CN110077300B

CN110077300B - Seat cushion and chair

Info

Publication number: CN110077300B
Application number: CN201910196894.9A
Authority: CN
Inventors: 村口健一; 野村寿子
Original assignee: P A S Co ltd
Current assignee: P A S Co ltd; P.A.S.股份有限公司
Priority date: 2013-12-03
Filing date: 2013-12-03
Publication date: 2021-09-10
Anticipated expiration: 2033-12-03
Also published as: CN110077300A; CN104670054A

Abstract

The invention provides a seat cushion and a chair, which are not easy to press the buttocks of a seated person, easy to maintain the correct posture and easy to breathe the seated person. The seat cushion of the present invention includes a seat portion and a back portion. Two parts of a seat part corresponding to the ischia of a seated person are curved into a concave shape in the horizontal direction, and the vertical section in the horizontal direction is inclined to the surface side along the backward side.

Description

Seat cushion and chair

The application is a divisional application of patent application with application number 201310642031.2, which is filed on 2013, 12 and 3 months and has the invention name of 'chair cushion and chair'.

Technical Field

The invention relates to a chair cushion and a chair.

Background

Seat cushions are used, for example, in chairs such as office chairs. As a cushion used in the office chair and the like, a cushion which can be placed on a seat surface of the chair and a back cushion which is attached to a backrest portion of the chair and abuts against a back of a seated person are known.

However, in the seat cushion and the back cushion, since a part of the buttocks of the seated person receives the body weight, the buttocks are pressed or the posture is easily deformed. Further, the seated person receives a feeling that the chest and abdomen are compressed because of the back cushion, resulting in difficulty in breathing.

Further, as a seat holding device mainly applied to a seat of an automobile driver's seat, a seat holding device disclosed in japanese patent laid-open publication No. 2012-46005 has been known, which has a pair of iliac supporting projections on a back portion abutting on a back of a seated person, and abuts on the iliac projections of the seated person in the vicinity of the abutment of the iliac of the seated person. The seat holding device prevents a seated person from diving (a state in which the hip is displaced forward and the pelvis is tilted backward) during driving by the iliac supporting projections, so that the seated person can easily maintain a posture and breathe comfortably. However, as described above, the seat holding device is mainly applied to a seat of a driver's seat of an automobile, but is not necessarily applied to a structure of a chair such as an office chair.

Patent document 1: japanese patent laid-open publication No. 2012-46005

Disclosure of Invention

In view of the above circumstances, an object of the present invention is to provide a seat cushion and a chair that are not likely to press the buttocks of a seated person, are easy to maintain a correct posture, and are easy for the seated person to breathe.

In order to solve the above-mentioned problems, a seat cushion according to the present invention includes a seat section to which buttocks of a seated person are brought into contact and a back section to which a back of the seated person is brought into contact, wherein two surfaces of the seat section to which ischia bones of the seated person are brought into contact are three-dimensionally curved surfaces which are curved in a concave shape in a right-left direction vertical section and inclined toward a front surface side along a rear side in the front-rear direction vertical section, the seat section includes at least a ridge section formed from a central portion toward a front side and a pair of concave sections formed on right and left sides of the ridge section, surfaces of the ridge section and the pair of concave sections are continuous in the right-left direction vertical section, and in order to allow the seated person to easily move legs, surfaces of the concave sections are inclined so that a lowermost point of the right-left direction vertical section is located outward from the rear side toward the front side and inclined toward the front side, and thereafter inclined to the back side further forward, a surface of a portion of the back portion corresponding to an upper iliac edge, against which an ilia of the seated person abuts, being curved in a concave shape as a whole in a lateral cross section, a surface of a portion of the back portion corresponding to a lower rib, against which a lower rib of the seated person abuts, being curved in a concave shape as a whole in a lateral cross section, being a three-dimensional curved surface which is curved in a concave shape as a whole in a lateral cross section and inclined to the back side along the upward side in a vertical longitudinal section, a lateral curvature radius of the three-dimensional curved surface of the upper portion surface being larger than a lateral curvature radius of the surface of the portion corresponding to the lower rib, the back portion being shaped to wrap the back of the seated person and be supported from below, the seat portion and the back portion being formed integrally, and a notch part with a narrow width in the left-right direction is arranged at the continuously arranged part, and the surface of the seat part and the back part is a three-dimensional curved surface which is continuously concave as a whole from the part corresponding to the ischia to the part corresponding to the upper edge of the ilium.

