JPH09322838A - Chair - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decrease fatigue of a user even when this chair is used at a working posture for a long time and to keep the posture of lumber vertebrae for supporting the wt. of the user at his sitting posture at a reasonable posture being close to natural state by not only making it comfortable to sit at a relaxed posture but also improving feeling to sit especially at a posture in office work. SOLUTION: In a chair provided with a back rest and a seat plate and formed in such a way that the seat plate goes down at back side, a seat shell 20 forming the seat plate is divided into two and the back half side 22 of the divided seat shell 20 is formed into a size in such a way that the pelvis of a sitting person can be easily placed when the person sits down on the seat plate at ordinary office work posture and the back half side 22 of the seat shell 20 is formed in such a way that it can be rocked up and down around the divided point within a range of approximately from 15 to 5 degree to the horizontal face.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chair which is improved in sitting comfort by a conventional product both at the time of working and at the time of relaxing, and more particularly to a chair suitable for office work.

[0002]

2. Description of the Related Art Conventionally, various chairs suitable for office work for improving the sitting comfort have been proposed and many have been put to practical use. A so-called synchro tilt mechanism has been adopted in many office chair structures in recent years, in which the depression of the seat plate and the back tilt of the backrest are interlocked in a fixed relationship.

In the synchro tilt mechanism, when a seat is depressed by a person to hang it, the backrest also tilts backward, interlocking with it, and a person sitting on a chair leans his body on the backrest and tilts the backrest backward. In addition, the interlocking mechanism of the seat plate sinking and the backrest rearward tilt is incorporated so that the seatboard also sinks, and the ratio of the seatboard sinking and the backrest rearward tilt is realized to be, for example, approximately 1: 2. There are many things I did.

In the chair having the synchro tilt function described above, compared to the conventional non-synchro tilt mechanism type chair, in the relaxed or comfortable position with the body rested on the backrest, the clothes on the lower side of the backrest are less likely to be rolled up. Is less likely to occur, but there are few improvements in the office work posture compared to conventional products.

However, in view of the fact that the office chair is usually used in an office work position for a longer time than in a relaxed and comfortable position, the office chair is used for office work. Improving the sitting comfort in the posture is considered to be the primary reason.

[0006]

SUMMARY OF THE INVENTION In view of the above points, it is needless to say that the present invention provides good sitting comfort in a relaxed posture, but particularly improves the sitting comfort in an office work posture. The present invention provides a chair that can reduce fatigue of the user even when used for a long time in a working posture, and can maintain the posture of the lumbar spine that supports the weight of the user in a sitting posture in a comfortable posture close to a natural body. That is the task.

[0007]

The first structure of the chair of the present invention made to solve the above problems is provided with a backrest and a seat plate, and the seat plate is formed so as to sink on the rear side. In the chair described above, the seat shell forming the seat board is divided into two parts in the front and rear, and the rear half of the divided seat shell is seated on the seat board in a normal office work posture.
The seated person's pelvis is formed to have a size that can be comfortably placed, and the rear half of the seat shell can swing up and down about the dividing point within a range of about 15 degrees to -5 degrees with respect to the horizontal plane. It is characterized by being formed as described above.

A second structure of the chair according to the present invention which can solve the above-mentioned problems is to provide a seat shell of a chair, which is divided into front and rear parts and hinged so as to be bendable at the divided parts, and legs are provided at the lower part. In a chair supported by a supporting base provided on the upper part of an upright supporting column so as to project to the front side of the seat shell, the supporting base is provided in the vicinity of the front end portion on the front half side of the divided seat shell. Of the seat shell is supported at its front end through a connecting link member erected so as to be capable of swinging back and forth, and the rear half of the seat shell is swingable back and forth at an intermediate portion of the support base via a shaft. Means for supporting the rear end of a supporting arm of a required length pivotally attached to the connecting link member or the pivot shaft of the supporting arm to constantly urge the link member forward. By connecting and providing, the front half side of the seat shell is substantially horizontal or The rear half of the seat shell is arranged in a slightly smaller front descent posture in a small angle rearward / downward posture, and the rear half side of the seat shell and the lower end side of the backrest member are fixed at a required angle. To do.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of a chair according to the present invention will be described with reference to the drawings. 1 is a side sectional view showing an example of the mechanism of the chair of the present invention, FIG. 2 is a plan view of the mechanism of FIG. 1, FIG. 3 is a front view of the mechanism of FIG. 1, and FIG. 4 shows an operation example of the mechanism of FIG. FIG. 5 is a side sectional view of a seat and a backrest portion of the chair of the present invention, FIG. 6 is a plan view of a seat shell, FIG. 7 is a view of the seat shell of FIG. 9 is a perspective view of an example of the chair of the present invention, and FIGS. 10 and 11 are side views of the chair of the present invention in use.

