JP2018191807A - Seat part for chair, chair, and method for manufacturing seat part for chair - Google Patents

Abstract

To provide a seat part for a chair excellent in body pressure dispersion when a person is seated.SOLUTION: There is provided a seat part 1 for a chair, which includes a seat plate 2 formed of a non-deformable member so that a body does not sink when a person is seated. Two recesses 3 for the ischial bone for accommodating at least a protrusion of the ischial bone are formed on a seating face 21 of the seat plate.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a seat for a chair, a chair, and a method for manufacturing the seat for a chair, and in particular, a seat for a chair that does not feel tired, a chair including the seat, and the seat for the chair. Relates to a method of manufacturing the part.

  Conventionally, a chair has been required to have a function of not feeling pain or fatigue when a seated person is seated. For example, in the case of a chair formed of a hard member (non-deformable member) such as wood, the buttocks are pressed against the seat by the weight of the seated person, and a load is applied to the buttocks between the convex part such as the ischia and the tailbone and the seating surface. The seated person feels uncomfortable. Therefore, it is common practice to reduce the burden on the seated person by forming the seat with a deformable cushion, etc., and dispersing the body pressure applied to the buttocks and thighs when the seated person is seated. Yes.

  In addition, in a chair in which a seat is formed with a deformable member such as a cushion, a chair having a recess formed on the seating surface is also known to accommodate a convex portion such as a sciatic bone or a tailbone in order to further reduce fatigue of the seated person. (See Patent Document 1). In addition, it is also known that a concave portion is formed in the cushion to accommodate a convex portion such as a sciatic bone or a tailbone instead of the seating surface of the chair, and the cushion is placed on the chair (see Patent Document 2).

  In addition, the movement of the knee is not restricted, and in order to reduce the burden on the pelvic nodule and the bottom of the genital organ, the front part is composed of an inclined surface extending forward and downward from the approximate center of the seat part of the seat part. A chair is also known in which a first dent and a second dent that is a dent following the shape of the collar are arranged on the left and right sides of the first dent (see Patent Document 3).

JP 2002-328673 A Utility Model Registration No. 3130702 Japanese Patent No. 5559442

  As described in Patent Documents 1 to 3, in the field of chairs, various contrivances are made to reduce the pain and fatigue of the seated person. However, conventionally known chairs, cushions, and the like still do not fully satisfy the function of sitting in a relaxed state where the seated person does not feel pain.

  The present invention has been made to solve the above problems. Surprisingly, conventionally, at least two convex portions of the sciatic bone are accommodated on the seating surface of the seat portion formed by a non-deformable member (hard member) that is easy to feel body pain when a seated person sits down. When the recessed portion for the sciatic bone is formed, the body pressure distribution when sitting is improved compared to a deformed member such as a cushion or a chair formed with a recessed portion such as a cushion, and as a result, the seated person can sit comfortably. I found a new chair.

  That is, an object of the present invention is to provide a seat for a chair, a chair, and a method for manufacturing the seat for a chair, which are excellent in dispersion of body pressure when seated and a seated person can sit comfortably.

  The present invention relates to a chair seat, a chair, and a method for manufacturing the chair seat described below.

(1) A seat for a chair,
The seat includes a seat plate formed of a non-deformable member that does not sink into the body when seated,
On the seating surface of the seat plate, at least two concave portions for ischia are formed to accommodate the convex portion of the ischia,
Seat for the chair.
(2) The sciatic recess has a substantially oval shape.
The seat part as described in said (1).
(3) The seat portion according to (2) above, wherein the two ischial recesses are arranged such that the distance between the major axes of the substantially oval shapes decreases toward the front edge of the seat portion. .
(4) On the seating surface of the seat plate, one concave portion for the coccyx that accommodates the convex portion of the coccyx is further formed.
The seat according to any one of (1) to (3) above.
(5) The seat plate can be divided into at least a seat plate split portion including the two ischial recesses and another seat plate split portion.
The seat according to any one of (1) to (4) above.
(6) The seat plate splitting portion including the two sciatic recesses can be further divided into seat plate splitting portions each including the sciatic recess.
The seat part as described in said (5).
(7) further including a frame,
The seat according to (5) or (6) above.
(8) The seat according to any one of (1) to (7) above,
Legs and backrest,
Including a chair.
(9) The spine recess is formed in the back rest to accommodate the convex part of the spine.
The chair according to (8) above.
(10) A method for manufacturing a seat for a chair, the manufacturing method comprising:
A molding process for molding at least the convex part of the sciatic bone of the seated person by sitting on the molding material;
A seating surface forming step of forming, on the seating surface of the seat plate constituting the seat portion, at least two sciatic recesses for accommodating at least the sciatic protrusions, based on the shape molded in the molding step;
Including at least
The seat plate is formed of a non-deformable member that does not sink into the body when seated.
Production method.

