The present invention relates to a chair suitably used at office and the like.
A chair which changes the direction and the angle of the backrest in accordance with the change of a seated person's posture, has conventionally existed. (for example, Patent Document 1 to 5)
A chair described in Patent Document No.1 is configured such that a pair of back plates is each attached to a frame through rubber parts, moves rotationally upward and downward and turns leftward and rightward while compressing the rubber parts and storing repulsion.
A chair described in Patent Document 2 is configured such that an upper half of the back of automobile sheet turns around the vertical axis while storing repulsion.
A chair described in Patent Document 3 is configured such that a back and a seat are integrally provided, a lower part of the seat is rollably supported around a fulcrum, and when rolling, the back and the seat compress rubber parts disposed around the lower part of the seat, and the repulsion that the back and the seat return to the reference position, is produced.
In a chair described in Patent Document 4, a back and a seat are integrally provided. A configuration is enclosed that a part of the back is fixed at fulcrum, and centering around this fulcrum, the back and the seat deform in such a way as to twist leftward and rightward in a front view with the elasticity of the back and the seat in accordance with the movement of a seated person.
A chair described in Patent Document 5 is configured such that a back and a seat are separated into a plurality of compartments, a part of the back and the seat among the components is partially separated so as to be partially easily deformed, accordingly the area between the compartments is easily twisted and the degree of deformation is increased.
Patent Document 1: Japanese Utility Model Registration No. 3135597
Patent Document 2: Japanese Patent No.3555175
Patent Document 3: US Patent Publication No. 2016-0081483
Patent Document 4: US Patent Publication No. 2015-0265052
Patent Document 5: EP Patent No.1401306
By the way, keeping the same posture on a seat for a long time is painful and a user continues to sit on a chair while changing the posture unconsciously. For this change of the posture, in order to change the rate of left-right load to prevent the pressure to gluteal region or femoral region, it is natural that twisting operation of the body is performed so that one of right and left of lower body, especially, gluteal region moves up, and the other moves down, while upper body moves in the opposite direction with keeping balance. Seen from the front side, left-right turning operation of a back is performed.
However, the chairs described in Patent Documents 1 and 2 just perform a rotating operation around vertical shaft. Therefore, the movement of a back does not match the above-described movement of the seated person and it is difficult to appropriately support the seated person.
Meanwhile, in the chair described in Patent Document 3, a back and a seat perform a turning operation, however, the back and the seat greatly incline in the same direction and this gives an imbalance to a seated person and it is also difficult for the seated person to rebalance.
Furthermore, in the chair described in Patent Document 4, the back performs a rotating operation so as to twist around a fulcrum and at the same time, the seat deforms. Therefore, when considering the movement of lower body and the movement of upper body, it cannot be said that the movement of the back and the seat matches the movement of the back of the seated person.
Further, in the chair described in Patent Document 5, the degree of deformation freedom is high, and on the other hand, a repulsion force to return to the original position easily becomes insufficient and supporting force becomes poor.
Especially, in view of various movement of the seated person, when pursuing provision of a non-conventional front, rear, left and right swinging operation to the seat, it is required that the back performs a new movement suitable for the left-right movement of the seat.
The present invention focuses on these problems, and in view of various movement of the seated person, in order to provide the left-right swinging operation to the seat in non-conventional aspect, an object thereof is to realize a chair wherein a back is capable of performing a new movement suitable for the left-right movement of the seat and returning to the predetermined position when the seated person leaves a seat.
The present invention adopts the following means to achieve such object.
That is, a chair according to the present invention, wherein the chair is configured such that a back is arranged behind a seat, and the back has an operation mechanism turning-movably supporting the load received from a seated person in a left-right direction in a front view, and when the load is applied, at least a part of guide part of the operation mechanism is separated and the back moves freely, and when the applied load is removed, the back automatically returns to the neutral position along the guide part.
With the configuration described above, the back is turning-movable in a front view in a left-right direction, and when the load is applied, at least a part of guide parts of the operation mechanism is separated, and the back moves freely. Therefore, it can be easily adapted to various movement of the seated person. Further, when the seated person leaves a seat, the back reliably returns to the neutral position along guide parts. Therefore, even if the degree of freedom of back movement is increased, a plurality of chairs is easily uniform in appearance when the seated person leaves a seat. Further, it is possible to avoid the situation in that the initial condition of the chair is changed every time the seated person sits on the seat.
When considering the load balance to a turning direction, it is desirable that the chair is configured such that a reaction force with which the back returns to the neutral position becomes larger in accordance with an amount of turning movement to both of the left and right directions.