In FIGS. 1 to 4, 1 is a column similar to a known office swivel chair, which is provided with a leg 1a having a radial caster-1b at a lower portion thereof, and an operating mechanism of a chair described later at an upper end thereof. A box-shaped support base 2 for accommodating the above is rotatably provided in a horizontal plane. The column 1 has a structure in which the height is freely adjustable, such as a type in which a gas spring is installed or a type in which the gas spring is not installed.

In this example, the support base 2 has an outer shape of a substantially oblong rectangular shape when viewed from a plane, and is formed into a substantially anvil-shaped box when viewed from the side, and the box-shaped base is formed. 2 rear lower surface
At 2a, it is mounted on the upper end of the column 1 so as to be freely rotatable. In the box body which becomes the support base 2, a horizontal shaft 3 is provided near the front end 2b thereof, and a horizontal shaft 4 is provided in the vicinity of the mounting portion to the column 1 and slightly forward thereof. Are provided in a direction orthogonal to the length direction of the.

Reference numeral 5 denotes a lower end portion on the shaft 3 in front of the base 2.
A connecting link member in which the upper end side 5b is swingably provided in the front-rear direction of the support base 2 by pivotally attaching 5a, and the lower surface of the seat shell 20, which will be described later, near the front end is the upper end of the link member 5. Connected to side 5b. In the illustrated example, the shaft 3 is in a space relationship, and is attached to the left and right side walls of the box body.
Although it is formed by two short shafts, it may be a through shaft.

The lower ends 5a of the connecting link members 5 are pivotally attached to the two short shafts 3 in the illustrated example, respectively.
At the upper ends 5b and 5b of the link members 5 and 5, the two members 5 and
A shaft 6 passing through 5 is provided. In the example shown in the drawing, the trajectory of the shaft 6 provided on the link member 5 interferes with the upper portion of the side wall of the box body of the base 2 due to the back-and-forth swing of the link member 5, so the swing trajectory of the shaft 6 at this portion. Arc-shaped notch
2c is formed.

Reference numeral 7 denotes a bracket having a substantially C shape in a plan view, which is mounted on a shaft 6 provided on the left and right link members 5, 5, and the upper surface of the bracket 7 is slightly spaced from the front width of the support base 2. A long rectangular plate is attached as a receiving seat 8 for supporting the front half side of a seat shell described below from the lower surface.

On the other hand, the shaft 4 penetrates the box of the support base 2 and is provided so as to project left and right from the side wall surface of the box.
A lower end portion 9a of an arm 9 having a substantially J-shape when viewed from the side is connected and fixed to the left and right protruding portions, and the shaft 4 and the arm 9 are formed so as to integrally rotate. ing. The lower end 9a of the arm 9 is integrally joined to the lower end 9a of the arm 9.
9a is a connecting cylinder portion, 10 is the left and right arms 9, 9
It is a seat that supports the rear half of the seat shell attached to the upper ends 9c and 9c of the above from the lower surface.

The link members 5, 5 supporting the front half of the seat shell are always urged toward the front side of the support base 2 by springs, while the link members 5, 5 are always supported. The following configuration is added to restrain the movement of the.
That is, inside the support base 2, a shaft 11 is attached to the bracket 7, and a gas spring 13 and a washer 12 of a coil spring 14 are connected to each other. The washer 12 has a color-shaped spring. Gas spring 13 through stop 15a
The coil spring 14 and the tip end side of the coil spring 14 are coaxially supported, while the rear end side of the gas spring 13 is provided so as to penetrate the spring stopper 15b.
Supported by 16.