  When the seat of the present invention or the chair provided with the seat is used, the body pressure at the time of sitting can be dispersed as compared with a chair formed of a deformable member such as a conventional cushion.

FIG. 1 is a schematic perspective view of a seat 1 according to the first embodiment. FIG. 2 is a schematic perspective view of the seat 1 in the second embodiment. FIG. 3 shows a modified example of the seat portion 1 in the second embodiment. FIG. 3 (A) is a schematic perspective view of the modified example, and FIG. 3 (B) is a cross-sectional view of FIG. It is K arrow sectional drawing. FIG. 4 is a schematic perspective view of the seat portion 1 according to the third embodiment. FIG. 5A is a schematic perspective view of the chair 100. FIG. 5B is an exploded view of the chair 100. FIG. 5C is a side view of the chair 100. FIG. 5D is a diagram illustrating an example of the backrest angle adjusting mechanism. FIG. 5E is a diagram illustrating an example of the seat angle adjustment mechanism. FIG. 5F shows a state in which the angle Y is 95 degrees and the angle Z is 0 degrees. FIG. 5G shows a state in which the angle Y is 130 degrees and the angle Z is 25 degrees. FIG. 6A is a drawing-substituting photograph, which is an enlarged photograph of the seat portion 1 produced in Example 1. FIG. FIG. 6B is a drawing-substituting photograph, which is a photograph of the chair produced in Example 2. FIG. 7 is a drawing-substituting photograph and a photograph of the chair produced in Comparative Example 1. FIG. 8 is a drawing-substituting photograph and a photograph of the chair produced in Comparative Example 2. FIG. 9A is a drawing-substituting photograph and is an enlarged photograph of the urethane cushion cut in Comparative Example 3. FIG. FIG. 9B is a drawing-substituting photograph and a photograph of the chair produced in Comparative Example 3. 10A shows the measurement result of body pressure dispersion when the chair of Example 2 is used, and FIG. 10B shows the measurement result of body pressure dispersion when the chair of Comparative Example 1 is used. FIG. 10C shows a measurement result of body pressure dispersion when the chair of Comparative Example 2 is used, and FIG. 10D shows the measurement result of body pressure dispersion when the chair of Comparative Example 3 is used.

  Hereinafter, the seat part, the chair, and the manufacturing method of the seat part for the chair in the embodiment will be described in detail with reference to the drawings. In the present specification, members having the same type of function are given the same or similar reference numerals. Further, repeated description of members with the same or similar reference numerals may be omitted.

(First embodiment)
With reference to FIG. 1, a chair seat 1 (hereinafter, simply referred to as a “seat”) in the first embodiment will be described. FIG. 1 is a schematic perspective view of a seat 1 according to the first embodiment. The seat portion 1 in the first embodiment includes at least a seat plate 2 and two sciatic recesses 3 for accommodating the sciatic protrusions. Moreover, you may comprise the one concave part 4 for the tail bone which accommodates the convex part of a tail bone as needed. The sciatic recess 3 and the coccyx recess 4 are formed on the seating surface 21 of the seat plate 2.

  The seat plate 2 is formed of a non-deformable member. Examples of the non-deformable member include wood, hard resin, stone, and concrete. The material is not particularly limited as long as it does not deform when seated, but wood is preferred from the viewpoint of weight and aesthetics. In addition, even if the thin deformation | transformation member was mounted on the seat part 1 as the Example mentioned later, the effect of the seat part 1 which concerns on embodiment was acquired. This is because the body pressure is dispersed when the seated person sits down, unlike the cushion, etc., because the body sinks less, and the sciatic convex part is housed in the sciatic concave part. This is probably because there was no deviation. Therefore, in the present specification, when “non-deformable member” is described, in addition to the above-mentioned non-deformable members such as wood, hard resin, stone, concrete, etc., the body pressure can be dispersed and deformed within a range in which no front displacement occurs. It is included in the “non-deformable member” as long as it is a member. Specifically, when a seated person (for example, 80 kg) is seated, as shown in the examples to be described later, the sinking amount of the peripheral portion of the sciatic recess 3 where the body pressure is most applied is 5 mm or less in absolute value, Preferably it should just be 3 mm or less. Examples of the material include hard rubber.

