Posture detection system and posture detection method

Abstract

A posture detection system according to one embodiment of the present invention is a posture detection system that detects the posture of a user sitting on a seat cushion. The seat cushion is provided with a seat section having a hip support section and a lumbar support section having a sacrum support section. The posture detection system is provided with: a seat part sensor which is attached to the seat part and detects whether or not the user is seated on the seat part; and a sacrum support part sensor which is attached to the sacrum support part and detects the posture of the user seated on the seat part. A posture determination unit that determines the posture of the user on the basis of a result measured by the sacrum support unit sensor; and an alarm unit that outputs an alarm when the posture determination unit determines that the posture of the user is poor.

Description

Technical Field

[0001] The present invention relates to a posture detection system and a posture detection method for detecting the posture of a user sitting on a seat cushion. Background Art

[0002] Japanese Patent Application Laid-Open No. 6-86725 describes a seat device that includes a seat cushion that supports the buttocks of a seated person through a seat surface, a seat back that supports the back of the seated person through a support surface, an actuator that drives the support surface of the seat back to change its shape, and a detection device that extracts elements related to the body shape features of the upper body of the seated person.

[0003] The actuator is an airbag installed inside the seat back. The detection device is a seat pressure sensor installed inside the seat cushion and inside the seat back. The detection device extracts the body shape features of the upper body of the seated person from the detection values ​​of each seat pressure sensor. The actuator inflates the airbag according to the extracted body shape features to control the posture of the seated person.

[0004] Japanese Patent Application Laid-Open Nos. 2019-151251 and 2021-112665 ​​describe seats that include a first cushion sensor disposed at a position corresponding to the buttocks of a seated person, and a second cushion sensor located closer to the front side of the seated person than the first cushion sensor.

[0005] The seat further includes a first backrest sensor disposed at a lower portion of a seat backrest, a second backrest sensor disposed above the first backrest sensor, and a control unit. The control unit determines the motion of the seated person based on outputs of at least two of the first cushion sensor, the second cushion sensor, the first backrest sensor, and the second backrest sensor. Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 6-86725 Patent Document 2: Japanese Patent Application Publication No. 2019-151251 Patent document 3: Japanese Patent Application Publication No. 2021-112665. Summary of the invention

[0007] The posture detection system involved in the present invention is (1) a posture detection system for detecting the posture of a user sitting on a seat cushion, wherein the seat cushion has a seat portion and a lumbar support portion, the seat portion has a buttocks support portion for supporting the user's buttocks, and the lumbar support portion has a sacrum support portion for supporting the user's sacrum from the rear, the posture detection system comprising: a seat portion sensor, the seat portion sensor is installed on the seat portion, and detects whether the user is sitting on the seat portion; a sacrum support portion sensor, the sacrum support portion sensor is installed on the sacrum support portion, and detects the posture of the user sitting on the seat portion; a posture determination portion, the posture determination portion determines the user's posture based on the result measured by the sacrum support portion sensor; and an alarm portion, the alarm portion outputs an alarm when the posture determination portion determines that the user's posture is poor.

[0008] In the above-mentioned posture detection system, the seat cushion has a seat portion having a buttocks support portion for supporting the user's buttocks, and a sacrum support portion for supporting the user's sacrum from the rear. The posture detection system has a seat portion sensor for detecting whether the user is sitting on the seat portion of the seat cushion. By detecting whether the user is sitting on the seat portion by the seat portion sensor, the time the user sits on the seat portion can be calculated. The user can understand whether he sits for a long time, so that the problem of poor blood circulation in the waist and legs or decreased muscle strength can be avoided. The posture detection system has a sacrum support portion sensor that is arranged on the sacrum support portion and detects the posture of the user sitting on the seat cushion. The sacrum is a part protruding from the back of the user. By arranging the sacrum support portion sensor on the sacrum support portion supporting the sacrum, the user's posture can be detected with high accuracy. The posture detection system has an alarm portion that outputs an alarm when the posture determination portion determines that the posture is poor. By making the alarm portion output an alarm when the posture is poor, the user can understand the situation of his poor posture, thereby reducing the possibility of damaging the body due to poor posture.

[0009] (2) In the above (1), the sacrum support sensor may also detect whether the user's sacrum is in contact with the sacrum support sensor. The posture determination unit may determine that the user's posture is hunched when the user's sacrum is not in contact with the sacrum support sensor. In this case, when the user leans forward and the sacrum is not in contact with the sacrum support sensor, the posture determination unit determines that the posture is hunched. Since the hunched posture is determined by the presence or absence of contact with the sacrum support sensor, the user's posture can be grasped with high precision to control the hunchback.

[0010] (3) In the above (1) or (2), the sacrum support sensor may measure the load of the user's sacrum on the sacrum support sensor. The posture determination unit may determine that the user's posture is excessively leaning backward when the load measured by the sacrum support sensor is greater than a certain value. In this case, when the load on the sacrum support sensor is greater than a certain value, the posture determination unit determines that the posture is excessively leaning backward. Since whether or not the user is leaning backward excessively is determined by the load on the sacrum support sensor, it is possible to suppress the situation where the user is leaning backward excessively and the abdominal muscle strength is reduced.

[0011] (4) In any of the above (1) to (3), the seat portion may have a pair of thigh support portions arranged in the left-right direction from the perspective of the user sitting on the seat portion. The posture detection system may further have a pair of thigh support sensors, which are installed on each thigh support portion of the pair of thigh support portions and measure the load on the thigh of the user sitting on the seat portion. In this case, by measuring the load on the left and right thighs of the user by the pair of thigh support sensors respectively, the left and right balance of the thighs can be grasped. Furthermore, when one of the pair of thigh support sensors detects the load and the other does not detect the load, it can be grasped that the user may have crossed his legs. Therefore, the posture of the user sitting on the seat cushion can be grasped with higher accuracy.

[0012] (5) In any of the above (1) to (4), the posture detection system may include a fabric on which a seat sensor and a sacrum support sensor are mounted and which covers at least a portion of a core material of a seat cushion. In this case, the seat sensor and the sacrum support sensor are mounted on the fabric, and the fabric covers at least a portion of the core material. Since the seat sensor and the sacrum support sensor can be mounted on the seat cushion by covering the core material of an existing seat cushion with the fabric, the seat sensor and the sacrum support sensor of an existing seat cushion can be easily configured.

[0013] (6) In the above (5), the posture detection system may include an outer fabric covering the core material, and the fabric may be an inner fabric covered by the outer fabric. In this case, the outer fabric is provided outside the inner fabric on which the seat sensor and the sacrum support sensor are mounted. Since the outer fabric can be removed and washed, a more hygienic seat cushion can be obtained, and the seat cushion can be used for a longer period of time.

[0014] (7) In the above (4), the core material of the seat cushion may have a recess formed on the upper surface of the seat portion and a recess formed on the upper surface of the thigh support portion. The seat sensor may be embedded in the recess of the seat portion, and the thigh support sensor may be embedded in the recess of the thigh support portion.

[0015] (8) In any one of the above (1) to (5), the sacrum support portion may have a protruding surface in a curved shape protruding forward and a recessed portion recessed rearward from the protruding surface, and the sacrum support portion sensor may be mounted in the recessed portion of the sacrum support portion.

[0016] (9) In the above (4), the posture detection system may include a fabric covering at least a portion of the core material of the seat cushion. The fabric may be an inner fabric on which the seat sensor, the sacrum support sensor, and the thigh support sensor are mounted.

[0017] (10) In the above (5), the fabric covers only a portion of the core material. The fabric may be fixed to the core material so as to cover the seat portion and the sacrum support portion.

[0018] (11) In the above (4), the seat portion may extend in a first direction and a second direction, the first direction being a front-rear direction when viewed from a user sitting on the seat portion, and the second direction being a left-right direction when viewed from a user sitting on the seat portion. The posture detection system may include: two seat portion sensors arranged along the second direction; one sacrum support portion sensor; and two thigh support portion sensors arranged along the second direction.

[0019] (12) In any one of the above (1) to (11), the buttocks support portion includes a pair of ischium support portions that support ischiums of a user sitting on the seat portion, and the seat portion sensor is disposed around each of the pair of ischium support portions.

[0020] (13) In any one of the above (1) to (12), the posture detection system may include a leg crossing determination unit that determines whether the legs of the user sitting on the seat are crossed.

[0021] (14) In the above (3), the posture determination unit may determine that the user's posture is appropriate when the load measured by the sacrum support sensor has not reached a certain value.

[0022] (15) In the above (4), the posture determination unit may calculate a difference between loads on the thigh support sensors measured by the pair of thigh support sensors.

[0023] (16) In the above (4), the posture determination unit can calculate the absolute value of the difference between the load on one thigh support sensor received from the left thigh and the load on the other thigh support sensor received from the right thigh. When the calculated absolute value is greater than a certain value, it is determined that the left and right balance is poor and the posture is inappropriate. When the calculated absolute value is not greater than the certain value, it is determined that the left and right balance is good.

[0024] (17) In the above (4), the posture detection system may include a leg crossing determination unit, which determines whether the legs of a user sitting on the seat are crossed, and the leg crossing determination unit determines that the legs are crossed when one thigh support sensor of a pair of thigh support sensors receives a load from the thigh and the other thigh support sensor does not receive a load from the thigh.

[0025] (18) In any of the above (1) to (17), the posture detection system may have a sitting determination unit for determining whether the user is sitting on the seat portion, and a display unit for displaying the results of determination by the sitting determination unit and the posture determination unit, respectively, and the display unit will display at least any one of the sitting time on the seat portion, the time of proper posture, the time of hunching over, the time of excessive backward leaning, the time of poor left and right balance, and the time of crossing legs in the form of a time graph.

[0026] (19) In any of the above (1) to (18), the posture detection system may have a sitting determination unit for determining whether the user is sitting on the seat portion, and a display unit for displaying the results of determination by the sitting determination unit and the posture determination unit, respectively, and the display unit displays the determination results of the sitting determination unit and the determination results of the posture determination unit in the form of comments.

[0027] The posture detection method involved in the present invention is (20) a posture detection method for detecting the posture of a user sitting on a seat cushion, wherein the seat cushion has a seat portion and a lumbar support portion, the seat portion has a buttocks support portion for supporting the user's buttocks, and the lumbar support portion has a sacrum support portion for supporting the user's sacrum from the rear, the posture detection method comprising: a process of detecting whether the user is sitting on the seat portion by a seat portion sensor installed on the seat portion; a process of detecting the posture of the user sitting on the seat portion by a sacrum support portion sensor installed on the sacrum support portion; a process of determining the user's posture based on the result detected by the sacrum support portion sensor; and a process of outputting an alarm when it is determined that the user's posture is poor in the determination process.