The rear end side of the gas spring 13 is connected to a support beam 17 disposed inside and rearward of the base 2 via a piston rod 13a. Also, the coil spring 14
Is formed so that the repulsive force of the spring 14 can be adjusted by supporting the spring receiver 16 supporting the rear end side thereof by the receiving member 18 having a substantially L-shaped side surface. That is, the receiving member 18 supports the middle portion on a supporting base by a horizontal shaft 18a parallel to the shafts 3 and 4, the upper end portion is applied to the rear surface of the spring receiver 16, and the lower end portion is formed on the supporting base 2. The reaction force of the spring 14 is supported by connecting to the tip of an adjusting screw 19 screwed on the bottom. Reference numeral 19a denotes an operation knob provided on the screw 19, and the lower end side of the receiving member 18 is vertically displaced by the rotation operation of the knob 19a, and the displacement causes the rotational movement of the receiving member 18 about the shaft 18a to move the coil spring 14 forward and backward. The displacement is converted into a directional displacement, and the degree of compression of the spring 14 is adjusted by this.

Since the seat shell 20 for supporting the seat surface of the chair is mounted and supported on the seats 8 and 10 on the front and rear sides of the seat shell configured as described above and its supporting mechanism, ,
This will be described.

As illustrated in FIG. 4, the seat shell 20 is divided into a front half side and a rear half side of the seat surface approximately half the length of the seat surface. The rear half of the shell 20, that is, the rear shell 22, is foldably connected at its dividing line by a hinge 23 having an axis 23a parallel to the axes 3 and 4 described above. Since the shell 20 is a molded product of synthetic resin, the hinge 23 is integrally formed with the front and rear shells 21 and 22. In the present invention, the seat shell 20 may be made of metal or made of wood such as plywood, and the hinge 23 may be made of a member different from the shell 20. Further, whether or not the seat shell 20 is an inner shell of a chair is also optional. Incidentally, in the specific example of the chair of the present invention, when the depth of the seat is set to about 450 mm, the position of the hinge 23 is set within about 260 mm from the front end of the seat, and the seated person is in a normal office work posture. When sitting, the sitting reference point Sp of the person's pelvis P is set so as to always rest on the rear shell 22.

In the illustrated example, the seat shell 20 is formed as a shell in which a cushion material and an exterior material are mounted on the upper surface side, and both front and rear shells are under no load.
21 and 22 are attached to the seats 8 and 10 so as to form the posture and angle shown in FIG. In the example of FIG. 1, the front shell 21 is inclined slightly upward on the front side when viewed from the axis 23a of the hinge 23, and the rear shell 22 is inclined toward the axis of the hinge 23.
The rear side is inclined upward by about 15 degrees when viewed from 23a. In addition, the rear shell 22 is formed to have a large front-rear width. Specifically, when the back shell 22 is seated on the seat shell 20 in a normal office work posture, the pelvis of the seated person is located in the middle of the rear shell 22. Is formed. As a result, the pelvis in the working posture tilts forward due to the forward tilting action of the posterior shell 22, and as a result, the lumbar spine becomes a posture that draws a substantially S-shape in the standing posture of a natural body. The size of the tilt angle can be set to an arbitrary angle in advance.

Both the front and rear shells 21 and 22, and
The hinge 23 has sufficient strength and rigidity to support the weight of the person sitting on the chair and the reaction force of the support mechanism through the seats 8 and 10, and
As an example, in order to support a seat surface on which a person sits and to have a toughness that also deforms according to the movement of the person sitting, FIG.
-It is comprised as shown in FIG.

