JP4735966B2 - Back support device, seat support device and chair - Google Patents

Description

  The present invention relates to a chair suitably applied in an office or the like, and relates to a back support device, a seat support device, and a chair that provide a backup function adapted to the behavior of a worker.

For chairs used in offices, etc., taking into account long-time desk work, etc., to back up the body properly, the shape and angle of the back seat, refresh and rest so that the body during work is not burdened Various ingenuity has been devised, such as the tilt function and the locking function.

However, in offices, etc., you can rest by leaning on one elbow, etc., sitting in a simple manner with a worker on the side or diagonally behind while sitting, or moving documents or other items to the periphery, etc. There are many. In such a case, in the conventional chair made with emphasis on the movement in the front-rear direction, the back can often hinder the movement.

Although it is not a chair used in an office, it is possible to back up body movements necessary for rearward confirmation etc. in a car, as shown in Patent Document 1, considering the movement of the body different from the conventional one. The function of the car seat has been proposed. This seat is provided with a rotation shaft at a position that cuts the center in the width direction, and the upper half of the back that is provided independently of the lower half is rotated around this rotation shaft, so that the body can be twisted. It is a thing.
Japanese Utility Model Publication 4-34111

  However, such a seat function may be suitable as a backup for the operation of turning while holding the steering wheel, but is not necessarily appropriate as a function for backing up an operation performed in an office or the like. In offices and the like, when taking the above-mentioned sitting posture or performing an access operation to the surroundings, the operation as described in the above patent publication such as twisting the body around the spine without moving the spine is rather unnatural, Actually, it is accompanied by the behavior of twisting around the upper scapula of the body while moving the center of gravity slightly in the direction where it wants to rest and where it wants to access.

  Based on such knowledge, the present invention seeks to provide a new and useful chair that can be better adapted to the movement of a seated person in the office.

  In order to achieve this object, the present invention takes the following measures.

That is, the back support device of the present invention includes a backup surface formed on the back support rod side, and a movable surface attached to the backrest side so as to contact or be close to the backup surface and swingable with the backrest. In addition, at least one of the back-up surface or the movable surface is provided with a curved portion that gradually increases the opposing distance as it is displaced in the width direction from the center, so that the load applied to the backrest from the seated person is from the width direction center of the backrest to the width direction. When moving to the back-up surface, the movable surface is configured to be able to follow the left-right direction while rolling on the back-up surface. A flat surface or a curved surface having the same curvature is used.

That is, when the seated person is drooping in a normal posture, the back of the back is in contact with the center of the back in the width direction, and if the seated person twists the body in that state, the spine moves with its twisting motion. The natural movement is that the entire back rolls on the backrest while moving away from the center in the width direction. According to this embodiment, exactly the same movement as this can be given as the rolling motion of the movable surface with respect to the backup surface, and consequently the rolling motion of the backrest with respect to the back support rod. In addition, since the portion extending from the center of the backup surface and the movable surface to the constant region in the width direction is formed on a flat surface parallel to each other or a curved surface having the same curvature, the seated person usually sits back while sitting. Even if the center of the load moves in the width direction in small increments, it is possible to prevent the backrest from reacting one by one and ensure a stable seating state.

As a preferred backrest configuration, the lower part of the backrest is fixed to the back support side at least in the front-rear direction, the upper part is released, and the backrest is free from the uneven load in the width direction applied to the backrest from the seated person. An example is one in which the upper part of the backrest can be twisted and deformed downward using elasticity.

  In order to appropriately regulate the movable range of the movable surface, a predetermined gap is formed between the movable surface and a regulating surface that accommodates the backup surface in a relative swingable manner in the gap is integrated with the movable surface. It is preferable that the swinging end of the movable surface be in contact with the backup surface at the swinging end of the movable surface to restrict further swinging of the movable surface.

