JPH11169254A - Chair - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily confirm the degree of initial elasticity of a coil spring by visual observation in the stably supported state of the coil spring. SOLUTION: A fourth shaft 22 is rotatably provided at a seat receiving base 2, a rear spring bearing 26 is supported by a cam 25 fitted to the fourth shaft 22. When the fourth shaft 22 is rotated by an operating lever 27, the rear spring bearing 26 longitudinally moves to change the initial elasticity of a coil spring 23. A protrusion 30 provided outward at the fourth shaft 22 is fitted into an oblong hole 31 provided in a side plate 2a of the seat receiving base 2. The set degree of initial elasticity of the coil spring 23 can be confirmed by visual observation from the longitudinal position of the protrusion 30 in the oblong hole 31.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chair in which a backrest or a seat or both are tilted against the elasticity of a spring means (generally a compression coil spring).

[0002]

2. Description of the Related Art In a chair, for example, when a backrest is tilted backward against a coil spring, the elastic support force when leaning against the backrest can be changed according to the weight and physique of the user. Therefore, the initial elastic force of the coil spring is often adjusted.

As means for adjusting the initial elastic force of the coil spring, for example, as is widely known in Japanese Utility Model Publication No. 511791, for example, one spring receiver supporting one end of the coil spring is attached in the vertical direction. Is supported by a wedge body that is movable in a triangular shape when viewed from the side, and this wedge body is moved up and down by a bolt that is operated to rotate from below the seat base,
In many cases, the initial elastic force of the coil spring is adjusted steplessly by moving one of the spring supports in the direction of expansion and contraction of the coil spring.

[0004]

However, in such a structure in which the initial elastic force is adjusted by simply rotating the bolt, the photograph for rotating the bolt is exposed below the seat base. Therefore, it is not possible to visually recognize how much the initial elastic force of the coil spring is set. For this reason, it is necessary to repeat the work of rotating the bolt by an appropriate amount, then sitting on a chair, leaning on the backrest and checking the hardness, and adjusting the initial elastic force of the coil spring is troublesome. Was. Although the range in which the initial elastic force of the coil spring can be adjusted (that is, the movement stroke of the spring receiver) is limited, it is not possible to visually check whether the initial elastic force of the coil spring can be adjusted in a desired direction. There was also an inconvenience that it was not possible to determine whether or not the adjustment was possible without first rotating the.

On the other hand, the seat base is generally formed in a box shape with an upward opening, and one end of the coil spring is supported by a spring support shaft penetrating through the left and right side plates of the seat base. Utilizing the hole formed in the seat base to fit the spring support shaft into an arc-shaped long hole extending in the front-rear direction of the chair, and moving the spring support shaft back and forth along the arc-shaped long hole. Accordingly, the initial elastic force of the coil spring is adjusted. In this case, the initial elastic force of the coil spring can be visually recognized based on the position of the spring support shaft in the elongated hole, so that there is no problem that occurs when the bolt is rotated and adjusted.

However, if the hole into which the spring support shaft is fitted is formed in an arc shape, another member for supporting the spring support shaft so as to be able to move back and forth in a stable state is required, and the structure becomes complicated. A new problem arises. An object of the present invention is to make it possible to visually recognize the initial elastic force of a coil spring without complicating the structure.

[0007]

In order to achieve the above object, the present invention provides a method of mounting a backrest or a seat body or both on a seat base having an upward opening provided at an upper end of a leg so as to be tilted in the front-rear direction. A spring means for elastically supporting the tilt of the backrest or the seat body or both is arranged in the seat base so as to expand and contract substantially in the front-rear direction, and further, a lever or the like is operated from the outside of the seat base. A chair provided with adjusting means for adjusting the initial elastic force of the spring means by means of the control means, wherein the adjusting means and the seat base are visually inspected for changes in the attitude or position of the adjusting means by operation of the lever or the like. To provide an indicator means that can be confirmed by "."