The "front-rear direction", "up-down direction" and "left-right direction" refer to directions seen from a seated person when the seated person sits down with the back facing the back, respectively. That is, the "front-rear direction" refers to the direction in which the thighs and buttocks of the seated person extend. The "up-down direction" refers to the extending direction of the back and hip of the seated person. The "left-right direction" refers to a direction perpendicular to the front-back direction and the up-down direction.

The seat portion of the seat cushion is used by being placed on the seat surface of the chair, and the surface of the seat portion corresponding to the ischial portion is a three-dimensional curved surface which is curved in a concave shape in a longitudinal section in the left-right direction and is inclined toward the front surface side along the rear side in the longitudinal section in the front-rear direction. The upper iliac edges and lower ribs of the seated person are located exactly on the back at locations corresponding to the upper iliac edges and at locations corresponding to the lower ribs. Further, the surface of the portion corresponding to the upper iliac edge is curved in a concave shape as a whole in the lateral cross section, the surface of the portion corresponding to the lower ribs is curved in a concave shape as a whole in the lateral cross section, and the surface of the portion located above the portion corresponding to the lower ribs is a three-dimensional curved surface which is curved in a concave shape as a whole in the lateral cross section and is inclined toward the back surface side as going upward in the vertical cross section, so that the back of the seated person can be wrapped with the back and supported from below. Therefore, the seat cushion is not easy to press the buttocks of a seated person, and is easy to maintain a correct posture and breathe.

In the seat cushion, a surface of a portion corresponding to the ischia is preferably inclined toward the front surface side along the front side in a longitudinal section in the front-rear direction. Therefore, the ischia of the hip of the seated person can be easily and accurately accommodated in the ischia-equivalent portion.

In the seat cushion, it is preferable that the seat portion includes a ridge portion formed at least from the center portion to the front and a pair of concave portions formed on both left and right sides of the ridge portion, and surfaces of the ridge portion and the pair of concave portions are continuous in a left-right direction longitudinal section. Therefore, the pair of thighs of the seated person are accurately fitted into the pair of concave portions, and the seated person can easily maintain the posture by positioning the thighs of the seated person at accurate positions.

The seat cushion may be formed by a seat portion and a back portion separately attached to a chair, for example, but in the seat cushion, the seat portion and the back portion are preferably formed integrally. Therefore, the chair can be easily mounted on the chair, and each part can be easily positioned at a correct position when mounted.

In the seat cushion, it is preferable that a surface of the seat portion from the portion corresponding to the ischia to a rear portion of the back portion is a three-dimensional curved surface which is curved in a concave shape in a longitudinal cross section in the left-right direction and is continuous from the surface of the portion corresponding to the ischia to a surface of the back portion in a longitudinal cross section in the front-rear direction. Therefore, the hip portion located more rearward than the ischial bones of the seated person is wrapped and supported by the rear portion of the seat portion, and the seated person can be more easily maintained in a correct posture.

In the seat cushion, a surface of a lower portion of the back portion located below a position corresponding to an upper edge of the ilium is preferably a three-dimensional curved surface that is curved in a concave shape in a transverse cross section in the left-right direction and is continuous with a rear portion of the seat portion in a longitudinal cross section in the front-rear direction. Therefore, the lower portion of the back can wrap and support the buttocks on the back side of the seated person, and the seated person can be more easily maintained in a correct posture.