[0028] In the above-mentioned posture detection method, a process of detecting whether the user is sitting on the seat portion is included. Since the time the user sits on the seat portion can be calculated by detecting whether the user is sitting on the seat portion by the seat portion sensor, it is possible to grasp whether the user sits for a long time. In this way, the problems of poor blood circulation in the waist and legs and decreased muscle strength can be avoided. The posture detection method includes a process of detecting the posture of the user sitting on the seat portion by a sacrum support portion sensor. The sacrum is a protruding part of the back of the user. By detecting the posture by the sacrum support portion sensor provided in the sacrum support portion supporting the sacrum, the posture of the user can be detected with high accuracy. The posture detection method includes a process of outputting an alarm when the posture determination unit determines that the posture is poor. By causing the alarm unit to output an alarm when the posture is poor, the user can grasp the situation of his or her poor posture, thereby reducing the possibility of damaging the body due to poor posture. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a perspective view showing a core material of a seat cushion used in the posture detection system according to the embodiment. Figure 2 For display Figure 1 Top view of the core material. Figure 3 For display Figure 1 Bottom view of the core material. Figure 4 for Figure 2 AA line section view. Figure 5 For display Figure 1 Side view of the core material. Figure 6 The figure is a cross-sectional view schematically showing a seat sensor, a sacrum support sensor, a thigh support sensor, and a fabric of the posture detection system according to the embodiment. Figure 7 4 is a functional block diagram of a posture detection system according to an embodiment. Figure 8 For display Figure 7 FIG. 1 is a diagram of an example of a display screen shown on a display unit of a posture detection system. Fig. 9 A cross-sectional view schematically showing a seat sensor, a sacrum support sensor, a thigh support sensor, and a fabric of a posture detection system according to a modified example. Fig.10 A perspective view showing a lumbar support member and a seat cushion to which a posture detection system and a posture detection method according to an embodiment are applicable. Fig.11 For display Fig.10 A top view of the lumbar support and seat cushion. Fig.12 For viewing from the rear Fig.10 A three-dimensional view of a lumbar support and a seat cushion. Fig.13 For display Fig.10 A perspective view of a lumbar support member. Fig.14 For illustration Fig.13 A top view of the action of the lumbar support. DETAILED DESCRIPTION

[0030] For example, in an office space, people sometimes sit on a cushion placed on the seat of a chair to work for a long time. In this case, if the user of the cushion has a bad posture while sitting on the cushion, the user may hurt himself. Therefore, people need to be able to detect the posture of the user sitting on the cushion with high accuracy. If you sit for a long time, it will cause problems such as poor blood circulation in the waist and legs and decreased muscle strength. This requires people to be able to grasp whether they are sitting on the cushion for a long time.

[0031] The present embodiment aims to provide a posture detection system and a posture detection method that can accurately grasp the posture of a user sitting on a seat cushion and can grasp whether the user has been sitting for a long time.

[0032] The following will describe the embodiments of the posture detection system and posture detection method involved in the present invention with reference to the accompanying drawings. In the description of the accompanying drawings, the same symbols are given to the same or equivalent elements, and repeated descriptions are appropriately omitted. For ease of understanding, parts of the accompanying drawings are sometimes simplified or exaggerated, and the size ratios, etc. are not limited to the descriptions in the accompanying drawings.

[0033] In an embodiment, a posture detection system detects the posture of a user sitting on a seat cushion. The seat cushion is made of a flexible material. "Flexible material" refers to a cushioning material that deforms when supporting a body and receiving a load. The seat cushion includes a seat portion and a lumbar support portion, the seat portion having a buttocks support portion supporting the user's buttocks, and the lumbar support portion having a sacrum support portion supporting the user's sacrum from behind.

[0034] "User" refers to the user of the cushion, for example, a person sitting on the cushion. "Buttocks" refers to the raised portion of the lower back of the body, that is, the body portion located below the waist and above the thigh. "Sitting" means sitting on the cushion. "Seat portion" refers to the portion of the cushion that the buttocks abut when sitting on the cushion. "Thigh portion" refers to the portion of the leg from the base of the leg to the knee. The buttocks support portion has, for example, a pair of ischium supports. "Ischium" refers to the portion located at the lowest part of the pelvis when the user sits on the seat portion.

[0035] "Posture" indicates the physical state of a user sitting on the seat cushion. The posture detection system according to the embodiment outputs an alarm when the user has a bad posture. "Bad posture" indicates at least one of, for example, a state in which the back of the user sitting on the seat portion is hunched, a state in which the back of the user sitting on the seat portion is leaned back too much, and a state in which the legs are crossed.

[0036] Figure 1 The seat cushion 100 (see Figure 6 ) is a three-dimensional image of the core material 1. Figure 1 As shown, the core material 1 includes a seat portion 2 extending in the horizontal direction and a lumbar support portion 3 extending upward from the seat portion 2. The core material 1 is made of, for example, urethane foam.

[0037] As an example, the core material 1 is formed by polyurethane mold molding. When the core material 1 is composed of polyurethane foam and formed by polyurethane mold molding, the core material 1 composed of a flexible material can be easily manufactured. The core material 1 is, for example, received in the fabric 20 of the seat cushion 100 (see Figure 6 ) is used.

[0038] It should be noted that the above-mentioned flexible material includes, for example, a thermoplastic elastomer. The flexible material may be a material having elasticity that deforms according to the load when the body is supported. The flexible material may be a resin (for example, polypropylene, polyester, or polyethylene) that deforms when the body is supported and subjected to the load. The type of the flexible material may be appropriately changed.

[0039] The seat portion 2 extends in a first direction D1 and a second direction D2 intersecting the first direction D1. The first direction D1 is a front-rear direction when viewed from a user sitting on the seat portion 2, and the second direction D2 is a left-right direction when viewed from a user sitting on the seat portion 2. The seat portion 2 has a thickness in a third direction D3 intersecting the first direction D1 and the second direction D2. For example, the third direction D3 is a vertical direction.

[0040] Hereinafter, the forward direction when viewed from the user sitting on the seat portion 2 is sometimes referred to as "front", "front side" or "front", and the direction opposite to the forward direction is sometimes referred to as "rear", "rear side" or "rear". However, these directions are for convenience of description and do not limit the positions or directions of the various parts.

[0041] Figure 2 is a top view of the core material 1. Figure 1 as well as Figure 2As shown, the seat portion 2 includes a buttocks support portion 4 for supporting the buttocks of the user, and a thigh support portion 5 for supporting the thighs of the user. The buttocks support portion 4 and the thigh support portion 5 are arranged side by side along the first direction D1. The buttocks support portion 4 includes a pair of ischium support portions 6 for supporting the ischium of the user sitting on the seat portion 2.

[0042] For example, the seat portion 2 has a vent hole 2b. The vent hole 2b extends downward from the upper surface 4b of the buttocks support portion 4 or the upper surface of the thigh support portion 5. The upper end of the inner wall defining the vent hole 2b may be rounded to form a rounded corner. In a plan view, a plurality of vent holes 2b are arranged side by side from the rear to the front.

[0043] For example, in a plan view (a plan view in a direction in which the lumbar support portion 3 is located above the seat portion 2), a plurality of (for example, six) ventilation holes 2b may be arranged on both sides (left and right sides) in the second direction D2. For example, three ventilation holes 2b may be arranged on both sides in the second direction D2.

[0044] For example, two ventilation holes 2b are arranged along the second direction D2. The distance between the two ventilation holes 2b arranged along the second direction D2 increases, for example, from the buttocks support part 4 toward the thigh support part 5 (as it moves toward the front). As an example, the plurality of ventilation holes 2b are arranged in an "eight" shape when viewed from above.

[0045] For example, in the core material 1, the ischial support portion 6 (e.g., the through hole 6c described later) is formed by polyurethane mold molding, and the vent hole 2b is formed by die cutting. In this case, the mold used in manufacturing the core material 1 does not need to form the portion of the vent hole 2b, so the shape of the mold can be simplified. Furthermore, when liquid polyurethane is molded in the mold, the escape path of the air in the liquid polyurethane can be ensured, so the finished product of the core material 1 can be made smooth.

[0046] The ischium support portion 6 is formed on the upper surface 4b of the buttocks support portion 4 and is recessed relative to the upper surface 4b. The buttocks support portion 4 has a pair of ischium support portions 6 arranged along the second direction D2. The ischium support portion 6 has a recessed portion 6b recessed from the upper surface 4b of the buttocks support portion 4. The shape of the ischium support portion 6 when viewed from above is set to have a major axis and a minor axis. For example, the shape of the ischium support portion 6 when viewed from above is an oblong (as an example, an ellipse). However, the shape of the ischium support portion 6 when viewed from above is not limited to an oblong or an ellipse, and may also be a rectangle, a rounded rectangle, a rhombus, or a rounded rhombus, and may be appropriately changed.

[0047] The extension line L1 of the long axis of one of the ischium support parts 6 and the extension line L2 of the long axis of the other ischium support part 6 intersect each other. For example, the intersection angle θ1 between the extension line L1 and the extension line L2 is, for example, 40° or more and 150° or less. The intersection angle θ1 may be 50° or more, 60° or more, 75° or more, or 90° or more. The intersection angle θ1 may be 135° or less, 120° or less, or 110° or less. As an example, the intersection angle θ1 is 100°.

[0048] The intersection P of the extension lines L1 and L2 is located closer to the thigh support 5 (closer to the front) than the pair of ischium support parts 6. The intersection P is located on the thigh support 5 side relative to the center of each ischium support part 6 in a plan view. The intersection P is located on the opposite side of the lumbar support part 3 from the pair of ischium support parts 6. Therefore, the pair of ischium support parts 6 form an inverted "eight" shape in a plan view (a plan view in which the lumbar support part 3 is located on the upper side of the seat part 2).

[0049] The distance between the centers of the pair of ischium support parts 6 (the distance between the centers of the pair of ischium support parts 6) is, for example, 7 cm or more and 15 cm or less. As an example, the distance is 10 cm. The distance from the lumbar support part 3 to the center of the ischium support part 6 is, for example, 5 cm or more and 15 cm or less. As an example, the distance from the lumbar support part 3 to the center of the ischium support part 6 is 10 cm. When each length and each distance are within the range of the above values, the user's ischium can be more well matched to each ischium support part 6 in the pair of ischium support parts 6.