  In order to prevent the user from feeling uncomfortable at the time of taking off and seating, a predetermined space is formed between the movable surface and a regulating surface for accommodating the backup surface in a relative swingable manner is provided integrally with the movable surface. It is desirable that an urging means for pressing the movable surface against the backup surface is interposed between the backup surface and the regulating surface.

  Since the present invention has the configuration described above, the backrest is not obstructed even if a behavior such as twisting around the upper scapula is performed while slightly moving the center of gravity in the direction in which the seated person wants to rest or access. Thus, it is possible to provide a new and useful back support device that can follow the above and maintain an appropriate backup state.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

The chair of the present embodiment shown in FIGS. 1 and 2 supports a backrest 3 on a back support 1 via a back support device 2, and the back support device 2 is a seated person seated on a seat 8. The backrest 3 is provided with a function of supporting the backrest 3 so as to be movable in the same direction in order to adapt to the twisting operation to the side or obliquely rearward and the tilting operation to the side. In addition, this chair includes a lumbar support 4, and the lumbar support 4 can be directly adjusted to a desired protrusion amount and height position through a simple structure and operation.

  More specifically, the back support rods 1 are rearward and upwardly projecting in pairs, and a backup member 12 is horizontally mounted on the projecting end via a bracket 11, which is shown in FIG. As shown in the figure, a curved plate 12y having a predetermined curvature is formed by plastic deformation processing in a region reaching the left and right end portions adjacent to the central flat portion 12x and having a front surface as a backup surface 12a. Yes. Further, a bearing member 14 shown in FIGS. 2 and 4 and the like is attached to the back support rod 1 in the vicinity of the lumbar portion corresponding to the lumbar spine 1 via a bracket 13. The bearing member 14 has a standing wall 141 having a long hole 141 a extending in a substantially vertical direction, and the standing wall 141 is positioned at a portion facing the lower side edge of the backrest 3.

  On the other hand, as shown in FIGS. 1 and 2, the backrest 3 has a cushion material (not shown) attached to the front side of a relatively hard resin-made backrest inner shell 31 having elasticity, and is stretched from above. The ground 33 is covered up to the portion extending over the back surface, and when the backrest inner shell 31 is formed, the movable member 34 shown in FIGS. 3 and 5 is integrally formed in the corresponding portion of the backup member 12. The movable member 34 has a plate shape with a rear surface as a movable surface 34a, and a curved portion 34y having a predetermined curvature larger than that of the backup surface 12a is formed in a region reaching the left and right ends adjacent to the central flat portion 34x. is doing. And this movable surface 34a is arrange | positioned in the position which faces the said backup surface 12a. That is, the facing distance d between the backup surface 12a and the movable surface 34a is set so as to gradually widen as the curved portions 12y and 34y are displaced in the width direction from the center, and the both surfaces 12a and 34a are joined. In this state, the movable surface 34a rolls with respect to the backup surface 12a while changing the contact position as shown in FIGS. 3 to 5, for example, so that the backrest 3 can change its direction as indicated by an arrow in FIG. .

  Further, in the present embodiment, as shown in FIGS. 2, 3, 6, and 7 and the like, an auxiliary member 35 having an angular cross section is integrally formed at a position continuous with the movable member 34 when the backrest inner shell 31 is formed. is doing. The auxiliary member 35 is provided with a regulating surface 35a at a position where a predetermined gap P (see FIG. 7) is formed between the auxiliary surface 35a and the regulating surface 35a in a region extending from the center in the width direction to the end. Two gently curved surfaces that protrude rearward are connected to each other, and the gap P is released downward. Then, by covering the movable member 34 and the auxiliary member 35 on the backup member 12 from above, the backup surface 12a is accommodated in the gap P between the movable surface 34a and the regulating surface 35a so as to be capable of relative swinging. That is, in the state of FIG. 3 in which the movable surface 34a is not oscillating, a clearance C is secured at least in a portion other than the center in the width direction between the backup surface 12a and the regulating surface 35a, and the oscillating end shown in FIG. The restricting surface 35a is brought into contact with the backup surface 12a to restrict further swinging of the movable surface 34a. In the drawing, the edge 35ax of the regulating surface 35a is locally in contact with the backup surface 12a, but it may be made to contact widely along the curve. Further, an urging means 36 made of a compressible material such as urethane or a spring material is interposed in the central portion in the width direction between the backup surface 12a and the regulating surface 35a. The movable surface 34a is pressed against the backup surface 12a by urging.