  The sciatic recess 3 is not particularly limited as long as it has a size, depth, and shape that can accommodate the sciata of the seated person when seated. Examples of the shape include a substantially circular shape, a substantially oval shape, a substantially oval shape, a substantially oval shape such as a substantially oval shape, and a substantially polygonal shape. In this specification, “substantially” means “approximately”. For example, when “substantially circular” is described, not only an exact circle but also a part of an arc deviates from a part of the circumference. It is meant to include shapes (figures that are not line-symmetric about the diameter). In addition, when the seated person's buttocks were cast in the casting process described later, there were cases where the convex part for the coccyx was not confirmed due to the skeleton and the buttocks shape of the seated person. Therefore, the formation of the coccyx depression 4 is not essential and may be formed as necessary. In the case of forming the coccyal depression 4, there is no particular limitation as long as it is a size, depth, and shape that can accommodate the seated person's coccyx as with the sciatic depression 3. In the following paragraphs, when describing the “coccord for the coccyx”, the description means that the “coordinate for the coccyx” is formed, and does not mean that the “coordinate for the coccyx” is necessarily formed. .

  As described in the manufacturing method described later, in order to allow a seated person to sit more comfortably, the arrangement and shape of each seated person's sciatus and tailbone are taken, and based on the taken shape, What is necessary is just to form the recessed part 3 and the recessed part 4 for coccyx. In addition, when a plurality of seated person's buttocks were cast by the method shown in the examples described later, the dent of the sciatic portion becomes a substantially oval shape, and the long axis of the substantially oval shape is the seat portion. It has also been found that the distance may become narrower toward the front edge. Accordingly, among the shapes of the sciatic recesses 3 illustrated above, a substantially oval shape is preferable. If necessary, the major axes of the respective oval shapes may be provided in parallel, or the front edge portion. You may provide so that it may become so narrow that it goes to 22. FIG. As described above, “substantially” means an approximate. “Oval” has at least one line symmetrical line (for example, long or short axis in the case of an ellipse, long axis in the case of an egg), but when “substantially oval” is described In addition to shapes that include a line that is line-symmetric, shapes that include a line that is approximately line-symmetric (a shape that has a curved portion that overlaps most of the curves but does not overlap when folded back) are also included. The

  The seating surface 21 of the seat plate 2 is not limited as long as the body pressure when the seated person is seated can be distributed over a wide range of the buttocks and thighs, except for the recess 3 for the sciatica and the recess 4 for the coccyx. . As the shape of the seating surface 21, the substantially curved surface, a continuous curved surface along the shape of the buttocks (and thigh), or the continuous curved surface is provided on a part of the substantially planar seating surface 21. Examples include shape. When the seating surface 21 includes a curved surface, the sciatic cavity 3 and the coccyx cavity 4 may be formed on the curved surface. In the present specification, “substantially planar” means, for example, as described in Patent Document 3, instead of actively forming an inclined surface on the seating surface, if it is wood or stone, it is linear. If the surface is cut or polished flat, or resin or concrete, it means a flat pressed shape or the like. Therefore, for example, in the case of wood, even if there is a micro unevenness due to a joint or the like, it is included in the “substantially planar shape” of the present specification.

  In addition to the curved surface exemplified above, a part of the seating portion 21 may be non-planar as long as the effect of the seat portion 1 according to the embodiment is achieved. The non-planar place is, for example, the front edge portion 22 of the seating surface 21 which is a direction to put out a foot when seated, or the side edge portion of the seating surface 21 which is a direction to put out a foot when a seated person sits sideways. 23 etc., the outer peripheral part of the seating surface 21 is mentioned. Moreover, the outer peripheral part 31 of the recessed part 3 for sciatic bone, the outer peripheral part 41 of the recessed part 4 for coccyx, etc. are mentioned. By making the outer peripheral part of the seating surface 21 and the outer peripheral parts 31, 41 non-planar, it is possible to prevent the seating surface 21 from hitting the seated person's body at an acute angle, and to reduce the pain of the seated person. . In other words, it can be said that the non-planar place is a portion of the seating surface that contacts the body at an acute angle.

