JPH09173177A - Oscillation mechanism for chair seat plate and seat back - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mechanism capable of arbitrarily locking the interlocked oscillating motion of a seat and a seat back. SOLUTION: An arm member 3 allowed to perform a sinking motion forward around a shaft A is projected forward from the end of a block 2, and the end of a forward seat plate 41 is connected to the end of the arm member 3 via a horizontal shaft B formed to be freely displaceable via a slit C on the forward seat plate 41. In addition, an elastic body 5 for applying a repellent force to separate the plate 41 and a base lock 2 from each other around the shaft B is laid in such a state as clamped from both upper and lower sides with retaining plates 61 and 62. Also, the lower end of a seat back support member 7 for mounting a seat back with a rear seat plate 42 is extended to the lower surface of the seat plate 41, and the intermediate part of the extended part 71 of the support member 7 is connected to the rear end of the forward seat plate 41 via a horizontal shaft D. Then the front end of the extended part 71 is jointed to the arm member 3 via a horizontal shaft E near the shaft A of the arm member 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to a swing mechanism in which a seat plate and a backrest of an office swivel chair are interlocked.

[0002]

2. Description of the Related Art Conventionally, a swinging mechanism for interlocking a seat plate and a backrest in a swivel chair has been known. In the well-known swinging form in which the seat plate and the backrest are interlocked, if the seat plate sinks under the load applied by a person, the backrest tilts backwards in conjunction with this sinking, or the person sits on the backrest. There is one that allows the seat back to sink as the backrest tilts backwards.

However, the manner in which a person hangs on a chair is not limited to the posture that can be dealt with by the conventional swing mechanism. For example, there is a case where a person sits on a chair with such a weight that the front of the seat board sinks to the front side. In such a case, the conventional swinging mechanism does not perform the corresponding operation, or even if a mechanism capable of operating is provided, the structure becomes complicated and the number of components increases, resulting in high cost and assembly. There are various problems such as time-consuming and non-smooth operation.

Further, in a chair in which the seat plate does not sink forward, when the chair is hung on the chair and takes a forward leaning posture, the posture of the seated person becomes unnatural and the abdomen is compressed, and the thighs are tucked. Will be pressed against the seat surface, and the comfort of the chair will not be good. On the other hand, in the case of a user who does not want to swing the seat and the backrest in conjunction with each other as described above, if he / she cannot lock it, the seat becomes rather uncomfortable to sit on.

[0005]

SUMMARY OF THE INVENTION Accordingly, the problem to be solved by the present invention is to allow the seat plate to be sunk on the front side, or on both the front and rear sides, with a simple structure. In addition, it is possible to interlock these sunk movements with the forward or backward tilting movements of the backrest, and to smoothly realize these movements. In addition, in the above-mentioned swinging mechanism, the seat and backrest can be adjusted according to the user's preference. An object of the present invention is to provide a rocking mechanism in which the interlocking rocking motion of (1) can be arbitrarily locked by selecting the front tilt side or the back tilt side.

[0006]

