JP2009082529A - Chair - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve the function of automatically adjusting reaction force when tilting a backrest 2 by a configuration simpler than conventional one. <P>SOLUTION: The chair includes a reaction force mechanism 3 for applying the reaction force to the backrest 2 when the backrest 2 is tilted, a fluid pump 4 disposed under a seat surface, and a reaction force adjusting mechanism 5 for varying the size of the reaction force that the reaction force mechanism 3 demonstrates to the backrest 2 according to the pressure of fluid flowing out from the fluid pump 4 which receives the load of a sitting person through a seat 1. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a chair that can automatically adjust a reaction force when tilting a backrest according to the weight of a seated person.

As a chair for increasing the reaction force when tilting the backrest with respect to a seated person having a large weight, those disclosed in the following patent documents are known. This chair has an interlocking mechanism that lowers the seat by an amount corresponding to the weight of the seated person and operates in relation to the amount of the lowering, and the elastic resistance of the spring means that generates a reaction force is transmitted via the interlocking mechanism. Adjust mechanically.
JP 05-184432 A

  The interlocking mechanism of the chair as in the above example causes an increase in the number of parts, and the shape of the constituent members of the interlocking mechanism, and further, the interlocking mechanism itself tends to be complicated. The complexity of the mechanism increases the influence of friction generated in each part of the mechanism due to the weight of the seated person, and prevents smooth tilting of the backrest.

  The present invention made in view of the above is intended to realize an automatic reaction force adjustment function when the backrest is tilted with a simpler configuration.

  In order to solve the above-described problems, the present invention provides a seat, a backrest that can tilt with respect to the seat, a reaction force mechanism that applies a reaction force to the backrest when the backrest tilts, and the seat. The magnitude of the reaction force exerted against the tilted backrest according to the fluid pressure flowing out from the fluid pump disposed under the seating surface and the fluid pump receiving the load of the seated person via the seat A chair comprising a reaction force adjusting mechanism to be varied was configured.

  The fluid pump and the flow path (pipe, tube piping) for guiding the fluid pressure discharged from the fluid pump to the vicinity of the reaction force mechanism can be easily implemented as compared with the interlock mechanism in the chair in the above example. Effective in simplifying the force adjustment mechanism.

  The fluid pump is, for example, a fluid bag that receives a load of a seated person and deforms so that the volume is reduced and discharges the fluid, and the reaction force adjusting mechanism has, for example, one end connected to the fluid bag to load the seated person. A pipe through which the fluid flowing out is received and a telescopic device connected to the other end of the pipe to expand and contract under the pressure of the fluid.

  For example, the reaction force adjusting mechanism displaces an action point of the reaction force applied to the backrest by the reaction force mechanism using the fluid pressure. In this case, it is easy to change the distance between the action point and the center of rotation of the backrest by moving an elastic member that generates a reaction force using the fluid pressure. .

  In addition, when the backrest is in the standing position, the distance between the action point and the center of rotation of the backrest is allowed, and when the backrest tilts from the standing position, the center of rotation of the action point and backrest is allowed. If a locking mechanism that suppresses the variation in the distance between the elastic member and the backrest is interposed, the magnitude of the reaction force suitable for the seated person's body when the seated person is seated The reaction force does not increase or decrease unexpectedly when the backrest is tilted.

  Alternatively, instead of displacing the point of action of the reaction force applied to the backrest by the front reaction force mechanism, the support position for supporting the reaction force mechanism may be displaced using the fluid pressure.

  According to the present invention, it is possible to realize an automatic reaction force adjusting function when the backrest is tilted with a simpler configuration than the conventional one.

  <First Embodiment> An embodiment of the present invention will be described with reference to the drawings. As shown in FIGS. 1 to 3, the chair according to the present embodiment includes a seat 1, a backrest 2 that can be tilted with respect to the seat 1, and a reaction force against the backrest 2 when the backrest 2 is tilted. In response to the fluid pressure flowing out from the fluid pump 4 that receives the load of the seated person via the seat 1. And a reaction force adjusting mechanism 5 that varies the magnitude of the reaction force exerted by the.

  The seat 1 is formed by attaching a cushion, a tension member, and the like forming a seating surface to the seat receiver 11, and is supported by the legs 6.

  The backrest 2 is formed by attaching a cushion, a tension member, or the like that forms a backrest surface to the back support 21 and is pivotally supported on the main body side of the chair, for example, the seat 11 or the leg 6.