[0050] For example, each ischium support portion 6 has a through hole 6c penetrating downward from the upper surface 4b of the buttocks support portion 4. Each ischium support portion 6 has an inner wall defining the through hole 6c and a tapered surface 6f located between the inner wall and the upper surface 4b. Figure 3 1 is a bottom view showing the core material 1. Figure 2 as well as Figure 3 As shown, the area of ​​the ischial support portion 6 when viewed from above is larger than the area of ​​the ischial support portion 6 when viewed from below.

[0051] The core material 1 has a mounting surface S (see Figure 4 ) is in contact with the lower surface 1b. For example, the inner wall defining the through hole 6c connects the lower surface 1b and the tapered surface 6f to each other. At least one of the end of the inner wall of the through hole 6c on the lower surface 1b side and the end of the inner wall on the tapered surface 6f side may be R-chamfered to form a rounded corner.

[0052] The conical surface 6f forms a recessed portion 6b that is recessed relative to the upper surface 4b. The conical surface 6f is inclined in such a manner that the diameter of the opening end of the conical surface 6f increases as it moves toward the upper surface 4b side. For example, the area of ​​the conical surface 6f when viewed from above is larger than the area of ​​the through hole 6c when viewed from above. The conical surface 6f may also include a curved surface that is a portion where the opening end of the conical surface 6f is chamfered to form a rounded corner.

[0053] Figure 4 for Figure 2 AA line section view. Figure 2 as well as Figure 4 As shown, the seat portion 2 has an inclined surface 7 extending obliquely from the buttocks support portion 4 to the thigh support portion 5. For example, the seat portion 2 has a pair of inclined surfaces 7 arranged along the second direction D2. For example, in a cross section along a plane extending in the first direction D1 and the third direction D3, the inclined surface 7 is linear. The inclination angle θ2 of the inclined surface 7 relative to the lower surface 1b of the core material 1 is, for example, not less than 5° and not more than 15°.

[0054] When the inclination angle θ2 is 5° or more and 15° or less, the ischial bones of the user sitting on the seat portion 2 are less likely to be displaced forward. It should be noted that, unlike the above example, in the cross section along the plane extending in the first direction D1 and the third direction D3, the inclined surface 7 may be curved (for example, a curved surface that is curved so that the inclination angle θ2 increases as it moves toward the thigh support portion 5).

[0055] Figure 5 It is a side view of the core material 1 when viewed from the front. Figure 2 , Figure 4 as well as Figure 5 As shown, the seat section 2 includes a pair of thigh support parts 5 arranged in the second direction D2 and a convex portion 8 located between the pair of thigh support parts 5. The pair of thigh support parts 5 are located on the front side of the inclined surface 7, respectively.

[0056] The thigh support part 5 supports the back side of the thigh of the user. That is, the thigh support part 5 supports the back side of the thigh of the user. Figure 3 as well as Figure 5 As shown, the thigh support portion 5 has a recessed portion 5b that is recessed in the thickness direction (third direction D3) of the core material 1. The recessed portion 5b is formed on the lower surface 1b of the core material 1.

[0057] The core material 1 has a pair of recesses 5b. For example, the pair of recesses 5b are provided at positions separated from each other. The depth of the recess 5b becomes deeper as it moves away from the waist support part 3 (as it moves toward the front side). For example, the thigh support part 5 has a recess 5b that defines a space between the support surface S on which the core material 1 is placed. As an example, the space defined between the recess 5b and the support surface S is formed so as to expand as it moves toward the front.

[0058] The convex portion 8 represents a portion protruding from the inclined surface 7. The width of the convex portion 8 when viewed from above becomes wider as it goes forward. For example, the shape of the convex portion 8 when viewed from above is a parabola shape that becomes wider as it goes forward. The height of the convex portion 8 becomes higher as it goes toward the center of the core material 1 in the second direction D2.

[0059] For example, the seat portion 2 has a pair of convex portions 9 located at both end sides of the inclined surface 7 in the second direction D2. The convex portion 9 is a portion that connects the waist support portion 3 and the thigh support portion 5 to each other. The convex portion 9 extends in the first direction D1. By providing the convex portion 8 and the convex portion 9, the thigh support portion 5 is formed at the corresponding positions on both sides of the convex portion 8 in the second direction D2 between the pair of convex portions 9. Therefore, the thigh of the user can be easily placed on the thigh support portion 5.

[0060] The core material 1 has an inclined portion 9c that is inclined toward the center of the second direction D2 of the core material 1 as it moves from the protrusion 9 toward the lower surface 1b. The core material 1 has, for example, a pair of inclined portions 9c arranged along the second direction D2. As an example, the core material 1 is in a boat shape that extends outward as it moves away from the lower surface 1b.

[0061] The lumbar support portion 3 extends upward from the end portion (rear end) in the first direction D1 of the seat portion 2. The lumbar support portion 3 includes a general portion 10 extending in two directions, for example, the second direction D2 and the third direction D3, and a sacrum support portion 11 located at the center of the general portion 10 in the second direction D2. The general portion 10 indicates a portion of the lumbar support portion 3 excluding the sacrum support portion 11.

[0062] like Figure 2 , Figure 4 as well as Figure 5 As shown, the sacrum support portion 11 is convex and protrudes forward. The sacrum support portion 11 protrudes forward from the general portion 10. As an example, the shape of the sacrum support portion 11 seen from the front has a long axis and a short axis. For example, the shape of the sacrum support portion 11 seen from the front is an oblong (as an example, an ellipse).

[0063] For example, the sacrum support portion 11 has a protruding surface 11d that is a curved surface that protrudes forward. The height of the protruding surface 11d relative to the general portion 10 increases as it moves from the outer edge of the protruding surface 11d toward the inner side of the protruding surface 11d. The sacrum support portion 11 may also have a recessed portion 11f that is recessed backward from the protruding surface 11d. The recessed portion 11f is a portion into which the sacrum of the user of the seat cushion 100 enters.

[0064] The recessed portion 11f extends in the second direction D2 and the third direction D3. For example, the length of the recessed portion 11f in the third direction D3 is greater than the length (width) of the recessed portion 11f in the second direction D2. The shape of the recessed portion 11f viewed from the first direction D1 may be a groove (or an oblong) extending along the third direction D3.

[0065] The recessed portion 11f includes a bottom surface 11g and an inner side surface 11h connecting the bottom surface 11g and the protruding surface 11d. When viewed from the first direction D1, the inner side surface 11h is annular around the bottom surface 11g. The inner side surface 11h may include an R surface connecting the bottom surface 11g and the protruding surface 11d.

[0066] In a plan view, the bottom surface 11g is curved so as to be recessed rearward as it moves away from the end portion of the recessed portion 11f in the second direction D2. In a section (side section) orthogonal to the second direction D2, the recessed portion 11f (bottom surface 11g) is curved so as to be recessed rearward as it moves away from the end portion of the recessed portion 11f in the third direction D3.

[0067] The posture detection system 30 according to this embodiment (see Figure 7 ) detects the posture of a user sitting on the seat portion 2 of the seat cushion 100. The posture detection system 30 includes a seat portion sensor 31 installed on the seat portion 2, a sacrum support portion sensor 32 installed on the sacrum support portion 11, and a thigh support portion sensor 33 installed on the thigh support portion 5. Figure 1 , Figure 2 , Figure 4 as well as Figure 5 In FIG. 1 , the seat portion sensor 31 , the sacrum support portion sensor 32 , and the thigh support portion sensor 33 are simplified in illustration.

[0068] As an example, the core material 1 has a recessed portion formed on the upper surface of the seat portion 2 and a recessed portion formed on the upper surface of the thigh support portion 5, a seat sensor 31 is embedded in the recessed portion of the seat portion 2, and a thigh support portion sensor 33 is embedded in the recessed portion of the thigh support portion 5. For example, a sacrum support portion sensor 32 is mounted in the recessed portion 11f of the sacrum support portion 11.

[0069] As described above, as an example, the seat sensor 31, the sacrum support sensor 32, and the thigh support sensor 33 are directly attached to the core material 1. However, at least any one of the seat sensor 31, the sacrum support sensor 32, and the thigh support sensor 33 may be indirectly attached to the core material 1. Hereinafter, an example in which the seat sensor 31, the sacrum support sensor 32, and the thigh support sensor 33 are indirectly attached to the core material 1 will be described.

[0070] Figure 6Schematically shows a cross-sectional view of a seat cushion 100 having a core material 1 and a fabric 20 covering the core material 1. Figure 6 In the figure, the core material 1 and the like are simplified. As described above, the seat cushion 100 is used by accommodating the core material 1 in the fabric 20. Figure 6 In the example of FIG. 1 , the posture detection system 30 of the present embodiment includes a seat sensor 31 , a sacrum support sensor 32 , and a thigh support sensor 33 .

[0071] For example, the fabric 20 is an inner fabric to which the seat sensor 31, the sacrum support sensor 32, and the thigh support sensor 33 are mounted. That is, the fabric 20 is a sensor fabric to which the seat sensor 31, the sacrum support sensor 32, and the thigh support sensor 33 are fixed. The seat cushion 100 further includes an outer fabric 22 covering the fabric 20 as the inner fabric. The fabric 20 as the inner fabric, for example, covers only a portion of the core material 1. As a specific example, the fabric 20 is fixed to the core material 1 in such a manner as to cover only the seat part 2 and the sacrum support part 11.

[0072] The seat sensor 31, the sacrum support sensor 32, and the thigh support sensor 33 are fixed to the fabric 20. The seat sensor 31, the sacrum support sensor 32, and the thigh support sensor 33 are, for example, piezoelectric sensors fixed to the fabric 20. In this case, the seat sensor 31, the sacrum support sensor 32, and the thigh support sensor 33 respectively measure the pressure of the body of the user carried on the seat cushion 100 on each part of the seat cushion 100.

[0073] The type of each of the seat sensor 31, the sacrum support sensor 32, and the thigh support sensor 33 is not particularly limited. For example, at least one of the seat sensor 31, the sacrum support sensor 32, and the thigh support sensor 33 may be a strain sensor (or strain gauge) that measures the surface strain of the core material 1.

[0074] For example, the seat sensor 31, the sacrum support sensor 32, and the thigh support sensor 33 may be linear sensors fixed to the fabric 20 by embroidery. When the fabric 20 covers the core material 1, the seat sensor 31 is located on the upper surface of the seat 2, the sacrum support sensor 32 is located on the sacrum support part 11, and the thigh support sensor 33 is located on the thigh support part 5.

[0075] The outer fabric 22 covers the core material 1 and the fabric 20. The outer fabric 22 covers the entire core material 1 and the fabric 20, for example. The outer fabric 22 is provided, for example, to prevent the fabric 20 and the core material 1 from being soiled. The outer fabric 22 can be attached and detached relative to the core material 1 and the fabric 20. As an example, the outer fabric 22 can have a fastener (not shown), and the core material 1 and the fabric 20 can be freely taken out or put in relative to the inside of the outer fabric 22 after the fastener is opened. In this case, the outer fabric 22 can be removed from the core material 1 and the fabric 20 and washed.

