JP5452904B2 - Chair - Google Patents

Description

  The present invention relates to a chair, and more particularly to a support structure for the backrest thereof.

  In a conventional chair, a seated person leans against the backrest by supporting both sides of the rear surface of the middle part in the vertical direction of the backrest with a ball joint on the upper end of a pair of left and right backrest support rods. In some cases, the supporting point of the backrest can be freely tilted in all directions to improve sitting comfort without causing unreasonableness (see, for example, Patent Document 1).

Also, in recent years, while taking a comfortable posture with the back tilted, the eyes and arms can be pointed forward or forward and downward, so that the keyboard can be driven in an easy posture. In some cases, when the support heel is tilted backward, the backrest is bent so as to protrude backward in a side view (see, for example, Patent Documents 2 and 3).
Japanese Utility Model Publication No. 39-2881 Japanese Patent No. 4070407 Japanese Patent No. 4060913

In what is described in Patent Document 1, since a ball joint is used, a high degree of processing accuracy is required, and the manufacturing cost of the entire chair increases.
Moreover, in what is described in Patent Documents 2 and 3, the backrest itself must have a structure that can be bent at an intermediate portion, and the support structure for the backrest is complicated. .

  In view of the above-mentioned problems of the prior art, the present invention supports the backrest with a simple structure, without excessive force, and with good sitting comfort without using expensive means such as a ball joint. The aim is to provide a chair that can be used.

According to the present invention, the above problem is solved as follows.
(1) In the support structure of the backrest in the chair supporting the both sides of the back surface of the backrest that can be elastically deformed on both sides of the upper end of the backrest support rod standing up from the rear of the seat, The front end portion of the convex shaft projecting on either one of the back side of the backrest facing it is fitted into the receiving hole provided on the other side, and substantially provided on the front end portion of the convex shaft A shaft pin facing in the left-right direction, a retaining pin facing substantially in the left-right direction in which both ends are fixed to the member provided with the receiving hole, the backrest being rotatable about the axis line in which the back-right direction is directed, and It also fits freely in a direction deviating from the axis so that the required angle can be rotated.

With such a configuration, the backrest is not only around the axis line in the left-right direction but also from the above-mentioned axis line by a simple structure in which a retaining pin is loosely fitted in the shaft hole provided at the tip of the convex shaft. Since it can be supported in such a direction as to be able to rotate at a required angle, it is possible to support the backrest comfortably and comfortably without using an expensive means such as a ball joint.

  (2) In the above item (1), the shaft hole has a tapered hole shape in which the inner diameter of the central portion is substantially equal to the outer diameter of the retaining pin and gradually increases from the central portion toward both sides.

  With such a configuration, the retaining pin does not rattle in the shaft hole, and the retaining pin can be smoothly inclined at a required angle in all directions with respect to the central axis of the shaft hole. .

  (3) In the above item (1) or (2), the tip of the convex shaft is a sphere, and the shaft hole passes through the center of the sphere.

  With such a configuration, the tip end portion of the convex shaft can smoothly rotate in all directions within the receiving hole.

  (4) In any one of the above items (1) to (3), the lower portion of the backrest supporting heel is configured with a pair of left and right forward ridges that extend in a bifurcated manner on both sides toward the front. The front end of the heel is pivotally attached to the support base supported by the legs and supporting the seat with a pivot that faces in the left-right direction, and the backrest is always urged forward toward the front. In addition, a portion of the support base that is rearward of the pivot and a lower portion of the backrest that is above the pivot are connected by a connecting rod.

With such a configuration, when the backrest support heel tilts backward during reclining, the connecting heel also tilts backward along with it, and due to the difference in the rotation center between the backrest support heel and the connection heel, The lower part of the saddle is pushed backward by the rear end of the connecting saddle, and the backrest is rotated with respect to the backrest support saddle in the direction of rotation of the backrest support saddle about the axis that faces in the left-right direction. ) And the opposite direction (standing direction).
That is, during reclining, even if the backrest support heel tilts backward, the backrest is restrained from tilting backward and tries to keep standing, so the seated person takes an easy posture with the back tilted backward. On the other hand, it is possible to point the eyes and arms forward or forward and downward effortlessly, and to perform a keyboard driving operation and the like with an easy posture.

  According to the present invention, it is possible to provide a chair that can support the backrest with a simple structure, without causing unreasonableness, and without having to use expensive means such as a ball joint.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
1-6 shows the chair which is one Embodiment of this invention.