To easily incorporate the operation mechanism, it is desirable that the back is configured such that a backrest is supported by a back frame via the operation mechanism, the back frame is erected at the rear of the seat, and the backrest is turning-movably attached to the back frame substantially clockwise or counterclockwise direction in a front view via the operation mechanism.
To realize an appropriate supporting force and returning force, it is desirable that the back is configured such that a backrest is supported by the back frame via the operation mechanism, and the backrest moves via the operation mechanism having an elastic body toward the rear direction and the turning direction against an elastic reaction force.
To realize a support which matches the body movement of the seated person, it is desirable that the backrest is configured such that a turning range to the left-right direction becomes larger in accordance with the movement in the rear direction with respect to the back frame.
To realize an appropriate supporting condition corresponding to the seated person's posture, it is desirable that the chair is configured such that the seat is swingable in the left-right direction in a front view, and the back performs a left-right turning operation separated from the seat.
To incorporate as operation unit for various purposes, it is desirable that the operation mechanism is provided with a base part and a tilting part, and includes a reference position, a guide part set at the side of the base part and a guide part set at the side of the tilting part are in pressure contact with each other to be guided by the shapes of the guide parts and stopped at the reference position, and when the pressure contact is loosened by the received pressure from the seated person, the base part and the tilting part can be relatively changed from the reference position in accordance with the degree of the received pressure.
To support the load of backrest and return to the reference position in an appropriate manner, it is desirable that the chair is configured such that the pressure contact of the both guide parts is formed by the elastic body and the elastic body is pressed by the received pressure, whereby the guide part of the tilting part and the guide part of the base part are separated.
To facilitate assembly, it is desirable that the operation mechanism includes: the base part fixed to the backrest and provided with the elastic body on the back surface side of the base part; the tilting part disposed at a position adjacent to the base part and including a guide part recessed in a tapered shape at the back surface side of the tilting part, the bottom part of the guide part having an opening; and a pressing tool including a guide part having a convex shape corresponding to the guide part of the tilting part on the front surface side of the pressing tool, the pressing tool being fixed to the base part via the opening of the tilting part in a state where the guide part of the pressing tool is fitted into the guide part of the tilting part, and the tilting part is fixed to the received pressure part provided at the upper end part of the back frame.
To increase a positioning function at the reference position, it is desirable that one guide part has a substantially partially elliptical mortar-like shape including at least one valley line and the other guide part has a curved shape having at least one ridge line fitted smoothly into the valley line, and the valley line and the ridge line can be fitted into each other.
As the other configuration to easily realize the operation mechanism, one guide part of the both guides are a shaft-shaped part extended upward and downward, or leftward and rightward and the other guide part is a V-groove leading the upper-lower or left-right shaft-shaped member to the center position.
To prevent concentration of the local load in the guide part, it is desirable that the base part and the tilting part are provided with engaging parts configured to regulate a relative movement of the base part and the tilting part in collaboration with the guide parts.
To effectively correspond to behavior of the back that the upper edge of the backrest moves backward or backward and the lower edge of the backrest moves forward or backward, it is desirable that one guide part has three protrusion parts and the other part is in a shape which receives the three protrusion parts, and an elastic body is placed between the one guide part and the other guide part.
According to the present invention, in view of various movement of a seated person, when giving the left-right swinging operation to the seat in the non- conventional aspect, it is possible to provide a new chair wherein the back can perform a new movement suitable for the left-right movement of the seat and return to the predetermined position when the seated person leaves a seat.
An embodiment of the present invention will be described below with reference to the drawings.
As illustrated in
The support base part 2 functions as a structured body for receiving the load applied by seated person, and in the support base part 2, a left-right pair of arm attachment parts 23 is integrally formed with the support base part 2 via a bearing base part 22 on both left and right sides of a support base main body 21 including a through hole 21a along an up-down direction into which an upper end of the supporting post 13 is inserted. A shaft swing damper 21b is attached to the hole 21a opening on the surface of the support base main body 21 in the front-rear direction and upper ends of left-right swing links L1, L2 are attached to holes 22a opening on the front and rear surfaces of the bearing base part 22, via swing support shafts S1, S2.
The left-right swing part 4 includes a pair of plate-shaped link bases 41 disposed separated from each other in the front-rear direction to perform a swinging operation in the left-right direction with respect to the support base part 2, and a left-right swing main body 42 configured to connect the pair of link bases 41, 41. At both left and right ends of the link bases 41, holes 41a, 41a are opened and the lower ends of the left-right swing links L1, L2 are attached via swing shafts S3, S4.