[0008]

With this configuration, when adjusting the initial elastic force of the spring means such as the coil spring by operating the lever or the like, the initial elastic force of the spring means can be determined by visually observing the index means. Since it is possible to check at a glance whether the degree of hardness is sufficient and whether it can be adjusted in the direction desired by the user, the initial elastic force of the spring means can be adjusted easily. Further, since the spring supporting shaft is immovably supported by the seat base, the spring means can be supported in a stable state. Therefore, the supporting structure of the spring means (in other words, the adjusting means of the initial elastic force of the spring means) ) Is not complicated.

According to the second aspect of the present invention, the initial elastic force of the spring means can be adjusted stepwise by a one-touch operation of rotating the operation handle to rotate the cam. In addition, the structure becomes simpler because another member is not required as the index means.

[0010]

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a right side view of the chair. As shown in this figure, the chair has a leg 1 having a built-in gas cylinder for lifting, a seat receiving base (lower base) 2 fixed to the upper end of the leg 1, A seat 3 and a backrest 4 are attached to the seat base 2 so as to be tiltable rearward.

FIG. 2 is a plan view showing the seat body 3 by imaginary lines.
3 (A) is a sectional view taken along the line IIIA-IIIA of FIG. 2, and FIG. 4 is a sectional view taken along the line IV-IV of FIG.
It is a sectional view, as shown in these figures, while the seat receiving base 2 is formed in a U-shaped front cross section that is open upward, while the lower surface of the seat body 3 is attached to the seat receiving base 2 from above. U-shaped upper base (bracket) with a downward open front section
The left and right side plates 5a, 5 of the upper base 5 are fixed.
b and the right and left side plates 2a, 2b of the seat base 2.
By passing the first shaft 6 through the front end of the
Allows tilting backwards.

In this case, for example, as shown in FIGS. 3A and 3C, the insertion hole 7 of the seat base 2 in which the first shaft 6 is fitted is formed as a long hole which is gradually inclined rearward. , Seat 3
Is set to be able to retreat while tilting backward. A bearing 8 made of synthetic resin or the like is mounted in the insertion hole 7. The backrest 4 is provided with a pair of left and right back support rods 9 extending rearward on both left and right sides of the seat support base 2, and a tubular portion 9 a is provided at a front end of the back support rod 9. The second shaft 10 passes through the two left and right side plates 2a and 2b.
Therefore, the back support rod 9 and the backrest 4 can tilt in the front-rear direction about the second shaft 10. The second shaft 10 is located slightly forward of the leg 1.

The right and left back support rods 9 are provided with support pieces 9b, which are located outside the rear ends of the left and right side plates 5a and 5b of the upper base 5, and project upward. The third shaft 11 passes through the left and right plates 5a and 5b.
Therefore, when the backrest 4 tilts rearward, the seat body 3 retreats while gently tilting rearward. As shown in FIGS. 2 and 4, a collar 12 for positioning is fitted on the third shaft 11.
The left and right back support rods 9 are reinforced plates near the support pieces 9b.
Connected at 13.

As shown in FIGS. 2 and 3 (A), a reinforcing frame 14 having a downward opening extending between the left and right side plates 2a and 2b is fixed to the rear portion of the seat receiving base 2 and is built into the leg 1. The operating pin 15 of the gas cylinder is exposed from a hole provided in the reinforcing frame 14. On the right side of the upper surface of the reinforcing frame 14 when viewed from the front, an elevating operation lever 16 for pressing down the operation pin 15 of the gas cylinder is received so as to rotate about an axis extending in the front-rear direction of the chair. It is attached by a member 17.

One end of the elevating operation lever 16 extends above the elevating gas cylinder, and the other end protrudes outside the seat base 2. When the elevating operation lever 16 is pulled upward from the outside of the seat base 2, the other end of the elevating operation lever 16 presses the operating pin 15 of the gas cylinder, thereby unlocking the elevating gas cylinder. A switching pin 18 for switching between a free state in which the backrest 4 and the seat body 3 can be tilted and a locked state in which the backrest 4 and the seat body 3 cannot be tilted is fitted to rear portions of the left and right side plates 2a and 2b in the seat receiving base 2.
The switching pin 18 always penetrates the left side plate 5a of the upper base 5, but in this case, as shown in FIG.
The upper base 5 can be tilted rearward regardless of the presence of the switching pin 18 by making a hole formed in the left side plate 5a of the upper base 5 to fit the 18 into a long hole 19 extending along the rearward tilting direction of the seat body 3. On the right side plate 5b of the upper base 5,
An appropriate number (three in the drawing) of lock holes 20 into which the switching pins 18 can be fitted are provided along the rearwardly inclined direction of the upper base 5.