One structure of the present invention, which has been made for the purpose of solving the above-mentioned problems, has a structure in which a base block 2 is arranged at an upper end of a leg support 1 of a chair in a substantially horizontal direction.
The arm block 3 is attached to the base block 2 in front of the column 1 by a horizontal axis A, the rear side of which is horizontal, and is allowed to sink forward around the axis A. It is provided so as to project forward from the tip of the block 2, and a slot C formed through the tip of the arm member 3 or the tip of a front seat plate plate 41 connected to the tip is passed through the block. A front end of the front seat plate plate 41 is pivotally attached to a front end of the arm member 3 through a horizontal axis B that is displaceable in the elongated hole C, and the front seat plate plate is also attached. Between the lower surface of 41 and the upper surface of the block 2, an elastic body 5 made of rubber or the like having a repulsive force acts on the side that separates the plate 41 and the base block 2 from each other about the axis B. , The elastic plate holding plates 61, 62 supported by the shaft B, and sandwiching them from above and below. On the other hand, the lower end side of the backrest support member 7 to which the backrest is attached is provided with a rear seat plate plate 42 located behind the front seat plate plate 41 to provide a lower surface side of the seat plate plate 41. To the front seat plate plate 4 by extending the intermediate portion of the extension portion 71 of the support member 7
1 is pivotally attached to the rear end of the arm member 1 through a horizontal axis D, and the front end side of the extension portion 71 is connected to the arm member 3 by a horizontal axis E in the vicinity of the axis A of the arm member 3. It is characterized by being formed.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A front seat plate plate 41 has an elastic member 5 and its holding member at a front end of an arm member 3 mounted on a base block 2 so as to be swingable only downward by an axis A. Since it is axially connected to the arm member 3 by the shaft B supporting the plates 61 and 62, it can swing downward about the shaft A in front of the front seat plate plate 41. , And can swing up and down around the axis B behind the front seat plate 41. Further, the backrest support member 7 having the rear seat plate plate 42 formed in the extension portion 72 is pivotally attached to the arm member 3 and the front seat plate plate 41 by axes E and D, respectively. Allows the rear seat plate plate 4
2 and the backrest support member 7 can swing in association with the swing of the front seat plate member 41 or the swing of the support member 7. The seat plates 41, 42 support the shaft B when the seat plates 41, 42 swing up and down or when the seat plates 41, 42 and the backrest support member 7 swing together. While being displaced in the hole C, the swing is damped by the elastic body 5 via the holding plates 61 and 62.

A shaft A having an arm member 3 pivotally attached to the base block 2 or a shaft provided at a rear portion of the base block 2;
A gas spring 11 is fixedly installed between the shaft F provided at the rear end of the extension portion 71 of the backrest support member 7 so as to fix the distance between the two shafts, and the gas spring 11 is turned off. Both the front and rear seat plate plates 41, 42 and the backrest support member 7 can be rocked or interlocked with the front tilt, the back tilt, or the back tilt only.

[0009]

Embodiment An embodiment of the mechanism of the present invention will be described with reference to the drawings. 1 is a perspective view of an example of the swing mechanism of the present invention, and FIG. 2 is FIG.
1 is a side cross-sectional view in which no load is applied to the mechanism of FIG.
The rear side of the front seat plate plate 41 of this mechanism is most depressed, and the rear seat plate plate 42 and the backrest mounting member 7
1 is a side sectional view in a state of being most rearwardly tilted, FIG. 4 is a side sectional view in a front tilted state of the mechanism of FIG. 1, FIG. 5 is a perspective view of another example of the swing mechanism of the present invention in FIG. 1, and FIG. 5 is a side sectional view showing a state in which no load is applied in the mechanism of FIG. 5, FIG. 7 shows that the rear side of the front seat plate plate 41 of the mechanism of FIG. 5 is most depressed, and the rear seat plate plate 42 and the backrest mounting member 7 are shown. FIG. 8 is a side sectional view of the mechanism of FIG. 5 tilted rearmost, and FIG. 8 is a side sectional view of the mechanism of FIG.

In FIGS. 1 to 4, reference numeral 1 denotes a pole-like leg support of a rotary chair for office work, for example, by a gas spring (not shown) inserted in the support 1,
The height can be freely changed within a certain range. The height of the support column 1 may be adjusted by a telescopic structure other than the gas spring.

Reference numeral 2 denotes a base block which is attached to the upper end of the support column 1 and has a substantially box-shaped cross section.
On the front side of a, two tongue-shaped upper and lower receiving seats 2b are formed, and the width of a front seat plate plate 41, which will be described later, is formed in front of the pillar 1 in the vicinity thereof. A horizontal bearing oriented parallel to the direction is formed.

Numeral 3 is an arbor having a substantially concave cross section when viewed from the front.
As for the arm member 3, the arm member 3 has a rear end side of the side walls 3a standing upright on the left and right sides of the arm member 3 and an axis A which is horizontal to the bearing of the block 2.
On the other hand, a long hole C is formed at the front end side of the side wall 3a, and a front end side of the front seat plate plate 41 is pivotally connected to a horizontal shaft B passing through the long hole C. The elongated hole C may be provided on the front end side of the seat plate 41. Which side is provided is arbitrary.

