JP5635572B2 - Chair seat structure - Google Patents

Description

  The present invention relates to a seat structure of a chair that supports a hip and a thigh of a seated person.

  Low back pain may be caused by continuous office work for a long time while sitting on a chair. In particular, along with the spread of personal computers to general households, back pain may develop due to continuous use of the personal computer for a long time while sitting on a chair even in general households. Contributes to an increase in back pain.

  An example of a mechanism for developing such back pain will be described with reference to FIGS.

  FIG. 6 is a diagram illustrating an outline of a standing posture before sitting. As shown in the figure, in the standing posture, the lumbar vertebra 122 of the vertebra 120 of the person 110 is bunched and the entire vertebra 120 is substantially S-shaped as indicated by a lumbar shape line x indicating the outline of the shape of the lumbar vertebra 122. It has become. At this time, as shown in FIG. 9A for explaining the outline of the configuration of the lumbar vertebra 122, the intervertebral disc 124 between the vertebrae 122a composing the lumbar vertebra 122 is in a normal state where the load applied to the intervertebral disc 124 is small, and the vertebra 122a The shock is appropriately absorbed.

  FIG. 7 is a diagram illustrating an outline of a sitting posture when properly seated on a chair. As shown in the figure, in the sitting position where the back portion 114 is not bent forward, the upper portion of the pelvis 118 located in the buttocks 112 is prevented from rotating backward, and is linked to the pelvis 118 as shown by the lumbar shape line x. The lumbar vertebrae 122 of the vertebrae 120 are prepared.

  At this time, as shown in FIG. 9 (a), the intervertebral disc 124 is not compressed between the vertebrae 122a and is maintained in a normal state with a low load, and this state is maintained in order to prevent the onset of low back pain and the like. Is desirable.

  FIG. 8 is a diagram illustrating an outline of an inappropriate sitting posture. As shown in the figure, when the back portion 114 is supported on the backrest portion 104 of the chair 100, for example, by sitting for a long time, the upper portion of the pelvis 118 is indicated by the arrow D due to the extension of the buttocks muscle group 112a, the extension of the hamstrings 116, and the like. As shown in FIG. As the upper part of the pelvis 118 rotates backward, the lumbar vertebra 122 of the spine 120 associated with the pelvis 118 is kyphosis, as indicated by the lumbar shape line y.

  At this time, as shown in FIG. 9B, the intervertebral disc 124 between the vertebrae 122a constituting the lumbar vertebra 122 is pressed between the vertebrae 122a by the vertebrae 122a and is loaded. If this state continues for a long time, low back pain develops. Further, if such a state continues for a long period of time, the intervertebral disc 124 may be degenerated, leading to the onset of intervertebral hernia. In order to avoid such a state, there are various chairs that maintain an appropriate sitting posture.

  Patent Document 1 discloses a front side seating surface having a substantially horizontal seating surface that supports the front part of the buttocks and the thigh of the seated person, and a rear side that is provided behind the front side seating face and supports the rear part of the buttocks of the seated person. A chair with a seating surface is disclosed.

  According to the chair of this patent document 1, since the rear seating surface is provided to be inclined with respect to the front seating surface, and the tilt angle can be freely displaced, the pelvic angle of the seated person and the rear seating surface Can be adjusted so that the inclination angle coincides with the inclination angle, and the sitting comfort is improved.

  Patent Document 2 discloses a seat cushion front part that supports the front part and thigh part of the seated person and the front side is lifted with respect to the rear side, and a seat cushion part that is provided behind the front part of the seat cushion. A vehicle seat having a rear portion of a seat cushion that supports the rear portion is disclosed.

  According to the vehicle seat disclosed in Patent Document 2, the rear portion of the seat cushion is provided to be inclined with respect to the front portion of the seat cushion, and the inclination angle can be freely displaced. The seating angle of the buttocks is changed to prevent the pelvis from rotating backwards.

JP 2002-119369 A JP-A-8-126548

  According to the chair of Patent Document 1, the sitting comfort of a seated person is improved, and according to Patent Document 2, backward rotation of the pelvis is prevented.

  However, according to the chair of Patent Document 1, the seat surface of the front seating surface is configured to be substantially horizontal, and according to the vehicle seat of Patent Document 2, the front side of the seat cushion front part is lifted with respect to the rear side. It has been.