Therefore, in the unlocked state in which the switching pin 18 is retracted from the right side plate 5b of the upper base 5, the upper base 5 and the seat body 3 can freely tilt backward regardless of the presence of the switching pin 18, while the switching is performed. In the locked state where the pin 18 is inserted into any one of the lock holes 20, the seat body 3 and the backrest 4 are held in a state in which the seat body 3 and the backrest 4 cannot be tilted back and forth. That is, the seat 3 and the backrest 4 can be locked in a plurality of postures having different inclination angles thereafter.

A portion of the seat base 2 between the left and right side plates 2a and 2b, which is slightly forward of the second shaft 10, has a fourth shaft (spring support shaft) extending in the left-right direction with a rectangular cross section (other shapes may be used). ) 22 is rotatably mounted, and the fourth shaft 22 and the first
A coil spring (compression coil coil spring) 23 is arranged between the first shaft 6 and the shaft 6.
While supporting the entirety of the coil spring 23, the rear end of the coil spring 23 is supported by a cam 25 and a rear spring receiver 26 attached to the fourth shaft 22.
One end of the fourth shaft 22 protrudes largely toward the outside of the seat base 2, and an operation lever 27 is provided at one end thereof.

FIG. 5 is a perspective view of a main part. As shown in FIGS. 5, 2 and 3, the fourth shaft 22 is connected to the left and right side plates 2a and 2b of the seat base 2 via left and right bearings 28. It is rotatably supported. The cam 25 is fitted on the fourth shaft 22 so as to rotate integrally with the fourth shaft 22. Fig. 3 (B) is a diagram.
It is a partial enlarged view of 3 (A) (cross section is omitted),
As shown in FIGS. 3B, 3A and 5, a plurality of (six in the figure) support surfaces 29 are formed on the outer peripheral surface of the cam 25. Each support surface 29 is set so that the distance from the axis O is sequentially different. Also, the perpendicular H of each support surface 29 is set to pass through the axis O without fail so that the coil spring 23 can be supported in a stable state.

Guide cylinders 25a are integrally formed on both left and right ends of the cam 25, and U-shaped guide feet 26a formed in right and left ends of the rear spring receiver 26 are formed in the guide cylinders 25a. Is fitted. The rear surface of the rear spring receiver 26 is provided with a projection 26b that contacts the support surface 29 of the cam 25. Therefore, when the cam 25 is rotated by rotating the fourth shaft 22, the rear spring receiver 26 moves gradually toward and away from the first shaft 6, whereby the initial elastic force of the coil spring 23 changes.

In order to keep the coil spring 23 stable, the rear spring receiver 26 has a hole into which the coil spring 23 fits deeply.
26c is open, and a rod 23a on which the coil spring 23 is fitted is formed integrally with the front spring receiver 24. The coil spring 23 and the front and rear spring supports 24, 26 are the left side plate of the seat support base 2.
It is located close to 2a, and as part of the indicator means,
On the side surface of the rear spring support 26, a projection 30 protruding toward the left side of the seat support base 2 is integrally provided.
A long hole 31 into which the protrusion 30 is movably fitted to the left side plate 2a
(It may be a notch hole). It is preferable to set the gap between the inner surface of the elongated hole 31 and the projection 30 so that there is not much gap.

As shown in FIG. 5 and FIG. 6, the projection 30 is provided on the tip end surface of the projection 30 and the outer surface of the left side plate 2a of the seat base 2.
May be displayed by an appropriate means such as engraving. Further, instead of or in addition to the scale 32, another strength display indicating the stage of the initial elastic force, such as characters such as strength or softness, may be given. The cam 25 and the front and rear spring receivers 26 may be made of synthetic resin or metal (preferably made of synthetic resin from the viewpoint of workability).