That is, as illustrated in
A window 41c is opened at the center of the link base 41, a rolling damper 44 is positioned in the window 41c, and a swing range of the left-right swing part 4 is restricted to a range where the rolling damper 44 can perform a relative movement within the window 41c.
The front-rear swing part 3 includes a pair of plate-shaped rail plates 31, 31 disposed separated from each other in the left-right direction to perform a swinging operation in the front-rear direction with respect to the left-right swing part 4, and an upper connection plate 32 and a front connection plate 33 configured to connect the pair of rail plates 31, 31. At a front side of the rail plates 31, a guide hole 34 is provided to penetrate the rail plates 31, a bearing 45a is engaged in the guide hole 34, and the bearing 45a is a rolling body 45 provided to be rollable independently to the left and right on a side surface at a front end side of the left-right swing main body 42. The reference sign 45z in the drawings indicates a spacer disposed on an inner surface side of the rail plate 31 and having a diameter larger than that of the bearing 45a. The rear end side of the rail plate 31 extends rearward and downward, a lower end of a link arm LA, being a swingable front-rear swing link, is attached via a swing shaft S5 to an extension end of the rail plate 31, and the upper end of the link arm LA is supported by the rear end of the left-right swing body 4 via a swing shaft S6. That is, the rear end of the front-rear swing part 3 is disposed in a suspended state to be swingable forward and rearward with respect to the left-right swing part 4 via the link arm LA. The guide hole 34 has a shape that is gently curved forward and downward from the rear end side toward the front end side, and at the rear end, there is provided a shockless part SL configured to mitigate a shock when the front-rear swing part 3 moves forward together with the seat 5. The upper connection plate 32 is provided with a unit attached hole 32a penetrating in the up-down direction, and a front-rear lock unit 8 described later based on
That is, if the front-rear swing part 3 moves rearward, as illustrated in
On the front end side of the rail plate 31 included in the front-rear swing part 3, a pitching damper 31c formed by bending a part of the rail plate 31 is provided, and when swinging rearward, the front-rear swing part 3 abuts against a front end lower part 4z (see
As illustrated in
A front-rear stopper mechanism 8M utilizing the front-rear lock unit 8 illustrated in
In this embodiment, the left-right swing part 4 is supported by the support base part 2 and the front-rear swing part 3 is supported by the left-right swing part 4 so that a layered structure is formed in which the left-right stopper mechanism 7M is provided between the support base part 2 and the left-right swing part 4, and the front-rear stopper mechanism 8M is provided between the left-right swing part 4 and the front-rear swing part 3.
The left-right stopper mechanism 7M is configured to switch between allowing and suppressing the swinging of the seat 5 in the left-right direction, by engaging or disengaging an engaging part 71 and an engaged part 72 illustrated in
As illustrated in
When the casing 70 is fitted into the unit attached hole 42a of a swing main body part 42 included in the left-right swing part 4 illustrated in
As illustrated in
The front-rear stopper mechanism 8M is configured to switch between allowing and suppressing the swinging of the seat 5 in the front-rear direction, by engaging or disengaging an engaging element 81 and an engaged part 82 illustrated in
The casing 80 has a flat saucer-shape opened upward, and thus, the engagement pin 81a is guided by a guide 80g1 in the casing 80, and is disposed to be liftable and lowerable with a part of the engagement pin 81a protruding from a lower end of the casing 80. The conversion mechanism 84 includes the above-described coil spring 83a provided elastically in a compressed state between an upper end of the engagement pin 81a and a cover 80a closing the upper opening of the casing 80, a stopper operation arm 85 rotatably supported by a horizontal shaft 80c disposed between side walls 80b, 80b of the casing 80 at a position adjacent to the engagement pin 81a, a torsion coil spring 86 rotatably attached together with the stopper operation arm 85, and a wire tube 87 having a spherical wire tip end 87a that is attached to the stopper operation arm 85 and a tube tip end 87b locked to the casing 80. As illustrated in
When the operation lever 152a illustrated in
It is noted that, in the chair according to the embodiment, a control mechanism 8X configured to automatically suppress a movement of the seat 5 in the front-rear direction at a predetermined position when the seated person leaves the seat, is provided along with the half-piece of an unit 8 of the front-rear stopper mechanism 8M.
First, to detect seating of the seated person, a configuration is such that a weight-receiving part 50 (see
The operation changer 8X changes the allowed/suppressed states of the operation of the front-rear swing part 3 when an engagement state of an engaging part 81X illustrated in
The chair is configured such that the engaged part 82X is a recess 82aX, and when the load applied by seated person is received in the state where the engaging part 81X is fitted into the recess 82aX, the fitted state is released, so that the engaging part 81X and the engaged part 82X are disengaged due to the load applied by seated person, and when the load applied by seated person is removed, the engaging part 81X and the engaged part 82X engage with each other by the elastic force to bring the front-rear swing part 3 into an operation-suppression state.
