Seat device

Abstract

To provide a seat device capable of improving body pressure dispersibility.SOLUTION: A seat device 1 includes: a planar member 40 extended to a cushion frame 10 and having elasticity flexibly supporting the load of a seating person; and a deflection regulating member 20 fixed to the cushion frame 10 to regulate deflection to the seat rear side of the planar member 40 from the seat rear side. The deflection regulating member 20 includes: an inclined plane part 21 coming in contact to both side parts 42 in an area supporting the load of the seating person on the planar member 40 from the seat rear side by deflection of the planar member 40 to the seat rear side due to the load of the seating person; and an opening part 22 as a noncontact part not contact to a center part 41 in the area even when the planar member 40 deflects to the seat rear side and allowing the deflection of the center part 41.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to a seat device, and more particularly to a seat device including a stretchable planar member that is tensioned on a seat frame and elastically supports the weight of a seated occupant. [Background technology]

[0002] Patent Document 1 discloses a structure in which a planar member stretched over a seat frame elastically supports the weight of a seated occupant. The planar member is made of an elastic member such as a net material, and is configured to support the weight of the seated occupant by bending. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-123321 A Summary of the Invention [Problem to be solved by the invention]

[0004] If the planar member bends too much due to the weight of the seated occupant, the reaction force of the planar member tends to concentrate on areas where body pressure is high, such as under the buttocks, making the seating comfortable. Therefore, the present invention provides a seat device that can improve body pressure dispersion. [Means for solving the problem]

[0005] In order to solve the above problems, the seat device of the present invention takes the following measures.

[0006] That is, the seat device of the present invention has a planar member stretched on a seat frame and having elasticity for elastically supporting the load of a seated occupant, and a deflection restricting member fixed to the seat frame and restricting deflection of the planar member toward the back side of the seat by abutting against the back side of the seat. The deflection restricting member has contact portions that abut against both side portions of the planar member from the back side of the seat within an area where the planar member supports the load of the seated occupant as the planar member bends toward the back side of the seat due to the load of the seated occupant, and a non-contact portion that does not abut against a central portion of the above area and allows the central portion to deflect even if the planar member bends toward the back side of the seat.

[0007] According to the above configuration, the load of the seated occupant causes the planar member to bend toward the back of the seat, so that both side portions of the planar member come into contact with the contact portions of the deflection restricting member. This results in a state in which the load of the seated occupant is supported by the contact with the contact portions in addition to the tensile force of the planar member. As a result, the load of the seated occupant acting on the central portion of the planar member, where the deflection is not restricted, is reduced. This reduces the reaction force applied to the seated occupant from the central portion of the planar member. In addition, since the central portion of the planar member does not come into contact with the deflection restricting member even when the planar member is deflected, the load of the seated occupant can be elastically supported without bottoming out. As a result, the body pressure dispersion of the seat device can be improved.

[0008] The seat device of the present invention may further be configured as follows: the deflection restricting member is made of a rectangular frame-shaped body extending endlessly along the peripheral edge of the back side of the sheet of the planar member; the abutment portions are formed on vertical frame portions on both sides that constitute the frame-shaped body; and the non-abutment portions are made of openings within the frame of the frame-shaped body.

[0009] According to the above-mentioned configuration, the deflection restricting member can be made of an endless frame-shaped body with high structural strength. As a result, both side portions of the planar member can be properly supported from the rear side of the sheet by the abutment portion. Also, the non-abutment portion can be rationally formed by the opening in the frame-shaped body.

[0010] The seat device of the present invention may be further configured as follows: The horizontal frame portions connecting the vertical frame portions of the frame body do not come into contact with the planar member even if the planar member is bent toward the rear side of the seat.

[0011] According to the above-mentioned configuration, the weight of the seated occupant can be elastically supported so as to prevent bottoming out, thereby improving the body pressure dispersion of the seat device.

[0012] The seat device of the present invention may be further configured as follows: The contact portion comprises an inclined surface portion that inclines toward the rear side of the seat and extends inward in the seat width direction.