In the seat cushion, it is preferable that an angle formed by the seat portion and the back portion when viewed from the side is 90 ° or more and 110 ° or less. Therefore, the chair can be easily and reliably placed on a chair such as an office chair.

In order to solve the above-mentioned problems, the chair of the present invention comprises a seat section to which buttocks of a seated person are brought into contact and a back section to which a back of the seated person is brought into contact, wherein two surfaces of the seat section to which ischia of the seated person is brought into contact are three-dimensionally curved surfaces which are curved in a concave shape in a right-left direction vertical section and inclined toward a front surface side along a rear side in a front-rear direction vertical section, the seat section includes at least a ridge section formed from a central portion toward a front side and a pair of concave sections formed on right and left sides of the ridge section, surfaces of the ridge section and the pair of concave sections are continuous in the right-left direction vertical section, and in order to allow the seated person to easily move legs, surfaces of the concave sections are inclined so that a lowermost point of the right-left direction vertical section is located outward from the rear side toward the front side and inclined toward the front side from the positions corresponding to the front sides, and thereafter inclined to the back side further forward, a surface of a portion of the back portion corresponding to an upper iliac edge, against which an ilia of the seated person abuts, being curved in a concave shape as a whole in a lateral cross section, a surface of a portion of the back portion corresponding to a lower rib, against which a lower rib of the seated person abuts, being curved in a concave shape as a whole in a lateral cross section, being a three-dimensional curved surface which is curved in a concave shape as a whole in a lateral cross section and inclined to the back side along the upward side in a vertical longitudinal section, a lateral curvature radius of the three-dimensional curved surface of the upper portion surface being larger than a lateral curvature radius of the surface of the portion corresponding to the lower rib, the back portion being shaped to wrap the back of the seated person and be supported from below, the seat portion and the back portion being formed integrally, and a notch part with a narrow width in the left-right direction is arranged at the continuously arranged part, and the surface of the seat part and the back part is a three-dimensional curved surface which is continuously concave as a whole from the part corresponding to the ischia to the part corresponding to the upper edge of the ilium.

Since the surface of the seat corresponding to the ischial parts is a three-dimensional curved surface which is curved in a concave shape in a horizontal longitudinal section and is inclined toward the front surface side with the backward side in a forward and backward longitudinal section, the ischial parts of the buttocks of the seated person can be easily and accurately accommodated in the ischial parts of the seat after the seated person is seated on the chair. The upper iliac edges and lower ribs of the seated person are located exactly on the back at locations corresponding to the upper iliac edges and at locations corresponding to the lower ribs. Further, the surface of the portion corresponding to the upper iliac edge is curved in a concave shape as a whole in the lateral cross section, the surface of the portion corresponding to the lower ribs is curved in a concave shape as a whole in the lateral cross section, and the surface of the portion located above the portion corresponding to the lower ribs is a three-dimensional curved surface which is curved in a concave shape as a whole in the lateral cross section and is inclined toward the back surface side as going upward in the vertical cross section, so that the back of the seated person can be wrapped with the back and supported from below. Therefore, the chair is not easy to press the buttocks of a seated person, is easy to maintain a correct posture, and is easy to breathe.

As described above, the seat cushion and the seat according to the present invention do not easily press the buttocks of the seated person, make the seated person easily maintain a correct posture, and make the seated person easily breathe.

Drawings

Fig. 1 is a schematic perspective view of a seat cushion according to an embodiment of the present invention.

Fig. 2 is a schematic front view of the seat cushion of fig. 1.

Fig. 3 is a schematic plan view of the seat cushion of fig. 1.

Fig. 4 is a schematic side view of the seat cushion of fig. 1.

Fig. 5 is a sectional view taken along line I-I in fig. 3.

Fig. 6 is a sectional view taken along line II-II in fig. 3.

Fig. 7 is a sectional view taken along line III-III of fig. 4.