In the shells 21 and 22, the portions to which the seats 8 and 10 are applied are surrounded by ribs 24 and 25 and are formed in a thick portion 26. Also, a hinge 23 is formed and a shaft 23a is inserted. The portion to be surrounded is also formed in the thick portion 27, while the outer side of the portion surrounded by the ribs 24 of the front shell 21 is formed as an elastically deformable thin portion 28 that is deformed by the load of the seated person. In addition, 29 is an outer peripheral rib formed on the lower peripheral walls of both the front and rear shells 21 and 22, and on the left and right sides of the outer peripheral rib 29 of the rear shell 22, there are boss-like mounting portions 30 of an armrest to be described later. It is integrally formed with the outer peripheral rib 29 at two locations. Further, on the rear side surface of the outer peripheral rib 29 of the shell 22, mounting holes 31 for a backrest shell 32 to be described later are formed at three positions. In addition, the rear shell
The rib 22 'is also formed on the outer periphery of the upper surface of the 22. Cu is a seating surface formed by a cushion, upholstery, etc. placed on the upper surface of the shell.

The backrest shell 32 is formed in the side cross-sectional shape illustrated in FIG. 5, and is attached to the rear end portion of the shell 22 at an attachment side 33 formed by projecting forward on the inner surface of the lower end portion of the shell 32. It is integrated with the rear shell 22 of the seat shell 20 by being bolted to the hole 31. The back shell 32 and the rear shell 22 may be integrally formed from the beginning.

Since the backrest shell 32 supports the back surface of the person sitting on the seating surface Cu so as to wrap it, the front surface side is curved so that the entire surface has a concave surface with an appropriate curvature, but the degree of curvature is higher. And the bottom is different. That is,
The degree of curvature on the lower front surface side of the backrest shell 32 is large (the curvature is large), the degree of curvature decreases as it goes upward, and the thickness of the shell also decreases.

This is because the lower part of the backrest shell 32 is integrated with or made rigid with the rear shell 22 of the seat shell 20 to firmly hold the waist of the seated person, but above the shell 32, the seated person is seated. This is because the easiness of movement of the shoulder due to the change in the posture of the upper half of the body is allowed, and the flexible movement according to the change in the posture of the upper half of the body is allowed. Mounting surfaces 34 for armrests 35 are formed on the left and right side surfaces of the lower portion of the backrest shell 32. 34a is a bolt hole provided on this surface 34.

The armrest 35 has a substantially rectangular frame shape whose upper surface is formed on a support surface 36 of the elbow, and is also provided with a side surface substantially concave mounting frame 37 supporting the support surface 36. The frame 37 has three bolt holes 37a corresponding to the bolt holes formed in the shells 22 and 32 for mounting the armrests 35. Therefore, the armrest 35 has three bolt holes.
Insert bolts into 37a and install bolt holes 30a and 34a respectively
The rear portion of the rear shell 22 of the seat shell 20 and the lower portion of the backrest shell 32 can be fixed and integrated by interposing this mounting frame 37 by screwing into the. In a chair having no armrests 35, L-shaped coupling members may be attached to the rear side surface of the rear shell 22 and the lower side surface of the backrest shell 32 to fix the relative angle between them.

The chair of the present invention configured as described above is formed into a chair having an appearance as shown in FIG. 9 as an example.
This will be described below with reference to FIG. 9 to 11, Sb is a backrest surface formed on the front surface of the backrest shell 32.

First, the chair of the present invention is in a state where no one is sitting,
That is, in the unloaded state, the rear half of the seat surface Cu, that is, the rear shell 22 of the seat shell 20 has a considerably large front-rear width and is inclined forward by a considerably large angle, here about 15 ° (see FIG. 1). ). When a person M sits on the seating surface Cu in a normal office work posture as illustrated in FIG. 10, the seating reference point Sp of the pelvis P of the seated person M is inevitably near the middle of the rear shell 22. Since it is located above, even if the seat shell 20 is slightly depressed due to its weight, the posture of the pelvis P of the seated person M is
Compared with the conventional chair, the posture becomes closer to the posture of the pelvis P in the standing posture by the natural body, that is, the Pervic support state. Moreover, in addition to this posture of the rear shell 22, the backrest shell 32 is integrated with the rear portion of the rear shell 22 at its lower portion and made rigid, and the seated person M has a large curvature.
Since the lumbar region of the pelvis is wrapped around from both sides, the pelvis P is in the Pervic support state and the backrest shell
It is also effectively held by the bottom of 32.