  As shown in FIGS. 1 and 2, the chair includes a leg body 3 having five leg rods 2 having a radial shape with a caster 1 provided at the tip. In the center of the leg 3, a telescopic leg column 4 having a gas spring (not shown) is erected, and the rear part of the support base 5 is fixed to the upper end of the leg column 4.

  The support base 5 has a substantially hollow box shape with an upper surface opened, and the opening on the upper surface is covered with a removable cover (not shown).

  Inside the support base 5, there are a biasing means for biasing the backrest 6, that is, biasing forward, a biasing means for biasing the seat 7 forward (all not shown), and the like. Although they are provided, they are not directly related to the present invention, and thus illustration and detailed description thereof are omitted.

A hexagonal column-shaped pivot 8 that faces in the left-right direction is pivotally supported at the rear portion of the support base 5 so as to be rotatable about its central axis.
At both ends of the pivot 8 protruding left and right from both side walls of the support base 5, the front end portions of the backrest support rod 9 that supports the backrest 6 are fixed so as to rotate integrally with the pivot 8. Yes. The pivot 8 is provided in the support base 5 by an urging means (not shown) made of a torsion coil spring or the like, for example, in a direction in which the backrest 6 and the backrest support rod 9 stand, that is, counterclockwise in FIG. Is being energized.

  The backrest support 9 has a substantially L-shaped side view in which an upright portion 9a facing upward and a forward facing portion 9b facing forward are connected to each other via a bent portion 9c. The raised portion 9a is bent It consists of a pair of left and right standing ridges 9d, 9d extending in a bifurcated manner from the portion 9c, and the forward facing portion 9b is a pair of left and right extending in a bifurcated manner from the bent portion 9c. Each of the ends of the pivot 8 is fixedly fitted in hexagonal holes 9f, 9f facing left and right provided at the front ends of the pair of left and right forward saddles 9e, 9e. .

  As shown in FIGS. 3 and 4, the left and right standing rods 9d, 9d of the backrest supporting rod 9 are extended in an arc shape obliquely upward and outward from the bent portion 9c, and the left and right forward rods 9e, 9e is extended obliquely outwardly forward and downward, so that the backrest supporting rod 9 has an X-shape when viewed from the rear, and the lateral width of the bent portion 9c, which is the intersection at the center thereof, It is larger than the width of 9e and swells in a substantially spherical shape toward the rear.

A continuous shallow recess 10 is formed on the rear surface of the bent support 9c and the upright rods 9d and 9d in the backrest support rod 9 and the rear surface of the forward facing rods 9e and 9e to the rear portion of the lower surface. A protective cover 11 that is provided and covers the back surface of the backrest support rod 9 is detachably fitted to the recess 10 and is adhered to the backrest support rod 9 with an adhesive or a hook-and-loop fastener, or as required. Screwed.
The thickness of the protective cover 11 is preferably substantially equal to the depth of the recess 10 so that the surface of the protective cover 11 and the surface of the backrest support rod 9 are aligned so that no step is generated.

  The protective cover 11 is made of a soft synthetic resin material, rubber, or other cushioning material. The protective cover 11 is provided with a bent cover portion 11a that covers the rear surface of the bent portion 9c of the backrest support rod 9, and is connected to the bent cover portion 11a. A standing cover portion 11b that covers the rear surface of the standing rod 9d and a forward cover portion 11c that is connected to the bent cover portion 11a and covers the lower surface of each forward rod 9e.

  A concave portion 12 for attaching the backrest 6 is provided on the rear surface of the upper end portion of each standing rod 9 d in the backrest supporting rod 9, and the front surface of the upper end portion of each standing covering portion 11 b in the protective cover 11 is provided in the concave portion 12. By press-fitting the elastic projection 11d provided on the back cover 6, the front end portion of each upright covering portion 11b in the protective cover 11 can be securely attached to the backrest support rod 9 so that it is difficult to peel off, and the backrest 6 The mounting recess 12 is closed so that the appearance can be improved.

  Further, a gap (not shown) is formed in a part of the facing portion between the back surface of the back support rod 9 and the front surface of the protective cover 11, and at least a portion corresponding to the gap in the protective cover 11 is made of an elastic material. When the other object comes into contact with the rear surface of the portion of the protective cover 11 corresponding to the gap portion, the portion is elastically deformed so that the portion enters the gap portion, thereby buffering the protective cover 11. Can be further enhanced.

  Since such a protective cover 11 is provided on the backrest support rod 9, when the chair is turned, the backrest support rod 9 abuts against another object and damages it, or the backrest support rod 9 itself In particular, the lower surface of the forward-facing portion 9b of the backrest support rod 9 abuts against the upper surface corner of the lower floor object, and damages it. It is possible to prevent the backrest support ridge 9 itself from being damaged.