(Second Embodiment)
With reference to FIG. 2, the seat part 1 in 2nd Embodiment is demonstrated. FIG. 2 is a schematic perspective view of the seat 1 in the second embodiment. The seat portion 1 according to the second embodiment is configured to be divided into at least a seat plate dividing portion 11 including two ischial recesses 3 and other seat plate dividing portions 13. In the embodiment shown in FIG. 2, a portion including one coccyal depression 4 is also divided as a seat plate dividing portion 12. The shape and interval of the two ischial recesses 3 and the shape of the coccyal recess 4 formed as necessary vary depending on the adult and child, male and female. Therefore, the seat 1 in the second embodiment can be divided by the seat plate 2. For example, a plurality of seat plate dividing portions 11 having different shapes and intervals of the two ischial recesses 3 are prepared in advance, and similarly, a plurality of seat plate dividing portions 12 including the coccyal recesses 4 are prepared in advance. Thus, it is possible to easily produce the seat portion 1 in which the sciatic recess 3 and the coccytal recess 4 are arranged at an optimum position for the seated person.

  The seat portion 1 shown in FIG. 2 is divided into three seat plate divided portions (11, 12, 13), and a hole 14 is formed in each divided seat plate divided portion. By making a hole in the seat support portion of the chair, which will be described later, the seat plate dividing portion (11, 12, 13) that is optimal for the seated person is fastened with bolts, etc., so that the chair provided with the seat portion 1 can be simplified. Can be produced. In addition, the other seat plate dividing portions 13 are prepared by preparing a plurality of types of seat plate dividing portions having different widths in the direction in which the feet come out when seated (X direction in the figure). Even if the seats are different, the seat portion 1 having a comfortable seating width (X direction) can be provided. In the embodiment shown in FIG. 2, the seat plate 2 is divided into three, but it may be divided into four or more.

  FIG. 3 shows a modification of the seat 1 in the second embodiment. In the embodiment shown in FIG. 2, holes are provided in each seat plate dividing portion (11, 12, 13). However, in the modified example shown in FIG. 3, a frame body 15 is provided and each seat plate dividing portion (11, 11, 11) is provided. 12, 13) are fitted in the frame 15. 3A is a schematic perspective view in which each seat plate dividing portion (11, 12, 13) is fitted in the frame 15, and FIG. 3B is a cross-sectional view taken along the line KK in FIG. 3A. It is. In the modification of the second embodiment, the seat portion 1 can be formed by fitting each seat plate dividing portion (11, 12, 13) into the frame body 15. In a modified example, by providing a hole (not shown) in the frame body 15, the frame body 15 may be attached to a leg portion of the chair, or the frame body 15 may be placed on an existing chair or fixed by other means. . The frame body 15 may be formed of a non-deformable member similar to the seat plate 2.

(Third embodiment)
With reference to FIG. 4, the seat part 1 in 3rd Embodiment is demonstrated. FIG. 4 is a schematic perspective view of the seat portion 1 according to the third embodiment. The seat portion 1 in the third embodiment is replaced with the seat plate splitting portion 11 including the two sciatic recesses 3 in the second embodiment, and the seat plate splitting portions 111 and 112 each including the sciatic recess 3. It is divided. Further, if necessary, a spacer portion 113 may be provided between the seat plate dividing portions 111 and 112 so that the interval between the two sciatic recesses 3 can be finely adjusted. In the embodiment shown in FIG. 4, the spacer portion 113 is formed between the seat plate dividing portions 111 and 112 including the sciatic recess 3, but for example, a seat including the coccytal recess 4 as necessary. You may form in other parts, such as between the board division part 111 and 112 containing the board division part 12 and the recessed part 3 for sciatic bones, and between the frame 15 and the seat board division part 111 or 112. FIG. The spacer portion 113 can also be used in the second embodiment. Compared to the seat 1 in the second embodiment, the seat 1 in the third embodiment can more easily adjust the arrangement of the sciatic recess 3 and the coccyx recess 4.