[0013] According to the above-mentioned configuration, the contact portions are oriented in a direction along the curved portions of both sides of the body of the seated occupant, and therefore the contact portions can more appropriately support both side portions of the planar member within the region that supports the weight of the seated occupant from the rear side of the seat.

[0014] The seat apparatus of the present invention may be further configured as follows: The planar member is applied to a seat cushion. Both side portions of the planar member where deflection is restricted are portions outside the ischial tuberosities of the AM50 dummy when the seated occupant is an AM50 dummy. The central portion of the planar member where deflection is permitted is a portion between the ischial tuberosities including directly below the ischial tuberosities of the AM50 dummy.

[0015] According to the above-mentioned configuration, of the area of ​​the planar member that supports the weight of a seated occupant, the areas on both sides that are outside the area directly below each ischial tuberosity where body pressure is high are supported from the rear side of the seat by the abutment parts. Therefore, the weight of the seated occupant can be elastically supported without bottoming out, and the body pressure dispersion of the seat device can be further improved.

[0016] The seat device of the present invention may be further configured as follows: The planar member is a seat surface member that directly contacts a seated occupant and supports the load.

[0017] According to the above configuration, the seat device can be configured as a net seat with excellent body pressure dispersion. [Brief description of the drawings]

[0018] [Figure 1] 1 is a perspective view illustrating a schematic configuration of a seat device according to a first embodiment. [Diagram 2] FIG. [Diagram 3] 1 is an exploded perspective view of a frame body with a planar member stretched thereover and a deflection restricting member, as viewed from the rear side of the seat. FIG. [Figure 4] 11 is a perspective view showing a state in which the deflection restricting member is assembled to the cushion frame. FIG. [Diagram 5] FIG. [Figure 6] 6 is a cross-sectional view taken along line VI-VI in FIG. 5. [Figure 7] 7 is a cross-sectional view taken along line VII-VII in FIG. 5. [Figure 8] 7 is a cross-sectional view corresponding to FIG. 6, illustrating a state in which the planar member is bent due to the load of a seated occupant. [Figure 9] 8 is a cross-sectional view corresponding to FIG. 7, illustrating a state in which the planar member is bent due to the load of a seated occupant. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0020] First Embodiment (Schematic configuration of seat device 1) First, a configuration of a seat device 1 according to a first embodiment of the present invention will be described with reference to Figures 1 to 9. In the following description, when directions such as front, back, up, down, left and right are indicated, they refer to the respective directions shown in each figure.

[0021] In addition, when a direction is indicated with "seat" added, such as "seat width direction," it refers to a direction based on the orientation of the seat device 1 described below. In the following description, when a specific reference figure is not shown or when there is no reference symbol corresponding to a reference figure, any of Figures 1 to 9 will be appropriately referenced.

[0022] As shown in Fig. 1, the seat device 1 according to this embodiment is configured as a seat to be installed in a bus vehicle such as a microbus. The seat device 1 includes a seat back 2 forming a backrest for a seated passenger and a seat cushion 3 forming a seating portion.

[0023] The seat back 2 and the seat cushion 3 are each connected to a support base 4 fixed to the floor. The support base 4 has a pair of left and right base frames 4F fixed to the floor. The lower ends of the left and right sides of the seat back 2 are integrally connected to the left and right base frames 4F of the support base 4, respectively.

[0024] 2, the rear end portions of the left and right sides of the seat cushion 3 are respectively connected to the left and right base frames 4F of the support base 4 so as to be rotatable about axes (not shown) extending in the seat width direction. As a result, the seat cushion 3 is configured to be switchable between a laid-down position (solid line position) in which the seat cushion 3 is laid down on the floor and can be used as a seating portion, and a raised position (imaginary line position) in which the seat cushion 3 is flipped up from the floor to the rear of the seat and overlapped in front of the seat back 2, as shown in FIG.

[0025] 2, the seat cushion 3 has a configuration in which a spiral spring SP is hooked between the rear end portions of both the left and right sides of the seat cushion 3 and each base frame 4F of the support base 4. As a result, the seat cushion 3 is kept in a state in which it is bounced up to a bounced-up position (position indicated by an imaginary line) by the spring force when the seat device 1 is not being used by a seated person, as shown in FIG.