  Accordingly, in the sitting position, the thigh of the seated person is substantially horizontal or lifted forward, and the natural forward tilting posture of the upper body of the seated person cannot be obtained. Rotation cannot be effectively suppressed. As a result, it is considered that the ideal lordosis of the lumbar spine cannot be obtained.

  The present invention has been made in view of the above problems, and the object thereof is to effectively suppress the backward rotation of the upper part of the pelvis and to maintain the sitting posture in which the lumbar vertebra of the spine linked to the pelvis is in a forward position. An object of the present invention is to provide a seat structure for a chair.

In order to achieve the above object, the invention according to claim 1 includes a rear seat portion that supports the rear portion of the seat occupant from behind, and a front side of the rear seat portion that is provided in front of the seat occupant. A rear seat rotating mechanism that displaces and fixes the rear seat to a plurality of positions by a rotating operation. The rear seat rotation mechanism includes a pair of fixing portions disposed at both ends of the front seat portion in the seat width direction and fixed to a seat frame of a chair on which the front seat portion is disposed; and the rear side A pair of pivot arms that extend in the front-rear direction of the rear seat at both ends in the seat width direction of the seat and are attached to the rear seat, and the seat width of the rear seat between the pivot arms A rod-shaped gripping portion that extends in the direction, and each of the fixing portions and each of the rotating arms is attached via a lock mechanism. The locking mechanism, the said respective rotary arm is rotatable relative to the fixing portions, and are fixably form respective rotating arm at a plurality of locations, the rear side by the rear seat portion pivoting mechanism The seat is configured to rotate about an axis in the seat width direction set on the front side of the rear seat, and to be fixed at the rotated position, and the front seat has a seat surface height of the seat. It is formed so that it may fall gradually as it shifts from the rear side to the front side of the front seat portion.

  According to this configuration, in the seated state, the rear part of the buttocks of the seated person is supported from the rear by the rear seat part, and the front part of the buttocks and the thigh are supported by the front seat part. At this time, since the rear part of the buttocks is pushed and supported by the rear seat part, the change of the sitting posture is promoted, and the backward rotation of the pelvis located at the hip part, that is, the upper part of the pelvis is prevented from rotating backward. The Thereby, the state where the lumbar vertebra of the spine linked to the pelvis is in the lordosis can be maintained.

  Further, the seat surface of the front seat portion is formed such that the seat surface height gradually decreases as the front seat portion moves from the rear side to the front side, so that the thigh is inclined forward in the sitting posture. Thus, a natural forward leaning posture of the upper body of the seated person can be obtained.

Therefore, in the state in which the upper body is tilted forward, the rear part of the buttocks is pushed and supported from the rear of the rear part of the buttocks, so that the rearward rotation of the upper part of the pelvis can be effectively suppressed. In addition, since the rear seat is provided with a rear seat rotation mechanism that displaces and fixes the fixed position of the rear seat to a plurality of positions by the pivoting operation of the rear seat, the collar corresponding to the body shape or physique of the seated person Rear support can be provided. In addition, the rear seat portion rotation mechanism includes a rotation arm that can rotate with respect to the fixed portion, and the rotation arm is provided with a rod-shaped grip portion, so that the grip portion is gripped. Thereby, even if it is in the sitting state, the rear seat portion can be easily rotated and displaced and fixed at a plurality of positions.

According to a second aspect of the present invention, in the seat structure of the chair according to the first aspect, the rear seat has a seat surface curved in a concave shape.

  According to this configuration, when the seated person is seated, even if the rear seat is pushed and supported by the rear seat, the seat surface of the rear seat is formed in a concave shape. The rear and seating fit well. Therefore, the uncomfortable feeling at the time of sitting is relieved and favorable sitting comfort is ensured.

  According to the present invention, the rear seat portion is pushed and supported from the rear by the rear seat portion to adjust the sitting posture, and the seat surface height gradually decreases as the front seat portion moves from the rear side to the front side. With the front seat portion formed in this manner, the seated person can obtain a natural forward tilt posture of the upper body in the sitting posture.

  Accordingly, since the posterior part of the buttock is pushed and supported from the rear of the posterior part of the buttock while the upper body is tilted forward, the backward rotation of the upper part of the pelvis is effectively suppressed, and the lumbar vertebra of the spine linked to the pelvis is It is possible to maintain a good state of the heel.