[0076] like Figure 1 as well as Figure 6 As shown, as an example, the posture detection system 30 includes two seat sensors 31 arranged along the second direction D2, one sacrum support sensor 32, and two thigh support sensors 33 arranged along the second direction D2. The seat sensor 31 is, for example, arranged around each of a pair of ischium supports 6. As an example, the seat sensor 31 is arranged between the ischium support 6 and the vent 2b. In addition, the seat sensor 31 may be arranged on the buttocks support 4. In this case, the seat sensor 31 detects the contact between the user's buttocks and the buttocks support 4.

[0077] For example, the sacrum support sensor 32 is fixed to the bottom surface 11g of the recessed portion 11f. However, the sacrum support sensor 32 may be fixed to the inner side surface 11h of the recessed portion 11f, or to the protruding surface 11d of the sacrum support portion 11. The sacrum support sensor 32 may be provided on the inner side of the outer edge of the sacrum support portion 11 when viewed along the first direction D1. For example, the sacrum support sensor 32 measures the load of the user's sacrum on the sacrum support portion 11.

[0078] A pair of thigh support sensors 33 are respectively fixed to the front side portions of the ventilation holes 2b in the thigh support 5. The thigh support sensors 33 may be arranged on both sides of the convex portion 8 in the second direction D2. The thigh support sensors 33 may be arranged on the inner side of the thigh support 5 when viewed in the third direction D3. For example, the thigh support sensors 33 measure the load of the user's thigh on the thigh support 5.

[0079] For example, the seat sensor 31 detects whether the user of the seat cushion 100 is sitting on the seat 2. The seat sensor 31 detects, for example, whether the user's ischial bones are in contact with the seat. In the above description, an example in which the number of seat sensors 31 is two is described. However, the number of seat sensors 31 may be one or three or more, without particular limitation.

[0080] For example, the sacrum support sensor 32 detects the posture of the user of the seat cushion 100 sitting on the seat portion 2. The sacrum support sensor 32 detects, for example, whether the sacrum of the user is in contact with the sacrum support sensor 32, and measures the load of the user's body in contact with the sacrum support sensor 32. For example, the thigh support sensor 33 measures the load of the thigh of the user of the seat cushion 100 sitting on the seat portion 2.

[0081] As an example, the posture detection system 30 includes a cable 34 and a communication unit 35. The cable 34 is electrically connected to the seat sensor 31, the sacrum support sensor 32, and the thigh support sensor 33, and extends from the fabric 20 to the outside of the fabric 20. The communication unit 35 is provided on the side of the cable 34 opposite to the fabric 20.

[0082] The communication unit 35 is, for example, a communication substrate for communicating the measurement data of the seat sensor 31, the measurement data of the sacrum support sensor 32, and the measurement data of the thigh support sensor 33. The communication unit 35 receives the measurement data of the seat sensor 31, the measurement data of the sacrum support sensor 32, and the measurement data of the thigh support sensor 33 via the cable 34. The cable 34 may be omitted, and the communication unit 35 may be built into the fabric 20.

[0083] Figure 7 is a block diagram showing the functional structure of the posture detection system 30. Figure 7 The posture detection system 30 includes a control unit 40 and an output unit 50. As an example, the control unit 40 is a server. The seat sensor 31, the sacrum support sensor 32, and the thigh support sensor 33 can communicate with the control unit 40.

[0084] The seat sensor 31, the sacrum support sensor 32, and the thigh support sensor 33 transmit the measurement data obtained by the measurement to the control unit 40 via the communication unit 35. The control unit 40 includes a processor (e.g., a CPU (central processing unit)) that executes an operating system and an application program, a main storage unit composed of a ROM (read only memory) and a RAM (random access memory), an auxiliary storage unit composed of a hard disk or a flash memory, and a communication control unit composed of a network card or a wireless communication module. However, the configuration of the control unit 40 is not limited to the above configuration, and can be appropriately changed.

[0085] Each functional element of the control unit 40 is realized by reading the specified software into the processor or the main storage unit and executing the software. The processor operates the above-mentioned communication control unit according to the software to read and write data in the main storage unit or the auxiliary storage unit. The data or database required for the processing of the control unit 40 is stored in the main storage unit or the auxiliary storage unit.

[0086] The control unit 40 may include a posture detection program. The posture detection program includes, for example, a main module, a data acquisition module, an analysis module, and an output module. The main module is a module that uniformly manages the functions of the posture detection system 30. The data acquisition module acquires measurement data from the seat sensor 31, the sacrum support sensor 32, and the thigh support sensor 33, respectively. The calculation module evaluates the sitting state and posture of the user of the seat cushion 100 by calculation based on the measurement data. The output module outputs the result calculated by the calculation module.

[0087] The functional structural elements of the posture detection system 30 (posture detection program) function by executing the data acquisition module, the calculation module, and the output module. The posture detection program can be stored in a recording medium such as a CD-ROM, a DVD-ROM, or a semiconductor memory and provided. The posture detection program can be provided as a data signal superimposed on a carrier via a communication network.

[0088] As an example, the posture detection system 30 has a posture data analysis tool. The posture detection system 30 collects, analyzes, and visualizes the measurement data for each specified time (e.g., 1 hour or 1 day) using, for example, spreadsheet software. For example, the posture detection system 30 visualizes the data of the user's sitting time, sitting frequency, and posture on the cushion 100. In this case, the user can easily grasp the sitting time, sitting frequency, and posture on the cushion 100. Therefore, the user can be urged to improve his posture.

[0089] For example, the control unit 40 includes a sitting determination unit 41 and a posture determination unit 42 as functional structural elements. The control unit 40 may include a leg crossing determination unit 43 for determining whether the legs of the user sitting on the seat unit 2 are crossed. The sitting determination unit 41, the posture determination unit 42, and the leg crossing determination unit 43 are functions implemented by, for example, a program installed in the control unit 40.

[0090] The sitting determination unit 41 determines whether the user is sitting on the seat unit 2. The sitting determination unit 41 measures the time the user is sitting on the seat unit 2. The sitting determination unit 41 determines whether the user is sitting on the seat unit 2 using measurement data from the seat unit sensor 31, for example.

[0091] The sitting determination unit 41 determines that the user is sitting on the seat 2 when, for example, the user's body (e.g., buttocks or ischial tuberosity) contacts the seat sensor 31. When a plurality of seat sensors 31 are provided, the sitting determination unit 41 can determine that the user is sitting on the seat 2 when the user's body contacts any one of the plurality of seat sensors 31.

[0092] The posture determination unit 42 determines the posture of the user sitting on the seat unit 2. The posture determination unit 42 determines the posture of the user based on the result measured by the sacrum support sensor 32. For example, when the user's body (e.g., sacrum) is not in contact with the sacrum support sensor 32, the posture determination unit 42 determines that the user's posture is slouched (hunched), which is inappropriate.

[0093] The posture determination unit 42 measures the hunched time. When the posture is hunched, the posture is bent forward and the sacrum is not in contact with the sacrum support sensor 32. The posture determination unit 42 determines that the posture is hunched when the sitting determination unit 41 determines that the user is sitting on the seat unit 2 and the sacrum is not in contact with the sacrum support sensor 32.

[0094] The posture determination unit 42 determines that the user's posture is leaning too far backward, for example, when the load measured by the sacrum support part sensor 32 is greater than a certain value. The posture determination unit 42 measures the time of excessive backward leaning. When leaning too far backward, a larger load in the rear direction is applied to the sacrum support part sensor 32 than when the posture is appropriate. When the sacrum support part sensor 32 measures this load, the posture determination unit 42 determines that the posture is leaning too far backward and is inappropriate. For example, the sacrum support part sensor 32 can measure the deformation amount (degree of collapse) of the sacrum support part 11, and the posture determination unit 42 can determine that the posture is leaning too far backward when the measured deformation amount of the sacrum support part 11 is greater than a certain value.

[0095] The posture determination unit 42 determines that the user's posture is appropriate, for example, when the load measured by the sacrum support part sensor 32 does not reach a certain value. The posture determination unit 42 measures the time when the posture is appropriate. When the posture is appropriate, the back of the user sitting on the seat part 2 extends in the vertical direction, and the sacrum support part 11 receives an appropriate load from the sacrum. When the sacrum support part sensor 32 measures the appropriate load, the posture determination unit 42 determines that the posture is appropriate. As above, the posture determination unit 42 can determine that the posture is appropriate when the measured deformation amount of the sacrum support part 11 does not reach a certain value.

[0096] The posture determination unit 42 may calculate the difference between the loads on the thigh support sensors 33 measured by the pair of thigh support sensors 33. In this case, the posture determination unit 42 calculates the absolute value of the difference between the load on one thigh support sensor 33 received from the left thigh and the load on the other thigh support sensor 33 received from the right thigh.

[0097] Then, the posture determination unit 42 may determine that the left-right balance is poor and the posture is inappropriate when the calculated absolute value is greater than a certain value, and may determine that the left-right balance is good when the calculated absolute value is not greater than the certain value. In this case, it is possible to understand whether the posture of the user sitting on the seat unit 2 is biased to either the left or the right. For example, the posture determination unit 42 measures the time of the left-right balance being poor.

[0098] The leg crossing determination unit 43 determines whether the user sitting on the seat unit 2 has crossed legs. For example, the leg crossing determination unit 43 uses the measurement data from the thigh support sensor 33 to determine whether the user has crossed legs. The leg crossing determination unit 43 measures the time when the user's legs are crossed. As a specific example, when one of the pair of thigh support sensors 33 receives a load from the thigh, and the other thigh support sensor 33 does not receive a load from the thigh, the leg crossing determination unit 43 determines that the user's legs are crossed.

[0099] In addition, owing to if sitting for a long time under the state of legs crossed, pelvis may be deformed, therefore not preferably.In the present embodiment, the legs crossing determining unit 43 determines whether the user sitting on the seat portion 2 crosses legs, thus can notify the user preferably not to cross legs for a long time.

[0100] The output unit 50 outputs the results determined by the sitting determination unit 41 and the posture determination unit 42. The output unit 50 may also output the result determined by the leg crossing determination unit 43. The output unit 50 includes, for example, a display unit 51 that displays the result of the determination, and an alarm unit 52 that outputs an alarm when the posture determination unit 42 determines that the posture is inappropriate (for example, when the posture is determined to be hunched, leaning too far backward, or leaning to one side or the other).