  The reaction force mechanism 3 uses an elastic member 31 such as a gas spring, a coil spring, a leaf spring, or a torsion bar. One end side of the elastic member 31 is in direct contact with the backrest 2 directly or through another member. The other end side of the elastic member 31 is movably supported on the main body side of the chair. The elastic member 31 is elastically deformed when the backrest 2 is tilted by a seated person, and acts on the backrest 2 using the elastic force as a reaction force. In the illustrated example, a gas spring is assumed as the elastic member 31, and a roller 32 that rolls on the rear end side is provided so as to contact the lower end portion of the back support rod 21 via the roller 32, and the front end side is rotated. It is attached to the seat 11 so that it can move or slide.

  The fluid pump 4 is a fluid bag that is deformed by a load of a seated person and discharges fluid, particularly air. However, it does not prevent the use of a gas other than air, or a liquid such as water or oil, which hardly causes a volume change due to compression.

  The reaction force adjusting mechanism 5 varies the magnitude of the reaction force by displacing the reaction point of the reaction force that the reaction force mechanism 3 acts on the backrest 2. The reaction force adjusting mechanism 5 has an actuator 51 that is an expansion / contraction device that communicates with the fluid pump 4 through a pipe 52 such as a pipe or a tube and that is operated by a fluid pressure discharged from the fluid pump 4. The actuator 51 is, for example, a fluid pressure cylinder 51 including a piston that moves forward and backward by fluid pressure. Thus, the forward / backward movement of the piston causes displacement of the point of action of the reaction force applied to the backrest 2. In this embodiment, the point of action is displaced by moving the elastic member 31 that is an element of the reaction force mechanism 3. Also, an auxiliary elastic member 53 is provided between the main body side of the chair and the gas spring 31 to assist the return of the gas spring 31 and the action point F to the original positions. The auxiliary elastic member 53 elastically deforms and stores an elastic force as the gas spring 31 and the action point F are displaced from the original position, and biases the gas spring 31 toward the original position with the elastic force.

  When the backrest 2 is regarded as a lever, the rotation center C of the tilting backrest 2 is a fulcrum, the backrest surface or the backrest 21 is the power point of the tilting operation of the backrest 2, and the backrest 2 and the reaction force mechanism 3 The contact point F becomes an action point. When the seated person is seated 1, the fluid pump 4 that receives the load of the seated person contracts to discharge the fluid and drive the piston of the fluid pressure cylinder 51. The piston protruding from the cylinder 51 moves the gas spring 31 against the urging force of the auxiliary elastic member 53, and as a result, the action point F is displaced away from the fulcrum C. The fluid pressure discharged from the pump increases as the weight of the seated person increases, and the amount of protrusion of the piston, and thus the amount of displacement at which the action point F moves away from the fulcrum C, also increases as the weight of the seated person increases. FIG. 2 shows a state in which a seater having a relatively light weight is seated, and FIG. 3 shows a state in which a seater having a relatively heavy weight is seated. Thereby, the reaction force that opposes the tilting operation of the backrest 2 is increased or decreased.

  When the seated person stands, the contracted fluid pump 4 expands to suck in the fluid, and the piston is immersed in the cylinder 51, and the gas spring 31 and the reaction point F of the reaction force are returned to their original positions. Return. FIG. 1 shows this state.

  Second Embodiment As shown in FIGS. 4 to 6, a locking mechanism 7 is provided between the rear end side of the gas spring 31 and the backrest 2, and a reaction force is transmitted via the locking mechanism 7. Can be configured to. The locking mechanism 7 allows a variation in the distance between the action point F and the fulcrum C when the backrest 2 is in a predetermined standing position, and the action point F and the fulcrum C when the backrest 2 tilts from the standing position. It plays a role of deterring fluctuations in distance.

  The locking mechanism 7 includes, for example, a locking shaft 72 provided on the rear end side of the gas spring 31 and a rack-shaped or internal gear-shaped locking member 71 provided at the lower end portion of the back support rod 21. . The locking shaft 72 is a substantially horizontal shaft extending in the width direction, and supports the roller 33 at the shaft end. The locking member 71 extends in a direction away from the fulcrum C, and a plurality of concave grooves 711 are formed on the surface facing the locking shaft 72. The locking shaft 72 can selectively engage with the concave groove 711 at any one of the steps. When the locking shaft 72 is locked in the concave groove 711, the reaction point F acts there. On the side of the locking member 71, a guide rail 12 that can be rolled or slid by contact with the roller 33 is provided. These rails 12 are supported on the main body side of the chair so as not to follow the tilt of the backrest 2.

