JP2009112397A - Backrest device of chair - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a backrest device of a chair which is capable of providing comfortableness to sit by increasing the backward flexibility of a stretching material. <P>SOLUTION: In the backrest device of a chair where a bag like stretching material 12 opening downward is stretched across a back frame 11 formed by coupling the upper ends of right and left side frames 14a directing the vertical direction by an upper frame 14b directing the right and left direction, The stretching material on the rear side is swollen rearward by connecting intermediate parts of the side frames 14a in the vertical direction by an intermediate frame 14d having a rearward convex arcuate shape when viewed from the top. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a chair backrest device in which a back frame is covered with a bag-like upholstery material that opens downward.

  The chair backrest device as described above is described in, for example, Patent Document 1 and is well known.

The chair backrest device described in Patent Document 1 is formed in a U-shape facing downward in a front view formed by connecting upper ends of left and right side frames facing in the vertical direction with upper frames facing in the horizontal direction. The entire back frame has a configuration in which a bag-like opening that opens downward and a tension material made of mesh or the like is stretched.
European Patent Application No. 0922419 (FIGS. 3 to 6)

  In the conventional chair backrest device described in Patent Document 1, the front tension material and the rear tension material in the bag-shaped tension material stretched on the back frame are close to each other. For this reason, when the seated person leans back, the front tension material bends backward and comes into contact with the rear tension material, and bends rearward together with the rear tension material.

  If it becomes like this, since the amount of bending to the back of the upholstery material when the seated person leans on the backrest is suppressed, the back is not comfortably supported, and the sitting comfort is deteriorated.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a chair backrest device that can provide a comfortable sitting comfort by increasing the amount of bending of the upholstery material to the rear. .

According to the present invention, the above problem is solved as follows.
(1) The back of a chair formed by stretching a bag-like upholstery that opens downward on the back frame that connects the upper ends of the left and right side frames facing the top and bottom with the upper frame facing the left and right direction. In the twisting device, the intermediate portions in the vertical direction of the both side frames are connected with an intermediate frame having a convex arc shape facing backward in plan view, whereby the rear tension material is bulged rearward.

(2) In the above item (1), the both side frames are bent in a square shape with the lower part protruding forward, and the intermediate parts of the side frames above the bent part are Connect with an intermediate frame.

(3) In the above item (1) or (2), the upper frame is also curved in a convex arc shape backward in plan view.

(4) In any one of the above items (1) to (3), an attachment portion for an optional member that can be attached to the back side of the backrest is provided in the center portion in the left-right direction of the intermediate frame.

According to the first aspect of the present invention, the rear tension member stretched on the back frame is bulged rearward by the intermediate frame that is connected to the left and right side frames and has a convex arc shape facing backward in plan view. Thus, when the front tension member and the rear tension material are separated from each other, and the seated person leans back, only the front tension material is bent backward.
As a result, it is possible to increase the amount of rearward bending of the upholstery material with a small load, which not only provides a comfortable seating comfort, but also makes the backrest feel more voluminous. The appearance of is improved.

  According to the second aspect of the present invention, the front tension member and the rear tension material are largely separated from each other and are separated in a wide area in the vertical direction, so that the entire back is comfortably supported.

According to the invention described in claim 3, the front tension member and the rear tension material are further separated from each other in a wide area from the upper end portion to the lower end portion. Comfortably supported.
In addition, since the entire backrest becomes voluminous, the appearance of the backrest is improved.

  According to the fourth aspect of the present invention, the optional member can be attached to the back side of the backrest using the intermediate frame.

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

  1 and 2, a chair 1 includes a leg body 4 including five leg rods 3 facing in a radial direction and having a caster 2 attached to a tip thereof, and a gas spring which is erected at the center and accommodated in the center. (Not shown) can be expanded and contracted, a supporting base 6 fixed to the upper end of the supporting pillar 5, a seat 7 attached to the upper part of the supporting base 6, and both ends of the supporting base 6 Against the urging force of the gas spring 9 attached between the rear end of the support base 6 and the rear part of the dorsal fin 8, which is attached to the upper part of the dorsal fin 8 with the front end pivotally attached and the back support 8. And a backrest 10 that can be tilted backward.

  The backrest 10 includes a back frame 11 and a bag-like upholstery material 12 that covers the entire surface except the lower end thereof and is open at the bottom.

  As shown in FIGS. 3 and 4, the pair of left and right dorsal fins 8, 8 that are spaced in parallel to each other face the front below the rear part of the seat body 7, and the front end side is pivotally attached to the support base 6, and the rear end side The seat 7 has a standing portion 8a that stands up in the rear upper direction, and is formed in an L-shape that is substantially forward-facing in a side view. The opposing surfaces of both standing parts 8a are connected by a connecting plate 13.