[0101] like Figure 7 as well as Figure 8 As shown, the display unit 51 displays the determination results of the sitting determination unit 41, the posture determination unit 42, and the leg crossing determination unit 43 on the display of the information terminal T, for example. The information terminal T is, for example, a portable terminal. The "portable terminal" refers to a portable information terminal such as a portable phone including a smartphone, a tablet computer, or a notebook computer. The information terminal may also be a terminal other than a portable terminal, for example, a personal computer.

[0102] The display unit 51 displays, for example, the sitting time 51b on the seat unit 2 detected by the sitting determination unit 41 and the time 51c of the proper posture detected by the posture determination unit 42. The display unit 51 may also display the time 51d of hunching detected by the posture determination unit 42 and the time 51f of excessive backward leaning detected by the posture determination unit 42. Furthermore, the display unit 51 may also display the time 51g of left-right imbalance detected by the posture determination unit 42 and the time 51h of both legs being crossed detected by the leg crossing determination unit 43.

[0103] The display unit 51 can display at least one of the sitting time on the seat unit 2, the time of proper posture, the time of hunching, the time of excessively leaning backward, the time of poor balance between left and right, and the time of crossing legs as a time graph 51j. In this case, the above-mentioned times can be clearly understood by simply viewing the time graph 51j. Therefore, the user can understand his or her sitting posture habits for the seat cushion 100, and can prevent problems such as waist and leg injuries by correcting bad sitting postures.

[0104] The display unit 51 may display the determination result of the sitting determination unit 41 and the determination result of the posture determination unit 42 as comments 51k. Furthermore, the display unit 51 may display the determination result of the leg crossing determination unit 43 as comments 51k. Furthermore, the display unit 51 may display the determination result of the sitting determination unit 41 and the determination result of the posture determination unit 42 as ratings 51p (evaluations).

[0105] For example, the comments 51k include "You have been sitting for too long, I suggest you stand up and do some exercise", "You often sit with your back hunched, please sit with your back straight", "You have been leaning back for a long time, please suck in your stomach and straighten your back", "Please pay attention to left and right balance when sitting", "Please reduce the time of crossing your legs", or "You are sitting in the correct posture", etc. The user can learn how to sit on the cushion 100 for health benefits by viewing the comments 51k.

[0106] The alarm unit 52 outputs an alarm when the posture determination unit 42 determines that the posture is inappropriate. For example, when the posture determination unit 42 determines that the posture is inappropriate, the alarm unit 52 notifies the user's information terminal T of an alarm. The alarm may be notified by e-mail or by an application.

[0107] The alarm unit 52 outputs an alarm when, for example, any one of the sitting time on the seat portion 2, the time of hunching, the time of leaning too far backward, the time of poor balance on the left and right, and the time of crossing the legs is for a certain time or longer. As an example, the alarm unit 52 may be a lamp installed on the cushion 100. In this case, the user can easily grasp the state of sitting for a long time or poor posture by observing the lamp of the cushion 100 on which he / she sat. The alarm unit 52 may also output a sound when any one of the sitting time on the seat portion 2, the time of hunching, the time of leaning too far backward, the time of poor balance on the left and right, and the time of crossing the legs is for a certain time or longer.

[0108] Next, a specific example of the posture detection method involved in this embodiment is described. Figure 6 The method of adjusting the posture of a user sitting on the seat cushion 100 shown in FIG. 1 is described below. For example, the fabric 20 is fixed to the core material 1 so that the positions of the seat sensor 31, the sacrum support sensor 32, and the thigh support sensor 33 match the positions of the buttocks support 4, the sacrum support 11, and the thigh support 5. Then, the core material 1 and the fabric 20 are stored inside the outer fabric 22.

[0109] The seat sensor 31 mounted on the seat 2 detects whether the user is sitting on the seat 2 (a process in which the seat sensor performs detection). For example, the seat sensor 31 detects whether the buttocks are in contact with the seat sensor 31, and the sitting determination unit 41 determines whether the user is sitting on the seat 2.

[0110] In addition, the sacrum support sensor 32 detects the posture of the user sitting on the seat part 2 (a process of detecting by the sacrum support sensor). The sacrum support sensor 32 detects whether the sacrum is in contact with the sacrum support sensor 32, and measures the load of the sacrum on the sacrum support sensor 32. For example, the posture determination unit 42 determines that the posture is hunched when the sacrum is not in contact with the sacrum support sensor 32, determines that the posture is excessively leaning backward when the load on the sacrum support sensor 32 is greater than a certain value, and determines that the posture is appropriate when the load on the sacrum support sensor 32 is not greater than the certain value (a process of determining). The pair of thigh support sensors 33 can measure the load from the thigh, and the posture determination unit 42 can determine whether the left and right balance is appropriate. The leg crossing determination unit 43 can determine whether the user's legs are crossed based on the measurement results of the pair of thigh support sensors 33.

[0111] When the posture determination unit 42 determines that the user's posture is good, for example, the display unit 51 displays that the user's posture is correct, and a series of processes are completed. When the posture determination unit 42 determines that the user's posture is bad, the alarm unit 52 outputs an alarm (a process of outputting an alarm). Specifically, the alarm unit 52 can notify the information terminal T of the inappropriate posture, or it can make the light of the seat cushion 100 light up. The alarm unit 52 can notify the user of the inappropriate posture by vibration. In this case, the alarm unit 52, for example, makes the seat cushion 100 on which the user is sitting vibrate. After the notification of the alarm unit 52 is completed, a series of processes of the posture detection method are completed.

[0112] Next, the effects obtained by the posture detection system 30 and the posture detection method according to the present embodiment will be described in more detail. In the posture detection system 30 and the posture detection method according to the present embodiment, the seat cushion 100 includes a seat portion 2 having a buttocks support portion 4 for supporting the buttocks of the user, and a sacrum support portion 11 for supporting the sacrum of the user from behind. The posture detection system 30 includes a seat portion sensor 31 for detecting whether the user is sitting on the seat portion 2 of the seat cushion 100. By detecting whether the user is sitting on the seat portion 2 by the seat portion sensor 31, the time the user is sitting on the seat portion 2 can be calculated.

[0113] The user can understand whether he / she has been sitting for a long time, so that the problem of poor blood circulation in the waist and legs or decreased muscle strength can be avoided. The posture detection system 30 includes a sacrum support sensor 32 provided in the sacrum support 11 and detecting the posture of the user sitting on the seat cushion 100. The sacrum is a part protruding from the back of the user. By providing the sacrum support sensor 32 in the sacrum support 11 that supports the sacrum, the posture of the user can be detected with high accuracy.

[0114] The posture detection system 30 includes an alarm unit 52 that outputs an alarm when the posture determination unit 42 determines that the posture is bad. When the posture is bad, the alarm unit 52 outputs an alarm, so that the user can understand that his or her posture is bad. Therefore, the possibility of physical injury due to bad posture can be reduced.

[0115] In the present embodiment, the sacrum support sensor 32 detects whether the sacrum of the user is in contact with the sacrum support sensor 32. The posture determination unit 42 determines that the user's posture is hunched when the sacrum of the user is not in contact with the sacrum support sensor 32. When the user leans forward and the sacrum is not in contact with the sacrum support sensor 32, the posture determination unit 42 determines that the user is hunched. Since the hunched status is determined by the presence or absence of contact with the sacrum support sensor 32, the user's posture can be grasped with high accuracy and the hunched status can be suppressed.

[0116] In the present embodiment, the sacrum support sensor 32 measures the load of the sacrum of the user on the sacrum support sensor 32. When the load measured by the sacrum support sensor 32 is greater than a certain value, the posture determination unit 42 determines that the posture of the user is leaning too far backward. When the load on the sacrum support sensor 32 is greater than a certain value, the posture determination unit 42 determines that the posture is leaning too far backward. Since whether or not the user is leaning too far backward is determined by the load on the sacrum support sensor 32, it is possible to suppress a decrease in abdominal muscle strength due to excessive leaning backward.

[0117] In the present embodiment, the seat portion 2 has a pair of thigh support portions 5 arranged in the left-right direction (second direction D2) from the user sitting on the seat portion 2. The posture detection system 30 further includes a pair of thigh support sensors 33 mounted on each of the pair of thigh support portions 5 to measure the load on the thigh of the user sitting on the seat portion 2. The pair of thigh support sensors 33 measure the load on the left and right thighs of the user, respectively, thereby being able to grasp the left-right balance of the thighs. When one of the pair of thigh support sensors 33 detects the load and the other of the pair of thigh support sensors 33 does not detect the load, it is possible to grasp the possibility that the user has crossed his legs. Thus, the posture of the user sitting on the seat cushion 100 can be grasped with higher accuracy.

[0118] In the present embodiment, the posture detection system 30 includes the fabric 20, on which the seat sensor 31 and the sacrum support sensor 32 are mounted, and which covers at least a portion of the core material 1 of the seat cushion 100. In this case, the seat sensor 31 and the sacrum support sensor 32 are mounted on the fabric 20, and at least a portion of the core material 1 is covered by the fabric 20. By covering the core material 1 of the existing seat cushion 100 with the fabric 20, the seat sensor 31 and the sacrum support sensor 32 can be mounted on the seat cushion 100. Therefore, the seat sensor 31 and the sacrum support sensor 32 of the existing seat cushion 100 can be easily arranged.

[0119] In this embodiment, the posture detection system 30 includes the outer fabric 22 covering the core material 1, and the fabric 20 is the inner fabric covered by the outer fabric 22. In this case, the outer fabric 22 is provided outside the inner fabric (fabric 20) to which the seat sensor 31 and the sacrum support sensor 32 are attached. Since the outer fabric 22 can be removed and washed, a more hygienic seat cushion 100 can be obtained, so that the seat cushion 100 can be used continuously for a longer period of time.

[0120] Next, refer to Fig. 9, a seat cushion 200 provided with a posture detection system 60 according to a modified example is described. The seat cushion 200 is different from the above-mentioned seat cushion 100 in that it does not have an inner fabric. The posture detection system 60 and a part of the structure of the seat cushion 200 are the same as the posture detection system 30 and a part of the structure of the seat cushion 100. In the following, the same reference numerals are attached and the description overlapping with the description of the posture detection system 30 and the seat cushion 100 is appropriately omitted.

[0121] The seat cushion 200 is used by accommodating the core material 1 in the fabric 70. The fabric 70 is provided to prevent the core material 1 from being soiled. The fabric 70 is an outer fabric on which the seat sensor 31, the sacrum support sensor 32, and the thigh support sensor 33 are mounted. The fabric 70 as the outer fabric covers the entire core material 1, for example.