[0026] Moreover, the seat cushion 3 can be switched to a reclined position (solid line position) where it can be used for sitting by the user tilting the seat cushion 3 forward against the spring force. Therefore, the user can use the seat cushion 3 as a seat by sitting down on the upper part of the seat cushion 3 that has been tilted forward. When the user lifts his / her hips off the seat cushion 3, the seat cushion 3 is again flipped up toward the rear of the seat by the spring force and switched to the flipped up position (imaginary line position).

[0027] The seat cushion 3 has a so-called net seat configuration in which the support structure for supporting the weight of the seated occupant is constituted by a planar member 40 made of a net material. This makes the seat cushion 3 thinner and lighter than a support structure made of a combination of urethane pads and metal springs. The configuration also contributes to carbon neutrality and reduces environmental impact.

[0028] The seat cushion 3 is configured to exhibit good body pressure dispersion even though the support structure is configured with the planar member 40 made of a net material, by suppressing concentration of reaction force caused by excessive bending of the planar member 40. The specific configuration of each part of the seat cushion 3 will be described in detail below.

[0029] (Configuration of each part of the seat cushion 3) 2, the seat cushion 3 has a metal cushion frame 10 that forms the framework of the seat cushion 3, and a resin deflection restricting member 20 that is attached to the upper part of the cushion frame 10 so as to cover the cushion frame 10. Here, the cushion frame 10 corresponds to the "seat frame" of the present invention.

[0030] The seat cushion 3 also has a resin frame 30 attached to the upper part of the deflection restricting member 20, and a planar member 40 made of a net material stretched within the frame of the frame 30. The seat cushion 3 also has a resin back cover 50 attached to the lower part of the cushion frame 10 so as to cover it.

[0031] The cushion frame 10 is assembled into a frame shape in plan view that extends along the peripheral side surfaces of the seat cushion 3. Specifically, the cushion frame 10 has a frame pipe 11 made of a round pipe material bent into a frame shape in plan view, and a pair of left and right elongated plate-shaped side frames 12 that are joined to the left and right frame side portions of the frame pipe 11 and extend rearward of the seat.

[0032] The cushion frame 10 is configured such that the rear end of each side frame 12 is rotatably connected via an unillustrated shaft to the corresponding base frame 4F of the support base 4. When the cushion frame 10 is tilted to a lying position around the unillustrated shaft relative to each base frame 4F, each side frame 12 abuts against the corresponding base frame 4F in the rotational direction and is stopped from rotating.

[0033] The deflection restricting member 20 is formed by blow molding of polypropylene resin into a hollow frame shape in plan view. As a result, the deflection restricting member 20 is configured to include a pair of left and right vertical frame portions 20A extending in the seat front-rear direction, and a pair of front and rear horizontal frame portions 20B extending in the seat width direction so as to connect the front and rear portions of the vertical frame portions 20A, respectively.

[0034] The deflection restricting member 20 is pressed into the cushion frame 10 from above the seat and integrally fitted thereto. Specifically, as shown in Fig. 3, the deflection restricting member 20 has a groove-shaped fitting recess 25 formed in the bottom surface thereof along the shape of the frame pipe 11 (see Fig. 2) of the cushion frame 10. The deflection restricting member 20 is integrally fitted into the frame pipe 11 by pressing the fitting recess 25 into the frame pipe 11 of the cushion frame 10 shown in Fig. 2 from above the seat in a fitted manner (see Fig. 4).

[0035] 2, the deflection restricting member 20 is configured such that inclined surface portions 21, which are inclined inward in the sheet width direction in a concave curved shape, are formed on the top plates of the left and right vertical frame portions 20A. As shown in FIGS. 5 and 6, each inclined surface portion 21 is located directly below a planar member 40 that is stretched over the upper portion of the deflection restricting member 20. Each inclined surface portion 21 is shaped to extend from the top plates of the left and right vertical frame portions 20A to an inner peripheral position facing the opening 22 within the frame of the deflection restricting member 20.