Fig. 8 is a sectional view taken along line IV-IV in fig. 4.

Fig. 9 is a cross-sectional view taken along line V-V of fig. 4.

Fig. 10 is a sectional view taken along line VI-VI in fig. 3.

Fig. 11 is a sectional view taken along line VII-VII in fig. 4.

Fig. 12 is a sectional view taken along line VIII-VIII in fig. 4.

Fig. 13 is a cross-sectional view taken along line IX-IX in fig. 4.

Fig. 14 is a cross-sectional view taken along line X-X in fig. 4.

Description of the reference numerals

1 cushion body

1a notch part

10 seat part

11 parts corresponding to ischia

13 convex strip part

15 concave strip part

17 outer convex strip

30 back

Point O

Angle alpha

Detailed Description

Hereinafter, a seat cushion according to an embodiment of the present invention will be described, and the seat cushion according to the embodiment is applied to a chair having a seat surface and a backrest portion.

The seat cushion has a cushion body 1 and a cover (not shown) covering the cushion body 1. As shown in fig. 1, the cushion body 1 includes: a seat 10 placed on a seat surface of the chair, and against which a hip of a seated person abuts; the back 30 is a portion against which the back of the seated person abuts. The seat portion 10 and the back portion 30 are formed integrally. The cushion body 1 is made of an elastic (cushioning) member, specifically, a foamed resin such as a urethane foam. The cushion body 1 is constituted by an elastic member, so that the angle α of both the seat portion 10 and the back portion 30, which are integrally formed as described above, as viewed from the side can be changed. The cushion can be accurately placed on the chair by deforming the cushion body 1 according to the angle formed by the seat surface and the backrest portion of the chair by using the structure.

The cushion body 1 has a cutout 1a with a narrow center in a width in the left-right direction at a portion where the seat portion 10 and the back portion 30 are continuously provided. Therefore, the cushion body 1 can be easily deformed in a direction in which the angle α formed by the seat portion 10 and the back portion 30 changes.

The cushion body 1 may be formed by connecting the seat portion 10 and the back portion after the seat portion 10 and the back portion 30 are formed, respectively. However, it is preferable that the back part 30 and the seat part 10 are integrally formed.

The lateral width W1 of the seat 10 is 430mm, and the lateral width W1 of the seat 10 is preferably 300mm to 550 mm. The lower limit of the lateral width W1 is more preferably 350mm, still more preferably 400 mm. The upper limit of the lateral width W1 is more preferably 500mm, still more preferably 450 mm.

The longitudinal width L1 of the seat 10 is 414mm, and the longitudinal width L1 of the seat 10 is preferably 300mm to 550 mm. The lower limit of the longitudinal width L1 is more preferably 350mm, and still more preferably 400 mm. The upper limit of the longitudinal width L1 is more preferably 500mm, still more preferably 450 mm.

The height H1 (height from the bottom surface of the seat 10) of the back 30 is 366mm, and the height H1 of the back 30 is preferably 280mm to 500 mm. The lower limit of the height H1 is more preferably 300mm, and still more preferably 340 mm. The upper limit of the height H1 is more preferably 450mm, and still more preferably 400 mm.

The cushion is adapted to be mounted on a chair for an adult by making the lateral width W1, the longitudinal width L1, and the height H1 of the back portion 30 of the seat 10 within the ranges.

In the case of a cushion for children, the lateral width W1, the longitudinal width L1, and the height H1 of the back portion 30 of the seat portion 10 are preferably in the following ranges.

The lateral width W1 of the seat portion 10 is preferably 200mm or more and 450mm or less. The lower limit of the lateral width W1 is more preferably 250mm, still more preferably 300mm, and the upper limit of the lateral width W1 is more preferably 400mm, still more preferably 350 mm.

The longitudinal width L1 of the seat portion 10 is preferably 200mm or more and 450mm or less. The lower limit of the longitudinal width L1 is more preferably 250mm, still more preferably 300mm, and the upper limit of the longitudinal width L1 is more preferably 400mm, still more preferably 350 mm.

