CN117322739A

CN117322739A - Posture holder

Info

Publication number: CN117322739A
Application number: CN202311529909.1A
Authority: CN
Inventors: 松下刚
Original assignee: MTG Co Ltd
Current assignee: MTG Co Ltd
Priority date: 2017-08-22
Filing date: 2017-09-26
Publication date: 2024-01-02
Also published as: CN109419205A; JP7482941B2; JP7086543B2; CN109419205B; JP2019037272A; JP2022111251A

Abstract

The invention provides a posture holder for holding the upper body of a seated person in a correct posture. The posture holder (10) is provided with: a seat (11); a backrest part (16) which is in a form of rising from the rear end part of the seat part (11); a first support part (17) which forms a backrest part (16) and is in contact with the central part of the back (52) of the sitting person (50) in the left-right direction; and a pair of second support sections (18) that form a backrest section (16) and are disposed on both the left and right sides of the first support section (17) so as to be in contact with both the left and right sides of the back (52) of the occupant (50), wherein the lowermost end (17L) of the upper edge sections of the first support section (17) is disposed at a position lower than the uppermost end (18U) of the upper edge sections of the second support section (18).

Description

Posture holder

The present application is a divisional application of the following applications:

filing date of the original application: 2017, 09, 26

Application number of the original application: 201710879424.3

Title of the original application: posture holder

Technical Field

The present invention relates to a posture holder.

Background

Patent document 1 discloses a posture holder for holding a posture of a seated person in a correct state. The posture holder is provided with: a buttock supporting part for supporting buttocks of a seated person from below; and a lumbar support portion rising from a rear edge of the hip support portion. The lumbar support portion has a height capable of supporting the lower ends of the back and the waist of the seated person, and is formed in a substantially square thick plate shape as a whole.

Prior art literature

Patent literature

Patent document 1: japanese patent laid-open publication No. 2014-12130

In the posture holder, the front surface of the lumbar support portion (the surface on which the lumbar and the back are in contact) is substantially planar as a whole, and therefore, the sitting person can easily perform an operation of tilting the upper body sideways or an operation of twisting the upper body sideways. However, since this posture holder cannot stabilize the upper body of the seated person in a correct posture, there is a concern that the seated person may maintain a posture of tilting the upper body left and right or a posture of twisting the upper body left and right for a long period of time.

Disclosure of Invention

Problems to be solved by the invention

The present invention has been made in view of the above-described circumstances, and an object thereof is to hold the upper body of a seated person in a correct posture.

Technical means for solving the problems

The posture holder of the present invention is characterized by comprising:

a seat;

a backrest portion that is raised from a rear end portion of the seat portion;

a first support portion that constitutes the backrest portion and that abuts a central portion in the lateral direction of the back of the seated person; and

a pair of second support portions that constitute the backrest portion, are disposed on both left and right sides of the first support portion, and are in contact with both left and right side portions of the back of the seated person,

the lowermost end portion of the upper edge portion of the first support portion is disposed at a position lower than the uppermost end portion of the upper edge portion of the second support portion.

ADVANTAGEOUS EFFECTS OF INVENTION

The sitting person sits with a relatively low portion of the central portion of the back being attached to the first support portion and a relatively high portion of the left and right side portions of the back being attached to the second support portion. The posture holder according to the present invention supports the back of the seated person with 3 support portions, and therefore, the upper body of the seated person can be restrained from being brought into a posture of tilting left and right or a posture of twisting left and right, and the upper body of the seated person can be held in a correct posture.

Drawings

Fig. 1 is a perspective view of the posture holder of embodiment 1.

Fig. 2 is a front view of the gesture holder.

Fig. 3 is a top view of the posture holder.

Fig. 4 is a cross-sectional view of fig. 2, with the wrapping cloth omitted, as indicated by the line A-A.

Fig. 5 is a cross-sectional view of fig. 2 taken along line B-B with the wrapping cloth omitted.

Fig. 6 is a cross-sectional view of fig. 2 taken along line C-C with the wrapping omitted.

Fig. 7 is a sectional view of fig. 2 taken along line D-D with the wrapping cloth omitted.

Fig. 8 is a sectional view of fig. 2 taken along line E-E with the wrapping cloth omitted.

Fig. 9 is a cross-sectional view of fig. 2 taken along line F-F with the wrapping cloth omitted.