Thus, the front seat plate 41 is a plate-shaped plate on the upper surface of which a front half of an appropriate seat plate (not shown) is arranged, and seen from the front. A side wall 41a is formed on the left and right sides of the arm member 3, and a side wall 41a is formed on the front end side of the side wall 41a so as to be displaceable with respect to the arm member 3 by an axis B passing through a slot C on the front end side of the arm member 3. The rear end side of the side wall 41a is attached to the middle portion of the side wall 71a of the extension portion 71 of the backrest supporting member 7, which will be described later, and the shaft D
Are pivotally connected. A rear seat plate 42 is formed on the upper surface of the rear side of the extension 71 of the support member 7 so as to form a seat plate with the front seat plate 41. ing. Each axis A, B, D is horizontal and parallel.

Here, the front and rear of the front seat plate plate 41 are provided on the front side of the arm member 3 and the intermediate portion of the extension portion 71 of the backrest support member 7 via axes B and D, respectively. In connection with the connection, in the above example, the elongated hole C was formed on the tip side of the side wall 3a of the arm member 3, but in the present invention, instead of this elongated hole C,
An elongated hole H indicated by a one-dot chain line in FIG. 2 is provided in the side wall 71a of the extension 71 of the backrest support member 7 or the rear part of the side wall 41a of the front seat plate plate 41, and the shaft D is formed in the elongated hole H. May be supported. In the present invention, it is sufficient to provide either the elongated hole C or the elongated hole H, and which is provided is arbitrary.

On the axis B of the front seat plate plate 41,
A block member made of rubber or synthetic rubber sandwiched between a plate member facing the lower seat 2b of the base block 2 and a plate member facing the lower surface of the plate 41. An elastic body holding plate 61 for supporting the body 5,
It is arranged as 62. The elastic body 5 is also supported by the shaft B by penetrating the shaft B.

The block-shaped elastic body 5 has a support plate 61 whose upper and lower surfaces are pushed down by a front seat plate plate 41 which moves up and down about an axis B, and a seat 2 of a base block 72.
Since it is sandwiched by the holding plate 62 supported on the upper surface of b, it acts as a cushioning member for the vertical swing of the seat plate plate 41.

Reference numeral 7 is a backrest support member to which a backrest (not shown) is attached on the upper side, and the lower portion is a seat plate plate 4.
Is formed on the extension portion 71 that is curved and extended so as to be positioned along the lower surface of the extension portion 71. Side walls 71a that are long arms when viewed from the side are extended and formed on both left and right sides of the extension portion 71, and Rear seat plate play on the upper surface of the latter half of 71
42 is formed. The side walls 71a have the base
Above the block 2, the rear portion of the side wall 3a of the arm member 3 is formed here so that it can be sandwiched from the outside. Further, the tip of the side wall 71a is formed to have a length positioned in front of the axis A so as to be coupled with the arm member 3.

The backrest supporting member 7 having the rear seat plate 42 is pivotally attached to the base block 2 by the axis A at the tip of the side wall 71a of the extension 71 thereof. Is connected to the arm member 3 which is allowed to rotate only in the counterclockwise direction in the figure by a horizontal axis E, and the intermediate portion of the side wall 71a of the extension portion 71 has an axis D.
Is pivotally connected to the rear end side of the side wall 41a of the front seat plate plate 41.

In the above structure, the holding plate for the elastic body 5 is
The rear end of the base 62 is provided with two seats 2b of the base block 2.
Is supported between the lower surface by an adjusting screw 9 screwed on a screw receiver 8 formed on the seat 2b above the base block 2 and a support nut member 10 screwed on the screw 9. There is. Reference numeral 9a denotes a screw rotation operation knob provided at the lower end of the screw 9, but the knob may be a lever.

With the above-described structure, when the adjusting screw 9 is rotated to advance the nut 10 upward, the rear end side of the lower holding plate 62 strongly clamps the elastic body 5. The repulsive force of can be strengthened.