  When the backrest 2 is in the standing position, the locking shaft 72 is separated from the concave groove 711 of the locking member 71. FIG. 4 shows this state, and the gas spring 31 is allowed to move freely with respect to the locking member 71 through expansion and contraction of the cylinder 51. Therefore, the distance between the action point F and the fulcrum C is variable according to the weight of the seated person. When the backrest 2 tilts from the upright position, the locking member 71 rotates around the fulcrum C in a direction approaching the locking shaft 72, and the locking shaft 72 has a concave groove 711 at any stage of the locking member 71. Engage with. FIG. 5 shows this state, and the gas spring 31 is prohibited from freely moving with respect to the locking member 71. Therefore, the distance between the action point F and the fulcrum C remains unchanged. That is, the angle of the locking member 71 changes as the backrest 2 tilts backward. At this time, the rear end side of the gas spring 31 that receives the operation force from the locking member 71 moves in a direction approaching the fulcrum C. Can be prevented. Incidentally, it is preferable to provide an elastic member (not shown) that applies an initial reaction force to the backrest in the standing position separately from the gas spring 31.

  <Third Embodiment> In the embodiment shown in FIGS. 7 to 11, first, the front end side of the gas spring 31 is pivotally attached to the main body side of the chair, and the rear end side thereof is turned up and down.

  At the lower end of the back support rod 21, a contact portion 22 that comes into contact with the roller 34 existing at the rear end of the gas spring 31 is provided. The contact portion 22 has a partial arc-shaped contact surface centered on the rotation center of the gas spring 31, that is, the front end.

  When the seated person sits down, the fluid from the fluid pump 4 flows into the cylinder 51, the piston advances from the cylinder 51, and pushes the rear end side of the gas spring 31 downward. Therefore, as shown in FIG. 8, the contact point between the roller 34 and the contact portion 22, which becomes the reaction point F of reaction force, is displaced downward. Since the contact surface of the contact portion 22 has a partial arc shape when viewed from the side, the length of the gas spring 31 does not expand or contract even if the gas spring 31 rotates while the backrest 2 is in the standing position. The resistance force that the gas spring 31 receives from the contact portion 22 when the spring 31 is rotated is small (a degree of friction) and can be easily rotated in any direction. Of course, if the backrest 2 starts to tilt, the gas spring 31 is pushed and contracted by the contact portion 22 that rotates about the fulcrum C.

  However, when the backrest 2 is started to be tilted, the possibility that the gas spring 31 is unexpectedly rotated and the action point F is shifted along the contact surface of the contact portion 22 cannot be denied. On the other hand, also in this embodiment, the locking mechanism 7 is interposed between the gas spring 31 and the backrest 2.

  As shown in FIGS. 9 to 11, the locking mechanism 7 of the present embodiment includes a fluid bag 73 provided on the backrest 2, an actuator 75 communicating with the fluid bag 73 via a pipe 74, and an actuator 75. The locking member 76 driven by the above and the locking claw 77 provided on the rear end side of the gas spring 31 are used as elements. The locking member 76 is pivotally supported by the back support rod 21 so as to be able to rotate about the rotation center C of the backrest 2 and a substantially concentric axis, and has a partial arc shape similar to the contact portion in a side view. Form. The locking member 76 extends in a direction away from the fulcrum C, and has a plurality of steps of recessed grooves 761 formed on the surface facing the locking claw 77. The groove 761 can be selectively engaged.

  When the seated person is not leaning on the backrest 2, the backrest 2 is in the upright position, the fluid bag 73 is not receiving a load, and the locking member 76 is separated from the locking claw 77. FIG. 9 shows this state, and the gas spring 31 is allowed to move freely with respect to the locking member 76 through expansion and contraction of the cylinder 51. Therefore, the distance between the action point F and the fulcrum C is variable according to the weight of the seated person. When the seated person leans on the backrest 2, the fluid bag 73 that receives the load contracts and discharges the fluid, and the actuator 75 is driven by the fluid pressure to displace the locking member 76 forward. Then, the locking claw 77 engages with the concave groove 761 at any step in the locking member 76. FIG. 10 shows this state, and the gas spring 31 is prohibited from freely moving with respect to the locking member 76. Therefore, the distance between the action point F and the fulcrum C remains unchanged. If the seater further applies a load to the backrest 2 from the state of FIG. 10, the backrest 2 tilts from the standing position while maintaining the engagement between the locking claw 77 and the concave groove 761. Conversely, if the seated person stops drowning on the backrest 2 and the back is lifted from the backrest 2, the backrest 2 returns to the standing position and the fluid bag 73 expands and sucks the fluid. As shown in FIG. 9, the driven locking member 76 is retracted rearward, and the engagement between the locking claw 77 and the groove 761 is released. Incidentally, it is preferable to provide an elastic member for pushing back the locking member 76 in a direction away from the locking claw 77, for example, a winding spring (not shown) in the vicinity of the rotation center of the locking member 76.