[0036] As shown in Fig. 6, each inclined surface portion 21 is configured to have a gap in the height direction between it and the planar member 40 before the weight of the seated occupant is applied to the seat cushion 3. As shown in Fig. 8, each inclined surface portion 21 comes into contact with the planar member 40 as the weight of the seated occupant is applied to the seat cushion 3 and the planar member 40 is deflected toward the rear side (lower side) of the seat.

[0037] Specifically, each inclined surface portion 21 abuts against both side portions 42 in the area of ​​the planar member 40 that supports the weight of the seated occupant, more specifically, against the portions that support the curved areas on both sides of the buttocks and thighs of the seated occupant, from the rear side of the seat. As a result, each inclined surface portion 21 restricts the progression of bending of both side portions 42 of the planar member 40 toward the rear side of the seat.

[0038] Here, each inclined surface portion 21 corresponds to a "contact portion" of the present invention. The seated occupant shown in this embodiment is an AM50 dummy (a dummy with a body type that corresponds to 50% of American men).

[0039] Each inclined surface portion 21 is shaped to curve in a concave curved surface shape along the curved parts on both sides of the buttocks and thighs of the seated occupant that contact it via the planar member 40. As a result, each inclined surface portion 21 supports the curved parts on both sides of the buttocks and thighs of the seated occupant by widely dispersing body pressure in a planar shape from the rear side of the seat.

[0040] Each inclined surface portion 21 is provided in an area outside the ischial tuberosities P when the seated occupant is an AM50 dummy. As a result, each inclined surface portion 21 is configured to support both side portions 42, which are areas outside the area directly below the ischial tuberosities P where body pressure is high, from the back side of the seat, within the area of ​​the planar member 40 that supports the weight of the seated occupant.

[0041] Each inclined surface portion 21 has a closed cross-sectional shape with high structural strength, which is hollow inside due to the deflection regulating member 20 being injection molded from polypropylene resin. As a result, each inclined surface portion 21 is configured to be able to firmly support both side portions 42 of the planar member 40 from the rear side of the seat. Here, each inclined surface portion 21 corresponds to the "contact portion" of the present invention.

[0042] 2, an opening 22 having a generally rectangular hole shape penetrating in the height direction is formed within the frame of the deflection restricting member 20. The opening 22 is located directly below a central portion 41 of a planar member 40 that is stretched over the upper portion of the deflection restricting member 20, as shown in FIGS.

[0043] 8, the opening 22 functions as a tolerance portion that allows the central portion 41 to flex when the weight of the seated occupant is applied to the seat cushion 3 and the planar member 40 flexes toward the back side (lower side) of the seat. Specifically, the opening 22 allows the central portion 41 between the ischial tuberosities P, including the area directly below each ischial tuberosity P where body pressure is high, to flex toward the back side of the seat, within the region of the planar member 40 that supports the weight of the seated occupant.

[0044] The opening 22 makes it difficult for the central portion 41 of the planar member 40 to bottom out when it is deflected toward the rear side of the seat due to the load of the seated occupant. The opening 22 corresponds to the "non-contact portion" of the present invention.

[0045] 2, a front inclined surface portion 23 that slopes straight toward the rear of the seat is formed on the top plate of the front horizontal frame portion 20B of the deflection restricting member 20. Also, a rear inclined surface portion 24 that slopes straight toward the front of the seat is formed on the top plate of the rear horizontal frame portion 20B of the deflection restricting member 20.

[0046] 5 and 7, the front inclined surface portion 23 and the rear inclined surface portion 24 are located directly below the planar member 40 that is tensioned on the upper part of the deflection restricting member 20. The front inclined surface portion 23 and the rear inclined surface portion 24 are shaped to extend from the top plate of each horizontal frame portion 20B to an inner peripheral edge position facing the opening 22 within the frame of the deflection restricting member 20.