  As a result, the load applied to the intervertebral disc between the vertebrae constituting the lumbar vertebra can be suppressed, and the intervertebral disc can be maintained in a normal state. Thereby, the malfunction of the lower back part, such as a back pain and an intervertebral disk hernia, can be suppressed.

It is a figure explaining the outline of the seat part structure of the chair which concerns on embodiment of this invention. Similarly, it is a figure explaining the outline of the seat part structure of a chair, (a) is the figure which looked at the seat part structure from the front, (b) is the figure which looked at the seat part structure from the back. It is a figure explaining the outline of the chair which concerns on this Embodiment. Similarly, it is the figure which looked at the chair which concerns on this Embodiment from the downward direction. It is a figure explaining the outline when a person sits on a chair. It is a figure which shows an example of the mechanism in which low back pain develops, and shows the outline of the standing posture before sitting. Similarly, it is a figure showing an outline of a sitting posture when properly sitting on a chair, explaining an example of a mechanism for developing back pain. Similarly, it is a figure showing an outline of an improper sitting posture explaining an example of a mechanism in which low back pain develops. It is a figure explaining the outline of a structure of a lumbar vertebra, (a) is a figure which shows the outline of the state in which the lumbar vertebrae was prepared, (b) is a figure which shows the outline of the state in which the lumbar vertebra was backed.

  Next, an embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 is a diagram illustrating an outline of a seat structure of a chair according to an embodiment of the present invention. As illustrated, the seat structure 20 is used as a seat of the chair 10. The seat structure 20 is provided on the rear seat portion 30 that supports the rear portion of the seated person's buttocks, and on the front side of the rear seat portion 30, that is, on the front end 36 side of the rear seat portion 30. A front seat 40 that supports the front and thighs is provided.

  Note that the rear part of the buttocks refers to the rear side of the chair 10 indicated by the arrow line R in the buttocks of the seated person in the sitting position, and the front part of the buttocks part of the chair 10 indicated by the arrow line F in the buttocks of the seated person in the sitting position. Point forward.

  The rear seat portion 30 is rotated around an axis in the seat width direction set in the vicinity of the front end 36 of the rear seat portion 30, that is, the front side of the rear seat portion 30, and can be fixed at the rotated position. The front seat 40 gradually decreases as the height of the seating surface 42a of the front seat 40 shifts from the rear end 44 on the rear side of the front seat 40 to the front end 46 on the front side. Is formed.

  The seat structure 20 further includes a rear seat rotation mechanism 50 that rotates the rear seat 30 to be displaced and fixed at a plurality of positions. As will be described later, the rear seat portion rotation mechanism 50 sets the seat width direction axis O on the front side of the rear seat portion 30.

  Next, a specific configuration of each part of the seat structure 20 in the present embodiment will be described. 2A and 2B are diagrams for explaining the outline of the seat structure 20, wherein FIG. 2A is a diagram of the seat structure 20 viewed from the front surface, and FIG. 2B is a diagram of the seat structure 20 viewed from the back surface.

  As shown in FIG. 2A, the rear seat portion 30 is formed, for example, by covering a flat base material (not shown) with a pad formed of urethane foam obtained by foaming a foamed resin material. The rear seat portion 30 includes a seat surface 32a formed so that the center portion is curved in a concave shape and fits the rear portion of the buttock. That is, the seat surface 32a is formed in a shape that follows the rear portion of the buttocks.

  The front seat portion 40 is formed, for example, by covering a flat substrate (not shown) with a pad formed of urethane foam obtained by foaming a foamed resin material. The front seat portion 40 includes a seat surface 42a that is gradually inclined downward from a horizontal plane as it goes from the rear end 44 side to the front end 46 side.

  That is, the seating surface 42 a is formed such that the seating surface height gradually decreases as it moves from the rear end 44 to the front end 46 of the front seat portion 40. In the present embodiment, the inclination of the seating surface 42a is set within 2.5 ° from the horizontal plane.

