JP2002355136A - Braking and locking device for chair - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a locking device for switching between a free state in which a backrest is allowed to lean backward and the locking state in which it is not allowed to move, which achieves a lightweight and rugged structure as well as improves locking reliability. SOLUTION: Each side plates 5a of a base 5 has a lengthwise slot 7, through which a slide shaft 8 is inserted via a bush 9. Right and left spring bearing 21 and 22 are fitted to the slide shaft 8, in which sliding parts 31 provided there are inserted into the bush 9. These right and left spring bearing 21 and 22 are provided with stoppers 23, 24, and 25 to stop the tilt of a backrest 4 in such a way that the bush 9 inserted into the slot 7 blocks the movement of the slide shaft 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a rocking chair having a backrest that tilts backward against spring means.
The present invention relates to a lock device that switches a backrest between a free state in which the backrest can be freely tilted and a locked state in which the backrest cannot be tilted.

[0002]

2. Description of the Related Art There is a synchro-type chair in which a seat and a backrest tilt in conjunction with each other. In this chair, in order to allow the backrest and the seat to tilt rearward, an upwardly opening opening fixed to the upper end of a leg post is provided. A left and right longitudinal slide shaft is inserted through the letter-shaped base so as to be movable back and forth.

[0003] As a locking device for this synchro-type chair, a hook is fixed to the bottom of a base, and a rotatable stopper is provided to be hooked on the hook, and the stopper is rotated by operating a lever, so that a free state is achieved. And a lock state.

Japanese Patent Publication No. 64-6763 discloses a chair of the type in which only the backrest tilts backward. A bracket-type stopper is provided on a tilting frame to which the backrest is attached, and a pin provided on a seat is provided on the bracket-type stopper. A locking device adapted to lock by hitting is described.

[0005]

When a person leans against a backrest in a state in which the lock cannot be tilted backward, a load acts greatly on a member constituting the lock device as a tensile force or a bending moment. In a state where the backrest is locked in the backward inclined posture, the elastic force of the spring always acts as a tensile force or a bending moment on members such as the hook and the stopper.

In any case, since a large load is applied to members such as hooks and stoppers, there is a risk that durability will be reduced. To avoid this, each member must be made of metal and have a sturdy structure. Then, there is a risk that the weight of the chair will increase. There is also a risk that the lock may be released due to a jumping phenomenon due to vibration or the like.

[0007] In particular, if the backrest is configured to be locked in a plurality of postures, the shape of the members constituting the locking device becomes complicated, and there is a further concern about insufficient lock release due to reduced strength or vibration.

The object of the present invention is to improve such a situation.

[0009]

In a chair provided with legs, a seat, and a backrest, a base having an upward opening in front view and having left and right side plates is attached to an upper end of the legs, and left and right side plates of the base are respectively front and rear. A long hole extending long in the direction is provided, and a slide shaft inserted in the long hole so as to be able to move back and forth is supported by spring means, so that at least the backrest is inclined backward against the spring means. is there.

The present invention relates to a chair of this type,
A stopper is provided inside the base to prevent or allow movement of the slide shaft by fitting into and removing from the elongated hole, and an interlocking mechanism to fit and remove the stopper from the elongated hole to the base by lever operation. .

According to a second aspect of the present invention, in the first aspect, a first stopper which fits into the elongated hole when the slide shaft is advanced,
By providing a second stopper that fits into the elongated hole when the slide shaft is retracted, the backrest is allowed to be selectively locked in a state in which the backrest is tilted forward and a state in which the backrest is tilted backward, while the interlocking mechanism is A slider that slides in the left-right direction by a lever operation, and a spring that transmits the movement of the slider to the stopper.

[0012]

According to the present invention, the backrest (both the backrest and the seat in the case of a synchro-type chair) can be locked so as not to be tilted by preventing the slide shaft from moving back and forth with the stopper.

In this case, in the locked state, the load acting on the slide shaft only acts as a compressive force on the stopper inserted into the elongated hole, so that the member such as the stopper is made of a light material such as synthetic resin. As a result, high durability can be ensured. As a result, it is possible to reduce the weight without impairing the durability.

Further, while the load acts on the stopper from the front-back direction when the chair is viewed from the front, the stopper moves in the left-right direction when the chair is viewed from the front. Are intersected with each other, the stopper does not come out of the elongated hole even if vibration or the like acts on the stopper by the slide shaft. In other words, the lock is not accidentally released, and the reliability of the lock is high.