The control mechanism 8X includes an engagement pin 81aX being the engaging part 81X; and a groove-shaped recess 82aX being an engaged part 82X provided on a sliding surface 40X relatively operating at a position facing the engaging pin 81X. The engagement pin 81aX is configured to be elastically biased toward the sliding surface 40X, and to fit in the groove-shaped recess 82aX at a predetermined position. Then, when the seat 5 detects received of the load applied by seated person in a central part, the control mechanism 8X illustrated in
The engagement pin 81aX is disposed to be 1 liftable and lowerable along front, rear, right, and left guides 80g2 of the casing 80, in a parallel relationship with the engagement pin 81 in the flat casing 80 configuring the front-rear stopper mechanism 8M. Similarly in parts to the conversion mechanism 84, the conversion mechanism 84X includes the coil spring 83aX provided elastically in a compressed state between an upper end of the engagement pin 81aX and the cover 80a closing the upper opening of the casing 80, a safety operation arm 85X rotatably supported by the horizontal shaft 80c disposed between side walls 80b, 80b of the casing 80 at a position adjacent to the engagement pin 81aX, and a torsion coil spring 86X rotatably attached together with the safety operation arm 85X. On the other hand, the weight-receiving part 50 is, as illustrated in
As illustrated in
That is, when a user is seated, the control mechanism 8X is unlocked, and afterwards, whether or not the seated person locks a movement in the front-rear direction depends on the state of a front-rear fixing stopper mechanism 8M, via the operation of the operating member 152, and when the seated person leaves the seat, the state is maintained unless the front-rear fixing stopper mechanism 8M is unlocked, and if the front-rear fixing stopper mechanism 8M is unlocked, the control mechanism 8X actuates to lock the front-rear operation of the seat 5.
In particular, in this chair, the seat 5 tilts at least back and forth, and when the seated person starts standing up, the seat 5 moves while tilting forward together with the front-rear swing part 3, as illustrated in
It is noted that, when a person sits on the seat, the engagement pin 81aX and the recess 82aX are disengaged, however, the engagement pin 81aX and the recess 82aX engage with a certain degree of resistance, and thus, the locked state is not released immediately after the person sits on the seat, but is released when the resistance decreases due to a small movement of the seat 5.
That is, the control mechanism 8X switches the locked state of the seat 5 between when the seated person leaves the seat and when sitting on the seat, and thus, may be called a “seat-leaving and seat-sitting automatic stopper mechanism”.
Next, the guide hole 34 illustrated in
Therefore, in the present embodiment, as illustrated in
A lateral dimension wl of the guide surface 31b1 is greater than a thickness t1 of the rail plate 31 being the plate member PM. The guide surface 31b1 is integrally formed of metal together with the rail plate 31. As illustrated in
The flange part 31b according to this embodiment is configured by plastic deformation processing of the plate member PM around the guide hole 34, and specifically, by adopting burring processing. In general, in the burring processing, a pilot hole is opened in a plate member, the periphery of the pilot hole is fixed with a jig and in this state, the edge of the pilot hole is raised, by pressing with a tool larger than the pilot hole, to form a flange part, and thus, a cylindrical flange is generally formed. So far, burring processing has only been utilized for forming tapped holes and the like and has not been considered for producing a structure for guiding a rolling body.
Therefore, in the present embodiment, based on this new perspective, as illustrated in
The manufacturing means for the guide hole 34 is selected based on the conditions that the guide surface 31b1 is smooth, the guide surface 31b1 has strength, and the manufacturing cost is low. Fine blanking processing and other processing were also tried, however, it turned out that, even though the fine blanking processing relatively likely to be selected was excellent in forming a smooth guide surface, the plate member needed to have a considerable thickness to obtain strength. Thus, the fine blanking processing could not be adopted due to its inappropriate cost and other processing also did not satisfy the conditions above. Overall, it turned out that burring processing met these conditions very suitably.
However, when a shortest distance D from the guide hole 34 to the nearest edge of the plate member PM is narrow in the burring processing, the plate member PM is deformed during the processing or due to the load applied during the processing. As a result of attempting various tests in this embodiment, it was found that it was necessary and sufficient, as a condition for obtaining a stable shape, to set the shortest distance D (see
As illustrated in
Further, when a left-right support state of the front-rear swing part 3 for the left-right swing part 4 becomes unbalanced, a lower region of the guide hole 34 causes the bearing 45a being the rolling body 45 to abut against the lower region of the guide hole 34 to support the bearing 45a and the flange part 31b contributes to supporting the load during this time.