Fig. 10 is a sectional view of fig. 2, taken along line G-G, with the wrapping cloth omitted.

Fig. 11 is a sectional view of fig. 3 taken along line H-H with the wrapping cloth omitted.

Fig. 12 is a sectional view corresponding to the line A-A of fig. 2 showing the use state of the posture holder.

Symbol description

10-posture holder

11 seat

16 backrest portion

17 first support part

18 second support part

The lowest end of the upper edge of the 17L first supporting part

Uppermost end of upper edge of 18U second support part

24 first bearing surface

28 second bearing surface

32 linking surface

35 seat forming plate portion

36 back-rest part forming plate part

Lower end of 36L backrest part forming plate part

37 first support plate section

38 second support plate section

50 person sitting on seat

51 buttocks

52 back

Detailed Description

In the present invention, the upper end portion of the second support portion may be curved so as to tilt obliquely rearward as going upward.

According to this configuration, when the upper body of the seated person is abutted against the backrest portion, there is no fear that the upper end edge of the second support portion will sink into the body of the seated person.

In the present invention, the seat portion forming plate portion forming the seat portion and the backrest portion forming plate portion forming the backrest portion may be connected so as to be elastically and relatively displaceable with a lower end portion of the backrest portion forming plate portion being a substantially fulcrum, the backrest portion forming plate portion may be formed of a first support plate portion forming the first support portion and a second support plate portion projecting obliquely forward from left and right side edges of the first support plate portion to form the second support portion, and a projecting dimension of the first support plate portion in a lower end side region of the second support plate portion may be gradually reduced downward.

According to this configuration, when the occupant presses the upper body against the backrest, the backrest is elastically displaced rearward about the lower end edge thereof as a substantial fulcrum. Since the protruding dimension of the first support plate portion in the lower end side region of the second support plate portion gradually decreases downward, the lower end side region of the backrest portion constituting plate portion is also elastically deformed. This prevents stress from concentrating on the lower edge of the backrest portion constituting plate portion.

In the present invention, a first support surface of the first support portion facing the back and a second support surface of the second support portion facing the back may be connected via a pair of left and right connecting surfaces, and a curvature of the first support surface and a curvature of the second support surface may be smaller than a curvature of the connecting surfaces in a plan view.

According to this configuration, the back does not contact the connecting surface having a large curvature, and therefore the upper body of the seated person can be stably supported at 3 positions of the first support surface and the pair of left and right second support surfaces.

Example 1 >

Next, with reference to fig. 1 to 12, example 1 embodying the present invention will be described. In the following description, the front-rear direction is defined as the left direction in fig. 4 to 6 and 12 and the lower direction in fig. 3 and 7 to 10. The directions of the vertical directions in fig. 1, 2, 4 to 6, 11, and 12 are defined as the directions of the vertical directions. The directions appearing in fig. 2, 3, and 7 to 11 are defined as the right and left directions.

The posture holder 10 of the present embodiment 1 is configured in a laterally symmetrical shape from the shape and function of the seat portion 11 and the backrest portion 16, the seat portion 11 supporting the buttocks 51 of the seated person 50 from below, and the backrest portion 16 supporting the back 52 of the seated person 50 from behind. The seat portion 11 and the backrest portion 16 are integrated. In this embodiment 1, "the back 52 of the sitting person 50" is defined as the back and the waist of the sitting person 50 (the back side and the side surface side of the trunk in the upper body).

The shape of the seat 11 in plan view will be described. As shown in fig. 3, the rear end side support region 12R, which is approximately 2/3 of the front from the rear end of the seat 11 in the front-rear direction, has an approximately trapezoidal shape that gradually widens toward the front. In the rear end side support region 12R, the width dimension (the dimension in the lateral direction) of the seat portion 11 is maximized. The outer peripheral edge of the front end side support region 12F in front of the rear end side support region 12R in the seat portion 11 is composed of a pair of front side bent edge portions 13 and front edge cutout portions 14 that are bilaterally symmetrical. The front bent edge portion 13 is connected to both left and right side edges of the rear end side support region 12R, and constitutes a front edge portion of the seat portion 11. The front edge notch 14 is formed in a shape recessed at the center of the seat 11 in the lateral direction so as to form an obtuse angle, and connects the left and right front curved edge portions 13.