The height H1 of the back 30 is preferably 180mm to 400 mm. The lower limit of the height H1 is more preferably 200mm, still more preferably 240mm, and the upper limit of the height H1 is more preferably 350mm, still more preferably 300 mm.

The bottom surface (inside surface) of the seat 10 is a flat surface. The back (inside) of the back 30 is planar. Therefore, when the seat is placed on the chair, the bottom surface of the seat 10 can be accurately placed on the seat surface of the chair in a state where the back surface of the back 30 abuts on the backrest portion of the chair.

The angle α formed by the seat portion 10 and the back portion 30 when viewed from the side is preferably 90 ° or more and 110 ° or less, and more preferably 100 ° or more and 105 ° or less. Since within said range it can be placed accurately and easily on an office chair. In the case of a cushion for children, the angle α is preferably around 90 ° (90 ° ± 5 °). The angle α formed by the seat portion 10 and the back portion 30 when viewed from the side is an angle in a normal state in which no external force acts on the cushion body 1.

The surfaces of the seat portion 10 and the back portion 30 are three-dimensionally curved surfaces, the shape of which will be described in detail below.

The surface of the seat 10 has two ischial equivalent portions 11 that are recessed, and the surface of the ischial equivalent portions 11 is curved in a concave shape. The surface of the portion 11 corresponding to the ischia is a three-dimensional curved surface which is curved in a concave shape in a horizontal longitudinal section and is inclined toward the front surface side with respect to the front and rear longitudinal sections. The portion 11 corresponding to the ischial bones is a portion against which the ischial bones of the seated person abut, and is a portion around a lowermost point O (a point closest to the back surface of the seat portion 10) in the surface of the seat portion 10 against which the hip portions of the seated person abut (a region around the lowermost point of 80mm (a region surrounded by a circle of a dashed-dotted line in fig. 3)).

The distance W2 between the centers O of the two ischial parts 11 is 108mm in the present embodiment. The distance W2 between the centers O of the two ischial parts 11 is preferably 70mm to 130 mm. The lower limit of the distance W2 between the centers O is more preferably 90mm, and the upper limit of the distance W2 between the centers O is more preferably 120 mm. When the distance W2 between the centers O is within the above range, the ischia of the seated person is accommodated in the portion 11 corresponding to the ischia in the case where the seated person is an adult.

In the case of the child mat, the distance W2 between the centers O of the two ischial parts 11 is preferably 70mm to 120 mm. The lower limit of the distance W2 between the centers O is more preferably 80mm, and the upper limit of the distance W2 between the centers O is more preferably 110 mm.

In the present embodiment, the thickness H2 (distance between the surface and the bottom of the center O) of the seat 10 at the center O of the ischial parts 11 is 9 mm.

The distance L2 from the center O of the ischial region 11 to the front end of the pad body 1 is 314mm in the present embodiment. The distance L2 from the center O of the ischial region 11 to the front end of the pad body 1 is preferably 280mm to 400 mm. The lower limit of the distance L2 is more preferably 300mm, and the upper limit of the distance L2 is more preferably 350 mm.

In the case of the cushion for children, the distance L2 from the center O of the portion 11 corresponding to the ischial bones to the front end of the cushion body 1 is preferably 230mm to 350 mm. The lower limit of the distance L2 is more preferably 250mm, and the upper limit of the distance L2 is more preferably 300 mm.

The front surface of the portion 11 corresponding to the ischia is greatly inclined toward the rear side of the center O of the portion 11 corresponding to the ischia than toward the front side thereof in the longitudinal section in the front-rear direction (see fig. 6).