[0047] As shown in Fig. 7, the front inclined surface portion 23 and the rear inclined surface portion 24 are configured to have a heightwise gap between them and the planar member 40 before the weight of the seated occupant is applied to the seat cushion 3. Also, as shown in Fig. 9, even when the weight of the seated occupant is applied to the seat cushion 3 and the planar member 40 is bent toward the back side (lower side) of the seat, the front inclined surface portion 23 and the rear inclined surface portion 24 do not come into contact with the planar member 40 and maintain a heightwise gap between them.

[0048] 2, the frame body 30 is formed into a frame shape in a plan view by injection molding of polypropylene resin. During the injection molding, the frame body 30 is formed such that the planar member 40 is set in a mold and molded integrally, so that the planar member 40 is integrally stretched within the frame.

[0049] As shown in Fig. 3, a plurality of resin clips CL are integrally attached to the bottom surface of each of the left and right frame sides and the bottom surface of the rear frame of the frame body 30. As shown in Fig. 2, the frame body 30 is assembled to the upper part of the deflection restriction member 20 in such a way that the outer peripheries of the clips CL are integrally overlapped with each other by inserting each clip CL from above the seat into each of the recessed seating surfaces 26 formed on the corresponding peripheral portions of the top plate of the deflection restriction member 20 and fastening them (see Fig. 4).

[0050] 2, the frame body 30 has a cover portion 31 extending in a planar shape from the rear portion of the frame toward the rear of the seat. The cover portion 31 extends rearward of the seat beyond the rear horizontal frame portion 20B of the deflection restricting member 20 and is configured to be placed directly under the seat back 2 (see FIG. 1).

[0051] The planar member 40 is formed of a mesh formed by weaving warp and weft threads made of PET resin into a planar shape. The planar member 40 is set in a mold during injection molding of the frame 30 and molded as a single unit, so that the planar member 40 is integrally stretched within the frame of the frame 30.

[0052] The planar member 40 has warp threads arranged in the front-rear direction of the seat made of multifilament and relatively low extensibility, while the planar member 40 has weft threads arranged in the width direction of the seat made of monofilament and relatively high extensibility. The planar member 40 is configured to exert an elastic supporting force that elastically supports the weight of a seated occupant by means of the weft threads.

[0053] The planar member 40 is configured such that the rear region supporting the buttocks of a seated occupant is more flexible than the front region supporting the thighs by adjusting the tension of the weft threads. As a result, the area of ​​the planar member 40 that supports the buttocks, which are subjected to relatively high body pressure, among the areas that support the weight of the seated occupant, is able to elastically support the buttocks in a manner that allows them to sink deeply.

[0054] Furthermore, among the regions of the planar member 40 that support the load of the seated occupant, the region that supports the thighs, which have a relatively low body pressure, is designed to elastically support the thighs with a harder support than the buttocks. In this way, the planar member 40 is designed to change its hardness according to the magnitude of the body pressure of the seated occupant, so that it is able to receive the load of the seated occupant by dispersing the body pressure widely. The type of planar member 40 is not particularly limited, and may be made of, for example, an elastic cloth material or a net material having a so-called three-dimensional knit structure.

[0055] 2, the back cover 50 is formed by injection molding of polypropylene resin into a frame shape in a plan view that fits the frame shape of the deflection restricting member 20. The back cover 50 is set on the cushion frame 10 so as to cover the seat from below, and is assembled integrally with the cushion frame 10. As described above in FIG. 1, the back cover 50 functions as a decorative cover that attractively covers the bottom surface of the seat cushion 3 that is exposed when the seat cushion 3 is flipped up toward the rear of the seat.

[0056] To sum up, the seat device 1 according to this embodiment has the following configuration: In the following, the reference characters in parentheses correspond to the respective components shown in the above embodiment.

[0057] That is, the seat device (1) has a planar member (40) tensioned on a seat frame (10) and having elasticity to elastically support the weight of a seated occupant, and a deflection restriction member (20) fixed to the seat frame (10) and restricting deflection of the planar member (40) toward the back side of the seat by abutting against the back side of the seat. The deflection restriction member (20) has contact portions (21) that abut against both side portions (42) within an area of ​​the planar member (40) that supports the load of the seated occupant as the planar member (40) deflects toward the back side of the seat due to the load of the seated occupant, from the back side of the seat, and a non-contact portion (22) that does not abut against a central portion (41) within the above-mentioned area and allows the central portion (41) to deflect even if the planar member (40) deflects toward the back side of the seat.