Further, as shown in FIGS. 2 and 4, the backrest 3 is provided with a shaft portion 37, which is a base point that can be a pivotal fulcrum on the right and left edges near the lower end, on the back support 1 side. It is fixed after passing through a long hole 141a extending in the substantially vertical direction of the bearing member 14 provided, and using the lower end of the long hole 141a as the bearing portion 14x, By using one as a rotation fulcrum and the other as a floating point, the backrest 3 can be rotated left and right as indicated by an imaginary line in FIG. Then, the shaft portion 37 serving as a floating point is disengaged from the bearing portion 14x and can be allowed to float along the long hole 141a to the upper end of the long hole 141a. Further, in the present embodiment, the shaft portion 37 is formed in a bolt shape to also serve as a fastener, and the backrest 3 is selectively tilted to the bearing member 14 by being tightened toward the standing wall 141. It can be fixed impossible.

The backrest 3 configured in this way is fixed at least in the front-rear direction to the back support 1 side via the shaft portion 37 and the bearing member 14 even when the backrest 3 is tiltable. The movable surface 34a is basically not constrained other than at least contacting the backup surface 12a in the front-rear direction. For this reason, when a biased load as shown by an arrow W in FIG. 5 acts on a position displaced from the center in the width direction with respect to the backrest 3 from the seated person, the backrest inner shell mainly constituting the backrest 3 The upper surface of the backrest 3 is twisted and deformed downward using the elasticity of 31 and the movable surface 34a is rolled while moving the contact portion with respect to the backup surface 12a. The direction of the upper part of will be changed to the left and right.

In addition, when the seated person performs a behavior of rising right shoulder or descending right shoulder, and a biasing force (for example, an arrow T in FIG. 4) in the direction of turning clockwise or counterclockwise in the back view acts on the backrest 3. The backrest 3 rotates through the shaft portion 35 and the bearing member 14, and the centerline m that vertically cuts the center in the width direction is shown as an imaginary line in FIG. It is designed to be able to be tilted by following the downward movement of the shoulder. The tilted backrest 3 may be returned to the normal position by placing a resin spring or the like at an appropriate site.

In addition to such a configuration, the present invention for positioning the lumbar support 4 and guiding it in the vertical direction using the bracket 13 as shown in FIG. The guide member 5 which is a guide part which concerns on is attached. This guide member 5 is made of a resin, and a metal support shaft 6 for wearing a lumbar support shaft is inserted into a long hole 5a formed between opposing walls 51 and 52 which are paired in the front and rear as shown in FIG. A part thereof constitutes a vertical positioning mechanism A for the lumbar support 4 in cooperation with the support shaft 6.

The vertical positioning mechanism A is a partially cylindrical recess provided at an intermittent position along the vertical direction on the front surface of the opposing wall 52 of the guide member 5 to engage the support shaft 6 with the support shaft 6. 53. In this recess 53, the space between the opposing walls 51 and 52 is expanded in the front-rear direction.

When the plate-like elastic body 54 provided at a part of the guide member 5, specifically, at the intermediate position in the width direction of the front facing wall 51 is viewed from the insertion direction of the support shaft 6, the elongated hole 5 a is narrowed. Even if the support shaft 6 is engaged with any of the recesses 53, the support shaft 6 is elastically biased toward the recess 53 as shown in FIG. At the same time, the support shaft 6 can move between the recesses 53 and 53 against the elastic body 54 as shown in FIG. The elastic body 54 of the vertical positioning mechanism A imparts rotational resistance to the support shaft 6 by pressing the support shaft 6 against the recess 53, making it difficult to turn, so that not only the vertical position of the lumbar support 4 but also the rotation angle is provided. Temporarily holds the action.