The front view of the seat 11 will be described. As shown in fig. 2 and 11, the seat portion 11 is composed of a pair of laterally symmetrical support portions 15 curved so that the upper surface side thereof is recessed. The seat portion 11 is high at the left and right direction central portion and the left and right end portions, and therefore can stably support the buttocks 51 and the root portions of the thighs of the seated person 50.

As shown in fig. 1 and 4, the backrest 16 is raised upward from the rear end of the seat 11. The backrest portion 16 is constituted by a first support portion 17 and a pair of laterally symmetrical second support portions 18, the first support portion 17 constituting a laterally central portion of the backrest portion 16, and the pair of second support portions 18 constituting left and right side edge portions of the backrest portion 16. The left and right second support portions 18 extend obliquely forward from the left and right side edges of the first support portion 17 in a cantilever manner. The extending direction of the two left and right second support portions 18 is a direction in which the interval between the two left and right second support portions 18 in the plan view gradually increases toward the front.

The front surface of the backrest portion 16 becomes the bearing surface 19 that contacts or opposes the back 52 of the occupant 50. The front view of the support surface 19 (backrest 16) will be described. As shown in fig. 2 and 11, the lower end side support region 20 extending from the lower end of the backrest 16 to approximately 2/3 of the upper side is substantially trapezoidal and gradually widens upward in the vertical direction (height direction). The outer peripheral edge of the upper end side support region 21 above the lower end side support region 20 in the backrest portion 16 is constituted by a pair of upper side bent edge portions 22 and upper edge notch portions 23 which are bilaterally symmetrical. The upper bent edge 22 is connected to the left and right side edges of the lower end support region 20, and constitutes the upper edge of the backrest 16. The upper notch is formed in a shape recessed at an obtuse angle in the center of the backrest 16 in the lateral direction, and connects the left and right upper bent edge portions 22.

The upper bent edge portion 22 is formed only on the outer peripheral edge of the second support portion 18. The upper edge notch portion 23 constitutes the entire area of the upper edge portion of the first support portion 17 and a part of the upper edge portion of the second support portion 18. The height dimension of the upper edge portion of the backrest portion 16 is largest at the upper end of the upper bent edge portion 22, and smallest at the lowermost end (the center in the lateral direction of the backrest portion 16) of the upper edge cutout portion 23. In other words, the lowermost end 17L in the upper edge portion of the first support portion 17 is disposed at a position lower than the uppermost end 18U in the upper edge portion of the second support portion 18. The lowermost end 17L of the upper edge of the first support 17 is located higher than the lower end (the height at which the backrest 16 reaches the maximum width) of the upper curved edge 22 (the upper end side support region 21). The lower end of the upper curved edge 22 is at a height at which the backrest portion 16 reaches the maximum width.

As shown in fig. 2, the width dimension of the backrest portion 16 is maximized at the upper end of the lower end side support region 20 (the lower end of the upper side bent edge portion 22). The maximum width dimension of the backrest portion 16 is set to be slightly smaller than the maximum width dimension of the seat portion 11. The width dimension of the backrest portion 16 is minimized at a lower end portion 16L (i.e., a rear end portion of the seat portion 11) of the backrest portion 16 (lower end side support region 20). The interval (width dimension) between the upper ends of the left and right upper bent edge portions 22 is smaller than the maximum width dimension of the backrest portion 16. The height dimension of the backrest portion 16 is set to be larger than the front-rear dimension of the seat portion 11.

As shown in fig. 2 and 3, the support surface 19 is composed of a first support surface 24 constituting the first support portion 17 and a pair of right and left symmetrical second support surfaces 28 constituting the second support portion 18. The first support surface 24 is disposed at the center in the lateral direction of the support surface 19, and has a substantially square shape in a vertical length as a whole. As shown in fig. 4, the upper end portion of the first support surface 24 is a first upper curved surface 25 that is curved so as to bulge obliquely upward and forward and to tilt obliquely upward and rearward.

As shown in fig. 4, the lower end 24L of the first support surface 24 is smoothly connected to the rear end of the seat portion 11 curved upward in the rearward direction. The region below the first upper curved surface 25 of the first support surface 24 is a first receiving surface 27 that is substantially planar. The first receiving surface 27 is oriented substantially along the vertical direction in the state where the posture holder 10 is being used. The up-down dimension of the first receiving surface 27 is approximately 1/2 of the entire height dimension of the first supporting surface 24.