[0122] The fabric 70 is detachable from the core 1. For example, the fabric 70 may have a fastener (not shown), and the core 1 may be freely taken out or put in from the inside of the fabric 70 after the fastener is opened. In this case, the seat sensor 31, the sacrum support sensor 32, and the thigh support sensor 33 are detachable from the core 1.

[0123] In this modification, the posture detection system 60 includes a fabric 70, on which at least the seat sensor 31 and the sacrum support sensor 32 are mounted, and which covers at least a portion of the core material 1 of the seat cushion 200. The seat sensor 31 and the sacrum support sensor 32 are mounted on the fabric 70, and the core material 1 is covered by the fabric 70. Since the seat sensor 31 and the sacrum support sensor 32 can be mounted on the seat cushion 200 by covering the core material 1 of the existing seat cushion 200 with the fabric 70, the seat sensor 31 and the sacrum support sensor 32 of the existing seat cushion 200 can be easily arranged. In this modification, the same effects as those of the above-mentioned embodiment can be obtained.

[0124] The above describes the embodiments of the posture detection system and the posture detection method involved in the present invention. However, the posture detection system and the posture detection method involved in the present invention are not limited to the above embodiments, and can be modified or applied to other embodiments without changing the main points described in the scope of the claims. The structure and function of each part of the posture detection system, as well as the process content and sequence of the posture detection method can be appropriately changed without changing the above main points. The shape, size, number, material and configuration of each part of the seat cushion are not limited to the above-mentioned seat cushions 100 and 200, and can be appropriately changed.

[0125] For example, in the above-mentioned embodiment, an example in which the thigh support sensor 33 measures the load on the thigh is described. However, the thigh support sensor 33 may be omitted. In the above-mentioned embodiment, the core material 1 having the seat portion 2 and the lumbar support portion 3 is described. For example, the height of the lumbar support portion 3 may be appropriately changed. For example, the height of the upper end of the lumbar support portion 3 may be the height of the user's back, the height of the user's shoulders, or the height of the user's head, and is not particularly limited. In this case, the seat cushion can be used as a chair such as a gaming chair.

[0126] For example, in the above embodiment, an example is described in which the alarm unit 52 notifies the information terminal T of an inappropriate posture. However, for example, the alarm unit may output the alarm in the form of sound. The alarm unit may also output the alarm in the form of light. The alarm unit may also output the alarm in the form of vibration. In this way, the type of alarm output by the alarm unit may be appropriately changed.

[0127] For example, the seat cushion may be a seat cushion in which the lumbar support portion can be folded relative to the seat portion. In this case, the seat cushion may be used as an office chair, a reclining chair, or a full flat seat. The seat cushion may be a seat for a transportation vehicle such as a car, a railway vehicle, or an airplane. In this way, the posture detection system and posture detection method of the present invention may be applied to various seat cushions.

[0128] Hereinafter, a modified example of a seat cushion to which the posture detection system and the posture detection method can be applied will be described. In this modified example, in addition to the seat cushion body, a lumbar support is also provided. The lumbar support and the seat cushion are made of a flexible material. "Flexible material" refers to a cushioning material that deforms when supporting a body and bearing a load. As an example, the lumbar support and the seat cushion are placed on a chair. The "chair" is a seat for a user of the lumbar support and the seat cushion.

[0129] The "lumbar support" is used to support the waist (lumbar vertebrae) of the user. For example, by inserting the lumbar support between the backrest of the chair and the waist of the user, the waist of the user sitting on the chair can be supported by the lumbar support. The "user" refers to the user of the lumbar support or the cushion, for example, a person who installs the lumbar support behind the waist or a person who sits on the cushion.

[0130] Fig.10 1 is a front view showing the lumbar support 120 and the seat cushion 101. The seat cushion 101 includes the lumbar support 120 and a seat cushion portion 110 located below the lumbar support 120 and having a seat portion 111 on which a user sits.

[0131] First, the cushion portion 110 will be described. Fig.10As shown, the cushion portion 110 includes a seat portion 111 extending in the horizontal direction and a lumbar support portion 112 extending upward from the seat portion 111. The cushion portion 110 is made of a flexible material, for example, polyurethane foam.

[0132] As an example, the cushion portion 110 is formed by polyurethane mold molding. When the cushion portion 110 is formed by polyurethane mold molding composed of polyurethane foam, the cushion portion 110 composed of a flexible material can be easily manufactured. The cushion portion 110 is, for example, stored in a shell fabric for use.

[0133] It should be noted that the above-mentioned flexible material may include, for example, a thermoplastic elastomer. The flexible material may be a material having elasticity to the extent that it deforms according to the load when the body is supported. The flexible material may be a resin (for example, polypropylene, polyester, or polyethylene) that deforms when the body is supported and subjected to the load. The type of the flexible material may be appropriately changed.

[0134] Fig.11 1 is a top view showing the seat cushion 101. Fig.10 as well as Fig.11 As shown, the seat portion 111 extends in a first direction A1 and a second direction A2 intersecting the first direction A1. The first direction A1 is a left-right direction when viewed from a user sitting on the seat portion 111, and the second direction A2 is a front-back direction when viewed from a user sitting on the seat portion 111. The seat portion 111 has a thickness in a third direction A3 intersecting the first direction A1 and the second direction A2. For example, the third direction A3 is a vertical direction.

[0135] Hereinafter, the forward direction when viewed from the user sitting on the seat portion 111 is sometimes referred to as "front", "front side" or "front", and the direction opposite to the forward direction is sometimes referred to as "rear", "rear side" or "rear". However, these directions are for convenience of description and do not limit the positions or directions of the various parts.

[0136] The seat portion 111 includes a buttocks support portion 113 for supporting the buttocks of the user, and a thigh support portion 114 for supporting the thighs of the user. The buttocks support portion 113 and the thigh support portion 114 are arranged side by side along the second direction A2. The buttocks support portion 113 includes a pair of ischium support portions 115 for supporting the ischium of the user sitting on the seat portion 111.

[0137] For example, the seat portion 111 has a vent hole 111b. The vent hole 111b is formed, for example, on the upper surface of the buttocks support portion 113 and the upper surface of the thigh support portion 114. The vent hole 111b penetrates the seat portion 111, for example, along the third direction A3. The upper end of the inner wall defining the vent hole 111b may be rounded to form a rounded corner. In a plan view, the plurality of vent holes 111b are arranged from the rear to the front.

[0138] For example, in a plan view (a plan view in which the lumbar support portion 112 is located above the seat portion 111), a plurality of (for example, six) ventilation holes 111b may be disposed on both sides (left and right sides) in the first direction A1. For example, three ventilation holes 111b are formed on both sides in the first direction A1.

[0139] For example, two ventilation holes 111b are arranged along the first direction A1, and the distance between the two ventilation holes 111b arranged along the first direction A1 increases as the distance increases from the buttocks support part 113 toward the thigh support part 114 (as the distance increases toward the front). As an example, the plurality of ventilation holes 111b are arranged in an "eight" shape when viewed from above.

[0140] For example, in the cushion portion 110, the ischial support portion 115 is formed by polyurethane mold molding, and the vent hole 111b is formed by die cutting. In this case, since the portion where the vent hole 111b is formed is not required in the mold used when manufacturing the cushion portion 110, the shape of the mold can be simplified. When liquid polyurethane is molded in the mold, an escape path for air in the liquid polyurethane can be ensured, so the finished product of the cushion portion 110 can be made smooth.

[0141] The ischium support portion 115 is formed on the upper surface of the buttocks support portion 113 and is recessed in the buttocks support portion 113. The buttocks support portion 113 has a pair of ischium support portions 115 arranged along the first direction A1. The ischium support portion 115 has a recessed portion recessed from the upper surface of the buttocks support portion 113. The shape of the ischium support portion 115 when viewed from above is set to have a major axis and a minor axis. For example, the shape of the ischium support portion 115 when viewed from above is an oblong (as an example, an ellipse). However, the shape of the ischium support portion 115 when viewed from above is not limited to an oblong or an ellipse, and may also be a rectangle, a rounded rectangle, a rhombus, or a rounded rhombus, and may be appropriately changed.

[0142] The intersection point where the extended line of the long axis of one of the pair of ischium support portions 115 intersects with the extended line of the long axis of the other of the pair of ischium support portions 115 is located closer to the thigh support portion 114 (closer to the front) than the pair of ischium support portions 115. Thus, the pair of ischium support portions 115 form an inverted figure eight shape in a plan view (a plan view in which the lumbar support portion 112 is located on the upper side of the seat portion 111).

[0143] The ischium support portion 115 may include a through hole that penetrates the buttocks support portion 113 in the third direction A3. In this case, the ischium support portion 115 includes an inner wall that defines the through hole and a tapered surface between the inner wall and the upper surface of the buttocks support portion 113. For example, the area of ​​the ischium support portion 115 when viewed from above is larger than the area of ​​the ischium support portion 115 when viewed from below.

[0144] The seat portion 111 may have an inclined surface extending obliquely from the buttocks support portion 113 toward the thigh support portion 114. The inclined surface extends obliquely upward from the buttocks support portion 113 toward the thigh support portion 114. The inclined surface is inclined with respect to the second direction A2 in such a manner that the seat portion 111 becomes thicker as it moves from the buttocks support portion 113 toward the thigh support portion 114. The seat portion 111 has a pair of thigh support portions 114 arranged in the first direction A1, and a convex portion 116 located between the pair of thigh support portions 114. The convex portion 116 indicates a portion protruding upward between the pair of thigh support portions 114.

[0145] The rear side of the thigh of the user is supported on the thigh support portion 114. The thigh support portion 114 supports the rear side of the thigh of the user. For example, the thigh support portion 114 has a recessed portion that is recessed in the thickness direction (third direction A3) of the cushion portion 110. For example, recesses of the thigh support portion 114 are respectively formed on the upper surface and the lower surface of the cushion portion 110. For example, the recess formed on the lower surface of the cushion portion 110 in the thigh support portion 114 defines a space between the surface on which the cushion 101 is placed, i.e., the placement surface. Through this space, when the thigh support portion 114 supports the thigh, the thigh support portion 114 can be easily sunk.

[0146] The lumbar support portion 112 extends upward from the end portion (rear end) of the seat portion 111 in the second direction A2. The lumbar support portion 112 includes, for example, a sacrum support portion 119 located in the center in the first direction A1. The sacrum support portion 119 is convex and protrudes forward. That is, the sacrum support portion 119 protrudes forward at the lumbar support portion 112. As an example, the shape of the sacrum support portion 119 seen from the front is a shape having a major axis and a minor axis. For example, the shape of the sacrum support portion 119 seen from the front is an oblong (as an example, an elliptical).