On the other hand, the backrest 3 side is elastically deformable by providing a U-shaped slit 31b in the lumbar region 31a of the backrest inner shell 31 as shown in FIGS. The outer wall is fixed to the back support rod 1 so as to correspond to the side of the lumbar region 31a, and the lumbar support 4 is positioned so as to correspond to the lumbar region 31a. That is, the lumbar support 4 is disposed at a position where the cushion material 32 is pressed forward while elastically deforming the lumbar region 31a. Needless to say, a part of the back inner shell 31 is cut out and a resin plate that can be elastically deformed is disposed so as not to hinder the corresponding structure.

With such a configuration, when the support shaft 6 moves up and down, the support shaft 6 is engaged in each recess 53 and positioning in the height direction is performed. Since the recess 53 exists in a direction urged by the elastic body 54, if a load is applied to the backrest 3 from the seated person, the support shaft 6 is more strongly pressed against the recess 53 and engaged.

  And the grip-like operation part 7 shown in FIG.1 and FIG.10 is provided in the right-and-left both ends of this support shaft 6 in the vicinity of the right and left edges of the backrest 3, and the arm is moved backward while the seated person is seated. The left and right operation parts 7 are gripped so that the support shaft 6 can be moved up and down.

  At this time, the support shaft 6 is intermittently engaged with the left and right recesses 53 as the support shaft 6 moves in the vertical direction, and every time the support shaft 6 is engaged, the support shaft 6 is click-stopped and a click feeling is felt through the support shaft 6. Therefore, the engagement between the support shaft 6 and the recess 53 serves as a clue to move the support shaft 6 while keeping the horizontal position if viewed from a different viewpoint than the positioning function. Further, since the recess 53 described above has a partially cylindrical surface extending horizontally, the shape of the recess 53 can also give a clue for guiding the support shaft 6 horizontally.

  On the other hand, as shown in FIG. 2 and the like, the lumbar support 4 in this embodiment includes a prismatic block portion 41 and a support shaft mounting portion 42 formed at a portion displaced from the column axis n of the block portion 41 as a resin. It is formed by integral molding, and is provided with an anti-rotation portion 43 by a screw or the like for axially attaching the support shaft 6 to the support shaft mounting portion 42, and the substantially flat surface of each block portion 41 is shown in FIGS. A support surface S (S (1), S (2), S (3), S (4)) as shown in (d) is provided, and a rounded corner R is provided between the adjacent support surfaces S, S. ing. The support shaft 6 is attached to the support shaft mounting portion 42, and both are fixed by a rotation preventing portion 43 so as to be integrally rotatable.

That is, each support surface S is a pressure receiving surface that receives the load F evenly as shown in FIG. 11A at a predetermined rotational position, and as shown by an arrow V in FIG. When the support 4 is about to be rotationally displaced, the region that moves forward by the rotation (the lower half of the support surface S in the figure) approaches the backrest 3 and moves backward by the rotation (the upper surface of the support surface S). The load F is received with priority over the half). In other words, when each support surface S is a pressure receiving surface, the lumbar support 4 is stabilized in a posture in which the portion having the smallest distance from the support shaft 6 is the center position of the pressure reception, and from there, the lumbar support 4 is supported by the support shaft 6. If the occupant tries to rotate in the direction that increases the distance from the occupant, a pressing force is generated in the direction that reduces the distance from the seated person to the lumbar support 4, and the lumbar support 4 attempts to return to a stable direction. The operation of stably holding the lumbar support 4 at the predetermined rotational position is performed. Since the distance L (L (1), L (2), L (3), L (4)) from the support shaft 6 of the support surface S is basically different as shown in FIG. The protrusion amount (that is, L) of the support surface S can be changed depending on whether the surface S (S (1), S (2), S (3), S (4)) is a pressure receiving surface.