(Fourth embodiment)
In the first to third embodiments, the seat portion 1 is formed by the seat plate 2 or the divided seat plate 2 and the frame body 15. Members may be placed. Other members include thin deformable members such as cloth, non-woven fabric, soft resin, or rubber sheet. The seat portion 1 shown in the embodiment forms a sciatic recess 3 and, if necessary, a coccytal recess 4 on the seating surface 21 of the seat plate 2 formed of a non-deformable member, thereby distributing body pressure when seated. I am trying. However, when clothes such as trousers and skirts worn by the seated person are thin, the outer peripheral part 31 of the recessed part 3 for the sciatic bone and the outer peripheral part 41 of the recessed part 4 for the tailbone may give the seated person an uncomfortable feeling. There is. In the second and third embodiments, the joint between the divided seat plate split portions and the joint between the frame body 15 and each seat plate split portion may give an uncomfortable feeling to the seated person. Therefore, if it is in the range which does not impair the effect of the seat part 1 shown in embodiment, the above-mentioned thin deformation | transformation member will be provided on the seat board 2, and the seat part 1 will be formed, and a seated person's discomfort will be reduced. it can. The thin deformable member may be in a range that does not impair body pressure dispersion, and is preferably 5 mm or less, and more preferably 3 mm or less. When a non-deformable member such as hard rubber that sinks slightly is used as the seat plate 2, the total sink amount of the non-deformable member and the thin deformable member is 5 mm or less, preferably 3 mm or less in absolute value. Good.

  In addition, what is necessary is just to form on the seating surface 21 when providing a thin deformation member. Since the deformable member is deformed when the seated person is seated, the deformed member is also deformed when the seated person sits in the recessed part 3 for the sciatic bone and the tailbone is accommodated in the recessed part 4 for the coccyx. The effect of the invention is achieved. Of course, the deformable member may be provided along the sciatic recess 3 and the coccyx recess 4.

(Embodiment of the chair)
An embodiment of the chair will be described with reference to FIG. FIG. 5A is a schematic perspective view of the chair 100. FIG. 5B is an exploded view of the chair 100. FIG. 5C is a side view of the chair 100. The chair 100 includes at least a seat portion 1, a leg portion 5, and a backrest portion 6. In the example shown in FIG. 5B, an example including a seat support part 51 that supports the seat part 1 and a back support part 7 that supports the back support part 6 is described.

  The leg 5 is not particularly limited as long as the seat 1 can be placed thereon. What is necessary is just to form like the leg part of a well-known chair, and to fix the seat part 1 to the leg part 5. In addition, when the seat part 1 is formed in each seat board division | segmentation part in which the hole 14 shown in 2nd Embodiment was formed, the seat support part 51 which formed the several hole is provided, and it uses a volt | bolt etc. You may enable it to fix each seat board division | segmentation part to the seat support part 51 in arbitrary positions. In this embodiment, the distance between the sciatic recess 3 and the backrest 6 can be easily adjusted. Of course, also in the first embodiment or the embodiment using the frame 15, the distance between the sciatic recess 3 and the backrest 6 may be adjusted by adjusting the position where the seat 1 is fixed.

  When the seated person sits on the seat part 1, the backrest part 6 is configured so that a load is easily applied in the direction in which the seated person's sciatus and tailbone are accommodated in the sciatic cavity 3 and the coccytal cavity 4, respectively. It is desirable to form. When a seated person sits with his or her own sciatic bone and coccyx consciously accommodated in the sciatic recess 3 and coccyal recess 4, the backrest 6 is formed of a thick soft material such as a cushion. May be. However, generally, when the backrest portion is formed of a soft material such as a thick cushion, the seated person is leaned against the cushion and the like, and as a result, the seated person's buttocks may be displaced forward. Therefore, it is preferable to form the backrest portion 6 with a non-deformable member similar to the seat plate 2. As described above, if the occupant is leaning against the backrest 6 and the buttocks do not deviate forward, for example, the backrest in which a thin deformable member is formed of a non-deformable member as in the seat 1. You may form on the part 6. FIG. Moreover, you may form the recessed part 61 for spine which accommodates the convex part of a spine in the backrest part 6. FIG. When a thin deformable member is also formed on the backrest 6, the thin deformable member may be formed along the spine recess 61 or may not be formed.

  The backrest portion 6 in the chair is required to have an appropriate angle depending on the use purpose of the seated person. For example, when used for work, it is more suitable to be close to the vertical, and when rest is intended, it is more comfortable to lie back. The same applies to the seat portion 1, for example, it is suitable for work to be near horizontal, and for rest, it is more comfortable to incline backward. Therefore, as shown in FIG. 5C, the chair 100 has a backrest portion angle adjustment mechanism that adjusts the angle Y between the seat portion 1 and the backrest portion 6 as necessary, and the seat portion with respect to the leg portion 5. A seat angle adjusting mechanism that adjusts the angle Z with respect to the horizontal plane 1 may be included. The back rest angle adjusting mechanism is not particularly limited as long as the angle Y of the back rest 6 can be adjusted with respect to the seat 1, and a known mechanism may be used. For example, as shown in FIG. 5D, an angle adjustment plate 71 having a plurality of angle adjustment holes 72 formed in the back support portion 7 is fixed, and a plurality of angle adjustment holes 73 are also formed in the seat support portion 51. A mechanism for adjusting the angle Y of the backrest portion 6 by fixing it with a bolt or the like at a desired angle position can be mentioned. That is, in the example shown in FIG. 5D, the seat support part 51 and the back support part 7 constitute a back support angle adjusting mechanism. In addition, the angle Y may be adjusted by a ratchet mechanism.