When the pelvis P of the person M is held in the pervict support state, the upper half of the person's upper body is slightly tilted forward, but if the chest is stretched a little, the lumbar spine L is in its most natural form. It will draw a gentle S-shape. In other words, this posture is the most comfortable posture for the lumbar spine L, which supports the weight of the person M sitting on the chair on the pelvis P, and therefore, performing the office work in this posture is effective even if the work is continued for a long time. It is possible to obtain the unique effect of the chair of the present invention that it is not tired or hardly tired.

In order to relax in the work posture shown in FIG. 10,
As illustrated in FIG. 11, when the occupant M holds his back B toward the backrest shell 32, the upper half of the backrest Sb bends due to the small thickness of the shell 32, and the lower portion of the backrest Sb becomes Since it is integrated with the rear shell 22 through an armrest 35 (not shown in FIGS. 10 and 11), the lower portion of the backrest inner shell 32 and the rear portion of the rear shell 22 of the seat can be changed in their relative angle. Instead, they rotate integrally around the shaft 4 in the clockwise direction (see FIGS. 4 and 11).

When the lower part of the shell 32 and the rear part of the rear shell 22 rotate integrally without changing their relative angles, the front shell 21 is connected to the rear shell 22 via the shaft 23a at the hinge 23. That the front shell 21 is connected to the shaft 3 through the bracket 7 and the link member 5 and the link member 5 receives the pushing force by the coil spring 14 from the rear of the front shell 21. Since the entire shell 20 retracts a little while elastically sinking to the rear side, the seated person M can easily take a comfortable posture in which he / she leans backward. At this time, the pelvis P of the seated person M is
Inner shell with backrest that reclines (sinks) integrally
Since the lower part of 32 and the rear shell 22 rotate integrally, relative positional deviation does not occur, and clothes do not turn up. When the body is raised, the seat 14 and the backrest return to their original positions by the action of the spring 14.

In the chair of the present invention which operates as described above, since the gas spring 13 is normally set to free, the backrest Sb is tilted backward, the seat surface Cu is depressed, and the chair is returned to its original posture. , Can be arbitrarily repeated by the backward tilting force of the person M and the force of the spring 14. However, by locking the free motion state of the piston of the gas spring 13, these motions can be locked at an arbitrary inclination of the backrest Sb or the amount of depression of the seating surface Cu.

That is, if the valve opening / closing needle 13b provided coaxially with the rod 13a of the gas spring 13 is pushed in by the operating lever 13c, the flow of gas inside the gas spring 13 is blocked. The locked state is realized. Reference numeral 13d is a toggle for advancing and retracting the position of the lever 13c, and this toggle 13d can be arbitrarily operated from the outside by a shaft 13e.

[0034]

The chair of the present invention is as described above, and in the chair having the backrest and the seat plate, and the seat plate is formed so as to sink in the rear side, the seat shell forming the seat plate is provided. When it is divided into two parts in the front and rear, and the rear half of the divided seat shell is seated on the seat plate in a normal office work posture,
The seated person's pelvis is formed to have a size that can be comfortably placed, and the rear half of the seat shell can swing up and down about the dividing point within a range of about 15 degrees to -5 degrees with respect to the horizontal plane. Since it is formed as described above, the office work posture among the sitting postures can be maintained in a so-called pervic support state, and thus the long working posture can be maintained with less fatigue.

Further, the waist of the seated person is held from both sides and the rear surface by the shaping of the backrest shell, with the pelvis at the time of sitting in the office work posture resting on the rear shell, and the lower part of the backrest shell. Since the relative angle between the seat shell and the rear half of the seat shell is fixed, when the seated person leans backward from the office work posture, the seated person's pelvis and lumbar spine tilt backward together with the backrest shell and the seat shell. As a result, it is almost never that the clothes on the waist are turned up.