Generally speaking, as illustrated in
As described above, the guide hole 34 is formed in the vertical surface of the movable portion or the support portion of the chair and moves while receiving the load applied by seated person. The movable portion is supported at two locations on the front and rear side by the support portion including a guide structure configured by the rolling body 45 and the guide hole 34. In the present embodiment, the other movable portion of the chair is supported by the link arm LA, any one of the front and rear support structures is configured by the above-described rolling body 45 and the guide surface 31b1, and the other is configured by a different support structure, that is, in this embodiment, of the link structure.
Next, the support mechanism of the back 6 will be described. As illustrated in
The backrest 62 includes a cushion arranged on the front surface of a back plate 62a and the backrest 62 is entirely covered by an upholstery fabric. A lower end of the backrest 62 is disposed at a predetermined distance above the seat surface and the backrest 62 is supported on a back surface side by a back support part 61a at an upper end of the back frame 61 via the operating mechanism 6M.
The operating mechanism 6M includes: a base part 64 fixed to or formed integrally with the back plate 62a included in the backrest 62 and including an elastic member 65 arranged on a back surface side of the base part 64; a tilting part 65 disposed at a position adjacent to the base part 64 and including a guide part 65a recessed in a tapered shape at the back surface side, the center of the guide part 65a being open in the front-rear direction; and a pressing tool 66 including a guide part 66a having a convex shape corresponding to the guide part 65a of the tilting part on the front surface side of the pressing tool, the pressing tool 66 being fixed to the base part 64 via the opening of the tilting part 65 in a state where the guide part 66a of the pressing tool is fitted into the guide part 65a, as illustrated by an arrow J in
More specifically, as illustrated in
In this embodiment, urethane is used for the elastic body 67, and as illustrated in
That is, the backrest 62 is disposed in a positional relationship where the backrest 62 moves against the elastic reaction force in the rearward direction and the turning direction while being supported by the elastic body 67, and a configuration is such that, when the elastic body 67 is deformed to the front, rear, right, or left in accordance with the amount of turning movement in the front, rear, right, or left directions, the reaction force returning the backrest 62 to a neutral position increases. The turning direction includes a turning movement in the left-right direction in front view, as illustrated in
The guide part 65a of the tilting part 65 and the guide part 66a of the pressing tool 66 included in the base part 64 are guided to, and a shape of the guide parts 66a, 65a are in pressure contact with each other to be guided by the elastic body 67 and stands still to the reference position illustrated in
It is noted that, as illustrated in
As described above, the left-right turning operation of the back 6 occurs with respect to the back frame 61 and the seat 5 is attached to the front-rear swing part 3 to which the back frame 61 is attached, and thus, the back frame 61 and the seat 5 integrally swing in the left-right direction in front view, however, the backrest 62 further performs a different movement separately from the left-right turning operation of the seat 5 and the back frame 61.
It is noted that, in this embodiment, the base part 64 is attached to the backrest 62 and the tilting part 65 is attached to the side of the back frame 61, however, a configuration may be so that the base part 64 is attached to the side of the back frame 61 and the tilting part 65 is attached to the side of the backrest 62.
Next, a front support mechanism of the seat will be described.
As described above, in this chair, the seat 5 is configured to be supported to be swingable to the front, rear, right, or left with respect to the support base part 2, however, a feeling of pressure on a femoral region of the left and right legs of the seated person sitting on the chair configured to swing to front, rear, right, or left, may change to be unbalanced depending on the posture of the seated person. Further, in this chair, the back 6 is provided to tilt rearward behind the seat 5 and when the back 6 tilts rearward, the seat 5 moves together with the back 6 and performs an operation in which the front part of the seat 5 rises relative to the back part of the seat 5 which descends, and as a result, the seated person may experience a feeling of pressure on the femoral region of the legs when leaning rearward and anxiety or instability due to the legs of the seated person being lifted in the air.
Thus, as illustrated in
The deformation part 5X is provided at a position receiving the weight of the legs of the seated person, and is configured to deform downward when receiving the weight of the legs and to return upward when the weight of the legs is removed.
Specifically, as illustrated in
Then, the seat outer shell 51 is fixed to the front-rear swing part 3, and the rear part 53a of the seat inner shell 53 is attached above the seat outer shell 51. Thus, the deformation part 5x including the front part 53b of the seat inner shell 53 is deformed toward the seat outer shell 51.