  When the above-described operation unit 7 is seated and gripped with both hands and a rotation operation is performed, the lumbar support 4 rotates together with the support shaft 6 so that a desired support surface S can be selected.

Even when no load is applied to the backrest 3 from the seated person, even when the support surface S (3) having the smallest protrusion amount becomes the pressure receiving surface, the resin plate 31a on the back surface of the backrest 3 is pressed to provide a cushioning material. The position of the support shaft 6 is defined so that 32 is in a slightly compressed state. Further, the support surfaces S (2) and S (4) are set at the support shaft 6, and the distances L (2) and L (4) therefrom are the same in this embodiment (FIG. 12). (See (b) and (d)), since the height position with respect to the support shaft 6 when these become the pressure receiving surface is different, it has a simple height position changing function using rotation. it can.

  Then, the outer cover 9 shown in FIGS. 13, 14 (a) and 15 (a) is placed at a position where the mechanical parts attached to the back surface of the backrest 3 and the back support rod 1 configured as described above are concealed. It is arranged.

The outer cover 9 is attached to the back support rod 1 so as not to come into contact with the backrest inner shell 31 because the outer cover 9 is cut off from the backrest inner shell 31. That is, as described above, the back shell inner shell 31 is movable, while the outer shell 9 is held stationary, and the left and right side edges 31x of the back shell inner shell 31 correspond to the outer cover 9. The relative movement toward or away from the side edge 9x is performed. For this reason, interference between the backrest inner shell 31 and the outer cover 9 or interference between mechanical components such as the back support device 2 and the lumbar support 4 provided on the back surface of the backrest inner shell 31 and the outer cover 9 does not occur. In the range, an operation space Z that allows the relative movement of the backrest inner shell 31 is secured with a space between the backrest inner shell 31 and the outer cover 9.

However, if the space is simply left, the entire operation space Z is opened to the side, and various mechanical parts are visually recognized from the side surface, which makes it unsightly. Therefore, in this chair, the rib-shaped cover 31z protrudes rearward from the back surface in the vicinity of the side edge 31x of the backrest inner shell 31, and forward (obliquely forward) from the front surface of the back support rod 1 and the side edge 9x of the outer cover 9. The rib-shaped covers 1z and 9z are projected toward each other, and the rib-shaped covers 31z and 1z and the rib-shaped covers 31z and 9z overlap each other as viewed from the side as shown in FIG. The shielding mechanism SL is configured by arranging them. The shielding mechanism SL shields the side of the operation space Z without disturbing the operation of the backrest inner shell 31.

As shown in FIGS. 16 and 17, the left and right rib-shaped covers 31z of the backrest inner shell 31 are connected by a rib-shaped cover 31z ′ whose upper end is protruded substantially horizontally above the back support device 2, and is entirely This constitutes a downward U-shaped rib-shaped cover, which is integrally formed with the backrest inner shell 31.

The rib-like cover 1z of the back support rod 1 is integrally formed on the outer edge side of the above-described guide member 5 (see FIG. 18) for guiding the support shaft 6 of the lumbar support 4, and is a plate protruding forward from a predetermined upper and lower region. 14 (a) and 15 (a), the backrest inner shell 31 is inserted into the rib-shaped cover 31z with a predetermined distance therebetween.

  Further, as shown in FIGS. 13 and 14A, the rib-like cover 9z of the outer cover 9 protrudes obliquely forward from the left and right side edges 9x in the vicinity of the upper side of the outer cover 9. The rib-shaped cover 9z is located at a position continuous with the rib 9r bulged along the width direction at the portion corresponding to the back support device on the outer cover 9 side, and is disposed outside the rib-shaped cover 31z of the backrest inner shell 31. To be.