With the above construction, both the front and rear seat plate plates 41, 42 are integrated with the arm member 3 centering on the axis A, and the plate 41 is sunk on the front side. Rocking and swinging in which the sinking operation of the front seat plate plate 41 around the axis B at the rear and the tilting motion of the backrest support member 7 integrated with the rear seat plate plate 42 are interlocked. An example of the mechanism is formed. Since the mechanism of the present invention is provided with a mechanism for locking the interlocking swing motion, this point will be described next.

In the above-described mechanism of the present invention, since the swinging motion of the seat and the back is interlocked, as an example, a horizontal shaft F erected on the front side of the side wall 71a of the extension 71 of the backrest support member 7 is connected. Are connected by a gas spring 11, and a valve (not shown) in the cylinder of the gas spring 11 is opened, so that the gas freely flows before and after the piston in the cylinder to allow the piston rod of the gas spring 11 to flow. By freeing the advancing / retreating of 11a and closing the valve, the gas flow of the spring 11 is blocked and the advancing / retreating of the rod 11a is restrained.
1 is fixed to the rearward sinking around the axis B and the rearward tilting motion of the backrest support member 7 integrated with the rear seat plate plate 42, and the seat plate plates 41 and 42 and the backrest support member are fixed. 7
I fixed the interlocking of.

In the embodiment shown in FIGS. 1 to 4, the rear end of the cylinder of the gas spring 11 is connected to the shaft F, and the tip end side of the piston rod 11a is connected to the shaft A through the connecting bracket 12. At the same time, an operating rod 11b for operating the opening and closing of the valve is provided coaxially with the rod 11a so as to project from the rod 11a. And this operating rod 1
An operation piece (not shown) for operating the rod 11b is provided on the front surface of 1b. Here, by pushing this operation piece, the operation rod 11b is retracted to open the valve in the cylinder, and the operation piece is pushed in. When the rod 11b is not present, the rod 11b holds the advanced state and the closed state of the valve in the cylinder is maintained.

The mechanism of the present invention constructed as described above operates as follows. Now, both front and rear seat plate plates 4
When a person hangs on the seat sheet (not shown) provided on the first and the second seats 42 and the operating piece of the gas spring 11 is retracted, the load of the person is not including the seat sheet. , Both rear seat plate plates 41, 42. The load applied to the seat plate plates 41 and 42 which receives the load is partly absorbed by the deformation of the elastic body 5, but the deformation and the holding plate 6
Since it is supported by the receiving seat 2b of the base block 2 through the bending of the base blocks 1, 62, it is also supported by the base block 2 with the resilience of the elastic body 5. In other words,
The front and rear seat plate plates 41, 42, which have been subjected to a vertical load, are elastically supported by the arm member 3 at a position slightly rearward from the middle through the holding plate 61 and the elastic body 5. As well as
Since the arm member 3 is supported by the receiving seat 2b via the elastic body 5 and the holding plate 62, the load can be elastically supported.

The front seat plate plate 41 has a rear end with a base.
The arm member 3 supported by the axis A on the block 2
Is supported by the shaft B passing through the elongated hole C on the front end side of the seat back plate, and the rear end side of the seat plate plate 41 is supported by the arm member 3 via the shaft E. Since the rear seat plate plate 42 is formed on the upper surface of the support member 7 and is connected to the middle of the side wall 71a in the extension portion via the shaft D, both seat plate plates 41, 42 are armed. Is supported by the repulsive force of the elastic body 5 with the member 3 interposed,
These plates 41 and 42 are capable of submerging and swinging around the axes A and B on either the front or rear side thereof.

When the front seat plate 41 is sunk at the front end side, this sunk operation is integrated with the arm member 3 through the shaft B and the elongated hole C, and the shaft A is centered. This causes the arm member 3 to sink in the front side against the repulsive force of the elastic body 5 and raise the plate 41 rearward, and at the same time, the seat plate plate 41 and the arm member 3 are caused. With respect to the sinking operation on the front side about the axis A, the side wall of the extension portion 71 in which the rear seat plate plate 42 is formed in the backrest support member 7 is formed.
Since 71a is sunk in the front side about the axis A on the front end side (portion of the axis E), and the lifting operation of the rear end side of the side wall 71a is caused, the rising portion (backrest) of the support member 7 is caused. ) Is rotated forward and tilted, and by this series of operations, the rearward lifting operation of the seat plate plates 41 and 42 and the forward tilting operation of the backrest support member 7 are synchronized.