In the case of Japanese Patent Publication No. 64-6763, the lever positions are different between the free state, the backward inclined position, and the non-backward inclined position, which makes the lever operation troublesome.

According to a second aspect of the present invention, when the backrest is selectively locked in two postures, that is, a rearwardly inclined position and a non-rearwardly inclined position, two types of stoppers are pressed by springs. Therefore, when the backrest is in a desired posture and the lever is in the locked posture, the stopper corresponding to that posture is automatically fitted into the elongated hole to be in the locked posture.

That is, according to the second aspect, the backrest can be locked in any of the rearwardly inclined posture and the non-rearwardly inclined posture by a simple operation of merely setting the lever in the locked posture. Is easy.

[0018]

Next, embodiments of the present invention will be described with reference to the drawings.

(1). Outline of Chair FIG. 1 is a front view of the chair, FIG. 2 is a side view, FIG. 3 is a longitudinal side view in which main parts are omitted, and FIG. 4 is a plan sectional view in which main parts are omitted. First, an outline of the chair will be described based on these drawings.

The chair includes a leg 1 on which a pillar (gas cylinder) 2 is erected, a seat 3 and a backrest 4. At the upper end of the pillar 2, a base 5 formed in an open U-shape in cross section when viewed from the front is fixed.

The seat 3 is attached to an intermediate fitting 6 provided with side plates 5a located on the left and right sides of the base 5, while
At the front of the left and right side plates 5a of the base 5, substantially long longitudinal holes 7 are formed, and the side plate 6a of the intermediate fitting 6 is connected to a slide shaft (first shaft) 8 inserted into the long holes 7. are doing. A bush 9 made of a synthetic resin is mounted in the elongated hole 7.

The backrest 4 is a back support (tilt frame) 10.
Attached to. The back strut 10 has a front end connected to the base 5 by a second shaft 11 so as to be capable of tilting rearward, and a middle part in the front and rear directions is rotatably connected to a side plate 6 a of the intermediate fitting 6 by a second shaft 11. Have been.

Therefore, when the backrest 4 is tilted backward, the seat 3 is also tilted backward while retreating. Inside the base 5 is a slide shaft 8
A coil spring 13 that elastically supports the backward movement of the coil is disposed. The coil spring 13 is supported from the rear of the fixed spring receiver 14, and the fixed spring receiver 13 has an adjustment knob 14 for changing the initial elastic force.

The base 5 is provided with a lifting lever 16 for operating the pillar 2 and a locking lever 17 for locking the tilt of the backrest 4. Reference numeral 18 shown in FIG. 3 is a cover.

As shown roughly in FIG. 4 by a dashed line, a lock device 20 which is operated by operating the lock lever 17 is provided inside the base 5. This point will be described next with reference to FIGS.

(2) Outline of Locking Device Next, the locking device will be described with reference to FIGS.

FIG. 5 is a plan view showing a state where members are separated, and FIG.
Is a plan view in an assembled state. As shown in these figures, the lock device includes a right spring receiver 6 disposed substantially on the right side of the inside of the base 5 and a right spring receiver 6 disposed on the substantially left side of the inside of the base 5. The left spring receiver 7 disposed, the first right stopper 23 mounted on the right spring receiver 21, the first left stopper 24 mounted on the front of the left spring receiver 22, and the second first stopper 24 mounted on the rear of the left spring receiver 22. 2 stopper 25, right slider 26 mounted on right spring receiver 21, and left slider 27 mounted on right spring receiver 21 and left spring receiver 22
And an operation cam 28 mounted on the right spring receiver 21.

In this embodiment, each member is made of synthetic resin. The members except for the stoppers 23, 24 and 25 constitute an interlocking mechanism described on the backrest.

The slide shaft 8 penetrates through the right spring receiver 21 and the left spring receiver 22, and both have a stepped portion 29 so as to overlap with each other in a plan view. It is arranged between the side plates 5a so as not to shift left and right.

FIG. 7 is an exploded perspective view of a main member, and FIGS.
1 is a perspective view of each member viewed from another direction. FIG.
FIG. 13 is a sectional view taken along the line XII-XIII of FIG. 6, and FIG. 14 is a side view showing the relationship between the left spring receiver 22 and the left slider 27. The shape and the mutual relationship will be described.