  The seat angle adjusting mechanism is not particularly limited as long as the angle Z of the horizontal plane of the seat 1 can be adjusted with respect to the leg 5, and a known mechanism may be used like the backrest angle adjusting mechanism. FIG. 5E is a view showing an example of the seat angle adjusting mechanism, and the front edge side end 511 of the seat support 51 is attached to the leg 5 so as to be rotatable. Then, a plurality of angle adjustment holes 53 are formed in the leg portion 5, and the angle adjustment holes 52 of the seat support portion 51 and the angle adjustment holes 53 of the leg portion 5 are connected using bolts or the like at the desired angle. There is a mechanism for adjusting the angle Z of the seat 1 by fixing. That is, in the example shown in FIG. 5E, the leg 5 and the seat support 51 constitute a seat angle adjustment mechanism. In addition, the angle Z may be adjusted by a ratchet mechanism.

  In addition, 90 degrees-180 degrees are preferable and, as for the angle Y with respect to the seat part 1 of the backrest part 6, 95 degrees-155 degrees are more preferable. The angle Z of the seat portion 1 with respect to the horizontal plane is preferably 0 degrees to 30 degrees, and more preferably 0 degrees to 25 degrees. FIG. 5F illustrates a state in which the angle Y is 95 degrees and the angle Z is 0 degrees, and FIG. 5G illustrates a state in which the angle Y is 130 degrees and the angle Z is 25 degrees.

(Embodiment of the manufacturing method of a seat part)
Since the positions of the sciatic bone and the tailbone are different depending on the seated person, the seated person can sit comfortably when the custom-made seat portion 1 is manufactured. Seat 1 is
-A molding process in which at least the convex part of the sciatic bone of the seated person is cast by sitting on the molding material,
A seating surface forming step of forming, on the seating surface 21 of the seat plate 2 constituting the seat portion 1, at least two sciatic recesses 3 for accommodating the sciatic protrusions, based on the shape taken in the casting step;
At least, the seat 1 can be manufactured. In addition, when the convex part of the coccyx is also formed in the molding process, one coccyal concave part 4 that accommodates the convex part of the coccyx may be formed in the seating surface forming process.

  The material for molding is not particularly limited as long as it is a material that can be molded because the ischia and coccyx portions are depressed by the load of the buttocks when seated. Note that, in the molding process of the present embodiment, the ischia and coccyx parts, which are the most loaded parts of the buttocks when seated, are different from taking the shape faithfully as it is, for example, taking a foot with gypsum. However, it is preferable that the material is such that it does not sink further when a certain amount of sinking occurs due to a load applied to the surrounding buttocks and thighs. Examples of the material include gypsum, resin, and the like that balance the load by placing them in clay, rubber bags, or the like. In addition, after sitting on a commercially available bead cushion, the buttock may be molded by removing air from the cushion. Examples of such a cushion include sweet cheeks manufactured by Jackson Kayak. The seating surface forming step is not particularly limited as long as the sciatic recess 3 and the coccyx recess 4 can be formed based on the shape taken in the casting step. For example, when wood, plastic, or stone is used as the seat plate 2 What is necessary is just to form by cutting. In the cutting process, the peripheries of the sciatic recesses 3 and the coccyx recesses 4 may be cut into curved surfaces so as not to cause discomfort to the seated person. Moreover, you may form the seat board 2 using a 3D printer based on the shape shape | molded.

  The present invention will be described in detail with reference to the following examples, which are provided merely for the purpose of illustrating the present invention and for reference to specific embodiments thereof. These exemplifications are for explaining specific specific embodiments of the present invention, but are not intended to limit or limit the scope of the invention disclosed in the present application.