  Then, when the back inner shell 31 performs a twisting operation, when the side edge 31x approaches the corresponding side edge 9x of the outer cover 9 as shown on the left side edge of FIG. The rib-shaped cover 31z of the bent inner shell 31 does not interfere with the rib-shaped cover 1z of the back support rod 1, and the overlap in the side view is deepened. Even if the edge 31x is separated from the corresponding side edge 9x of the outer cover 9, such that the rib-like cover 31z of the backrest inner shell 31 remains overlapped with the rib-like cover z of the back support rod 1 in a side view. The protrusion amount and positional relationship of the rib-shaped covers 31z and 1z are defined. Similarly, when the backrest inner shell 31 performs a twisting operation and the side edge 31x approaches the corresponding side edge 9x of the outer cover 9 as shown in FIG. The rib-like cover 31z of the shell 31 does not interfere with the rib-like cover 9z of the outer cover 9 so as to deepen the overlap in side view, and as shown in FIG. Even if the outer cover 9 is separated from the corresponding side edge 9x of the outer cover 9, the rib-shaped cover 31z of the backrest inner shell 31 remains overlapped with the rib-shaped cover 9z of the outer cover 9 in a side view. The protrusion amount and positional relationship of the covers 31z and 9z are defined. Of course, as long as the shielding function is not substantially impaired, the overlap between the rib-like covers when separated is almost eliminated.

  In FIGS. 1, 2 and 8, the rib-like covers 1z, 31z and 31z ′ are not shown.

  1 and 2, the back of the upholstery 33 is wound around the back of the ribbed covers 31z and 31z 'of the inner shell 31 so that the rib-shaped covers 31z and 31z' It should be fastened while surrounded. Thereby, it is difficult to visually recognize the end of the upholstery 33, and at the same time, it is possible to avoid problems such as the upholstery 33 entering the operation space Z and winding around the mechanical parts.

  Furthermore, as shown in FIG. 13, a hanger H is attached to the back surface of the outer cover 31 of this chair, and the flat element is held at least in the stowed position lower than the upper end of the inner shell 31 when necessary. It is designed to be used by pulling it upward.

As described above, the back support device 2 of the present embodiment includes the backup surface 12a formed on the back support rod 1 side, and is attached to the backrest 3 side in contact with or close to the backup surface 12a. And a movable surface 34a that can be swung. Then, gradually curved portion 12y widening the opposing distance, the provided 34y, wide load applied to the backrest 3 from the widthwise center of the backrest 3 from the seat occupant as displaced from the center in the width direction on the backup surface 12a and the movable surface 34a When the direction is biased, the movable surface 34a is configured to be able to follow the left and right direction while rolling on the backup surface 12a, and from the center of the backup surface 12a and the movable surface 34a to the constant region in the width direction. The extending part (12x, 34x) is formed on a flat surface parallel to each other .

In other words, when the seated person leans in the backrest 3 in a normal posture, the back of the back is in contact with the vicinity of the center of the backrest 3 in the width direction. It is a natural movement that the entire back rolls on the backrest 3 while the spine moves away from the center in the width direction. According to the present embodiment, exactly the same movement can be given as the rolling motion of the movable surface 34a with respect to the backup surface 12a, and consequently the rolling motion of the backrest 3 with respect to the back support rod 1, thereby The relative relationship with the backrest 3 is kept constant, and when the seated person moves, the backrest 3 follows and does not get in the way, and an excellent effect of maintaining an appropriate support state can be achieved. . In addition, since the portions (12x, 34x) extending from the center of the backup surface 12a and the movable surface 34a to the constant region in the width direction are formed on flat surfaces parallel to each other, the backrest 3 is in a state where the seated person is normally seated. Even if the center of the load applied to the head is moved in small increments in the width direction, the backrest 3 can be prevented from reacting one by one and a stable seating state can be ensured.

