion 25 Opening 26 Fixing plate 27 Through-hole 28 Set screw 29 Female screw hole 30 Mounting hole

Claims (5)

  In a backrest of a chair formed by stretching a woven or woven upholstery material on an upper frame having a U-shape in a front view in the back frame, the back of the occupant above the upholstery material The portion that supports the mesh is a low-density portion with a coarse mesh, and at least a part of the portion that supports the vicinity of the waist in the lower portion is also a high-density portion with a finer mesh than the upper portion of the upholstery material. The backrest of the chair characterized by that.   The left and right side bars in the upper frame are bent in a square shape so that the lower part in the vertical direction protrudes forward, and the upper part of the bent part is a low density part, and the bent part. The chair backrest according to claim 1, wherein at least a part of the lower portion in the vertical direction is a high-density portion.   The backrest of the chair according to claim 1 or 2, wherein the lower portion of the upholstery material is formed by alternately arranging a high density portion and a low density portion in the vertical direction.   The backrest of the chair according to claim 3, wherein the high density portion and the low density portion at the lower part of the upholstery material are formed in a strip shape in the left-right direction. The chair according to any one of claims 1 to 4, wherein the upholstery is formed into a single mesh, and a downward U-shaped bag-like portion provided on the outer periphery thereof is inserted into the upper frame and stretched. Backrest.

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