  The back frame 11 includes a back frame main body 14 formed of a hard synthetic resin material, and a pair of left and right protective members 15 formed of a material softer than the back frame main body 14 such as rubber, elastomer, soft plastic, etc. 15.

  The back frame main body 14 is composed of left and right side frames 14a and 14a facing in the up and down direction, an upper frame 14b facing in the left and right direction connecting the upper ends of both side frames 14a, and left and right side frames 14a and 14a. The lower frame 14c that is provided at the lower end and faces in the left-right direction is integrally formed in a substantially rectangular frame shape in a front view in which the lower portion is slightly narrow. Between the upper frame 14b and the lower frame 14c, an intermediate frame 14d that connects the vertical intermediate portions of the left and right side frames 14a and 14a and that faces the left and right is integrated with the side frames 14a and 14a. Is formed.

  The left and right side frames 14a and 14a are arranged such that an intermediate portion 16 (hereinafter referred to as a bent portion 16) near the lumbar portion of the seated person, that is, slightly below the central portion in the vertical direction protrudes forward in a side view. It is bent in a nearly square shape. The upper frame 14b and the lower frame 14c are gently curved in a backward convex arc shape.

As shown in FIGS. 3 and 4, the intermediate frame 14d is separated from the bent portions 16 of the left and right side frames 14a, 14a largely upwards, and is connected to a position relatively close to the upper frame 14b. Are formed in a plate shape having a predetermined width.
Further, as shown in the cross-sectional plan view of FIG. 5 (the attached parts attached to the intermediate frame 14d are not shown), the middle portion in the left-right direction protrudes more backward than the left and right side frames 14a. Further, when the bag-like tension member 12 is put on the back frame 11 as will be described later, the front tension member 12a and the rear tension member 12 of the tension member 12 are curved. A large space is formed between the surfaces facing 12b.

A plurality of attachment holes 17 penetrating in the front-rear direction are provided in the center portion in the left-right direction of the intermediate frame 14d so that an optional member can be attached.
The optional member is, for example, a name plate or a hanger. In this embodiment, a name plate 18 is attached. That is, the nameplate 18 is inserted into the mounting hole 19 provided in the plate 18 and the mounting hole 17 of the intermediate frame 14d, and is inserted into the screw hole (not shown) of the mounting plate 20 disposed on the front side of the intermediate frame 14d. Are attached to the rear surface of the intermediate frame 14d.

  As shown in FIG. 3, a rearwardly and downwardly recessed U-shaped recess 22 is formed in the lower center of the rear surface of the lower frame 14c. The upright portion 8a of the dorsal fin 8 is inserted through openings 25 and 26 provided in the center of the bottom plate 23 fixed to the bottom surface of the lower frame 14c with screws (not shown) and the backrest lower cover 24, respectively. 8a and the connecting plate 13 are inserted.

  The upright portions 8a and 8a and the connecting plate 13 inserted into the recess 22 are fixed to the rear surface of the lower frame 14c by screws (not shown) with the upright portions 8a and 8a and the connecting plate 13 interposed therebetween. It is fixed by. Thereby, the back frame 11 is fixed to the backpack 8. Note that after the attachment plate 28 is attached, the rear opening of the recess 22 is closed by the backrest rear cover 28.

  As shown in FIG. 3 to FIG. 5, on the outer surface from the connecting corner of the upper frame 14 b and the left and right side frames 14 a and 14 a in the back frame body 14 to the vicinity of the bent portion 16 of the side frame 14 a. The notch grooves 29 and 29 are formed in the vertical direction. On the outer side surfaces of both the notch grooves 29 and 29, the ridges 30 whose front side slightly protrudes outward are integrated in the longitudinal direction. Is formed.

  The left and right protective members 15, 15 are fitted in the cutout concave groove 29 to have a vertical dimension that can cover the same, and the front-rear dimension is substantially the same as the front-rear dimension of the outer portion of the side frame 14 a. A concave groove 31 is formed on the inner surface in the longitudinal direction.

  As shown in FIGS. 5 and 6, the ridges 30 of the side frame 14 b and the concave grooves 31 of the protective material 15 have shapes complementary to each other so that they are closely fitted. . It should be noted that the amount of recess of the notch groove 29 provided in the portion of the back frame main body 14 where the protection material 15 is attached is substantially equal to the thickness of the protection material 15, and when the protection material 15 is fitted into the notch recess groove 29. The back frame main body 14 and the outer surface of the protective material 15 are aligned with each other.