  In particular, since the movable surface 34a is provided at the upper part of the backrest 3 and the backup surface 12a is provided at a position facing the movable surface 34a, the present invention is effectively supported by appropriately supporting the vicinity of the scapula which is largely displaced by the movement of the seated person. It can be announced.

  Specifically, since the distance d between both surfaces is gradually increased from the center in the width direction by making the curvatures of the backup surface 12a and the movable surface 34a different, the environment required for rolling can be simplified. It can be easily realized through integral molding or the like.

  In this case, since the parts (12x, 34x) extending from the center of the backup surface 12a and the movable surface 34a to the constant region in the width direction are formed in parallel to each other, the seat occupant is placed on the backrest 3 in a normally seated state. Even if the center of the load moves in the width direction in small increments, the backrest 3 can be prevented from reacting one by one, and a stable seating state can be ensured.

  Also, the lower part of the backrest 3 is fixed to the back support 1 side at least in the front-rear direction, the upper part is released, and the elasticity of the backrest 3 against the load W which is biased in the width direction applied to the backrest 3 from the seated person. The fact that the upper part of the backrest 3 is torsionally deformed downward is also effective. When a seated person is drowning in one elbow or looking diagonally backward, the area around the waist does not move much, and the area around the shoulder blade moves greatly, so if it is configured as described above, it will better fit the body movement and backrest This is because by twisting and deforming 3, the backrest 3 can be effectively returned to its normal shape using the elastic restoring force of the backrest inner shell 31.

  Further, a predetermined gap P is formed between the movable surface 34a, and a regulating surface 35a that accommodates the backup surface 12a in the gap P so as to be relatively swingable is provided integrally with the movable surface 34a. Since the restricting surface 35a is brought into contact with the backup surface 12a at the swing end to restrict further swing of the movable surface 34a, the movable range of the movable surface 34a that moves two-dimensionally rolls. It can be effectively limited without interfering with the operation.

  Furthermore, since the urging means 36 that presses the movable surface 34a against the backup surface 12a is interposed between the backup surface 12a and the regulating surface 35a, the movable surface 34a flutters against the backup surface 12a or makes contact noise. It is possible to effectively prevent an unpleasant sensation due to, for example, giving a good feeling of use of the chair.

  The specific configuration of each unit is not limited to the above-described embodiment.

  For example, without using the rolling operation between the surfaces as described above, for example, as shown in FIG. 19, the movable part A34 and the backup part A12 are connected by link elements A21 and A22 having appropriate lengths. Even if the four-point link is configured, it is possible to realize the operation of changing the direction while the movable part A34 swings to the left and right, and it is possible to obtain the effects similar to the above. The point is that the seat support device A2 of the present invention has the center in the width direction of the movable part A34 set on the backrest side when the center of the load applied from the seated person to the backrest 3 is biased in the width direction. As long as the function of moving the entire movable portion A34 in the direction and following the entire movable portion A34 can be brought in between the backup portion A12 on the back support rod 1 side, other various configurations can be employed.

  Further, the seat support device B2 can be configured using the same principle as that of the back support device A2. That is, in the seat 8 as well, the posture change such as sometimes taking a forward leaning posture and sometimes extending the foot in a long-time desk work or the like is a natural movement, and accordingly, the load is moved back and forth and the load applied from the buttocks. Is biased in the same direction from the central part in the front-rear direction of the seat. Therefore, for example, as shown in FIG. 20, link elements B21 and B22 similar to the link elements A21 and A22 are interposed between the backup part B12 set on the seat receiving side and the movable part B34 set on the seat 8 side. When the center of the load is biased in the front-rear direction, the center of the movable part B34 is moved in the biased direction while changing the direction of the entire movable part B34 in the forward or backward tilt direction. Even if it is made to do, it can respond appropriately to a motion of a seated person. It goes without saying that such a configuration can be realized in the same manner even if the rolling operation between the members described above is used.