A pair of right and left second support surfaces 28 are arranged on both right and left sides of the first support surface 24 in the support surface 19. The second support surface 28 is formed to extend obliquely forward from the left and right side edge portions of the first support surface 24. The front edge of the second support surface 28 is curved so as to bulge forward. That is, the dimension of the second support surface 28 in the front-rear direction (the dimension extending from the side edge portion of the first support surface 24) increases upward in the upper end side support region 21 of the second support surface 28, and decreases downward in the lower end side support region 20 of the second support surface 28.

The region of the second support surface 28 that is adjacent to the first support surface 24 in the left-right direction becomes a second receiving surface 29. The second receiving surface 29 is substantially planar and substantially parallel to the extending direction of the second support portion 18. The peripheral edge portion of the second support surface 28 surrounding the second receiving surface 29 from above, from the front and from below is curved so as to bulge inwardly in the obliquely front direction and to tilt obliquely rearward.

The upper end of the second support surface 28 is a second upper curved surface 30 that is curved so as to bulge obliquely upward and forward and to tilt obliquely upward and rearward. The left and right second upper curved surfaces 30 are smoothly connected to the left and right side portions of the first upper curved surface 25. The lower end portion of the second support surface 28 is a second lower curved surface 31 that is curved so as to bulge obliquely downward and forward.

As shown in fig. 3 and 11, a pair of left and right regions of the support surface 19 connecting the left and right side edges of the first support surface 24 and the second receiving surface 29 of the second support surface 28 are arc-shaped concave connecting surfaces 32 in a plan view. The pair of linking surfaces 32 are bilaterally symmetrical and extend vertically in a slender manner. In a plan view, the curvature of the first support surface 24 (first receiving surface 27) and the curvature of the second support surface 28 (second receiving surface 29) are small values near zero, whereas the curvature of the linking surface 32 is large. The first support surface 24, the left and right second support surfaces 28, and the left and right linking surfaces 32 define a substantially trapezoidal holding space 33 that is open toward the front in front of the backrest portion 16.

The first receiving surface 27 of the first support portion 17 is a region of the first support surface 24 that may be touched by a central portion of the back 52 of the seated person 50 in the lateral direction when seated. The second receiving surface 29 of the second support portion 18 is a region of the second support surface 28 that may be touched by both left and right side portions of the back 52 of the occupant 50 when seated. The uppermost position of the first receiving surface 27 is set at a position lower than the uppermost position of the second receiving surface 29. The first receiving surface 27 is sandwiched between a pair of second receiving surfaces 29 at a position in the left-right direction. Thus, the posture holder 10 can support the back 52 of the occupant 50 at 3 positions by the 1 first receiving surface 27 and the pair of right and left second receiving surfaces 29. The receiving surfaces 27, 29 of the 3 parts have a height difference, and are positioned in a relationship such that they are spaced apart from each other in the left-right direction and are spaced apart from each other in the front-rear direction.

As shown in fig. 12, the posture holder 10 is constituted by a housing member 34, a cushion material 39, and a wrapping cloth 40 in terms of its component configuration. The case member 34 is made of a hard synthetic resin, and is a plate-like single member having a fixed thickness over the entire area. The case member 34 is formed in a shape bent in a substantially L-shape in side view. The housing member 34 is composed of a seat portion forming plate portion 35 that forms the seat portion 11 and a backrest portion forming plate portion 36 that forms the backrest portion 16. The seat portion forming plate portion 35 has substantially the same shape as the seat portion 11, and is formed of a plurality of curved plate portions curved with different curvatures. The backrest portion forming plate portion 36 is formed to be raised upward from the rear end portion of the seat portion forming plate portion 35, and is composed of a first support plate portion 37 constituting the first support portion 17 and a pair of right and left symmetrical second support plate portions 38 constituting the second support portion 18.

The shape of the first support plate 37 is substantially the same as the first support 17 and the first support surface 24. The height region of the first support plate portion 37 corresponding to the first receiving surface 27 has a shape curved so as to bulge forward as a whole in a side view, and is slightly inclined forward from the vertical direction in a state where the posture holder 10 is placed on a horizontal surface. Further, the region of the first support plate portion 37 corresponding to the first upper curved surface 25 is curved so as to tilt obliquely upward and rearward. The region of the first support plate portion 37 corresponding to the first lower bent portion 26 is curved so as to be inclined downward and to bulge obliquely downward and rearward.