  The groove 30 formed in the left and right protective members 15 and 15 is fitted to the ridges 30 formed on the both side frames 14a and 14a of the back frame main body 14 while elastically deforming the protective member 15 in an outward opening shape. By doing so, both the protective members 15 are attached to both side surfaces of the back frame main body 14.

  The upholstery material 12 is made of a woven or woven synthetic fiber having high tension and elasticity, such as polyamide fiber or polypropylene fiber, and is formed in a bag shape having an open bottom. The dimensions of the upholstery material 12 are determined in advance so that an appropriate tension is applied to the upholstery material 12 when the upholstery material 12 is put on the back frame 11.

  The portion of the upholstery 12 that supports the back of the occupant, that is, the portion above the bent portion 16 of the side frame 14a, is a low-density portion 32 having a coarse mesh so as to have air permeability and translucency. In addition, the portion below the bent portion 16 that supports the vicinity of the waist of the seated person is a high-density portion with a finer mesh than the upper portion so that the attachment portion of the dorsal fin 8 in the lower frame 14c is less visible from the outside. 33.

  The tension member 12 is placed on the back frame 11 from above, and then the lower end portion is fixed to the lower surface of the bottom plate 23 attached to the lower end of the back frame main body 14 by tacking or the like and sandwiched by the backrest lower cover 24 The back frame 11 is stretched in a predetermined tension state.

As described above, when the low density portion 32 and the high density portion 33 are provided on the upper portion of the tension member 12 and the lower portion thereof, the upper tension of the front tension member 12a becomes smaller than the lower tension, and the front tension member 12a. The amount of deflection of the upper part of the rear is greater than the amount of deflection of the lower part.
As a result, the upper portion of the front tension member 12a that supports the back of the seated person can be easily bent rearward, and the amount of bending of the lower portion of the front tension member 12a that supports the vicinity of the waist is reduced, thereby providing a lumbar support function. As a result, a comfortable sitting comfort can be obtained.

As described above, in the above-described embodiment, the upper frame 14b, the lower frame 14c, and the intermediate frame 14d are each gently curved in a convex arc shape in the rearward direction. And a large space is formed between the surfaces facing the front tension member 12a.
As a result, the amount of rearward bending of the front tension member 12a can be increased, and not only a comfortable sitting comfort can be obtained, but also the backrest 10 can have a sense of volume, and the appearance is good. .

  Moreover, since an optional member can be attached to the back side of the backrest using the intermediate frame 14d, the practicality is also improved.

It is a front view of a chair provided with one embodiment of the present invention. Similarly, it is a side view of a chair. Similarly, it is an exploded perspective view of a backrest. Similarly, it is a center longitudinal cross-section enlarged side view of the backrest. FIG. 5 is an enlarged cross-sectional plan view of an essential part of the VV line of FIG. 4. FIG. 6 is an enlarged view of a VI part in FIG. 5.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Chair 2 Caster 3 Leg rod 4 Leg body 5 Pillar 6 Support base 7 Seat body 8 Backrest 8a Standing part 9 Gas spring 10 Backrest 11 Back frame 12 Tension material 12a Front tension material 12b Rear tension material 13 Connection Plate 14 Back frame body 14a Side frame 14b Upper frame 14c Lower frame 14d Intermediate frame 15 Protective material 16 Intermediate part (bent part)
17 Mounting hole 18 Name plate 19 Mounting hole 20 Mounting plate 21 Mounting screw 22 Recess 23 Bottom plate 24 Backrest lower cover 25 Opening 26 Opening 27 Mounting plate 28 Backrest rear cover 29 Notch recess 30 Convex line 31 Concave groove 32 Low density part 33 High density part

Claims (4)

In a backrest device for a chair, in which a bag-like upholstery that opens downward is stretched on a back frame formed by connecting upper ends of left and right side frames facing up and down with an upper frame facing in the left and right direction ,
The backrest of the chair, characterized in that a back tension member is bulged rearward by connecting the intermediate portions in the vertical direction of the both side frames with an intermediate frame having a convex arc shape facing rearward in plan view. apparatus.   The both side frames are bent in a side-view shape with the lower portion protruding forward, and the intermediate portions of the side frames above the bent portion are connected by an intermediate frame. Chair backrest device as described.   The backrest device for a chair according to claim 1 or 2, wherein the upper frame is also curved in a convex arcuate backward in plan view.   The backrest device for a chair according to any one of claims 1 to 3, wherein an attachment portion for an optional member that can be attached to the back side of the backrest is provided at a central portion in the left-right direction of the intermediate frame.

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