[0058] According to the above-mentioned configuration, the load of the seated occupant causes the planar member (40) to bend toward the rear of the seat, so that both side portions (42) of the planar member (40) come into contact with the abutment portions (21) of the deflection restricting member (20). This results in a state in which the load of the seated occupant is supported not only by the tensile force of the planar member (40) but also by the abutment with the abutment portions (21). As a result, the load of the seated occupant acting on the central portion (41) of the planar member (40), whose deflection is not restricted, is reduced. This reduces the reaction force applied to the seated occupant from the central portion (41) of the planar member (40).

[0059] In addition, since the central portion (41) of the planar member (40) does not come into contact with the deflection restricting member (20) even if the planar member (40) is deflected, the weight of the seated occupant can be elastically supported without bottoming out. As a result, the body pressure dispersion of the seat device (1) can be improved.

[0060] Moreover, the deflection restriction member (20) is made of a rectangular frame-shaped body that extends endlessly along the peripheral edge of the sheet rear side of the planar member (40). The abutment portions (21) are formed on the vertical frame portions (20A) on both sides that constitute the frame-shaped body. The non-abutment portions (22) are made of openings (22) within the frame of the frame-shaped body. With the above configuration, the deflection restriction member (20) can be made to have a high structural strength consisting of an endless frame-shaped body. As a result, the abutment portions (21) can appropriately support both side portions (42) of the planar member (40) from the sheet rear side. Furthermore, the non-abutment portions (22) can be rationally formed by the openings (22) within the frame of the frame-shaped body.

[0061] In addition, the horizontal frame portions (20B) connecting the vertical frame portions (20A) of the frame-shaped body do not come into contact with the planar member (40) even if the planar member (40) is bent toward the rear side of the seat. With the above-described configuration, the weight of the seated occupant can be elastically supported so as to prevent bottoming out. Therefore, the body pressure dispersion of the seat device (1) can be further improved.

[0062] In addition, the contact portion (21) is formed of an inclined surface portion (21) that is inclined inward in the seat width direction toward the back side of the seat. With the above configuration, the contact portion (21) is oriented in a direction that follows the curved parts on both sides of the body of the seated occupant. Therefore, the contact portion (21) can more appropriately support both side portions (42) of the planar member (40) within the area that supports the weight of the seated occupant from the back side of the seat.

[0063] Further, the planar member (40) is applied to the seat cushion (3). Both side portions (42) of the planar member (40) where the deflection is restricted are portions outside the ischial tuberosities (P) of the AM50 dummy when the seated occupant is an AM50 dummy. A central portion (41) of the planar member (40) where the deflection is permitted is a portion between the ischial tuberosities (P) of the AM50 dummy including directly below the ischial tuberosities (P).

[0064] According to the above-mentioned configuration, among the areas of the planar member (40) that support the weight of a seated occupant, the two side portions (42) that are areas on the outside of the areas directly below the ischial tuberosities (P) where body pressure is high are supported from the rear side of the seat by the abutment portions (21). Therefore, the weight of the seated occupant can be elastically supported without bottoming out, and the body pressure dispersion of the seat device (1) can be further improved.

[0065] In addition, the planar member (40) is a seat surface member that directly contacts the seated occupant and supports the load. According to the above configuration, the seat device (1) can be configured as a net seat with excellent body pressure dispersion properties.

[0066] Other embodiments Although one embodiment of the present invention has been described above, the present invention can be embodied in various forms as described below in addition to the above embodiment.

[0067] 1. The seat device of the present invention may be applied to vehicles other than automobiles, such as trains, and vehicles other than vehicles, such as aircraft and ships. The seat device can also be applied to spectator seats installed in various facilities, such as sports facilities, theaters, concert halls, and event venues, as well as non-vehicle seat devices such as massage seats.