  <Fourth Embodiment> The embodiment shown in FIG. 12 is a modification of the second embodiment, and a locking mechanism 7 is interposed between the front end side (or lower end side) of the gas spring 31 and the backrest 2. is doing. Specifically, the back support rod 21 extends rearward and upward from the fulcrum C toward the backrest surface, and the locking member 78 is provided at a location slightly deviated rearward from the fulcrum C. Unlike the second embodiment, in this embodiment, the locking member 78 is supported on the main body side of the chair.

  The gas spring 31 is pivotally attached to an intermediate portion of the back support rod 21 on the rear end side (upper end side). The front end side (lower end side) of the gas spring 31 is rotated back and forth (up and down) by the movement of the piston of the cylinder 51. Between the back support rod 21 and the gas spring 31, an auxiliary elastic member for assisting the return of the gas spring 31 and the action point F to the original position, for example, a winding spring (not shown) near the rotation center of the gas spring 31. Z).

  When the backrest 2 is tilted backward, the locking shaft 79 on the front end side engages with a concave groove 781 at any step formed in the locking member 78, and gas is generated between the locking member 78 and the back support rod 21. The spring 31 is compressed and exhibits a reaction force.

  In addition, in this embodiment, an elastic member 35 that applies a reaction force to the backrest 2 is also provided separately from the gas spring 31. The elastic member 35 is a coil spring with a manual reaction force adjustment mechanism, for example, as in a known office chair.

  According to each embodiment, the seat 1, the backrest 2 that can tilt with respect to the seat 1, the reaction force mechanism 3 that applies a reaction force to the backrest 2 when the backrest 2 tilts, A backrest in which the reaction force mechanism 3 tilts in response to a fluid pump 4 disposed under the seating surface of the seat 1 and a fluid pressure flowing out of the fluid pump 4 that receives a load of a seated person via the seat 1. Since the chair is provided with the reaction force adjusting mechanism 5 that varies the magnitude of the reaction force exerted on 2, the automatic adjustment function of the reaction force when the backrest 2 is tilted can be easily realized.

  The fluid pump 4 is a fluid bag that deforms and discharges fluid under the load of the seated person, and the reaction force adjusting mechanism 5 is connected to the fluid bag 4 at one end and flows out under the load of the seated person. A pipe 52 through which the fluid passes, and an expansion / contraction device 51 connected to the other end of the pipe 52 to expand and contract under the pressure of the fluid. The reaction force mechanism 3 applies the reaction force applied to the backrest 2. Since the action point F is displaced, the mechanism is not unnecessarily complicated.

  In addition, when the backrest 2 is in the standing position, a variation in the distance between the action point F and the rotation center C of the backrest 2 is allowed, and when the backrest 2 tilts from the standing position, Since the locking mechanism 7 is provided to suppress the fluctuation of the distance between the backrest 2 and the rotation center C, the reaction force is adjusted to a suitable magnitude according to the size of the seated person's body. The reaction force does not increase or decrease unexpectedly when the backrest 2 is tilted.

  The present invention is not limited to the embodiment described in detail above.

  <Fifth Embodiment> In particular, for the reaction force adjusting mechanism 5, instead of displacing the reaction point F of the reaction force exerted on the backrest 2 by the reaction force mechanism 3, the support position of the reaction force mechanism 3 may be displaced. I do not care. For example, as shown in FIGS. 13 to 15, one end side of an elastic member 31 such as a gas spring which is an element of the reaction force mechanism 3 is rotatably attached to the lower end portion of the back support rod 21, and the other end side is attached. It is attached to the main body side of the chair, for example, the seat receiver 11 so as to be slidable along a substantially arc-shaped locus centering on one end side.