In the above configuration, when a person leans against the backrest 4 in the unlocked state in which the switching pin 18 is retracted, the seat body 3 and the backrest 4 tilt backward against the elasticity of the coil spring 23. In this case, the hardness of the coil spring 23 can be adjusted by rotating the operation lever 27 to change the initial elastic force. As described above, in adjusting the initial elastic force of the coil spring 23 by rotating the operation lever 27, it is possible to visually recognize the position of the projection 30 of the rear spring receiver 26 in the elongated hole 31 so that the coil spring 23 Since the hardness of the coil spring 23 can be identified at a glance, the initial elastic force of the coil spring 23 can be quickly adjusted, and even when the desired hardness cannot be changed, the fact can be immediately understood. hand,
Useless operation can be avoided.

The rear seat base 2 is used as an index means.
The projection 30 is integrally provided on the seat base 2, while the slot 31 is
Since only a hole is formed, no other member is required, and the structure is correspondingly simple. Further, since the fourth shaft 22 is supported by the seat base 2 in a stable state, the coil spring
The 23 support structure is also simple. Incidentally, since the cam 25 is considerably smaller than the lateral width of the seat base 2, the fourth shaft 22 has a first shaft located closer to the right side plate of the seat base 2 as shown in FIGS. A spacer 33 and a second spacer 34 located between the first spacer 33 and the cam 25
Is fitted. The first spacer 33 is fitted on the bearing 28, and a snap ring (push nut) 35 for retaining is fitted on the tip of the fourth shaft 22, while the cam is
The left guide cylinder portion 25a of the 25 is fitted on the left bearing 28, and the fourth shaft 22 is fitted with a snap ring 35 for retaining. This makes assembly and disassembly easier.

That is, although the snap ring 35 is easy and inexpensive to prevent the snap ring 35 from coming off, when the fourth shaft 22 is positioned at a predetermined position, the snap ring 35 is in close contact with the outer surface of the bearing 28. Removal is troublesome. On the other hand, when the clip-type second spacer 34 that is attached to and detached from the fourth shaft 22 against elasticity is provided as in the present embodiment, when the second spacer 34 is removed, FIG.
As shown by a dashed line, even when the cam 25, the first spacer 33, and the right bearing 28 are still fitted to the fourth shaft 22, the fourth shaft 22 is largely projected outside the seating base 2. Or you can pull it in and out
By attaching and detaching the snap ring 35 while the fourth shaft 22 is slid as indicated by the one-dot chain line, the snap ring 35 can be easily attached and detached. By attaching the spacer 34, it is held so as not to slide with the fourth shaft 22, so that assembly and disassembly are very simple.

Since there is no need to consider the clearance for attaching and detaching the snap ring 35, the snap ring
There is also an advantage that the 35 can be brought into close contact with the outer surface of the bearing 28, so that the overall dimensional accuracy can be improved and each member can be accurately positioned. The pivotal support structure of the back support rod 9 by the third shaft 11 is as shown in FIG. That is, while the third shaft 11 is inserted into the bearing 37 mounted on the seat base 2, the cylindrical portion 9 a provided on the back support rod 9 is provided with a bush having a spacer portion 38 a.
38, the third shaft 11 is fitted into the bush 38, and further, in the hollow portion of the cylindrical portion 9a, a snap ring 39 is fitted to the end of the third shaft 11 so that the third shaft 11 cannot be removed. And a detachable cap 40 is attached to the cylindrical portion 9a of the left and right back support rod 9. With this configuration,
Since the third shaft 11 is not exposed to the outside, the appearance is clear and the appearance is excellent.

The third shaft 11 may be shared with the fourth shaft 22. In the case of a structure in which the backrest 4 is tilted backward by moving the fourth shaft with the first shaft 6 fixed,
The adjusting means may be provided on the first shaft 6. Although the illustrated embodiment tilts the seat body and the backrest integrally, the present invention can be applied to a chair in which only the backrest tilts backward, or the backrest and the seat body tilt rearward against separate coil springs. It can also be applied to chairs. The present invention is also applicable to a chair having a structure in which a seat body tilts forward.