The pair of second support plate sections 38 extend obliquely forward from the left and right side edges of the first support plate section 37 in a substantially straight line, and are cantilevered so as to extend forward with a left-right spacing therebetween. The shape of the second support plate portion 38 is substantially the same as the second support portion 18 and the second support surface 28. The region of the second support plate portion 38 corresponding to the second receiving surface 29 is substantially flat, and the peripheral edge portion of the second support plate portion 38 is curved so as to tilt obliquely rearward.

As shown in fig. 4, the lower end 36L of the backrest portion forming plate portion 36 is connected to the rear end of the seat portion forming plate portion 35, but only the first support plate portion 37 is formed at the lower end 36L of the backrest portion forming plate portion 36. That is, although the first support plate portion 37 is directly connected to the seat constituting plate portion 35, the second support plate portion 38 is not directly connected to the seat constituting plate portion 35, but is connected to the seat constituting plate portion 35 via the first support plate portion 37.

The housing member 34 maintains the overall shape of the posture-holder 10, and has rigidity (shape-retainability) that can stably maintain the posture of the occupant 50. However, when a static load due to the weight of the sitting person 50, a dynamic load due to the sitting posture change of the sitting person 50, or the like is received, the sitting posture can be elastically deformed to such an extent that the sitting posture is not affected. Specifically, the second support plate portion 38 is elastically displaceable relative to the first support plate portion 37 so as to spread in the left-right direction with the left and right side edge portions of the first support plate portion 37 as substantially fulcrums.

When the static load or the dynamic load is applied, the backrest portion forming plate portion 36 (backrest portion 16) is elastically and relatively displaceable with respect to the seat portion forming plate portion 35 (seat portion 11) so that the lower end portion 36L of the backrest portion forming plate portion 36 (rear end portion of the seat portion forming plate portion 35) is inclined in the front-rear direction with the substantially pivot point. At this time, the elastic deformation amount of the back-rest section constituting plate section 36 (stress generated in the back-rest section constituting plate section 36) is maximized at the lower end section 36L, which is a substantial fulcrum of the elastic displacement, but at least the lower end side support region 20 of the first support plate section 37 is also elastically deformed. The elastic deformation of the lower end side support region 20 of the first support plate portion 37 is preferably performed as a means for avoiding stress concentration on the lower end portion 36L of the backrest portion constituting plate portion 36.

However, the second support plate portions 38 protruding from the left and right side edges of the first support plate portion 37 function as reinforcing ribs that resist elastic deformation of the first support plate portion 37. Accordingly, as shown in fig. 8 to 10, the protruding dimension of the first support plate portion 37 in the lower end side region of the second support plate portion 38 is set so as to gradually decrease downward. Accordingly, when the backrest portion forming plate portion 36 is elastically displaced in the front-rear direction with respect to the seat portion forming plate portion 35, the lower end side region of the first support plate portion 37 is also elastically deformed by bending. In embodiment 1, the lower end region of the second support plate portion 38 is defined as a region from the lower end portion 38L of the second support plate portion 38 to a height of at least about 1/3.

The cushion material 39 is mounted in a laminated manner on a surface of the case member 34 (an upper surface of a portion constituting the seat portion 11 and a front surface of a portion constituting the backrest portion 16) opposite to the occupant 50. The cushion material 39 is made of, for example, urethane foam, and is a member for avoiding uncomfortable feeling caused by the buttocks 51 and the back 52 of the sitting person 50 hitting the relatively hard cover member 34. The thickness of the portion of the cushion material 39 corresponding to the first receiving surface 27 is not constant in the vertical direction, and the thickness varies so as to gradually become thicker downward. Thus, when the posture holder 10 is placed on the horizontal surface, the first receiving surface 27 of the first support surface 24 is set in a direction to rise substantially vertically.

The wrapping cloth 40 is made of cloth and covers the entirety of the outer surface of the housing member 34 (the lower surface of the portion constituting the seat portion 11 and the rear surface of the portion constituting the backrest portion 16) and the surface of the cushion material 39 that faces the occupant 50 (the upper surface of the portion constituting the seat portion 11 and the front surface of the portion constituting the backrest portion 16). When the case member 34 is elastically deformed, the cushion material 39 and the wrapping cloth 40 are flexibly deformed accordingly.