On the other hand, front and rear seat plate plates 41, 42
Is depressed at its rear end side, that is, when it rotates in the clockwise direction in FIG. 3, this depression action is an arm member that cannot rotate in the clockwise direction due to the action of the seat 2b in the base block 2. Since it operates centering on the axis B passed through the elongated hole C in FIG.
Due to the connection relationship between the shaft 41 and the extension 71 of the backrest support member 7 by the axes D and E, the rearward tilting motion of the support member 7 is synchronously brought about. At this time, only the rear end side of the front seat plate plate 41 sinks downward about the axis B because the bottom wall 3b of the arm member 3 is the seat 2b of the base block 2. If it touches the outer surface,
This is because the clockwise rotation about the axis A of the frame member 3 is prevented. The above-mentioned synchronous operation is performed by the backrest support member 7 or the rear seat plate 42 which is integral with the backrest support member 7.
Even when they are loaded and tilted rearward, the rearward sinking motion of the front seat plate plate 41 following this inclination is brought about.

Both the front and rear seat plate plates 41, 4 as described above
Among the swinging movements of the backrest support member 7 and the backrest support member 7, the rearward sinking operation of the front seat plate plate 41 about the axis B locks the gas spring 11 installed between the axes A and F. By doing so, it is possible not to interlock. That is, in the above example, the gas spring 11 is locked by pushing the operating piece that had opened the valve of the cylinder to push the operating rod 11b forward (toward the left in the figure). When
The gas spring 11 is in a locked state in which the flow of gas in the cylinder is blocked and the piston cannot move forward or backward. When the gas spring 11 is in the locked state, the rear end side of the extension portion 71 integrated with the rear seat plate 42 which was rotatable around the shaft E, that is, the shaft F side is fixed. As a result, the synchronized rearward inclination of both the front and rear seat plate plates 41 and 42 and the support member 7 is fixed.

The extension 71 of the backrest support member 7 is fixed to the axis F and the axis A by fixing the rotation of the extension 71 about the axis E.
Of the base 71 and the side wall 71a of the extension 71 are connected to each other by the shaft D, and the seat 2b of the base block 2 serves as the center of the shaft A. The seat plate plate 4 connected to the arm member 3 which is prevented from tilting backward at the axis B is also prevented from sinking rearward, so that the front seat plate plate 41 is formed.
The backrest support member 7 and the backrest support member 7 are fixed so that they cannot be tilted and rocked in synchronization with each other.

On the other hand, a backrest support member integrated with a front seat plate plate 41 and a rear seat plate plate 42 in which the above-described synchronized seat depression and back tilt are fixed by locking the gas spring 11. The members 7 and 7 are locked by the gas spring 11 and are kept as one body, and the front seat plate 41 is sunk in front of the front seat plate 41 about the axis A, and the sunk operation is integrated. The forward leaning motion of the backrest support member 7 is allowed while receiving the action of the elastic body 5.

In the mechanism of the present invention of the above-described embodiment, the operation of the gas spring 11 is locked or unlocked, whereby the front seat plate plate 41 and the rear seat plate plate 42 are integrated with the backrest support member 7. It is possible to lock or release the synchronized backward tilting and swinging state according to the user's intention, so that the seat plate plates 41, 42 sink to the rear side according to the user's preference. It is possible to fix the retracted state and the rearwardly inclined state of the backrest support member 7 which is interlocked therewith in desired states.

Next, in the mechanism of the present invention, as illustrated in FIGS. 5 to 8, the elastic body 5 of the previous embodiment and its holding plate 6 are used.
Instead of 1, 62, it may be formed by a structure using a torsion spring 51 and a holding block 63 for holding the spring 51 with respect to the axis B. In this case, the starting end 51a of the torsion spring 51 is the holding plate 6 of the previous embodiment.
It is applied to the lower surface of the front seat plate 41 in the same manner as 1.
The end 51b of the spring 51 is supported by the seat 2b of the base block 2 via a spring receiver 51c. Further, the holding block 63 is formed of rubber or plastic into a cylindrical shape to hold the twisted portion of the spring 51 at a predetermined position with respect to the axis B, and is inserted inside the twisted portion of the spring 51. . As a result, the torsion spring 51 acts almost the same as the holding plates 61 and 62 of the previous embodiment and the block-shaped elastic body 5 sandwiched between the plates. 5 to 8, the same reference numerals as those in FIGS. 1 to 4 indicate the same members or the same parts.