(3) Right Spring Support and Right First Stopper As shown in FIGS. 7 and 8, on the back surface of the right spring support 21, a spring stopper 30 for holding the coil spring 13 so as not to be displaced.
Is protruding. On the right side of the right spring receiver 21,
A substantially rectangular slide portion 31 that fits slidably in the bush 9 of the base 5 is formed, and the slide shaft 8 penetrates the slide portion 31.

As shown in FIG. 8, the inner surface of the bush 9 is also substantially rectangular, so that the right spring receiver 21 is held non-rotatably about the axis of the slide shaft 8, and as a result, the coil The spring 13 can be supported in a stable state.

At the right end of the right spring receiver 21, a stopper receiving part 32 is provided on the front side of the slide part 31 so that the right first stopper 23 is slidably fitted in the left and right directions. The first right stopper 23 is formed in a rectangular shape so as to fit inside the bush 9, and the first stopper 23 is connected to the bush 9 in a state where the backrest 4 is fully inclined backward (a state in which the slide shaft 8 is completely retracted). 9 can be fitted inside.

A flange 33 is provided at the left end of the right first stopper 23, and a bank portion 34 is provided in the stopper receiving portion 32 of the right spring receiver 21 for restricting a movement stroke of the stopper 33 when the flange 33 comes into contact therewith. I have. The right first stopper 23 is connected to the right first stopper 2.
The right and left slide is accurately guided by the fitting of the guide groove 35 formed in the third and the guide protrusion 36 formed in the right spring receiver 21.

Guide ridge 3 of right first stopper 23
A recess 37 is formed in a portion opposed to 6, and a spring receiving projection 39 into which one end of a first torsion spring 38 fits is provided in the recess 37.

A vertically elongated guide groove 35 extending vertically is formed in the leftward portion of the right spring receiver 21, and a vertically long engagement hole 41 communicating with the vertically elongated guide groove 40 is formed in a left side plate of the vertically elongated guide groove 40. Is formed.

(4) Right Slider As shown in FIG. 7, the right slider 26 includes a pair of upper and lower claws 42 extending rearward, and a forward projection 43. On the other hand, a pair of upper and lower horizontal guide grooves 44 extending in the left-right direction is formed in a part of the right spring receiver 21 on the left side of the vertically long guide groove 40, as shown in FIG.
The upper and lower claws 42 of the right slider 26 are engaged with the horizontal guide grooves 44 against elasticity.

Thus, the right slider 26 is attached to the right spring receiver 21 so as not to be disengaged and slidable left and right. A recess 45 is formed at the base of the forward projection 43 of the right slider 26 and opens upward and rightward. Due to the presence of the recess 45, the other end of the first torsion spring 38 is connected to the forward projection 43. Can be fitted.

The right slider 26 and the right first stopper 23
There is a space between the right slider and the right slider 2
6 moves left and right through the first torsion spring 38, the right first stopper 23 moves left and right in the same direction, and even if the right first stopper 23 contacts the bush 9 and cannot move, the right slider 26 is The first torsion spring 38 can be moved leftward in a deformed state.

(5) Working Cam As shown in FIGS. 7 and 9, a forward-facing nose 46 is formed at a substantially middle portion between the left and right of the working cam.
6, a hole 47 into which the tip of the lock operation lever 17 fits.
Is vacant.

As can be understood from FIG.
7 is a first bent portion 17a extending parallel to the left side plate 5a of the base 5, and a second bent portion 17 extending parallel to the slide shaft 8.
b, and the tip of the second bent portion 17 b is inserted into the hole 47 of the operation cam 28. The lock operation lever 17 can be rotated about the first bent portion 17a, and therefore, by operating the lock operation lever 17, the operation cam 28 can be moved up and down.

As shown in FIG. 9, on the back surface of the operating cam 28, upper and lower guide pieces 48 which fit into the vertical guide grooves 40 of the right spring receiver 21, and hooks which are hooks in plan view which fit into the engagement holes 41. 4
9 are protruded. The claw 49 can be engaged with the engagement hole 41 by deformation against the elasticity. As already understood, when the lock lever 17 is rotated, the operation cam 28 is guided by the vertically long guide groove 35 of the right spring receiver 21 to move up and down.