The posture holder 10 may be used in a state of being directly placed on the ground (not shown) or in a state of being placed on the chair 53. In fig. 12, the chair is shown in a state of being placed on the chair for use. When the sitting person 50 sits on the posture holder 10, the buttocks 51 are supported by the seat 11 from below, the trunk portion of the upper body is accommodated in the holding space 33, and the back 52 is supported by the backrest 16 from behind. At this time, a portion corresponding to the lower portion of the thoracic vertebrae among the left and right direction central portions of the spine 52 is abutted against the first support surface 24, and the left and right side portions of the spine 52 are abutted against the left and right second support surfaces 28.

At this time, the contact point on the second support surface 28 is a position higher than the contact point on the first support surface 24, and is a position further forward than the contact point on the first support surface 24. That is, a plurality of portions of the back 52 having different positions in the three-dimensional direction are supported. In addition, when the sitting person 50 is an average adult, the contact position on the second support surface 28 is the back surface side of the rib, and is a height lower than the scapula.

The posture holder 10 of this embodiment 1 includes: a seat portion 11 that supports buttocks 51 of a seated person 50 from below; and a backrest portion 16 that is raised from the rear end portion of the seat portion 11 and supports the upper body of the seated person 50 from the back 52 side. The backrest portion 16 is configured to include a first support portion 17 that is in contact with a central portion of the back 52 of the seated person 50 in the lateral direction, and a pair of second support portions 18 that are disposed on both left and right sides of the first support portion 17 and are in contact with both left and right sides of the back 52 of the seated person 50.

The first support portion 17 supports a relatively lower portion of the central portion of the back 52 of the occupant 50 from behind, and the pair of right and left second support portions 18 supports a portion of the back 52, which is higher than the first support portion 17, from diagonally behind in a sandwiching manner. Thus, the occupant 50 sits with relatively lower portions of the central portion of the back 52 attached to the first support portion 17 and relatively higher portions of the left and right side portions of the back 52 attached to the second support portion 18. The sitting person 50 can support the back 52 at 3 positions spaced apart in the left-right direction and having a height difference by the 3 support portions 17, 18, and therefore, can be restrained from being in a posture of tilting the upper half body in the left-right direction or in a posture of twisting the upper half body in the left-right direction. Thus, the posture holder 10 of the present embodiment 1 can hold the upper body of the seated person 50 in a correct posture.

Further, the first support portion 17 supports a relatively lower portion (whole or part of a range from an upper portion of the lumbar vertebra to a lower portion of the thoracic vertebra) in the back 52 of the occupant 50, and the second support portion 18 supports a relatively higher portion (whole or part of a portion corresponding to a middle height from the lower portion of the thoracic vertebra to the thoracic vertebra in the rib back) of the back 52, and therefore, the back 52 is supported at a plurality of portions having a height difference when the occupant 50 presses the body weight against the backrest portion 16. Thus, the upper body of the seated person 50 can be maintained in a correct posture in which the spine draws an appropriate curve in side view. Here, the correct posture refers to a posture in which the thoracic vertebrae are curved so as to bulge rearward, the lumbar vertebrae are curved so as to bulge forward, and the sacrum to coccyx are curved so as to bulge rearward.

In addition, when the height of the upper end of the first support portion 17 is made equal to the height of the upper end of the second support portion 18, there is a concern that the thoracic vertebrae portion of the back 52, which is curved to bulge rearward, will collide with the upper end of the first support portion 17, and it will be difficult for the spine to draw an appropriate curve. As a countermeasure, in the posture holder 10 of this embodiment 1, the upper edge notch portion 23 is formed at the upper end edge of the backrest portion 16 so that the upper end of the first support portion 17 is lower than the upper end of the second support portion 18, but if the upper edge notch portion 23 is formed, a space is formed above the closest portion of the first support portion 17 (i.e., between the upper end portions of the left and right two second support portions 18), and therefore, the ridge 52 cannot be supported any more above the closest portion of the first support portion 17. Therefore, there is a concern that the upper portion of the upper body of the occupant 50 above the first support portion 17 (the relatively low portion of the back 52) is bent rearward, but since the upper body of the occupant 50 is supported by the second support portion 18 on the left and right sides above the first support portion 17, the occupant 50 can sit in a relaxed state with the chest opened moderately.

In the sitting state, the second support portion 18 is elastically displaced obliquely rearward by receiving the pressing force from the upper body of the occupant 50, and therefore, the occupant strongly receives the pressing force on the left and right sides of the central portion of the back 52 by the elastic restoring force of the second support portion 18 (second support plate portion 38). Therefore, the upper body of the seated person 50 can be restrained from being in a laterally tilted posture or a laterally twisted posture.