Further, as the index means, the seat base 2
Is provided on the outer surface of the coil, a scale extending around the axis of the fourth axis is provided, and a needle extending to the scale is provided on the fourth axis, and the initial elastic force of the coil spring is adjusted at the position (posture) of the needle. For example, the form may be different from the form shown in the drawing, such as to allow visual recognition. 9 and 10 show a second embodiment. FIG. 9 is a partial plan view, and FIG. 10 is a sectional view taken along line XX of FIG. In this embodiment, a wedge effect is used as a means for adjusting the initial elastic force of the coil spring 23.

That is, a wedge member 43 having an inverted trapezoidal side cross section is disposed at the front (or at the rear) of the seat base 2, and the wedge member 43 has a knob 44 a penetrating from below the seat base 2. The operation bolt 44 is screwed in, and one end surface of the wedge member 43 is supported by a fixed guide body 45 fixed to the seat base 2, while the other end surface of the wedge member 43 is supported by a movable spring receiver 46 in which the coil spring 23 is fitted. When the bolt 44 is rotated to move the wedge member 43 up and down, the movable spring receiver 46 moves back and forth by the wedge action, and the initial elastic force of the coil spring 23 changes.

A projection provided on the side surface of the wedge member 43
30 is fitted in a vertically long hole 31 formed in the side plate 2a of the seat base 2, and also in this case, the protrusion in the long hole 31 is used.
Depending on the position of 30, the initial elastic force of the coil spring 23 can be visually confirmed. A compression coil spring is generally used as the spring means, but an elastic body such as rubber can also be used.

[Brief description of the drawings]

FIG. 1 is a right side view of a chair.

FIG. 2 is a plan view in a state where a seat body is indicated by a virtual line.

3A is a sectional view taken along the line IIIA-IIIA in FIG. 2, and FIG.
(C) is a partial view of (A).

FIG. 4 is a sectional view taken along line IV-IV of FIGS. 2 and 3;

FIG. 5 is an exploded perspective view of a main part.

FIG. 6 is a view taken along the line VI-VI of FIG. 4;

FIG. 7 is a sectional view showing a pivotal support structure of the back support rod.

FIG. 8 is a diagram showing an assembling procedure.

FIG. 9 is a partial plan view of the second embodiment.

10 is a sectional view taken along line XX of FIG. 9;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 leg 2 seat base 3 seat body 4 backrest 5 upper base 6 1st axis 9 backrest support rod 10 2nd axis 11 3rd axis 22 4th axis (spring support axis) 25 cam 26 rear spring support 29 support surface 30 projection 31 Slot

Claims (2)

[Claims] 1. A backrest or a seat or both are attached to a seat base having an upward opening provided at an upper end of a leg so as to be tilted in a front-rear direction, and the backrest or the seat or both are mounted in a seat base. A spring means for elastically supporting the tilt is arranged so as to expand and contract substantially in the front-rear direction, and furthermore, an initial elastic force of the spring means is adjusted by operating a lever or the like from the outside of the seat base. A chair provided with a means, wherein the adjusting means and the seat base are provided with index means for visually confirming a change in posture or position of the adjusting means by operation of the lever or the like. . 2. A cam according to claim 1, wherein said adjusting means is fitted on a fixed spring support shaft supporting one end of a spring, and an outer peripheral surface of said cam and one end of spring means (compression coil spring). And a plurality of support surfaces for the spring receiver are formed on the outer peripheral surface of the cam along the circumferential direction, and a distance from the axis of the spring support shaft to each support surface is formed. By setting the spring support differently, when the cam rotates, the spring receiver is set to move in the direction of expansion and contraction of the spring means. On the other hand, as the index means, the spring receiver has a projection protruding toward the outside of the seat base. And a side plate of the seat receiving base is provided with an elongated hole in which the projection of the spring receiver is slidably fitted.