  The seat surface 42a has a concave central portion and is formed so as to fit from the front of the buttocks to the thigh. The seat surface 42a is set to have a length (seat surface length) from the front end 46 to the rear end 44 such that a sciatic nodule located at the lower portion of the human buttocks rides when seated. In the present embodiment, the seating surface length is set in a range of approximately 304 mm to 381 mm, preferably 342 mm.

  As shown in FIG. 2B, the rear seat rotation mechanism 50 is disposed below the front seat 40 at both ends in the seat width direction of the front seat 40 and extends in the seat surface length direction of the front seat 40. A pair of fixing portions 52-1 and 52-2 are provided. A pair of rotating arms 54-1 and 54-2 are respectively connected to the fixing parts 52-1 and 52-2 via a pair of locking mechanisms 56-1 and 56-2. -2 is pivotally supported with respect to -2. In other words, the rotating arms 54-1 and 54-2 rotate around the axis O between the locking mechanisms 56-1 and 56-2.

  The rotating arms 54-1 and 54-2 are respectively connected to the base portion 54a and the rear end portion of the base portion 54a that are pivotally supported by the fixing portions 52-1 and 52-2 via the lock mechanisms 56-1 and 56-2. It has the standing part 54b which is formed continuously with the base part 54a and rises and inclines toward the rear end 34 side of the rear seat part 30.

  The upright portion 54 b is attached to the back surface 32 b of the rear seat portion 30, and the rotating arms 54-1 and 54-2 are arranged at both ends in the seat width direction of the rear seat portion 30 in front of and behind the rear seat portion 30. It extends in the direction.

  A round bar-shaped gripping portion 58 extending in the seat width direction of the rear seat portion 30 is installed between the rear end portions of the upright portions 54b of the rotating arms 54-1 and 54-2.

  Each of the lock mechanisms 56-1 and 56-2 is a mechanical type formed so that the respective rotation arms 54-1 and 54-2 can be locked at a plurality of rotation positions (rotation angles). The rotating arms 54-1 and 54-2 are fixed at an arbitrary rotation angle by rotating the 54-1 and 54-2 upward. On the other hand, the rotating arms 54-1 and 54-2 are fixed at an arbitrary rotation angle by once rotating the rotating arms 54-1 and 54-2 and then pressing the rotating arms 54-1 and 54-2 downward. Is released.

  In the present embodiment, as shown in FIG. 1, the seat structure 20 including the rear seat rotation mechanism 50 configured as described above has a support position for supporting the rear seat 30 and the rear portion of the buttocks from the rear. It is configured to be displaced and fixed at five support positions.

  Specifically, the lower limit position of the rear seat portion 30 where the seat surface 32a of the rear seat portion 30 and the seat surface 42a of the front seat portion 40 are substantially flush with each other is defined as the reference position P0, and the upper position from the reference position P0. In the support positions P1 to P5 that sequentially shift in the direction, the rear seat portion 30 is displaced and fixed in the vertical direction.

  Next, an outline of the chair 10 having the seat structure 20 configured as described above will be described with reference to FIGS. 3 and 4.

  FIG. 3 is a diagram illustrating an outline of the chair 10, and FIG. 4 is a diagram of the chair 10 as viewed from below. As shown in FIGS. 3 and 4, the chair 10 includes a seat structure 20, a leg 12 and a seat frame 14 that support the seat structure 20, an armrest 16 that is positioned above the leg 12 and the seat frame 14, 16 and a backrest portion 18 and generally have a form called a so-called dining chair.

  The leg portion 12 is composed of front leg portions 12A and 12A and rear leg portions 12B and 12B formed of wooden square bars. The upper portions of the front legs 12A and 12A are configured as elbows 16A and 16A, and the upper portions of the rear legs 12B and 12B are configured as back pillars 18A and 18A that are slightly bent in the rear direction R.

  The seat frame 14 includes a front seat frame 14A that connects the front legs 12A and 12A, a side seat frame 14B and 14B that connects the front legs 12A and 12A and the rear legs 12B and 12B, and a rear leg 12B. A rear seat frame 14 </ b> C that connects between 12 </ b> B is provided as a main component.

  The seat frame 14 further includes corner trees 14D and 14D that are laid between the front seat frame 14A and the side seat frames 14B and 14B to reinforce the seat frame 14, and between the side seat frames 14B and 14B. A erected cross bar 14E is provided.