Further, since the second upper curved surface 30 that is curved so as to tilt obliquely rearward as it goes upward is formed at the upper end portion of the second support portion 18, when the upper body of the occupant 50 abuts against the backrest portion 16, the upper end edge of the second support portion 18 does not sink into the body of the occupant 50, and the occupant 50 can sit deep on the seat portion 11. Further, by sitting deep, the left and right side portions of the back 52 are reliably pressed by the second support portions 18, so that the upper body can be reliably prevented from twisting left and right. Further, the upper end portion of the second support portion 18 is not caught in the body of the occupant 50, and the upper portion of the back 52 can be bent backward moderately, so that the occupant 50 can be held in a correct posture.

Further, the posture holder 10 is provided with a housing member 34 to hold its shape. The case member 34 includes: a seat portion forming plate portion 35 that forms the seat portion 11; and a backrest portion constituting plate portion 36 constituting the backrest portion 16. The backrest portion forming plate portion 36 is connected to the seat portion forming plate portion 35 so as to be elastically and relatively displaceable with a lower end portion 36L of the backrest portion forming plate portion 36 being a substantially fulcrum. Therefore, when the occupant 50 presses the upper body against the backrest 16 with force, the backrest 16 is elastically displaced relative to the seat 11 rearward with the lower end 36L thereof as a substantially fulcrum.

At this time, if stress concentrates on the lower end 36L of the backrest portion structural plate portion 36, which is a fulcrum of the relative elastic displacement, stress concentration repeatedly occurs to progress the degradation, and durability may be lowered. As means for avoiding stress concentration on the lower end 36L of the backrest portion forming plate portion 36, it is preferable to elastically deform not only the lower end 36L of the backrest portion forming plate portion 36 but also at least the lower end side region of the backrest portion forming plate portion 36.

However, the backrest portion forming plate portion 36 is constituted by a first support plate portion 37 constituting the first support portion 17 and a pair of right and left second support plate portions 38 protruding obliquely forward from both right and left side edges of the first support plate portion 37 to constitute the second support portion 18, and therefore is difficult to deform. Therefore, the protruding dimension of the first support plate portion 37 in the lower end side region of the second support plate portion 38 is gradually reduced downward. Accordingly, since the backrest portion forming plate portion 36 is elastically deformed not only at the lower end portion 36L but also at the lower end side region, stress concentration at the lower end portion 36L of the backrest portion forming plate portion 36 can be prevented. Further, the upper end side region of the backrest portion constituting plate portion 36 has higher flexural rigidity and is less likely to elastically deform than the lower end side region, and therefore the upper body of the seated person 50 can be stably held.

Further, the first support surface 24 of the first support portion 17 facing the back 52 and the second support surface 28 of the second support portion 18 facing the back 52 are connected via the pair of left and right connecting surfaces 32, and the curvature of the first support surface 24 and the curvature of the second support surface 28 are set smaller than the curvature of the connecting surfaces 32 in a plan view. With this configuration, the back 52 does not contact the connecting surface 32 having a large curvature, and therefore the upper body of the seated person 50 can be stably supported at 3 positions of the first support surface 24 and the pair of left and right second support surfaces 28.

< other embodiments >

The present invention is not limited to the embodiments described above and illustrated in the drawings, and, for example, the following embodiments are included in the technical scope of the present invention.

(1) In the posture holder of the above embodiment, the seat portion and the backrest portion are integrally formed, but the posture holder may be configured in such a manner that the seat portion and the backrest portion of the independent member are assembled.

(2) In the above embodiment, the upper end portion of the second support portion is curved so as to tilt obliquely rearward as going upward, but the upper end portion of the second support portion may be curved.

(3) The backrest portion forming plate portion of the above embodiment is formed by integrating the first support plate portion and the second support plate portion, but the backrest portion forming plate portion may be formed by assembling the first support plate portion and the second support plate portion of separate members.

(4) In the above embodiment, the protruding dimension of the first support plate section in the lower end side region of the second support plate section is gradually smaller downward, but the protruding dimension of the first support plate section in the lower end side region of the second support plate section may be substantially fixed in the up-down direction.