  The backrest 6 is a plate material made of an elastically deformable soft synthetic resin material having an arc shape whose center is recessed rearward in plan view, or a cushion material (not shown) sandwiched between the front surface material and a skin material (Not shown) and the like, and the rear surfaces of both side portions in the middle portion in the up-and-down direction are around the axis line facing the left and right upright portions 9d and 9d of the backrest supporting rod 9 and substantially in the left-right direction. And can be rotated at a required angle in a direction away from the axis.

  In order to support the backrest 6 in this way, as shown in FIG. 5, the front end portion of the convex shaft 13 protruding from the front surface of the upper end portion of each upright saddle 9 d in the backrest support rod 9 is used as the backrest 6 opposite to it. It is fixed to the rear surface of the backrest 6 so as to form the receiving hole 14 in the shaft hole 15 that is fitted in the receiving hole 14 provided on the rear surface of the side portion and that faces the substantially right and left direction provided in the tip portion of the convex shaft 13. A retaining pin 17 having both ends fixed to each other is fixedly fitted to a cylindrical portion 16a that opens rearward in the receiving plate 16 and faces substantially in the left-right direction.

  The tip 13a of the convex shaft 13 is a sphere, and the shaft hole 15 passes through the center of the sphere. The shaft hole 15 has an inner diameter of the central portion 15a substantially equal to the outer diameter of the retaining pin 17. In addition, tapered hole portions 15b and 15b that gradually increase in diameter toward the outside are formed on both sides from the central portion 15a.

  In the example shown in FIG. 5, the retaining pin 17 is a bolt, which passes through the cylindrical portion 16 a in the receiving plate 16 and the shaft hole 15 in the distal end portion 13 a of the convex shaft 13, and has a nut at the distal end portion. By screwing 17a, the retaining pin 17 is retained from the cylindrical portion 16a and the shaft hole 15, and the convex shaft 13 is retained from the receiving hole 14, respectively. The retaining pin 17 may be a mere pin that is not a bolt, and the orientation of the retaining pin 17 may be parallel to the orientation of the rear surface of the backrest that is slightly inclined with respect to the lateral direction as well as the lateral direction. . Furthermore, the outer periphery of the connecting portion between the convex shaft 13 and the cylindrical portion 16a is covered with an elastically deformable cover 18.

  An enlarged diameter flange portion 13b is formed at the intermediate portion of the convex shaft 13, and the enlarged diameter flange portion 13b is in contact with the front surface of the upper end portion of the standing rod 9d so that the proximal end portion 13c of the convex shaft 13 is formed. Are fitted into the rearward shaft hole 19 provided on the front surface of the upper end of the standing rod 9d, and the convex shaft 13 is fitted by the fixing screw 20 fitted to the concave portion 12 provided on the rear surface of the upper end portion of the standing rod 9d. By sticking to the standing rod 9d, the convex shaft 13 is firmly fixed to the upper end portion of the standing rod 9d.

The rear end surface of the receiving hole 14 is preferably a spherical surface that is complementary to the spherical surface of the tip end portion 13 a of the convex shaft 13.
The convex shaft 13 is provided on the rear side surface of the backrest 6 so as to protrude rearward, and a receiving hole 14 is formed on the front surface of the upper end portion of each upright saddle 9d in the backrest support rod 9 facing the convex shaft 13. Also good.

  When the backrest 6 is supported in this way, the backrest 6 faces in the left-right direction with a simple structure in which the retaining pin 17 is loosely fitted in the shaft hole 15 provided at the tip of the convex shaft 13. Since it can be supported not only around the axis but also in a direction deviating from the above-mentioned axis so that the required angle can be rotated, without using an expensive means such as a ball joint, the backrest 6 can be produced without any unreasonableness. It can be supported comfortably.

  The portion of the support base 5 behind the pivot 8 and the lower portion of the backrest 6 above it are connected by a connecting rod 21, and when the backrest supporting rod 9 is tilted backward, the lower portion of the backrest 6 is The backrest support rod 9 is pushed backward by a connecting rod 21 that is rotated rearward and downward.

  That is, the front end portion of the connecting rod 21 is connected to the support base 5 with the shaft 22 facing in the left-right direction, and the rear end portion of the connecting rod 21 is the back of the mounting bracket 23 fixed to the rear surface of the lower end portion of the backrest 6. A shaft 24 that faces in the left-right direction is connected to a lower end portion that projects downward from the flange 6.