Further, since the structure of the mechanism for realizing the seated posture as described above is extremely simple, even a high-performance chair can be formed with a small number of parts, which results in assemblability and cost. In any of the above, it is more advantageous than conventional products.

[Brief description of drawings]

FIG. 1 is a side sectional view showing an example of a mechanism of a chair of the present invention.

FIG. 2 is a plan view of the mechanism shown in FIG.

3 is a front view of the mechanism of FIG. 1. FIG.

FIG. 4 is a side sectional view showing an operation example of the mechanism of FIG.

FIG. 5 is a side sectional view of a seat and a backrest portion of the chair of the present invention.

FIG. 6 is a plan view of a seat shell.

7 is a view of the seat shell of FIG. 6 taken along the line AA.

8 is a BB arrow view of the seat shell of FIG.

FIG. 9 is a perspective view of an example of the chair of the present invention.

FIG. 10 is a side sectional view showing a seated state of the chair of the present invention according to the office work posture.

FIG. 11 is a side sectional view showing a seated state in which the chair of the present invention is tilted rearward.

[Explanation of symbols]

 1 column 2 support base 3,4 horizontal shaft 5 ring member 6 shaft 7 bracket 8 and 10 seat 9 arm 11 shaft 12 seat washer 13 gas spring 13a piston rod 13b opening and closing needle 13c operation lever 13d toggle 13e Axis 14 Coil springs 15a, 15b Spring stop 16 Spring bearing 17 Support beam 18 Support member 18a Axis 19 Adjustment screw 19a Knob 20 Seat shell 21 Front shell 22 Rear shell 23 Hinge 23a Axis 24, 25 Rib 26, 27 Thick section 28 Thin part 29 Outer peripheral rib 30 Mounting part 30a Bolt hole for mounting 31 Mounting hole 32 Backrest shell 35 Armrest 36 Elbow support surface 37 Mounting frame 37a Bolt hole

Claims (6)

[Claims] 1. In a chair having a backrest and a seat plate, the seat plate being formed so as to sink in the rear side, the seat shell forming the seat plate is divided into two parts, front and rear, and the divided seat shell. The rear half of the seat shell is formed to have a size such that the pelvis of the seated person can be comfortably seated when seated on the seat in a normal office work posture, and the rear half of the seat shell is about 15 degrees to the horizontal plane. A chair formed so that it can swing up and down about the dividing point within a range of about -5 degrees. 2. A seat shell of a chair, which is bifurcated in the front and rear and is hinged to be bendable at its divided portion, is made to protrude forward of the seat shell at the upper part of a pillar that is provided upright with legs provided at the lower part. In the chair supported by the support base provided, the vicinity of the front end portion on the front half side of the divided seat shell is supported by the support base.
The front end portion of the seat is supported by a connecting link member that is erected so as to be able to swing back and forth, and the rear half of the seat shell is provided with a shaft at the tip end portion that is swingable back and forth in the middle portion of the support base. Means for supporting the rear end of a supporting arm of a required length pivotally mounted via the link arm, and for constantly urging the link member on the pivot shaft of the connecting link member or the supporting arm toward the forward tilt side. By connecting and providing the front half side of the seat shell in a substantially horizontal or a minute angle rear descending posture, the rear half side of the seat shell is arranged in a larger front descending posture, and the rear half side of the seat shell A chair characterized in that it is formed by fixing the back end member and the lower end side at a required angle. 3. The chair according to claim 2, wherein an angle between the rear half of the seat shell and the lower end of the backrest member is fixed by an armrest member or a connecting member. 4. The chair according to claim 3, wherein the backrest member is formed such that the curved curvature of the inner surface of the lower half side is larger than the curved curvature of the upper half side. 5. The chair according to claim 2, wherein a support surface of the seat shell for connecting the connection link member and the support arm is formed thicker than the other surface. 6. The chair according to claim 1, wherein the front edge on the front half side of the seat shell is formed so as to be flexible under the load of a seated person.