In this embodiment, a front seat lower cover 55 is attached to the front part 53b forming the deformation part 5X of the seat inner shell 53, with the seat outer shell 51 interposed therebetween. Although
At two locations on the left and right of the front part of the seat outer shell 51, compression springs 56 being elastic bodies are arranged at positions compressed between the front part 53b of the seat inner shell 53 and the front part of the seat outer shell 51.
When the deformation part 5X at the side of the seat inner shell 53 approaches the seat outer shell 51, as illustrated in
Here, as illustrated in
It is noted that, in the chair according to the present embodiment, as illustrated in
As described above, the chair according to the present embodiment is configured such that the back 6 is arranged behind the seat 5, and the back 6 has an operation mechanism 6M turning-movable supporting the load received from a seated person in left-right direction in a front view, and when the load is applied, at least a part of guide parts 65a, 66a of the operation mechanism 6M is separated, and the back 6 moves freely, and when the applied load is removed, the back 6 automatically returns to the neutral position along the guide parts 65a, 66a.
Therefore, the back 6 is turning-movable in a front view in a left-right direction, and when the load is applied, at least a part of guide parts 65a, 66a of the operation mechanism 6M is separated, and the back 6 moves freely. Therefore, it can be easily adapted to various movement of the seated person. Further, when the seated person leaves a seat, the back 6 reliably returns to the neutral position along guide parts 65a, 66a. Therefore, even if the degree of freedom of back 6 movement is increased, a plurality of chairs is easily uniform in appearance when the seated person leaves a seat. Further, it is possible to avoid the situation in that the initial condition of the chair differs every time the seated person sits on the seat.
Further, the chair is configured such that a reaction force with which the back 6 returns to the neutral position becomes larger in accordance with an amount of turning movement to both of the left and right directions. Therefore, the load in turning direction is easily balanced and an appropriate reaction force in accordance with the seated person's posture is easily obtained.
Further, the back 6 is configured such that a backrest 62 is supported by a back frame 61 via the operation mechanism 6M, the back frame 61 is erected at the rear of the seat 5, and the backrest 62 is turning movably attached to the back frame 61 substantially clockwise or counterclockwise direction in a front view via the operation mechanism 6M. Therefore, the operation mechanism 6M is configured only by introducing a simple turning mechanism or loose convex-concave structure in a part of the backrest 62.
Further, the back 6 is configured such that the backrest 62 is supported by the back frame 61 via the operation mechanism 6M, and the backrest 62 moves via the operation mechanism 6M having an elastic body 67 toward the rear direction and the turning direction against an elastic reaction force. Therefore, supporting force and returning force in accordance with size of displacement can be provided by moving the backrest 62 against the elastic reaction force of the elastic body 67.
Further, the backrest 62 is configured such that a turning range to left-right direction becomes larger in accordance with the movement in the rear direction with respect to the back frame 61, and the turning operation of the seated person to left-right direction becomes larger as the seated person deeply leans against the backrest 62. Therefore, it is possible to realize the support that matches body movement of the seated person.
Further, the seat 5 is swingable in the left-right direction in a front view, and the back 6 performs a left-right turning operation separated from the seat 5. Therefore, left-right swinging of the seat 5 and left-right turning operation of the backrest 62 work together through the seated person's posture. In consequence, it is possible to realize an appropriate support state in accordance with the seated person's posture.
Further, the operation mechanism 6M is provided with a base part 64 and a tilting part 65, and includes a reference position, a guide part 66a set at the side of the base part 64 and a guide part 65a set at the side of the tilting part 65 are in pressure contact with each other to be guided by the shapes of the guide parts 66a, 65a and stopped at the reference position, and when the pressure contact is loosened by the received pressure from the seated person, the base part 64 and the tilting part 65 can be relatively changed from the reference position in accordance with the degree of the received pressure. Therefore, while the operation mechanism 6M has a simple structure, the operation mechanism 6M has a function to return to the reference position when the applied load is removed, and can be incorporated as an operation unit for various intended use including the present embodiment.
Further, the chair is configured such that the pressure contact of the both guide parts 66a, 65a is formed by the elastic body 67 and the elastic body 67 is pressed by the received pressure, whereby the guide part 65a of the tilting part 65 and the guide part 66a of the base part 64 are separated. Therefore, the elastic body 67 can serve as a role to flexibly receive the load of the backrest and as a role to return the guide parts, 66a, 65a to the reference position.