  The armrest portion 16 is formed in a substantially flat shape between the upper legs of the elbows 16A, 16A and the elbows 16A, 16A and the back pillars 18A, 18A formed continuously from the front legs 12A, 12A. It is constituted by an armrest plate 16B.

  The backrest portion 18 includes a back column 18A, 18A formed continuously from the rear legs 12B, 12B, and a back plate 18B laid between the back columns 18A, 18A on the upper end side of the back columns 18A, 18A. Is done. In the present embodiment, the back plate 18B is provided between the back pillars 18A and 18A so as to be disposed at the lower part of the thoracic vertebra, and the central portion thereof is curved in a concave shape so as to fit the back of the seated person. Is formed.

  As described above, the backrest 18 is formed by slightly bending the back pillars 18A and 18A in the rearward direction R. Specifically, as shown in FIG. 1, the center portion of the back plate 18 </ b> B is set to the position of the inclined line L by being displaced from the vertical line C toward the rear direction R. The angle (backrest angle) formed between the inclined line L and the floor on which the chair 10 is placed is set to be 105 ° in the present embodiment.

  In addition, this backrest angle is an angle often employed in a general chair having a so-called dining chair form.

  A seat structure 20 used as a seat of the chair 10 is attached to the seat frame 14 and supported by the leg 12 and the seat frame 14. Specifically, the fixing portions 52-1 and 52-2 of the rear seat portion rotation mechanism 50 are attached to the attachment portions 19 provided inside the side seat frames 14B and 14B of the seat frame 14 by bolts or the like. It is attached.

  Thus, the rear seat portion 30 is attached to the seat frame 14 via a gap between the rear end 34 and the back plate 18B of the backrest portion 18. On the other hand, the rear seat portion 30 is configured to rotate about an axis O in the seat width direction set on the front side of the rear seat portion 30 and to be fixed at the rotated position.

  The front side seat portion 40 is attached and supported by a crosspiece 14E installed between the side seat frames 14B and 14B of the seat frame 14.

  Next, the case where it sits on the chair 10 which concerns on this Embodiment is demonstrated. FIG. 5 is a diagram illustrating an outline when a person 110 is seated on the chair 10. As illustrated, the rear seat portion 30 of the seat portion structure 20 is displaced and fixed to, for example, a support position P1 rotated upward from the reference position P0.

  When the rear side seat portion 30 is pivoted up and down to displace the support position, the grip portion 58 installed between the rear ends of the pivot arms 54-1 and 54-2 is gripped. It can be easily rotated.

  When the person 110 sits on the chair 10 with the rear seat portion 30 fixed at the support position P1, the rear portion of the buttocks 112 is supported by the rear seat portion 30 from the rear, and the front portion of the buttocks 112 and the thigh 130. Is supported by the front seat 40.

  At this time, the sacrum 118a of the pelvis 118 is pushed and supported by the rear seat 30 from the rear of the buttocks 112, so that when the person 110 sits on the chair 10, the support position of the rear seat 30 is supported. The change of the sitting posture is prompted so that the rear portion of the buttocks 112 is adapted to P1. Therefore, the extension of the buttocks muscle group 112a and the extension of the hamstrings 116 and the like are suppressed, and the backward rotation of the upper part of the pelvis 118 located at the buttocks 112 is suppressed. As a result, the lumbar vertebra 122 of the spine 120 linked to the pelvis 118 can be held in a lordotic state.

  On the other hand, the seating surface 42a of the front seat portion 40 is formed so that the seat surface height gradually decreases as the front seat portion 40 moves from the rear end 44 to the front end 46. Inclining forward, the upper body of the person 110 tilts forward in a natural state.

  Therefore, in the state where the upper body is tilted forward, the rear portion of the heel portion 112 is pushed and supported by the rear seat portion 30 from the rear of the rear portion of the heel portion 112, so that the upper portion of the pelvis 118 is effectively rotated backward. Even when the person 110 naturally sits on the chair 10, the lordosis of the lumbar vertebra 122 in the sitting posture can be held.

  As a result, it is possible to obtain a normal state in which the load applied to the intervertebral disc between the vertebrae constituting the lumbar vertebra 122 is reduced. Thereby, the onset of low back pain and disc herniation can be suppressed.