Since the surfaces of the pair of portions 11 corresponding to the ischial bones of the seat portion 10 are curved in a concave shape as described above, the seat portion 10 has a portion higher than the portions 11 corresponding to the ischial bones between the portions 11 corresponding to the ischial bones positioned on the rear side in the front-rear direction (the center in the left-right direction) (see fig. 7), and the surface at the center in the front-rear direction is curved in a concave shape as a whole in a vertical cross section in the left-right direction (see fig. 8).

The seat 10 comprises: a raised strip portion 13 formed from the front to the rear and from the center to the front; a pair of concave portions 15 formed on both left and right sides of the convex portion 13. The surfaces of the ridges 13 and the pair of grooves 15 are continuous in a cross section in the left-right direction (see fig. 9). The parts 11 corresponding to the ischia are respectively positioned on virtual extension lines extending rearward of the pair of concave portions 15.

The surfaces of the concave portions 15 are inclined so that the lowest point of the horizontal longitudinal section is located outward from the rear side to the front side (see fig. 2). Therefore, the lowermost point of the tip ends of the concave portions 15 is located outside the right and left positions of the ischial portion 11. The surfaces of the concave portions 15 are inclined from the portion 11 corresponding to the ischia to the front side and then inclined to the back side (see fig. 10) further to the front side. Therefore, even in a state where the ischia bones are accommodated in the parts 11 corresponding to the ischia bones as described above, the seated person can easily move the legs when moving the legs.

The seat portion 10 has outer ridges 17 (see fig. 7 to 9) higher than other portions (for example, the ridges 13) at left and right edge portions (outer sides of the grooves 15). Therefore, the legs of the seated person are not easily moved outward.

The back portion 30 is curved in a concave shape in a left-right direction at a portion corresponding to an upper edge of an ilium and a portion corresponding to a lower rib.

The part corresponding to the upper iliac edge is a part against which the upper iliac edge of the seated person abuts. The portion corresponding to the upper iliac edge is, in the present embodiment, a position (cross-sectional position in fig. 11) distant from the center O of the portion corresponding to the ischial bones by 150mm (L3) in the direction extending from the center O to the back 30.

The distance L3 in the direction in which the center of the portion corresponding to the upper iliac edge extends from the center O of the portion corresponding to the ischial bones 11 toward the back 30 is preferably 120mm to 180 mm. The lower limit of the distance L3 is more preferably 140mm, and the upper limit of the distance L3 is more preferably 160 mm.

In the case of the cushion for children, the distance L3 to the center of the portion corresponding to the upper iliac edge is preferably 80mm to 120mm, the lower limit of the distance L3 is more preferably 90mm, and the upper limit of the distance L3 is more preferably 110 mm.

The region corresponding to the lower rib is a region against which the lower rib of the seated person abuts. Specifically, the portion corresponding to the lower ribs is, in the present embodiment, a position (cross-sectional position in fig. 12) which is a distance of 250mm (L4) in the direction extending from the center O of the portion corresponding to the ischial bones 11 to the back 30. The distance L4 in the direction in which the portion corresponding to the lower ribs extends from the center O of the portion corresponding to the ischial bones 11 toward the back 30 is preferably 220mm to 280 mm. The lower limit of the distance L4 is more preferably 240mm, and the upper limit of the distance L4 is more preferably 260 mm.

In the case of the cushion for children, the distance L4 to the portion corresponding to the lower rib is preferably 180mm or more and 240mm or less, the lower limit of the distance L4 is more preferably 200mm, and the upper limit of the distance L4 is more preferably 220 mm.

The surface of the portion located upward from the portion corresponding to the lower rib is curved in a concave shape as a whole in the lateral cross section, and is inclined toward the back side as it goes upward in the vertical cross section (see fig. 10). Therefore, the surface of the portion located above the portion corresponding to the lower rib has a three-dimensional curved surface shape. The radius of curvature in the left-right direction of the three-dimensional curved surface of the upper portion surface is larger than the radius of curvature in the left-right direction of the surface of the portion corresponding to the lower rib.