Further, the operation mechanism 6M includes: the base part 64 fixed to the backrest 62 and provided with the elastic body 67 on the back surface side of the base part 64; the tilting part 65a disposed at a position adjacent to the base part 64 and including a guide part 65a recessed in a tapered shape at the back surface side of the tilting part, the bottom part of the guide part 65a having an opening; and a pressing tool 66 including a guide part 66a having a convex shape corresponding to the guide part 65a of the tilting part on the front surface side of the pressing tool, the pressing tool 66 being fixed to the base part 64 via the opening of the tilting part 65 in a state where the guide part 66a of the pressing tool is fitted into the guide part 65a of the tilting part, and the tilting part 65 is fixed to the back support part 61a provided at the upper end part of the back frame 61. Accordingly, a structure that allows an easy assembly can be realized.
Further, one guide part 65a has a substantially partially elliptical mortar-like shape including at least one valley line 65ax and the other guide part 66a has a curved shape having at least one ridge line 66ax fitted smoothly into the valley line 65ax, and the valley line 65ax and the ridge line 66ax can be fitted into each other. With the structure, the positioning function at the reference position can be enhanced.
Further, the base part 64 and the tilting part 65 are provided with engaging parts 64b,65b configured to regulate a relative movement of the base part 64 and the tilting part 65 in collaboration with the guide parts 66a,65a, and a part of the load of the backrest is supported by these engaging parts, 64b, 65b. Therefore, it is possible to prevent the local load from concentrating on the guide parts, 6a, 65a.
Although an embodiment of the present invention was explained above, the specific configuration of each part is not limited to those in the embodiment described above.
For example, the chair illustrated in FIG.41, 42 and 43 includes an operation mechanism 106M different from one of the above-described embodiments at the back to support turning-movably the load received from seated person in left-right direction in front view. The operation mechanism 106M is also configured such that when the load is applied, at least a part of guide parts, 165a, 166a of the operation mechanism is separated and the back moves freely, and when the applied load is removed, the operating position of the operation mechanism 160M automatically returns to the neutral position along the guide parts,165a, 166a of the operation mechanism 106M.
Specifically, the operation mechanism 106M is provided with a base part 164 and a tilting part 165, and includes a reference position, a guide part 166a set at the side of the base part 164 and a guide part 165a set at the side of the tilting part 165 are in pressure contact with each other to be guided by the shapes of the guide parts 166a, 165a, and stopped at the reference position, and when the pressure contact is loosened by the received pressure from the seated person, the base part 164 and tilting part 165 can be relatively changed from the reference position in accordance with the degree of the received pressure. This function is also the same as one of the above-described embodiment.
However, the shapes of the guide parts, 166a, 165a are different from those of the above-described embodiment. One guide part 166a is a shaft-shaped part 166 extended upward and downward, or leftward and rightward and the other guide part 165a is a V-groove leading the upper-lower or left-right shaft-shaped member 166 to the center position. A semicircle groove bottom 165a1 that defines the reference position at the center of the groove is formed. The tilting part 165 is freely movable in a gap between the base part 164 and the shaft shaped member 166. For the free movement, it is configured so as to be required to press an elastic body 167 interposed between the tilting part 265 and the base part 164 against the elastic force. In this case, the shaft-shaped member 166 is dividedly placed at the position avoiding the elastic body 167, and kept in the position by supporting members, 164b, 165b. With the configuration, the operation mechanism is simply realized.
Further, the V-groove is formed in a part of a window 164b1 being an engaging part and a part of the shaft-shaped part 166 being an engaging part is relatively-movable in the range controlled by the window 164b1. Therefore, it can be said that the base part 164 and the tilting part 165 are provided with the engaging parts configured to regulate the relative movement of the base part 164 and the tilting part 165 in collaboration with the guide parts, 165a, 166a. As a part of the load of the backrest is supported by the engaging part, it is possible to prevent the local load from concentrating on the guide part.
Then, even when this operation mechanism 106M is applied instead of the operation mechanism 6M described in the above-described embodiment, a configuration is realized that the back 6 is swingable in the left-right direction in a front view, and the back 6 performs a left-right turning operation separated from the seat 5.
The chair illustrated in
Then, the seat is swingable in the left-right direction in a front view, and the back 6 performs a left-right turning operation separated from the seat.
Specifically, the operation mechanism 206M is provided with a base part 264, a tilting part 265, and a back frame received pressure part 261a at the upper end side of a back frame 261, and. includes a reference position, a first guide part 266a1 set at the side of the base part 264 and a first guide part 265a1 set at the side of the tilting part 265 are in pressure contact with each other, and pressure contact of a second guide part 266a2 set at the side of the base part 264 and a second guide part 265a2 set at the side of the back frame received pressure part 261a are in pressure contact with each other to be guided by the shapes of the guide parts ,266a1, 265a1(266a1, 265a1) and stopped at the reference position, when the pressure contact is loosened by the received pressure from the seated person, the base part 264 is integrated with the pressing tool 266 in accordance with the degree of the received pressure and can be relatively changed from the reference position with respect to the tilting part 265 and the back frame received pressure part 261a.