In the mechanism of the present invention described above, although not shown, the gas spring 11 is installed between the shaft F and the shaft G which is set rearward of the leg support 1 of the base block 2, so that the seat plate is formed. Not only is the lock of the plate 41, 42 depressed toward the rear side, but also the plate 41, 42 concerned.
You can also lock down the front side of the. That is, the axis A is located to the right of the leg support 1 of the base block 2 in FIG. 2 or FIG.
By providing a shaft G parallel to the gas spring 11 and installing a gas spring 11 between the shaft G and the shaft F, the gas spring 1
The locking of No. 1 locks not only the sinking of the seat plate plates 41, 42 to the rear side but also the sinking of these plates 41, 42 to the front side.

In the mechanism of the present invention of the previous embodiment described with reference to FIGS. 1 to 4, the upper and lower holding plates 61 and 62 are
The standing walls 61a and 62a provided on both sides of them are supported on the shaft B. However, even if the holding plates 61 and 62 are replaced by a single hairpin-shaped plate, the same operation as in the previous embodiment is achieved. A swing mechanism is obtained.

The constituent members of the mechanism of the present invention described above are the support column 1, the base block 2, the arm member 3, the two seat plate plates 41, 42, the block-shaped elastic body 5, and the holding plate. -Since the shape of each member, such as the grate 61, 62, the torsion spring 51, and the support member 7 for the backrest, is simple, it can be easily made by an appropriate means such as metal casting, forging, press working, or molding of synthetic resin. Can be manufactured.

[0036]

The present invention is as described above.
A front seat plate plate is an arm member pivoted at its front end to a base block, and a rear seat plate plate is an extension of the backrest support member. Is integrally formed with the front seat plate plate and is pivotally attached to the rear end portion of the front seat plate plate, and is axially connected to the arm member. The end portions of the front and rear seat plates are pivotally moved in the same direction in the front and rear directions by being axially connected to a mating member supported through a shaft that passes through an elongated hole. Will be supported as much as possible,
It operates as follows. That is, the backrest support member, to which the extension part integrally formed with the front seat plate plate and the rear seat plate plate located at the rear part is axially connected, interlocks backwardly. Since the rear seat plate plate and the backrest support member have a larger rear tilt than the front seat plate plate, the front and rear seat plate plates are tilted at substantially the same angle. , It can be tilted forward or backward or rocked back and forth to fit the posture of the seated person.

Further, a shaft having an arm member pivotally attached to the base block, or a shaft provided at the rear of the leg support of the base block and a shaft provided at the front side of the extension of the backrest support member. Since a gas spring is installed on the front of the seat, which allows the distance between both shafts to be fixed and open freely, the front seat plate plate is sunk in the rear according to the posture of the person sitting on the chair and the rear seat plate plate is linked with it. -Reciprocal tilt of the backrest side integrated with the front or back, or sinking both front and back of the front seat plate and the back and front tilt of the back seat having the rear seat plate interlocked therewith are linked. It is possible to smoothly realize the sinking of both the front and rear seat plate plates.

In addition to this, the front seat back plate is sunk in the rear, or both front and rear, and the back seat is tilted backward or forward or rearward with the rear seat plate plate interlocked therewith. Since the gas spring can be fixed by locking, the seat plate and the backrest can be inclined depending on the preference of the seated person, which is extremely useful in use. Moreover, the mechanism for performing the above-described operation has a small number of parts and is simple, which is advantageous in manufacturing.