<Example 1>
[Preparation of seat part 1]
First, paper clay (500 g made by Gintori Sangyo Co., Ltd.) was uniformly spread on a wooden frame, and the surface was covered with Saran Wrap (registered trademark). Next, a monitor (male: height 170 cm, weight 52 kg) was seated on the clay to mold the buttock. Next, a seat was produced by cutting wood based on the shape taken. In addition, the recessed part for sciatic bone and the recessed part for coccyx were cut | disconnected separately, and the seat part was set as the structure divided | segmented by the division part. FIG. 6A is an enlarged photograph of the produced seat. The shape of the sciatic recess was an ellipse, and the dimensions were about 11 cm for the long axis, about 8 cm for the short axis, and the depth of the deepest part of the dent was about 25 mm. On the other hand, the shape of the concave part for the coccyx was circular, the diameter was about 5 cm, and the depth of the deepest part of the dent was about 20 mm.

[Making a chair]
<Example 2>
A leg part and a seat support part were produced by combining wood. Next, the hole formed in each seat plate division | segmentation part of the seat part produced in Example 1 and the hole formed in the seat support part were fixed with the volt | bolt. In addition, the back support part and back support part formed with a concave part for the spine using wood are manufactured, and the seat support part and the back support part are fixed with bolts so that the angle Y to the seat part is about 100 degrees. did. FIG. 6B is a photograph of the chair produced in Example 2.

<Comparative Example 1>
A chair was prepared in the same manner as in Example 2 except that the sciatic recess and the coccyx recess were not formed in the seat. FIG. 7 is a photograph of the chair produced in Comparative Example 1.

<Comparative Example 2>
Comparative Example 2 in which a urethane cushion (product name: nude urethane seating, distributor: DCM Holdings Co., Ltd., size: width 40 cm × depth 40 cm × thickness 5 cm) is placed on the chair prepared in Comparative Example 1 It was a chair. FIG. 8 is a photograph of the chair produced in Comparative Example 2.

<Comparative Example 3>
A chair was produced in the same manner as in Comparative Example 2 except that the urethane cushion used in Comparative Example 2 was cut with a concave part having the same size as the concave part for ischia and the concave part for the coccyx. FIG. 9A is an enlarged photograph of a cut urethane cushion, and FIG. 9B is a photograph of the chair produced in Comparative Example 3.

[Body pressure dispersion test when seated]
Next, a body pressure dispersion test when sitting on the chair produced in Example 1 and Comparative Examples 1 to 3 was performed. The measurement device was a body pressure dispersion measuring device SR soft vision numerical version (manufactured by Sumitomo Riko Co., Ltd.) and measured according to the “instruction manual”. In Comparative Examples 2 and 3, since a urethane cushion was placed, the height of the leg was adjusted when measuring using the chairs of Example 2 and Comparative Example 1.

  10A is the chair of Example 2, FIG. 10B is the chair of Comparative Example 1, FIG. 10C is the chair of Comparative Example 2, and FIG. 10D is the chair of Comparative Example 3. The measurement result of body pressure dispersion at the time is shown. First, as is clear from FIG. 10 (B), in the chair of Comparative Example 1, a very strong pressure was applied to the portion where the ischia abuts, and almost no body pressure dispersion was observed. On the other hand, in the chair of Comparative Example 2 on which a urethane cushion was placed, body pressure dispersion was measured over a wider range as compared with FIG. 10 (B), as is clear from FIG. 10 (C). Further, in the chair of Comparative Example 3 in which the sciatic cavity and the coccyx cavity are formed on the urethane cushion, as is clear from FIG. 10D, the pressure center point (numerical value is Many areas with a numerical value of 66 or more around the (highest place) were seen. This indicates that the pressure is distributed around the pressure center point. In Comparative Example 3, although a sciatic recess was provided, high pressure was observed in the sciatic portion because a sheet called Smart Rubber (registered trademark) was placed on the seating surface of the chair for measurement. This is because it is mounted on and measured. Although Smart Rubber (registered trademark) is made of a soft material, it does not fully expand and contract along the sciatic recess when the monitor is seated, and Smart Rubber (registered trademark) does not fit in the sciatic recess. This is thought to be due to the action of pushing up the sciatica of the monitor. The same applies to Example 2 described later.