On both sides of the operating cam 28 with the nose portion 46 interposed therebetween, a pair of oblong holes 5 extending in an inverted C shape when viewed from the front are formed.
0, and the forward projection 43 of the right slider 26 is fitted in the oblique hole 50 on the right as shown in FIG.

The right slider 26 can be moved left and right by operating the locking lever 17 to move the operation cam 28 up and down by the guide action of the oblong slot 50.

(6) Left Spring Receiver As shown in FIGS. 5 and 6, the left spring receiver 22 is arranged in close contact with the left side plate 5a of the base 5. The left spring receiver 22 is formed concentrically with a rectangular slide portion 31 that slidably fits on the bush 9 and a rectangular bearing portion 52 that extends toward the right spring receiver 21. A part 29 is formed.

Since the right spring receiver 21 and the left spring receiver 22 are fitted to each other, the elastic force of the coil spring 13 is also supported by the left spring receiver 22 (in such a sense, the left spring receiver 22). Terminology).

As shown in FIG. 7 and FIG.
A guide ridge 36 is provided on the outer peripheral surface of the bearing portion 52 in FIG.

For example, as can be easily understood from FIG.
A pair of front and rear stopper receiving portions 32 in which the left first stopper 24 and the second stopper 25 fit slidably in the left and right directions are provided on both front and rear sides of the left spring receiver 22 across the bearing portion 52.

The both stopper receiving portions 32 have basically the same structure as that of the right spring receiver 21, and the stopper 2
A bank portion 34 for regulating the strokes of 4, 25 is provided. The left first stopper 24 and the second stopper 25 use the same one as the right first stopper 23. The left first stopper 24 is arranged symmetrically with the right first stopper 23, and the second stopper 25. Are arranged symmetrically with respect to the left first stopper 24.

As can be easily understood from FIGS. 7 and 14, the left spring receiver 22 has a holding claw 53 and a receiving seat 54 for holding the base of the locking lever 17, and the first bending of the locking lever 17. Upper and lower holding pieces 55 and 56 for holding the portion 17a from above and below are provided.

A window hole 57 is formed around the holding claw 53 in the left spring receiver 22. As described above, the locking lever 17 can rotate around the first bent portion 17a. However, as shown in FIG. 14, when the locking lever 17 is rotated downward (in this state, the operation cam 28 The base of the locking lever 17 is held by the holding claws 53 and the receiving seat 54.

On the other hand, when the locking lever 17 is rotated upward (the operating cam 28 is lowered in this state), the base of the locking lever 17 elastically deforms the holding claw 53 and then moves the locking claw 53. It is located above and its state is maintained. That is, the locking lever 17 is selectively held by the elastic force of the holding claws 53 between the locked position in which the locking lever 17 is rotated upward and the free position in which the locking lever 17 is rotated downward.

(7) Left slider As can be understood from FIGS. 13 and 14, the left slider 2
Numeral 7 overlaps the left end of the right spring receiver 21 from the front, and fits into the bearing 52 of the left spring receiver 22 from the outside. For this reason, a guide groove 35 that fits into the guide ridge 36 is formed on the inner surface thereof.
See also).

The left slider 27 has an operation cam 2
A front projection 58 is formed in the left oblong hole 50 of FIG. Therefore, when the operation cam 28 moves up and down, the left slider 27 slides left and right in opposite directions to the right slider 26.

The root of the forward projection 58 of the left slider 27 is formed in an upward recess 59. Therefore, one end of the second torsion spring 60 can be fitted to the forward projection 58. The other end of the second torsion spring 60 is fitted on the spring receiving projection 39 of the left first stopper 24.

As clearly shown in FIG. 10, the rear portion of the left slider 27 has a spring receiving projection 3 extending toward the hollow portion.
9 is provided, and one end of the third torsion spring 61 is fitted to the spring receiving projection 39. The other end of the third torsion spring 61 is fitted on the spring receiving projection 39 of the second stopper 25.

The left spring receiver 22 and the left slider 27 are provided with lateral arms 62 and 63 for preventing the third torsion spring 61 from shifting.

(8). Description of Movement FIG. 15 is a front view in a free state in which the backrest 4 can freely tilt backward. In this state, the locking lever 17 is rotated downward. The cam 28 is descending. Since the left and right sliders 26 and 27 are moving in a direction approaching each other, the stoppers 23, 24,
25 is retreating.