Further, the front and rear seat plate presses according to the present invention.
The frontward or rearward sinking operation is an operation accompanied by cushioning by the repulsive force of the block-shaped elastic body interposed between the front seat plate plate and the base block, and this operation is also performed. Since the long hole absorbs the displacement of the shaft that accompanies the movement of the seat plate, the seat plate can be smoothly and flexibly driven by the forward or backward tilted posture of the person, and the sinking state according to the user's preference. The unique property is that the can be fixed in that state. Particularly, in this fixing, the gas spring is arranged by selecting a supporting point on the base block side between the extension portion of the backrest supporting member and the base block at any position before and after sandwiching the supporting leg. By doing so, it is possible to arbitrarily select the state in which only the depression of the seat plate toward the rear side is locked, or the state in which the depression is locked in both the front and rear directions, so that a chair with good sitting comfort can be obtained. Can be easily provided.

[Brief description of the drawings]

FIG. 1 is a perspective view of an example of a swing mechanism of the present invention.

FIG. 2 is a side sectional view showing a state where no load is applied to the mechanism shown in FIG.

FIG. 3 is a side sectional view of the mechanism of FIG. 1 in a state in which a rear side of a front seat plate plate 41 is most depressed, and a rear seat plate plate 42 and a backrest mounting member 7 are most inclined rearward.

FIG. 4 is a side sectional view of the mechanism of FIG. 1 in a forward tilted state.

5 is a perspective view of another example of the swing mechanism of the present invention in FIG.

6 is a side sectional view showing a state in which no load is applied to the mechanism of FIG.

7 is a side cross-sectional view of the mechanism of FIG. 5 in a state in which the rear side of the front seat plate plate 41 is most depressed, and the rear seat plate plate 42 and the backrest mounting member 7 are tilted most rearward.

8 is a side sectional view of the mechanism of FIG. 5 in a forward tilted state.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 support | pillar 2 base block 3 arm member 41 front seat plate plate 42 rear seat plate plate 5 block-shaped elastic body 61,62 holding plate 7 backrest support member 71 extension part 8 screw receiving 11 gas Spring A, B, D, E, F, G axis C, H oblong hole

Claims (3)

[Claims] 1. A base block 2 is attached to an upper end portion of a leg support 1 of a chair in a substantially horizontal direction.
Of the arm member 3 whose front portion is pivotally attached to the front side of the column 1 by a horizontal axis A and which is allowed to sink forward around the axis A from the front end portion of the block 2. It is provided so as to project and can be displaced in the elongated hole C through an elongated hole C formed in the distal end portion of the arm member 3 or the distal end portion of the front seat plate plate 41 connected to the distal end portion. The tip of the front seat plate plate 41 is pivotally attached to the tip of the arm member 3 via a horizontal axis B, and the lower surface of the front seat plate plate 41 and the upper surface of the block 2 are connected. Between the plate 41 and the base block 2, an elastic body 5 made of rubber or the like having a repulsive force acting on the side separating the plate 41 and the base block 2 from each other about the shaft B is supported on the shaft B. Elastic body holding plate
The upper and lower sides of the backrest support member 7 to which the backrest is attached are arranged on the lower end side of the backrest support member 7,
A rear seat plate plate 42 located behind the front seat plate plate 41 is provided to extend to the lower surface side of the seat plate plate 41, and an intermediate portion of the extension portion 71 of the support member 7. Is pivotally attached to the rear end portion of the front seat plate plate 41 through a horizontal axis D, and the front end side of the extension portion 71 is connected to the rear end portion.
The horizontal axis E near the axis A of the frame member 3
A swinging mechanism of a seat plate and a backrest of a chair, characterized in that the swinging mechanism is connected to the arm member 3. 2. The swing mechanism according to claim 1, wherein the base is
The axis A in which the arm member 3 is pivotally attached to the block 2, or
A shaft G provided on the rear side of the leg column 1 of the base block 2 and a shaft F provided on the rear end side of the extension portion 71 of the backrest support member 7 are fixed and openable. A swinging mechanism of a seat plate and a backrest of a chair, characterized by having a moth spring 11. 3. The gas spring 11 has a rear end side on the axis F of the backrest support member 7 and a front end side on the base block 2 side.
3. The swinging mechanism for the seat plate and the backrest of the chair according to claim 1, wherein the swinging mechanism is connected to the shaft A or the shaft G of FIG.