The operation mechanism 206M includes: the base part 264 fixed to or formed integrally with the back plate included in the backrest, and provided with the pressing tool 266 at the side of the back surface in an a protruding condition; the tilting part 265 disposed at a position adjacent to the base part 264, including the first guide part 265a1 recessed in a tapered shape at the back surface side of the tilting part, the center of the tilting part 265 having an opening in front-rear direction; and the back frame received pressure part 261a placed at the position facing the tilting part 265 interposing the pressing tool 266 and having the second guide part 265a2 that is recessed in a tapered shape on the front surface side. The pressing tool 266 is provided with the first convex guide part 266a1 and the second convex guide part 266a2 corresponding to the first guide part 265a1 and the second guide part 265a2 on the front surface side or the back surface side. As shown by arrow J1 in the FIG.44, 45, the pressing tool 266 is fixed to the base part 264 through the opening of the tilting part 265, and the tilting part 265 is drawn and fixed by a screw to the back support part 261a at the upper end side of the back frame 261 configuring the back 206 as shown by arrow K1. At this time, the first elastic body 267a1 is interposed between the pressing tool 266 and the back frame received pressure part 261a, and the second elastic body 267a2 is interposed between the pressing tool 266 and the tilting part 265.
That is, the pressing tool 266 is fixed to the base part 264 in a state where the tilting part 265 is interposed between the pressing tool 266 and the base part 264, whereby, the pressing tool 266 is integrated with the base part 264 and configures a part of the base part 264. The pressing tool 266 is freely movable in a gap between the base part 264 and the back frame received part 261a. To freely move, the pressing tool 266 is configured such that it is required to compress the elastic body 267 interposed among the tilting part 265, the back frame received pressure part 261a and the pressing tool 266 against the elastic force. The force in the direction where the guide part 266a1 of the pressing tool 266 is constantly fitted into by the elastic body 267a1, is applied to the guide part 265a1 of the tilting part 265, and the force in the direction where the guide part 266a2 of the pressing tool 266 is constantly fitted into by the elastic body 267a2, is applied to the guide part 265a2 of the back frame received pressure part 261a.
Therefore, the first guide part 266a1 and the second guide part 266a2 of the pressing tool 266 are provided with three protruding parts resembling propeller blade, and the first guide part 265a1 at the side of the tilting part 265 and the second guide part 265a2 at the side of the back frame received pressure part 261a that receive& the protruding parts have a notch groove shape that receives a part of the three protruding parts. Specifically, the guide parts 266a1, 266a2 have a polygonal line part being a convex and the guide parts 265a1, 265a2 are in a notch shape having a valley line part.
When the seated person leans against a back 202, the first guide part 266a1 at the side of the base part 264 is separated from the first guide part 265a1 at the tilting side and the second guide part 266a2 at the side of the base part 264 is separated from the second guide part 265a2 at the side of the back frame received pressure part 261a while the pressing tool 266 at the side of the base part 264 presses the first, second elastic members 267a1, 267a2. Therefore, The base part 264 as well as the pressing part 266 can freely move, when the applied load is removed, the first elastic member 267a1, the second elastic member 267a2 press the pressing tool 266 to the tilting part 265 and the back frame received pressure part 261a, and the first guide part 266a1 engages with the second guide part 265a1 and second guide part 266a2 engages with the second guide part 265a2. Therefore, the back returns to the reference position.
That is, when the load of the backrest is applied to an upper half from the center of the operation mechanism 206M, the behavior arises that the upper edge of the backrest moves the rearward and the lower edge of the backrest moves the forward around the center of the operation mechanism 206M, and the applied load of the backrest is removed, a reverse operation is performed. Thus, it is an effective support structure for the behavior of the back 6 that the upper edge of the backrest moves rearward or forward and the lower edge of the backrest moves forward or rearward.
It is noted that an object illustrated as the reference sign 265x in the drawing is a protrusion for dividing and storing the elastic part 267. The protrusion 264z and the opening 265z illustrated in the drawings make up an engaging part that regulates the range of free movement of the base part 264.
With the above-described configuration, functions and effects according to the above-described embodiment can be obtained.
Various other changes may be applied to other configurations without departing from the spirit of the present invention.
Since the chair according to the present invention is configured as described above, the chair can be utilized especially suitably in an office and the like.
Filing Document | Filing Date | Country | Kind |
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PCT/JP2017/022760 | 6/20/2017 | WO | 00 |