(5) In the above embodiment, the seat portion and the backrest portion are elastically displaced relative to each other, but the seat portion and the backrest portion may not be displaced relative to each other.

(6) In the above embodiment, the first support surface and the second support surface are connected via the connecting surface having a large curvature, and the back of the seated person is supported at 3 positions spaced apart in the left-right direction, but the present invention is not limited thereto, and the curvature of the connecting surface may be made smaller than that of embodiment 1, so that the back is supported by a region continuous in the left-right direction from the second support surface on the left side to the second support surface on the right side. In this case, too, the upper body of the seated person can be restrained from being in a tilted posture or a twisted posture.

(7) In the above embodiment, the upper edge portion of the first support portion is formed with the upper edge notch portion so that a space is left in the vicinity of the upper side of the first support portion (between the upper end portions of the left and right second support portions), but the upper edge notch portion may not be formed and the height of the upper end of the first support portion may be substantially the same as the height of the upper end of the second support portion. Even if the upper edge portion of the backrest portion is a height fixed in a wide range, if the backward tilting degree of the region corresponding to the upper end portion of the first support portion in the upper edge portion of the backrest portion is made deeper than the upper end portion of the second support portion, the lateral central portion of the backrest portion can be prevented from being strongly touched to the upper edge portion of the backrest portion when the backrest is bent backward.

Claims

1. A posture holder, characterized by comprising:

a seat;

a backrest portion that is raised from a rear end portion of the seat portion;

a first support portion that constitutes the backrest portion and that abuts against a back of a seated person; and

a pair of second supporting parts which form the backrest part and extend obliquely forward from the left and right side edges of the first supporting part,

the first support portion supports a central portion of a back of a seated person from behind,

the pair of second support portions support left and right side edge portions of the back of the seated person from diagonally behind.

2. The posture holder of claim 1, characterized in that,

the pair of second support portions support left and right side edge portions of the back of the seated person in a sandwich manner.

3. The posture holder of claim 1, characterized in that,

the pair of second support portions support a portion of the back of the seated person above a portion supported by the first support portion.

4. The posture holder of claim 1, characterized in that,

the first support portion supports the whole or a part of the range from the upper portion of the lumbar vertebra to the lower portion of the thoracic vertebra in the back of the seated person,

the pair of second support portions support, in whole or in part, a portion of a rib back of a seated person, the portion corresponding to an intermediate height from a lower portion of the thoracic vertebrae to the thoracic vertebrae.

5. The posture holder of claim 1, characterized in that,

the backrest portion forming plate portion is formed as a single member by connecting the first support plate portion forming the first support portion and the pair of second support plate portions forming the pair of second support portions to each other,

the second support plate portion functions as a reinforcing rib against elastic deformation of the first support plate portion.

6. The posture holder of claim 5, characterized in that,

the backrest portion forming plate portion and the seat portion forming plate portion that form the seat portion are connected to each other so as to be elastically and relatively displaceable with a lower end portion of the backrest portion forming plate portion being a substantially fulcrum.

7. The posture holder of claim 5, characterized in that,

a pair of second support plate sections protruding obliquely forward from left and right side edges of the first support plate section,

the protruding dimension of the first support plate section in the lower end side region of the second support plate section gradually decreases downward.

8. The posture holder of claim 1, characterized in that,

the pair of second support portions can be elastically displaced obliquely rearward by receiving a pressing force from a seated person.

9. The posture holder of claim 1, characterized in that,

a first support surface of the first support portion facing the back and a second support surface of the second support portion facing the back are connected via a pair of left and right connecting surfaces,

the curvature of the first support surface and the curvature of the second support surface are smaller than the curvature of the linking surface in a plan view.

10. The posture holder of claim 1, characterized in that,

the upper end portions of the pair of second support portions are curved so as to tilt obliquely rearward as going upward.

11. The posture holder of claim 1, characterized in that,

the upper end portion of the first support portion is curved so as to tilt obliquely upward and rearward.

12. The posture holder of claim 1, characterized in that,

the lowermost end portion of the upper edge portions of the first support portions is disposed at a position lower than the uppermost end portion of the upper edge portions of the pair of second support portions.

13. The posture holder of claim 12, characterized in that,

the upper edge portion formed by the outer peripheral edge of the upper end side support region above the lower end side support region in the backrest portion has a shape in which the central portion in the lateral direction of the upper edge portion is formed in an obtuse-angled concave shape.