[0068] 2. The planar member can be applied to the seat back as well as the seat cushion. When the planar member is applied to the seat back, in order to improve the dispersion of body pressure, support pipes for increasing the support rigidity may be provided between both side frames in the portions that support the lumbar and chest regions of the seated occupant, which are subject to high body pressure.

[0069] The planar member may be configured as a seat surface member in the seat cushion or seat back that directly contacts the seated occupant to support the load, or may be configured as a so-called cloth spring that is stretched across the seat frame and elastically supports the seat pad from the back side of the seat. Specific examples of the cloth spring structure include those disclosed in Japanese Patent Application Laid-Open No. 2014-240240 and Japanese Patent Application Laid-Open No. 2019-81506.

[0070] In addition, the planar member may be configured to be directly tensioned on the seat frame as disclosed in documents such as JP2018-197037A. The planar member may be configured to be tensioned with a uniform tension over the entirety.

[0071] 3. The contact portion of the deflection restricting member may be formed as a part of the frame constituting the deflection restricting member, or may be provided separately. The contact portion may be formed as a flat surface that faces straight toward the front surface of the sheet, or may be formed as an inclined surface that slopes inward in the sheet width direction toward the back side of the sheet. When the contact portion is formed as an inclined surface, the contact portion may be formed as a concave curved surface as shown in the above embodiment, or may be formed as a straight inclined surface.

[0072] 4. The non-contact portion of the deflection restricting member may be an opening in the frame that constitutes the deflection restricting member, or it may be a recess that is recessed relatively toward the back side of the sheet with respect to the contact portion.

[0073] 5. In the above embodiment, the side portions of the planar member whose deflection is restricted by the contact portions are the portions outside the ischial tuberosities of the AM50 dummy when the seated occupant is an AM50 dummy. However, the side portions of the planar member may be configured as portions outside the ischial tuberosities of another dummy such as an AM95 dummy. [Explanation of symbols]

[0074] 1 Seat device 2 Seat back 3 Seat cushion 4. Support Base 4F Base frame 10 Cushion frame (seat frame) 11 Frame pipe 12 Side frame 20 Deflection control member 20A Vertical frame 20B Horizontal frame part 21 Inclined surface part (contact part) 22 Opening (non-contact part) 23 Front inclined surface section 24 Rear inclined surface section 25 Fitting recess 26 Seat part 30 Frame 31 Cover 40 Planar members 41 Central part 42 Side part 50 Back cover SP spiral spring CL Clip P ischial tuberosity

Claims

1. A planar member that is stretched over the seat frame and elastically supports the load of a seated occupant; a deflection restricting member that is fixed to the seat frame and restricts deflection of the planar member toward a rear side of the seat by contacting the rear side of the seat, the deflection restriction member has abutment portions that abut against both side portions of the planar member within an area that supports the load of the seated occupant as the planar member deflects toward the seat back side due to the load of the seated occupant from the seat back side, and a non-contact portion that does not abut against a central portion within the area even when the planar member deflects toward the seat back side due to the load of the seated occupant and allows the central portion to deflect, The deflection control member is a rectangular frame-shaped body extending endlessly along the peripheral edge of the back side of the sheet of the planar member, the abutment portion is formed on the vertical frame portions on both sides that constitute the frame-shaped body, the non-abutment portion is an opening within the frame of the frame-shaped body, and the two horizontal frame portions connecting the two vertical frame portions of the frame-shaped body do not abut against the planar member even if the planar member bends toward the back side of the sheet.

2. 2. The seat device according to claim 1, The abutment portion is formed of an inclined surface portion that is inclined toward the rear side of the seat and inward in the seat width direction.

3. 3. The seat device according to claim 1 or 2, The planar member is applied to a seat cushion, and the two side portions where the deflection of the planar member is restricted are portions outside the ischial tuberosities of the AM50 dummy when the seated occupant is an AM50 dummy, and the central portion where the deflection of the planar member is permitted is the portion between the ischial tuberosities including directly below the ischial tuberosities of the AM50 dummy.

4. A seat device according to any one of claims 1 to 3, The seat apparatus wherein the planar member is a seat surface member that directly contacts a seated occupant and supports the load.

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