[0147] For example, the sacrum support part 119 has a protruding surface 119b that is a curved surface that protrudes forward. The height of the protruding surface 119b relative to the front surface of the lumbar support part 112 increases as it moves from the outer edge of the protruding surface 119b toward the inner side of the protruding surface 119b. For example, the sacrum support part 119 may also have a recessed part 119c that is recessed backward from the protruding surface 119b. The recessed part 119c is a portion of the seat cushion 101 into which the sacrum of the user enters.

[0148] The recessed portion 119c extends in the first direction A1 and the third direction A3. For example, the length of the recessed portion 119c in the third direction A3 is greater than the length (width) of the recessed portion 119c in the first direction A1. The shape of the recessed portion 119c viewed along the second direction A2 may be a groove (or an oblong) extending in the third direction A3.

[0149] The seat portion 111 has a pair of convex portions 117 located at both ends of the first direction A1 when viewed from the thigh support portion 114. The convex portion 117 extends from each of the thigh support portions 114 to the waist support portion 112. Fig.10 as well as Fig.12 As shown, the convex portion 117 extends from both end sides of the thigh support portion 114 in the first direction A1 toward the waist support portion 112 .

[0150] The convex portion 117 is curved in a manner that bulges upward as it moves toward the center of the first direction A1 at the waist support portion 112. When viewed in the second direction A2, the height of the convex portion 117 relative to the thigh support portion 114 becomes higher as it approaches the center of the first direction A1. For example, when viewed in the second direction A2, the convex portion 117 has a mountain shape (or an inverted U shape).

[0151] In the seat cushion 101, a lumbar support member 120 is placed on the convex portion 117 of the seat cushion portion 110. The lower surface of the lumbar support member 120 is curved so as to be concave upward toward the center in the first direction A1. When viewed in the second direction A2, the height of the lower surface of the lumbar support member 120 becomes higher as it approaches the center in the first direction A1. For example, when viewed in the second direction A2, the lower surface of the lumbar support member 120 has a mountain shape (or an inverted U shape).

[0152] The shape of the lower surface of the lumbar support 120 is set to imitate the shape of the upper surface of the convex portion 117. By making the lower surface of the lumbar support 120 contact the upper surface of the convex portion 117 of the seat cushion portion 110, the lumbar support 120 can be easily placed on the seat cushion portion 110. The lumbar support 120 can also be easily removed from the seat cushion portion 110. The lumbar support 120 can be used together with the seat cushion portion 110, or the lumbar support 120 can be used alone. The lumbar support 120 can be tied to the backrest of the chair, and the lumbar support 120 can be used in a state of being tied to the chair.

[0153] Next, we will refer to Fig.11 , Fig.12 as well as Fig.13 The lumbar support 120 will be described. Fig.13 1 is a front view showing a lumbar support member 120. The lumbar support member 120 includes a lumbar support portion 121 that supports the lumbar spine of the user from behind, and a pair of side portions 123 that are located on the left and right sides of the user when viewed from the user whose lumbar spine is supported by the lumbar support portion 121. The lumbar support member 120 includes a pair of connecting portions 122 that extend from the lumbar support portion 121 to each of the pair of side portions 123.

[0154] For example, when viewed from above (when viewed from the third direction A3), the lumbar support member 120 is in the shape of an M. In this case, the portion of the center of the M that protrudes downward when viewed from above is the lumbar support portion 121, and the portions of both ends of the M that extend in the vertical direction when viewed from above are the side portions 123. The portion extending from the upper end of each side portion 123 of the M when viewed from above to the lumbar support portion 121 is the connecting portion 122.

[0155] The lumbar support 120 is made of a flexible material. For example, the material of the lumbar support 120 is the same as that of the cushion portion 110. In this case, the lumbar support 120 can be manufactured more easily. For example, the lumbar support 120 is formed by polyurethane mold molding composed of polyurethane foam. The lumbar support 120 is, for example, stored in a shell fabric and used. It should be noted that the lumbar support 120 can be stored in the shell fabric alone or stored in the shell fabric together with the cushion portion 110 and used.

[0156] The lumbar support portion 121 is formed in a portion of the lumbar support member 120 including the center in the first direction A1. The lumbar support portion 121 is convex and protrudes forward. The lumbar support portion 121 protrudes forward from the front surface (the surface facing the front side) of the lumbar support member 120. For example, the lumbar support portion 121 includes a protrusion 121b that protrudes toward the back of the user, and a first concave portion 121c that is concave from the protrusion 121b and extends along the third direction A3 that is the height direction of the user's body.

[0157] For example, the protrusion 121b is in the shape of a curved surface that protrudes forward. The protrusion height of the protrusion 121b on the front surface of the lumbar support 120 increases as it approaches the center of the lumbar support 120 in the first direction A1. The first recess 121c is a portion that is recessed backward from the protrusion 121b. When the lumbar support 120 is placed on the cushion portion 110, the lumbar vertebra support portion 121 is located directly above the sacrum support portion 119.

[0158] The first recess 121c is a portion of the lumbar support 120 into which the lumbar vertebra of the user enters. By visually recognizing the first recess 121c, the user can easily understand that the lumbar support 120 only needs to be installed so that the lumbar vertebra enters the first recess 121c. The first recess 121c can be used as a mark of the lumbar vertebra support portion 121. The same is true for the recessed portion 119c of the sacrum support portion 119.

[0159] In a plan view (when the lumbar support 120 is viewed along the third direction A3 in which the lumbar support 120 appears to be in an M shape), the connection portion 122 extends obliquely upward from the lumbar support portion 121. From the perspective of a user whose lumbar spine is supported by the lumbar support portion 121, the pair of connection portions 122 extend obliquely backward from the lumbar support portion 121.

[0160] The connecting portion 122 is plate-shaped when viewed from above. For example, the thickness of the connecting portion 122 when viewed from above is smaller than the thickness of the side portion 123 when viewed from above. As an example, the thickness of the connecting portion 122 when viewed from above is smaller than the thickness of the portion other than the connecting portion 122 when viewed from above. The lumbar vertebra support portion 121 and the connecting portion 122 can be easily deformed.

[0161] In this embodiment, the lumbar support 120 has a pair of tops 126 located at the rear end of each connection portion 122. The tops 126 are located at the end portion on the opposite side of the lumbar support portion 121 when viewed from the connection portion 122. When the user wears the lumbar support 120, the height of the connection portion 122 increases as it moves away from the lumbar support portion 121, and the height of the tops 126 is the highest. The pair of tops 126 corresponds to a pair of protrusions located at the upper end of the M-shaped lumbar support 120 in a plan view.

[0162] The side portion 123 is a portion extending forward from the top portion 126. The pair of side portions 123 each has an inner side surface 123b facing the user. Each side portion 123 has an ilium-facing portion 124 facing the ilium of the user. In a plan view, an inclined surface extending obliquely forward from the ilium-facing portion 124 and an end surface located on the opposite side of the ilium-facing portion 124 as viewed from the inclined surface are formed at the end of the ilium-facing portion 124 on the side opposite to the top portion 126.

[0163] For example, the ilium-facing portion 124 includes an ilium support portion 124c that protrudes from the inner side surface 123b and supports the ilium of the user, and a second recessed portion 124b that is recessed from the ilium support portion 124c. For example, the ilium support portion 124c has a curved surface that protrudes toward the inner side of the lumbar support member 120 when viewed from above. For example, the second recessed portion 124b is a hole formed in the ilium support portion 124c. As an example, the second recessed portion 124b extends in a direction that is inclined with respect to both the first direction A1 and the second direction A2.

[0164] The second recess 124b is a portion into which at least a portion of the user's ilium enters. By visually recognizing the second recess 124b, the user can easily understand that the lumbar support member 120 only needs to be installed so that the ilium enters the second recess 124b. Similar to the above-mentioned first recess 121c and the like, the second recess 124b can be used as a mark of the ilium supporting portion 124c.

[0165] The pair of side parts 123 each have a rib support part 125 that protrudes from the inner side surface 123b at a position between the lumbar support part 121 and each of the pair of ilium support parts 124c. The rib support part 125 is a portion that supports the lower part of the ribs of the user of the lumbar support member 120. The rib support part 125 protrudes from the inner side surface 123b in a curved shape. When viewed from above, the rib support part 125 protrudes from the inner side surface 123b in an arc shape, for example. For example, the lower end of the ribs of the user is supported by the pair of rib support parts 125.

[0166] Next, the effects obtained from the seat cushion 101 will be described. Fig.14As shown, the lumbar support member 120 has a lumbar support portion 121 that supports the user's lumbar spine from the rear, and a pair of side portions 123 located on the left and right sides of the user, and each side portion 123 is connected to the lumbar support portion 121 through a connection portion 122. The lumbar support member 120 is made of a flexible material, and the pair of connection portions 122 extend obliquely backward from the lumbar support portion 121, and are plate-shaped when viewed from above. When the user's lumbar spine abuts against the lumbar support portion 121, the pair of connection portions 122 bend backward, and the pair of side portions 123 move toward each other and approach the two sides of the user's waist. The user's back and lumbar spine can be supported at the lumbar support portion 121, and at the same time, the left and right sides of the user's waist can be supported at the pair of side portions 123. The user's back and the left and right sides of the waist can be reliably supported to improve the user's posture.

[0167] The pair of side parts 123 may respectively include an inner side surface 123b facing the user, and an ilium support part 124c protruding from the inner side surface 123b and supporting the ilium of the user. In this case, the ilium of the user contacts each of the pair of ilium support parts 124c, and the left and right iliums of the user are supported by each ilium support part 124c. By supporting each ilium of the user, the waist of the user can be supported more reliably.

[0168] The lumbar vertebra support part 121 may include a protrusion 121b protruding toward the back of the user, and a first recess 121c recessed from the protrusion 121b and extending in the height direction of the user's body. In this case, the lumbar vertebra of the user can be gently supported by allowing the lumbar vertebra of the user to enter the first recess 121c. The user can visually recognize the first recess 121c of the lumbar vertebra support part 121 and grasp that the lumbar vertebra is supported by the lumbar vertebra support part 121. The first recess 121c can be used as a mark of the lumbar vertebra support part 121.

[0169] The pair of side portions 123 may respectively include rib support portions 125 that protrude from the inner side surface 123b at a position between the lumbar support portion 121 and each of the pair of ilium support portions 124c and support the lower portion of the user's ribs. In this case, the lower portion of the user's ribs can be supported by the pair of rib support portions 125 located between the lumbar support portion 121 and each of the pair of ilium support portions 124c.