The surfaces of the seat portion 10 and the back portion 30 are three-dimensionally curved surfaces which are continuously concave as a whole from a portion 11 corresponding to the ischial bones to a portion corresponding to the upper edge of the ilium.

The surface from the portion 11 corresponding to the ischia to the back portion 30 (the rear side) of the rear portion of the seat portion 10 is a three-dimensional curved surface which is curved in a concave shape in a right-left direction vertical section and is continuous and continuous from the portion 11 corresponding to the ischia to the back portion 30 in a vertical direction vertical section.

The surface of the lower portion of the back portion 30 located below the position corresponding to the upper iliac edge is curved in a concave shape in the lateral cross section and is a three-dimensional curved surface continuous with the rear portion of the seat portion 10 in the vertical cross section.

The seat portion 10 of the seat cushion of the present embodiment configured as described above is placed on a seat surface of a chair for use. Since the seat portion 10 has a three-dimensionally curved surface shape, when a seated person is seated on the seat cushion, the ischia bones of the hip portion of the seated person are easily and accurately accommodated in the portion 11 corresponding to the ischia bones of the seat portion 10, and therefore, the hip portion of the seated person is less pressed, and the posture of the seated person is stabilized. In addition, since the hip portion of the seated person is not easily moved forward, and particularly, the surface shape of the portion 11 corresponding to the ischia portion of the above-described embodiment is inclined toward the front side, the forward movement of the hip portion of the seated person can be more effectively prevented.

By accommodating the sitting person's ischia in the portion 11 corresponding to the ischia in this way, the upper iliac edges and the lower ribs of the sitting person can be accurately positioned at the portion corresponding to the upper iliac edges and the portion corresponding to the lower ribs. The surface of the portion corresponding to the upper iliac edge and the portion corresponding to the lower rib is curved in a concave shape in the lateral cross section, and is a three-dimensional curved surface inclined toward the back side as going upward in the vertical cross section than the surface of the portion corresponding to the lower rib located at the upward portion, so that the back of the seated person is held in a state of being wrapped by the back 30 and supported from below. In particular, the rib of the seated person is supported so as to be lifted upward by the surface shape of the portion located upward from the portion corresponding to the lower rib, so that the feeling of pressure on the chest or the like is reduced, and breathing of the seated person is facilitated. Further, it is easy for the seated person to maintain a posture with the head raised, to increase the visual field, to grasp the surrounding situation, and to communicate with other people. Furthermore, by maintaining the seated person in the above-described posture, the shoulders are relaxed and comfortable, the forearms are easily lifted, and the hands are easily used. Further, since the seated person can sit in the above-described comfortable posture, the seated person can easily perform an action such as standing up, and can smoothly work in a state of maintaining the posture when performing an office work, for example, when used in an office chair.

In addition, the above-described embodiment has the above-described advantages due to the above-described structure, but the design may be appropriately changed within the intended scope of the present invention.

That is, although the above embodiment has been described mainly with reference to a seat cushion applied to an office chair as an example, the present invention is not limited to this, and a child chair used in school or the like also belongs to a matter of which design is appropriately changed.

In the above embodiment, the seat cushion in which the cushion body 1 is covered with the cover has been described as an example, but the cover is not an essential constituent element in the present invention. If the sleeve is used, for example, an attachment member to be attached to a chair may be provided on the sleeve. Specifically, as the attachment member, a belt-like member wound around the chair, a cloth-like member or the like may be sewn to the back surface side of the back 30 because an insertion hole portion is formed in the back portion.

The seat cushion of the present invention is provided with the cover and the cushion body, and the raw material of the cushion body is not limited to the urethane foam, and various recognized materials can be used, of course.