  The connecting rod 21 is a rigid body having a circular arc shape when viewed from the side with the center of curvature located above (or below) the connecting rod 21, and is disposed between the pair of left and right forward facing rods 9e, 9e in the backrest supporting rod 9. In this way, it is sandwiched between both forward-facing rods 9e, 9e and is not easily exposed to the outside.

  With such a configuration, as shown in FIG. 6, when the backrest support rod 9 tilts backward during reclining, the connecting rod 21 also tilts backward along with it, and the backrest support rod 9 rotates at that time. Due to the difference between the center (pivot 8) and the rotation center (axis 22) of the connecting rod 21, the lower part of the backrest 6 is pushed backward by the rear end of the connecting rod 21, and the backrest 6 is backrest. With respect to the support rod 9, the backrest support rod 9 is rotated in the opposite direction (stand-up direction) to the rotation direction (backward tilt direction) about the axis line (the retaining pin 17) facing in the left-right direction.

  The rear and front portions of the seat support 25 for supporting the seat 7 so as to be adjustable in the front-rear position are rear support means 26 for guiding the backrest support rod 9 to move rearward and downward in conjunction with the rearward tilt of the backrest support rod 9. It is supported by the support base 5 with the front support means 27.

The rear support means 26 includes a link 29 having a lower end pivotally attached to a portion of the support base 5 behind the pivot shaft 8 of the backrest support rod 9 and ahead of the shaft 22 of the connecting rod 21 with a shaft 28 in the left-right direction. The upper end portion is pivotally attached to the rear portion of the seat support body 25 with a shaft 30 in the left-right direction, and the shaft 30 at the upper end portion of the link 29 is connected to the lower end portion of the link 29 in each forward-facing rod 9e. It is assumed that it is slidably fitted in a long hole 31 provided in the rear part of the shaft 28 and directed substantially in the front-rear direction.
The long hole 31 is provided in an upward projecting piece 9g provided in a part slightly rearward of the hexagonal hole 9f in each forward flange 9e of the back support rod 9.

The front support means 27 is configured such that a left and right shaft 32 provided at the front portion of the seat support 25 is slidably fitted into a long hole 33 provided on the support base 5 and directed downward.
The shaft 32 is constantly urged forward by an urging means (not shown) provided in the support base 5.

  The front support means 27, instead of the above configuration, connects the upper end portion of the upward support link provided at the front portion of the support base to the front portion of the seat, as described in Patent Document 1. Thus, the support link may be tilted backward (not shown).

  Since this chair is configured as described above, when the seated person leans on the backrest 6, the backrest 6 is elastically deformed so that the center part is recessed backward from the both side parts in plan view. . The elastic deformation of the backrest 6 at this time is allowed by slightly tilting the left and right retaining pins 17 in the shaft hole 15 of the convex shaft 13.

Along with the backrest 6, the backrest support collar 9 is tilted backward against the urging force of the urging means provided in the support base 5. It is tilted backward about 22.
At this time, the rearward tilting speed of the connecting rod 21 is larger than the rearward tilting speed of the backrest supporting rod 9, and the shaft 22 of the connecting supporter 21 is located behind the pivot 8 of the backrest supporting rod 9. Thus, the lower end portion of the backrest 6 is pushed backward by the shaft 24 at the rear end portion of the connecting rod 21, and the backrest 6 is directed to the backrest supporting rod 9 in the left-right direction (retaining pin). 17), the backrest supporting rod 9 is rotated in the direction opposite to the direction of tilting (backward tilting direction) (standing direction).

  That is, when reclining, even if the backrest support rod 9 is tilted backward, the backrest 6 is restrained from tilting backward and tries to maintain a standing position. The user can easily point his / her eyes and arms forward or forward / downward while taking care of the keyboard, so that the keyboard can be driven in an easy posture.

  Furthermore, a keyboard having a comfortable posture as described above can be obtained simply by adding a simple structure in which the support base 5 and the lower part of the backrest 6 are connected to the basic structure of the conventional chair by the connecting rod 21. The backrest 6 itself can be bent in the front-rear direction as viewed from the side, and there is no need to support the backrest 6 with a complicated support structure. The structure of the whole chair can be simplified.