  And in the chair of Example 2 which formed the recessed part for ischia and the recessed part for the coccyx in the wood, as is clear from FIG. 10 (A), compared with FIGS. 10 (B) to (D), There were a lot of surrounding areas of 66 or more. This indicates that, when compared with the chairs of Comparative Examples 1 to 3, when the monitor is seated, the pressure is not concentrated around the sciatic bone but is distributed over a wide range of the buttocks. From the above results, the chair of Example 2 in which the sciatic cavity and the coccyx cavity were formed in the wood in which the body pressure is difficult to disperse is a cushion that was thought to easily disperse the body pressure. It has been scientifically confirmed that there is a surprising effect that the body pressure can be dispersed more than the chair with the concave part for the coccyx. Furthermore, in Example 2, since the effect of body pressure dispersion was confirmed even when Smart Rubber (registered trademark) was placed on the sciatic cavity and the coccyx cavity, the effect of the present invention was applied to the seat. It was also confirmed that a thin deformable member can be placed within a range that does not impair.

[Evaluation of seated person]
Next, when the sitting comfort when seated on the chairs of Example 2 and Comparative Examples 1 to 3 was confirmed on the monitor, in the case of the chair of Example 2, there was no pain in the buttocks and somewhere in the body. It was confirmed that he can sit in a weak state without feeling that the power is in. In addition, it was confirmed that there was no change in the seating feeling (fatigue, pain, etc.) even after sitting for 15 minutes.

  Traditionally, wood chairs were thought to cause pain to the occupant. In the present invention, a seated person can be comfortably seated in a chair by forming a recessed part for ischia and a recessed part for the coccyx in a non-deformable member such as wood. Furthermore, since a non-deformable member is used, a chair whose seating comfort does not change with time can be provided unlike a cushion or the like. Therefore, it is useful for the chair industry.

DESCRIPTION OF SYMBOLS 1 ... Seat part, 2 ... Seat plate, 3 ... Recessed part for sciatic bone, 4 ... Recessed part for coccyx, 5 ... Leg part, 6 ... Back support part, 7 ... Back support part, 11 ... Including two recessed parts 3 for sciatic bone Seat plate division part, 12 ... Seat plate division part including one coccyal depression 4, 13 ... Other seat plate division parts, 14 ... Hole, 15 ... Frame body, 21 ... Seating surface, 22 ... Front edge part, 23 DESCRIPTION OF SYMBOLS Side edge part, 31 ... Outer peripheral part of sciatic cavity, 41 ... Outer peripheral part of coccytal cavity, 51 ... Seat supporting part, 52 ... Angle adjusting hole, 53 ... Angle adjusting hole, 61 ... Spine concave part, 71 DESCRIPTION OF SYMBOLS ... Angle adjustment plate, 72 ... Angle adjustment hole, 73 ... Angle adjustment hole, 100 ... Chair, 111 ... Seat plate division | segmentation part containing the recessed part 3 for sciatic bone, 112 ... Seat plate division | segmentation part containing the recessed part 3 for sciatic bone, 113 ... Spacer Part, 511 ... front edge side end part

Claims (10)

A seat for a chair,
The seat includes a seat plate formed of a non-deformable member that does not sink into the body when seated,
On the seating surface of the seat plate, at least two concave portions for ischia are formed to accommodate the convex portion of the ischia,
Seat for the chair. The sciatic recess has a substantially oval shape;
The seat according to claim 1.   The seat portion according to claim 2, wherein the two ischial recesses are arranged such that a distance between major axes of the substantially oval shapes becomes narrower toward a front edge portion of the seat portion. On the seating surface of the seat plate, one coccyx concave portion for accommodating the coccyx convex portion is further formed,
The seat part as described in any one of Claims 1 thru | or 3. The seat plate can be divided into at least a seat plate split portion including the two ischial recesses and another seat plate split portion.
The seat part as described in any one of Claims 1 thru | or 4. The seat plate splitting portion including the two sciatic recesses can be further divided into seat plate splitting portions each including the sciatic recess.
The seat according to claim 5. Further including a frame,
The seat according to claim 5 or 6. The seat according to any one of claims 1 to 7,
Legs and backrest,
Including a chair. The spine recess is formed in the back rest to accommodate the convex part of the spine.
The chair according to claim 8. A method for manufacturing a seat for a chair, the manufacturing method comprising:
A molding process for molding at least the convex part of the sciatic bone of the seated person by sitting on the molding material;
A seating surface forming step of forming, on the seating surface of the seat plate constituting the seat portion, at least two sciatic recesses for accommodating at least the sciatic protrusions, based on the shape molded in the molding step;
Including at least
The seat plate is formed of a non-deformable member that does not sink into the body when seated.
Production method.