Such a configuration is also useful when applied to the width direction of the seat 8. That is, when a seated person takes a resting posture, for example, by crossing his legs, the load applied from the buttocks is usually biased to a position displaced in the same direction from the center in the width direction of the seat. In such a case, if the configuration of FIG. 20 is rotated 90 ° in plan view and applied, the seat 8 can follow the movement of the seated person and an appropriate backup state can be obtained.

  Further, when the rolling function is used, the backup surface C12 can be established even when the curvature is larger than the movable surface C34 as shown in FIG. 21, and one of the surfaces is a flat surface as shown in FIG. In addition, a mode in which the other is a curved surface is also included.

In addition to the above, to even the central portion of the movable surface and the backup surface is not row flat can be stably region that does not roll if the same curvature, back支桿shape T-shaped, or the entire plate It may be an eggplant.

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

  For example, in the above embodiment, the rib-like cover 1z is provided on the back support rod 1, but it may be provided on the outer cover 9 side. Similarly, the rib-shaped cover 9z can be provided on the back support rod 1 side.

  Further, as another form of the outer cover, it has a wall portion projecting in a circular shape toward the backrest, and the back support rod is arranged on the left and right outer sides of the wall portion so as to be concealed from the rear, and the wall A structure in which the above-described mechanism component is accommodated inside the portion is conceivable. Even in this case, the inside of the wall portion can be used as an operation space, and the wall portion can be used as a rib-shaped cover. In this case, it is preferable that the above-described upholstery 33 is wound around the backrest and attached in a state of surrounding the wall portion in close contact with the wall portion.

The perspective view of the chair concerning one embodiment of the present invention. The exploded perspective view. The top view which fractured | ruptured the same part. The rear view. FIG. The side view which fractured | ruptured the same part. The principal part enlarged view of FIG. The expansion perspective view of the guide member in the embodiment. Action | operation explanatory drawing of the vertical positioning mechanism in the embodiment. Explanatory drawing of the operation part in the same embodiment. Action | operation explanatory drawing of the lumbar support in the embodiment. Action | operation explanatory drawing of the lumbar support in the embodiment. The perspective view of the chair which attached the outer cover. The same side view. XX sectional drawing in FIG. The rear view of the chair which removed the outer cover and clearly showed the rib-shaped cover. The exploded view. The figure which shows the relationship between a guide member and a rib-shaped cover. The figure which shows the modification of this invention. The figure which shows the other modification of this invention. The figure which shows the modification other than the above of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Back support 2 ... Back support device 3 ... Backrest 12a ... Backup surface 12y ... Curved part 34a ... Movable surface 34y ... Curved part

Claims (5)

A backup surface formed on the back support side, and a movable surface attached to the backrest side so as to contact or be close to the backup surface and swingable with the backrest, at least one of the backup surface and the movable surface When the load applied to the backrest from the seated person is biased in the width direction from the center of the backrest in the width direction, a movable surface is provided. It is configured to be able to follow the left and right direction while rolling on the backup surface, and the part extending from the center of the backup surface and the movable surface to the constant region in the width direction is a flat surface parallel to each other or a curved surface having the same curvature. A back support device characterized by forming . A predetermined gap is formed between the movable surface and a regulating surface that accommodates the backup surface in a relative manner so as to be able to swing relative to the gap is provided integrally with the movable surface. The back support device according to claim 1, wherein the swinging of the further movable surface is regulated by contacting the back surface of the back support device. The back support device according to claim 2, wherein an urging means for pressing the movable surface against the backup surface is interposed between the backup surface and the regulating surface . The backrest is fixed at least in the front-rear direction on the back support side and released upward, and uses the elasticity of the backrest against the uneven load in the width direction applied to the backrest from the seated person. The back support device according to any one of claims 1 to 3, wherein the upper part of the backrest is torsionally deformed downward . A chair comprising the back support device according to claim 1.

Images