FIG. 16 shows a locked state. In this state, the locking lever 17 is pivoting upward,
Therefore, the operation cam 28 is raised. Since the left and right sliders 26 and 27 move in directions away from each other, the stoppers 23 to 25 are connected to the respective torsion springs 38 and
Pushed through 60,61.

When the lock lever 17 is rotated upward with the backrest 4 fully tilted backward, the first left and right stoppers 23 move forward and fit into the bush 9 at a position on the front side of the slide shaft 8. Thus, the locked state is maintained. In this case, the second stopper 25 is
The left slider 27 is allowed to move to the left only by deforming the third torsion spring 61 without moving forward.

Even if the locking lever 17 is rotated upward before the backrest 4 is fully tilted backward, the first left and right stoppers 23 and 24 are pushed by the torsion springs 38 and 60 and move forward without permission. When the backrest 4 is fully tilted backward,
The left and right first stoppers 23 and 24 are automatically fitted into the bush 9.

When the operation lever 17 is rotated upward in the non-backward tilt state, the second stopper 25 is fitted to the bush 9 on the front side of the slide shaft 8. As a result, the backrest 4 is held so as not to tilt backward.

In the locked state, the load on the back of a person and the elastic force of the coil spring 13 are applied to the stoppers 23, 24,
Since it only acts as a compressive force against 25, high durability can be ensured even with a stopper made of synthetic resin.

The load on the back of the person and the coil spring 13
The stopper 23, 24, 25 moves in the left-right direction while the elastic force of the stopper acts in the front-rear direction, so that even if a vibration is applied to the stopper by a person leaning against a backrest in a locked state, for example, Since no external force acts in the direction of retracting the lock, the locked state can be reliably maintained.

(9). Others The present invention can be further embodied in various ways. For example, the present invention can be applied not only to a chair in which a seat synchronizes with a backrest, but also to a chair in which the backrest only tilts backward. Further, the second axis of the embodiment can be a slide axis.

The spring body is not limited to the torsion spring as in the embodiment, and other types of springs such as a leaf spring and a coil spring can be used.

[Brief description of the drawings]

FIG. 1 is a front view of a chair.

FIG. 2 is a side view of a chair.

FIG. 3 is a longitudinal sectional side view in which main parts are omitted.

FIG. 4 is a plan sectional view in which main parts are omitted.

FIG. 5 is an exploded plan view of the lock device.

FIG. 6 is a plan view of the lock device in a state where members are assembled.

FIG. 7 is an exploded perspective view of a main member.

FIG. 8 is a perspective view of a right spring receiver and a stopper.

FIG. 9 is a perspective view of an operation cam.

FIG. 10 is a perspective view of a left slider.

FIG. 11 is a perspective view of a left spring receiver.

12 is a sectional view taken along the line XII-XII in FIG.

13 is a sectional view taken along the line XIII-XIII in FIG.

FIG. 14 is a side view showing a relationship between a left spring receiver and a left slider.

FIG. 15 is a front view of the lock device in a free state.

FIG. 16 is a front view of the lock device in a locked state.

[Brief description of reference numerals]

 DESCRIPTION OF SYMBOLS 1 Leg 3 Seat 4 Backrest 5 Base 5a Side plate 7 Slot 8 Slider 9 Bush 13 Coil spring 17 Locking lever 20 Locking device 21 Right spring receiver 22 Left spring receiver 23 Right first stopper 24 Left first stopper 25 Second stopper 26 right slider 27 left slider 28 operating cam 38,60,61 torsion spring

Claims (2)

[Claims] 1. A leg having a leg, a seat, and a backrest, and a base having an upward opening when viewed from the front and having left and right side plates is attached to an upper end of the leg. A chair provided with a hole and supported by a spring means so as to be able to move back and forth through the elongated hole, so that at least the backrest is tilted backward against the spring means; A tilt lock for a chair, comprising: a stopper that is fitted into and removed from the elongated hole to prevent or allow movement of the slide shaft; and an interlocking mechanism that allows the stopper to be fitted into and removed from the elongated hole of the base by operating a lever. apparatus. 2. A state in which the backrest tilts forward by providing a first stopper that fits into the elongated hole when the slide shaft is advanced and a second stopper that fits into the elongated hole when the slide shaft is retracted. While allowing to be selectively locked to the backward tilted state, the interlocking mechanism includes a slider that slides in the left and right direction by a lever operation, and a spring body that transmits the movement of the slider to the stopper. The chair lock device according to claim 1.