[0170] In the lumbar support member 120, the pair of side portions 123 respectively include an inner side surface 123b facing the user, an ilium support portion 124c protruding from the inner side surface 123b and supporting the ilium of the user, and a second recessed portion 124b recessed from the ilium support portion 124c. By allowing the ilium of the user to enter the second recessed portion 124b, the ilium of the user can be gently supported. The user can visually recognize the second recessed portion 124b of the ilium support portion 124c and understand that the ilium is supported by the ilium support portion 124c. The second recessed portion 124b can be used as a mark of the ilium support portion 124c.

[0171] like Fig.10 , Fig.11 and Fig.12 As shown in the figure, the seat cushion 101 includes a lumbar support 120 and a seat portion 110 located below the lumbar support 120 and having a seat portion 111 on which a user sits. The seat cushion 101 includes the lumbar support 120. Therefore, the same effect as the above-mentioned lumbar support 120 can be obtained. The seat cushion 101 includes the seat portion 110 located below the lumbar support 120 and having the seat portion 111. Since the back and waist of the user sitting on the seat portion 111 can be reliably supported, the user's posture can be more reliably maintained in a good state.

[0172] For example, the posture detection system and posture detection method of the present invention can be applied to any of the seat cushion 110 and the waist support 120. That is, the posture detection system and posture detection method of the present invention can detect the posture of a user sitting on the seat cushion 110 and a user wearing the waist support 120, as in the seat cushions 100 and 200 described above. It should be noted that the shape, size, number, material, and arrangement of each part of the seat cushion and the waist support are not limited to the above examples, and can be appropriately changed.

[0173] In the above, the lumbar support 120 is described as having the side portion 123 having the ilium-opposing portion 124 and the rib supporting portion 125. However, a lumbar support 120 having a side portion that does not have at least one of the ilium-opposing portion 124 and the rib supporting portion 125 may be used. In the above, the lumbar support 120 is described as having an M-shape when viewed from above. However, a lumbar support 120 that does not have an M-shape when viewed from above may be used, and the shape of the lumbar support may be appropriately changed. For example, a lumbar support 120 that does not have at least one of the first recess 121c and the second recess 124b may be used.

[0174] For example, in the above embodiment, the seat cushion 101 is described as including the seat cushion portion 110 and the lumbar support member 120 that is attachable to and detachable from the seat cushion portion 110. However, the seat cushion may be a seat cushion in which the seat cushion portion 110 and the lumbar support member 120 are integrated. The seat cushion may be a seat cushion in which the seat cushion portion 110 and the lumbar support member 120 are integrally molded.

[0175] In the above description, the cushion portion 110 includes the seat portion 111 and the lumbar support portion 112, and the seat portion 111 includes the buttocks support portion 113 and the thigh support portion 114. However, the structure of the cushion portion connected to the lumbar support member according to the present invention can be appropriately changed within the scope of the above points. Explanation of symbols

[0176] 1...core material, 1b...lower surface, 2...seat part, 2b...ventilation hole, 3...lumbar support part, 4...buttocks support part, 4b...upper surface, 5...thigh support part, 5b...recessed part, 6...sciatica support part, 6b...recessed part, 6c...through hole, 6f...conical surface, 7...inclined surface, 8, 9...convex part, 9c...inclined part, 10...general part, 11...sacrum support part, 11d...protruding surface, 11f...recessed part, 11g...bottom surface, 11h...inner side surface, 20...fabric (inner fabric) 1 ... material), 22 ... outer fabric, 30 ... posture detection system, 31 ... seat sensor, 32 ... sacrum support sensor, 33 ... thigh support sensor, 34 ... cable, 35 ... communication unit, 40 ... control unit, 41 ... sitting determination unit, 42 ... posture determination unit, 43 ... leg crossing determination unit, 50 ... output unit, 51 ... display unit, 51b ... sitting time, 51c, 51d, 51f, 51g, 51h ... time, 51j ... time graph, 51k ... comment, 51p ... comment level, 52... alarm unit, 60... posture detection system, 70... fabric, 100, 200... cushion, 101... cushion, 110... cushion unit, 111... seat unit, 111b... vent, 112... lumbar support unit, 113... buttocks support unit, 114... thigh support unit, 115... ischium support unit, 116, 117... convex unit, 119... sacrum support unit, 119b... protruding surface, 119c... concave unit, 120... lumbar support member, 121... lumbar support unit, 12 1b...protrusion, 121c...first recess, 122...connecting portion, 123...side portion, 123b...inner side surface, 124...ilium opposite portion, 124b...second recess, 124c...ilium supporting portion, 125...rib supporting portion, 126...top portion, A1, D1...first direction D1, A2, D2...second direction, A3, D3...third direction, L1, L2...extension line, P...intersection portion, S...loading surface, T...information terminal, θ1...intersection angle, θ2...inclination angle.

Claims

1. A posture detection system for detecting the posture of a user sitting on a seat cushion, the seat cushion comprising a seat portion and a lumbar support portion, the seat portion comprising a buttocks support portion for supporting the buttocks of the user, the lumbar support portion comprising a sacrum support portion for supporting the sacrum of the user from behind, the posture detection system comprising: a seat sensor, the seat sensor being mounted on the seat and detecting whether the user is sitting on the seat; a sacrum support sensor which is mounted on the sacrum support and detects a posture of the user sitting on the seat; a posture determination unit configured to determine the posture of the user based on a result measured by the sacrum support sensor; as well as An alarm unit is configured to output an alarm when the posture determination unit determines that the posture of the user is bad.

2. The posture detection system according to claim 1, wherein: The sacrum support sensor detects whether the user's sacrum is in contact with the sacrum support sensor. The posture determination unit determines that the user's posture is hunched when the user's sacrum is not in contact with the sacrum support sensor.

3. The posture detection system according to claim 1 or 2, wherein: The sacrum support sensor measures a load of the user's sacrum on the sacrum support sensor, The posture determination unit determines that the user's posture is leaning too far backward when the load measured by the sacrum support sensor is equal to or greater than a certain value.

4. The posture detection system according to claim 1 or 2, wherein: The seat portion has a pair of thigh support portions arranged in a left-right direction when viewed from the user sitting on the seat portion. A pair of thigh support sensors are further provided, which are attached to each of the pair of thigh support sensors and measure the load on the thighs of the user sitting on the seat.

5. The posture detection system according to claim 1 or 2, wherein: A fabric is provided on which the seat portion sensor and the sacrum support portion sensor are mounted and which covers at least a portion of a core material of the seat cushion.

6. The posture detection system according to claim 5, wherein: An outer fabric covering the core material is provided, The fabric is an inner fabric covered by the outer fabric.

7. The posture detection system according to claim 4, wherein: The core material of the seat cushion has a recessed portion formed on the upper surface of the seat portion and a recessed portion formed on the upper surface of the thigh support portion. The seat sensor is embedded in a recessed portion of the seat, and the thigh support sensor is embedded in a recessed portion of the thigh support.

8. The posture detection system according to claim 1 or 2, wherein: The sacrum support portion has a protruding surface in a curved shape protruding forward, and a recessed portion recessed rearward from the protruding surface. The sacrum support sensor is mounted on the recessed portion of the sacrum support.

9. The posture detection system according to claim 4, wherein: A fabric covering at least a portion of the core material of the seat cushion, The fabric is an inner fabric on which the seat sensor, the sacrum support sensor, and the thigh support sensor are mounted.

10. The gesture detection system according to claim 5, wherein: The fabric covers only a portion of the core material, The fabric is fixed to the core material so as to cover the seat portion and the sacrum supporting portion.

11. The gesture detection system according to claim 4, wherein: The seat portion extends in a first direction and a second direction, the first direction being a front-rear direction when viewed from a user sitting on the seat portion, and the second direction being a left-right direction when viewed from a user sitting on the seat portion, The posture detection system has: Two seat sensors arranged along the second direction; 1 sacral support sensor; and Two thigh support sensors are arranged along the second direction.

12. The posture detection system according to claim 1 or 2, wherein: The buttocks support portion has a pair of ischium support portions that support ischium of the user sitting on the seat portion. The seat portion sensor is disposed around each of the pair of ischial support portions.

13. The posture detection system according to claim 1 or 2, wherein: A leg crossing determination unit is provided for determining whether the legs of the user sitting on the seat unit are crossed.

14. The gesture detection system according to claim 3, wherein: The posture determination unit determines that the posture of the user is appropriate when the load measured by the sacrum support sensor does not reach a certain value.

15. The gesture detection system of claim 4, wherein: The posture determination unit calculates a difference between loads on the thigh support sensors measured by a pair of thigh support sensors.

16. The gesture detection system of claim 4, wherein: The posture determination unit calculates the absolute value of the difference between the load on one thigh supporting part sensor received from the left thigh and the load on the other thigh supporting part sensor received from the right thigh, and when the calculated absolute value is greater than a certain value, it is determined that the left and right balance is poor and the posture is inappropriate, and when the calculated absolute value is not greater than the certain value, it is determined that the left and right balance is good.

17. The gesture detection system of claim 4, wherein: A leg-crossing determination unit is provided for determining whether the legs of the user sitting on the seat unit are crossed. The leg-crossing determination unit determines that the legs are crossed when one of the pair of thigh-support sensors receives a load from the thigh and the other thigh-support sensor receives no load from the thigh.

18. The posture detection system according to claim 1 or 2, wherein: comprising a sitting determination unit for determining whether the user is sitting on the seat unit, and a display unit for displaying the results of determination by the sitting determination unit and the posture determination unit, respectively. The display unit displays at least any one of the sitting time on the seat portion, the time of proper posture, the time of hunching over, the time of excessively leaning backward, the time of poor left and right balance, and the time of crossing legs in the form of a time graph.

19. The posture detection system according to claim 1 or 2, wherein: comprising a sitting determination unit for determining whether the user is sitting on the seat unit, and a display unit for displaying the results of determination by the sitting determination unit and the posture determination unit, respectively. The display unit displays a determination result of the sitting determination unit and a determination result of the posture determination unit in the form of comments.

20. A posture detection method for detecting the posture of a user sitting on a seat cushion, the seat cushion comprising a seat portion and a lumbar support portion, the seat portion having a buttocks support portion for supporting the buttocks of the user, the lumbar support portion having a sacrum support portion for supporting the sacrum of the user from behind, the posture detection method comprising: a step of detecting, by a seat sensor installed on the seat, whether the user is sitting on the seat; a step of detecting a posture of a user sitting on the seat portion by a sacrum support portion sensor mounted on the sacrum support portion; a step of determining the user's posture based on a result detected by the sacrum support sensor; as well as a step of outputting an alarm when it is determined in the step of determining that the posture of the user is bad.

Images