  Since the support position of the upper part of the collar part 112 by the rear seat part 30 can be displaced and fixed to a plurality of support positions of the reference position P0 and the support positions P1 to P5 by the rear seat part rotation mechanism 50, It is possible to support the buttocks 112 corresponding to the body shape or physique of the seated person.

  In addition, the rear seat portion rotation mechanism 50 includes a round bar-shaped gripping portion 58 installed between the rear ends of the respective rotation arms 54-1 and 54-2. The grip portion 58 can be easily gripped from the gap between the end 34 and the back plate 18B of the backrest portion 18, and the support position of the rear seat portion 30 can be easily displaced even when the seat is still seated. Can be done.

  The seat surface 32a of the rear seat portion 30 and the seat surface 42a of the front seat portion 40 are formed with a concavely curved central portion, so that when the seated person sits, the collar portion 112 and the seat surface 32a. 42a fits well. Therefore, even if the rear part of the collar part 112 is pushed and supported by the rear side seat part 30, the uncomfortable feeling at the time of sitting is relieved and a good sitting comfort is ensured.

  Since the back plate 18B is disposed below the thoracic vertebra 126 of the spine 120, the backrest 18 does not interfere with the lordosis and posterior movements of the lumbar vertebra 122 caused by the spontaneous movement of the person 110. Accordingly, it is possible to prevent the lowering of the flexibility of the muscles near the lumbar vertebra 122 due to maintaining the same sitting posture for a long time and the onset of back pain due to the deterioration of blood circulation.

  Further, the backrest portion 18 has a predetermined backrest angle that is often employed in general dining chairs, and is formed by being displaced from the vertical to the rear direction R of the chair 10, so that there is no discomfort and is good. You can get a comfortable sitting.

  In addition, this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the meaning of invention. In the above-described embodiment, the case where the seat structure 20 is configured as the chair 10 having a so-called dining chair form is described as an example. However, the seat structure 20 may be configured as a chair having a so-called desk chair form for office work. Further, the seat structure 20 may be configured as a seat chair as it is.

  In the above embodiment, the case where the rear seat rotation mechanism 50 is configured to be displaced and fixed to a plurality of support positions of the reference position P0 and the support positions P1 to P5 has been described. You may comprise as a stepless type rear side seat part rotation mechanism which can displace the support position of the collar part 112 in a stepless manner.

DESCRIPTION OF SYMBOLS 10 Chair 12 Leg 14 Seat frame 18 Backrest part 20 Seat part structure 30 Back side seat part 32a Seat surface 36 Front end 40 Front side seat part 42a Seat surface 44 Rear end (rear side)
46 Front end (front side)
50 Rear side seat part turning mechanism 52-1, 52-2 Fixing part 54-1, 54-2 Rotating arm 56-1, 56-2 Locking mechanism 58 Grasping part 110 Person 112 Buttocks 118 Pelvis 122 Lumbar vertebra 124 Intervertebral disc P1 ~ P5 Support position

Claims (2)

A rear side seat that supports the back of the buttocks of the seated person from behind,
In the seat structure of the chair provided with the front seat part provided on the front side of the rear seat part and supporting the front part of the buttocks and the thigh of the seated person,
A rear seat rotation mechanism that displaces and fixes the rear seat to a plurality of positions by a rotation operation;
The rear seat rotation mechanism is
A pair of fixing parts that are arranged at both ends of the seat width direction of the front seat part and are fixed to a seat frame of a chair on which the front seat part is arranged;
A pair of rotating arms that extend in the front-rear direction of the rear seat at both ends in the seat width direction of the rear seat and are attached to the rear seat;
A rod-shaped gripping portion that extends and extends in the seat width direction of the rear seat portion between the rotating arms, and
Each fixing part and each rotating arm are attached via a lock mechanism,
The locking mechanism is
The rotating arms can be rotated with respect to the fixing portions, and the rotating arms can be fixed at a plurality of positions.
The rear seat portion is formed by the rear seat portion rotation mechanism so as to rotate about an axis in the seat width direction set on the front side of the rear seat portion and to be fixed at the rotated position. ,
The front seat is formed such that the seat surface height gradually decreases as the front seat moves from the rear side to the front side.
A seat structure of a chair characterized by that. The rear seat is
The seat structure of the chair according to claim 1 , wherein the seat surface is formed to be concavely curved.

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