As the backrest support rod 9 is tilted backward, the long hole 31 provided in the upward projecting piece 9g moves the shaft 30 rearward and downward, thereby tilting the link 29 backward.
At this time, the backward tilting angular velocity of the link 29 is larger than the backward tilting angular velocity of the backrest support rod 9, and the shaft 28 of the link 29 is located behind the pivot 8 of the backrest support rod 9. The rearward movement amount of 30 is larger than the rearward movement amount of the long hole 31 in the back support rod 9, and the shaft 30 is slid rearward in the long hole 31, and the movement of the shaft 30 at that time Thus, the rear portion of the seat support 25 is greatly moved rearward and downward.

  That is, it is possible to increase the rearward movement stroke of the rear portion of the seat 7 when the backrest support rod 9 is tilted backward, thereby connecting the lower portion of the backrest 6 when the backrest support rod 9 is tilted backward. The rear part of the seat 7 can be moved rearward largely following the rear end being pushed by the rear end part of the collar 21, and the lower end of the backrest 6 and the rear part of the seat 7 are prevented from separating. Thus, a comfortable seating feeling can be obtained.

  As the rear portion of the seat support body 25 is moved rearward and downward by the shaft 30, the front portion of the seat support body 25 resists the biasing force of the biasing means provided in the support base 5, When the front shaft 32 slides rearward and downward along the long hole 33, the front shaft 32 is smoothly moved rearward and downward.

  As described above, when the backrest support rod 9 is tilted backward, the backrest 6 is pivoted with respect to the backrest support rod 9 so that the lower end portion thereof is pushed rearward by the connecting rod 21 and keeps standing. The seat 6 can move greatly rearward and downward so as to follow the movement of the lower part of the backrest 6, and the eyes and arms can be moved forward or forward and downward while tilting the back to the seated person. It is possible to make it possible to take an easy work posture in which the keyboard can be driven in an easy posture.

  The present invention is not limited to the above-described embodiment, and can be implemented in various modified forms.

It is a front view of the chair which is one embodiment of the present invention. Similarly, it is a side view. Similarly, it is a rear view. FIG. 4 is an enlarged longitudinal end view taken along line IV-IV in FIG. 3. FIG. 5 is an enlarged cross-sectional plan view taken along line VV in FIG. 2. It is a side view when a backrest supporting heel is tilted backward.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Caster 2 Leg rod 3 Leg 4 Leg column 5 Support base 6 Backrest 7 Seat 8 Axis 9 Backrest support rod 9a Standing portion 9b Forward portion 9c Bending portion 9d Standing rod 9e Forward rod 9f Hexagonal hole 9g Upward projection Piece 10 Recess 11 Protective cover 11a Bent cover 11b Standing cover 11c Front cover 11d Elastic protrusion 12 Recess 13 Convex shaft 13a Tip 13b Expanded flange 13c Base end 14 Receiving hole 15 Shaft hole 15a Central portion 15b Tapered hole portion 16 Receiving plate 16a Tube portion 17 Retaining pin 17a Nut 18 Cover 19 Shaft hole 20 Fixing screw 21 Connecting rod 22 Shaft 23 Mounting bracket 24 Shaft 25 Seat support body 26 Rear support means 27 Front support means 28 Shaft 29 Link 30 shaft 31 long hole 32 shaft 33 long hole

Claims (4)

In a chair that supports both sides of the back surface of the backrest that can be elastically deformed on both sides of the upper end of the backrest support rod that stands up from the back of the seat,
A front end portion of a convex shaft projecting on either one of the front surface of the upper end of the backrest supporting rod and the rear side surface of the backrest facing it is fitted into a receiving hole provided on either one of the above, and An axial hole provided at the tip of the convex shaft that faces substantially in the left-right direction is provided with a retaining pin that faces substantially in the left-right direction with both ends fixed to the member provided with the receiving hole, and the backrest faces in the left-right direction. A chair which is freely fitted so as to be rotatable about an axis and capable of rotating at a required angle in a direction away from the axis.   The chair according to claim 1, wherein the shaft hole has a tapered hole shape in which the inner diameter of the central portion is substantially equal to the outer diameter of the retaining pin and gradually increases from the central portion toward both sides.   The chair according to claim 1 or 2, wherein the tip of the convex shaft is a sphere, and the shaft hole passes through the center of the sphere.   The lower part of the backrest supporting heel is composed of a pair of left and right forward heels that extend in a bifurcated manner on both sides toward the front, and the front ends of both forward ridges are supported by legs and support the seat. And pivotally mounted with a pivot that faces in the left-right direction, and the backrest support rod is always urged toward the front, and further, a portion of the support base behind the pivot, and The chair in any one of Claims 1-3 which connected the lower part of the said backrest in the upper direction with the connection rod.

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