  The reaction force adjusting mechanism 5 of the present embodiment has a reaction force acting direction with respect to a line segment connecting the center C of the tilting of the backrest 2 and the reaction force acting point F, in other words, a stretching direction (elasticity) of the gas spring 31 or the like. The magnitude of the reaction force is varied by changing the angle A in the deformation direction and the direction in which the reaction force acts. When the seated person is seated 1, the fluid pump 4 that receives the load of the seated person contracts and discharges the fluid, and drives the piston of the fluid pressure cylinder 51. The piston protruding from the cylinder 51 moves the gas spring 31 or the like, and as a result, the angle A formed by the line segment and the expansion / contraction direction of the gas spring 31 or the like expands (approaches vertical). The fluid pressure discharged from the pump increases as the weight of the seated person increases, and the protruding amount of the piston, and thus the angle A, also increases as the weight of the seated person increases. The amount of deformation of the gas spring 31 when the backrest 2 is tilted by the same angle increases as the angle A increases (closer to the vertical). FIG. 14 shows a state where a seated person with a relatively light weight is seated, and FIG. 15 shows a state where a seated person with a relatively heavy weight is seated. Accordingly, the reaction force generated by the gas spring 31 when the backrest 2 is tilted by the same angle is also increased. In this way, the reaction force can be automatically adjusted according to the weight of the seated person. When the seated person stands, the contracted fluid pump 4 expands to suck in the fluid, the piston is immersed in the cylinder 51, and the gas spring 31 is returned to its original position. FIG. 13 shows this state.

  <Sixth Embodiment> Alternatively, it is also conceivable that the fluid pressure flowing out from the fluid pump 4 receiving the load of the seated person is directly applied to the backrest 2. For example, as shown in FIG. 16, the fluid pump 4 and the actuator 54 are connected via a pipe 55, and the pressure discharged from the fluid pump 4 is supplied to the actuator 54. The actuator 54 is connected to the lower end of the back support rod 21 so that the fluid pressure flowing into the actuator 54 acts on the backrest 2 as a reaction force. In this example, an elastic member 36 is separately provided as the reaction force mechanism 3. In addition, the actuator 54 functions as an automatic reaction force adjusting mechanism 5 that adjusts the reaction force that pushes back the backrest 2 in the upright direction. While the manual reaction force adjustment mechanism attached to the elastic member 36 enables the reaction force adjustment according to the seated person's preference, the automatic reaction force adjusting mechanism 5 is automatically operated according to the weight of the seated person. The reaction force is finely adjusted.

  Further, when the elastic member of the reaction force mechanism is a gas spring, a coil spring or the like, the reaction force adjustment mechanism displaces the position of the spring retainer at the end of the gas spring or the like along the expansion / contraction direction. It is also conceivable to change the initial contraction amount, that is, the preload force.

  Other specific configurations of each part can be variously modified without departing from the spirit of the present invention.

The principal part side view which made the chair of one Embodiment of this invention typical. The principal part side view. The principal part side view. The side view which showed typically the chair of one Embodiment of this invention. The principal part side view. FIG. The side view which showed typically the chair of one Embodiment of this invention. The principal part side view. FIG. The principal part side view. The principal part side view. The side view which showed typically the chair of one Embodiment of this invention. The principal part side view which made the chair of one Embodiment of this invention typical. The principal part side view. The principal part side view. The principal part side view which made the chair of one Embodiment of this invention typical.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Seat 2 ... Backrest 3 ... Reaction force mechanism 4 ... Fluid pump 5 ... Reaction force adjustment mechanism 7 ... Locking mechanism

Claims (7)

Zodiac,
A backrest tiltable with respect to the seat;
A reaction force mechanism that applies a reaction force to the backrest when the backrest tilts;
A fluid pump disposed under the seating surface of the seat;
A chair provided with a reaction force adjusting mechanism that varies the magnitude of the reaction force that pushes back the tilted backrest in a standing direction according to the fluid pressure flowing out from the fluid pump that receives the load of the seated person via the seat. . The fluid pump is a fluid bag that deforms under the load of a seated person and discharges fluid,
The reaction force adjusting mechanism includes a pipe through which one end is connected to the fluid bag and receives a load of a seated person, and a telescopic device that is connected to the other end of the pipe and expands and contracts by receiving the pressure of the fluid. The chair according to claim 1, comprising: The chair according to claim 1 or 2, wherein the degree of change in the magnitude of the reaction force corresponding to the degree of tilting of the backrest is automatically set according to the load of the seated person. The chair according to claim 1, 2 or 3, wherein the reaction force adjusting mechanism displaces an action point of a reaction force applied to the backrest by the reaction force mechanism using the fluid pressure. The said reaction force mechanism has an elastic member which produces a reaction force, The distance between the said action point and the rotation center of the said backrest is fluctuate | varied by moving the elastic member using the said fluid pressure. The listed chair. Allow variation in the distance between the action point and the center of rotation of the backrest when the backrest is in the standing position, and the distance between the action point and the center of rotation of the backrest when the backrest tilts from the standing position. The chair according to claim 4 or 5, wherein a locking mechanism for suppressing the fluctuation is interposed between the elastic member and the backrest. The chair according to claim 1, 2 or 3, wherein the reaction force adjusting mechanism displaces a support position for supporting the reaction force mechanism using the fluid pressure.

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