In the above embodiment, the seat cushion was described as an example of the embodiment of the present invention, but the same structure as that of the above embodiment may be applied to a chair. That is, the object of the present invention also includes a chair, and a chair having a seat and a back portion with the specific surface shapes described in the embodiments also falls within the scope of the present invention. It can be seen that the chair according to the present invention has the above-described advantages by adopting the same configuration as that of the above-described embodiment (the portion corresponding to the ischial bones, the portion corresponding to the upper iliac edges, the portion corresponding to the lower ribs, the upper portions, the ridges, the grooves, and the like). In addition, the chair of the present invention may be made of various materials.

As described above, the seat cushion and the seat according to the present invention do not easily press the buttocks of the seated person, and easily maintain a correct posture, so that the seated person can easily breathe.

The term "chair" as used herein has a broad meaning, and means furniture having a seat surface and a backrest portion and allowing 1 person to sit thereon.

Industrial applicability

As described above, the seat cushion and the chair according to the present invention are easy to keep a correct posture, and therefore, can be applied to office chairs, learning chairs, chairs in living rooms, and the like.

Claims

1. A chair cushion is characterized in that a cushion body is provided with a cushion body,

comprises a seat part which is abutted by the buttocks of a seated person and a back part which is abutted by the back of the seated person,

the surfaces of two parts of the seat part, which correspond to the ischia, of the seated person, against which the ischia abuts, are three-dimensional curved surfaces which are curved in a concave shape on a left-right direction vertical section and inclined to the surface side with the backward side on a front-back direction vertical section,

the seat part at least comprises a convex strip part formed from the central part to the front and a pair of concave strip parts formed at the left and right sides of the convex strip part,

the surfaces of the convex strip and the pair of concave strips are continuous on the left-right direction longitudinal section,

in order to make it easy for a seated person to move the legs, the surfaces of the concave portions are inclined so that the lowest point of the vertical section in the left-right direction is located gradually outward from the rear side to the front side, and are inclined from the portion corresponding to the ischia to the front side and then inclined toward the back side to the front side,

the surface of the back part corresponding to the upper edge of the ilium, which the ilium of the seated person abuts against, is entirely bent in a concave shape in the transverse section in the left-right direction,

the surface of the back portion, which is in contact with the lower ribs of the seated person, at a position corresponding to the lower ribs is entirely curved in a concave shape in the lateral cross section,

the surface of the portion located upward from the portion corresponding to the lower rib is a three-dimensional curved surface which is curved in a concave shape as a whole in a transverse section in the left-right direction and is inclined toward the back side as going upward in a vertical section in the up-down direction,

the radius of curvature in the left-right direction of the three-dimensional curved surface of the upper portion surface is larger than the radius of curvature in the left-right direction of the surface of the portion corresponding to the lower rib,

the back portion is shaped to wrap around the back of a seated person and is supported from below,

the seat section and the back section are formed integrally, and the continuously provided portion has a notch section whose width in the left-right direction is narrowed,

the surfaces of the seat and the back are three-dimensional curved surfaces which are continuously concave as a whole from the portion corresponding to the ischial bones to the portion corresponding to the upper edge of the ilium.

2. The seat cushion according to claim 1, wherein the surface of the portion corresponding to the ischia is inclined to the front surface side with the front side in the longitudinal section in the front-rear direction.

3. The seat cushion according to claim 1, wherein a surface of the portion corresponding to the ischia to a rear portion of the back portion of the seat portion is a three-dimensional curved surface which is curved in a concave shape in a right-left direction longitudinal section and is continuous from the surface of the portion corresponding to the ischia to a surface of the back portion in a front-rear direction longitudinal section.

4. The seat cushion according to claim 1, wherein a surface of a lower portion of the back portion located below a position corresponding to an upper edge of the ilium is a three-dimensional curved surface that is curved in a concave shape in a transverse cross section in the left-right direction and is continuous with a rear portion of the seat portion in a longitudinal cross section in the front-rear direction.

5. The seat cushion according to claim 1, wherein an angle formed by the seat portion and the back portion when viewed from the side is 90 ° or more and 110 ° or less.

6. A chair is characterized in that the chair is provided with a chair body,