Seat back

Abstract

The invention provides a seat back, which can ensure the freedom degree of the frame shape of a seat frame and properly support a seat cushion. A seat frame (2) of a seat back (1), which supports a seat cushion (3) from a cushion back side, has a wire frame (2C) that supports a cushion lower portion (3A) of the seat cushion from the cushion back side. The seat cushion is provided with a cushion bent part (3B) which extends from the lower part of the cushion to the rear upper part of the seat in a manner of being rolled into the wire frame from the lower side of the seat. The wire frame has: a first wire (C1) extending in the seat width direction so as to support the lower part of the cushion from the seat rear side; and a second wire (C2) extending in the seat width direction so as to support the pad bend from the seat front side, which is the back side of the pad, at a position separated from the first wire toward the seat rear side. The seat cushion is provided with a first convex part (B1) which abuts against the first wire rod from the rear side of the seat on the cushion back surface of the cushion inverted bending part.

Description

Technical Field

[0001] The present invention relates to a seat back. More specifically, it relates to a seat back having a seat cushion and a seat frame that supports the seat cushion from the back side of the cushion. Background Art

[0002] In Patent Document 1, the following structure is disclosed: In a seat back, the seat cushion has a cushion bent portion that bends backward from the lower part of the cushion in a manner of winding the lower frame of the seat frame from below the seat. Thus, the lower part of the cushion and the cushion bent portion are supported by the lower frame from the back side of the cushion.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2013 - 107410 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] In the structure described in Patent Document 1, it is necessary to arrange the lower frame in a manner that can appropriately support the lower part of the cushion and the cushion bent portion, and the degree of freedom in the frame shape is likely to be impaired. Therefore, the present invention provides a seat back that can appropriately support the seat cushion while ensuring the degree of freedom in the frame shape of the seat frame.

[0008] Means for Solving the Problems

[0009] As a means for solving the above problems, the seat back of the present invention takes the following means.

[0010] That is, a first invention of the present invention is a seat back having a seat cushion and a seat frame that supports the seat cushion from the back side of the cushion. Among them, the seat frame has a wire frame that supports the lower part of the seat cushion from the back side of the cushion. The seat cushion has a cushion bent portion that extends from the lower part of the cushion to the upper rear side of the seat in a manner of winding the wire frame from below the seat. The wire frame has a first wire that extends in the seat width direction in a manner of supporting the lower part of the cushion from the rear side of the seat, and a second wire that extends in the seat width direction in a manner of supporting the cushion bent portion from the front side of the seat, which is the back side of the cushion, at a position away from the first wire toward the rear side of the seat. The seat cushion also has a first abutting portion that abuts against the first wire from the rear side of the seat on the back surface of the cushion at the cushion bent portion.

[0011] According to the first invention, the seat cushion can be assembled to the wire frame in such a manner that the lower part of the cushion and the bent-back part of the cushion are supported from the back side of the cushion by the first wire and the second wire. Moreover, the seat cushion can be assembled to the wire frame in such a manner that the first wire is sandwiched in the front-rear direction of the seat between the lower part of the cushion and the first abutting part. Therefore, even if the frame structure for supporting the lower part of the cushion and the bent-back part of the cushion is constituted by a simple wire structure including the first wire and the second wire, their support can be appropriately performed.

[0012] A second invention of the present invention is a seat backrest. In the above first invention, the bent-back part of the cushion is configured to be wound so as to abut against the first wire from the lower side of the seat, and the seat backrest further has a second abutting part that abuts against the second wire from the lower side of the seat.

[0013] According to the second invention, it is possible to make the bent-back part of the cushion difficult to dent with respect to the pressing force from below the seat.

[0014] A third invention of the present invention is a seat backrest. In the above second invention, the bent-back part of the cushion has a strip-shaped cushion groove part that is recessed from the back side of the cushion in the width direction of the seat between the first abutting part and the second abutting part.

[0015] According to the third invention, when the seat cushion is assembled to the seat frame, the part where the cushion thickness is thinned due to the cushion groove part is used as a hinge part, and the bent-back part of the cushion can be moved in a manner of opening or closing from the lower part of the cushion. Therefore, even if there is a bent-back part of the cushion, the seat cushion can be easily assembled to the seat frame.

[0016] A fourth invention of the present invention is a seat backrest. In any one of the above first to third inventions, the first abutting part is a protruding part that protrudes upward from the seat beyond the common outer tangent on the lower side of the seat that is tangent to the first wire and the second wire.

[0017] According to the fourth invention, the first abutting part can more appropriately abut against the first wire from the rear side of the seat. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a perspective view showing a schematic structure of a seat backrest according to a first embodiment.

[0019] Figure 2 is a rear view of the seat backrest.

[0020] Figure 3 is an exploded perspective view of the seat backrest.

[0021] Figure 4 is Figure 2 a cross-sectional view taken along line IV-IV of

[0022] Figure 5 This is a cross-sectional view corresponding to Figure 4 the state before the seat cushion is assembled to the seat frame. Detailed implementation mode

[0023] Hereinafter, the mode for implementing the present invention will be described with reference to the drawings.

[0024] <<First Embodiment>>

[0025] (Schematic structure of the seat backrest 1)

[0026] First, Figures 1 to 5 the structure of the seat backrest 1 of the first embodiment of the present invention will be described. In addition, in the following description, when indicating the front, rear, up, down, left, right and other directions, it refers to the respective directions shown in each figure.

[0027] In addition, when indicating in each direction such as the "seat width direction" by marking "seat", it refers to the respective directions based on the seat backrest 1. In addition, in the following description, when no specific reference figure is shown, or when there is no corresponding reference numeral in the reference figure, any one of Figures 1 to 5 the figures will be appropriately referred to.

[0028] As Figure 1 shown, the seat backrest 1 of the present embodiment is configured as the backrest of the last row seat of an automobile. The lower end portions on the left and right sides of the seat backrest 1 are connected to a pair of left and right pedestals 1A provided on the vehicle floor in such a manner that the backrest angle can be adjusted around the same axis extending in the seat width direction.

[0029] Specifically, the lower end portion on one side of the seat backrest 1 is connected to the pedestal 1A on the same side via an angle adjuster (not shown) in a rotatable and lockable manner. In addition, the lower end portion on the other side of the seat backrest 1 is rotatably connected to the pedestal 1A on the same side via a support shaft (not shown).

[0030] The angle adjuster (not shown) that connects one side of the seat backrest 1 to the pedestal 1A is always maintained in a state where the backrest angle of the seat backrest 1 is fixed. The fixed state of the backrest angle based on this angle adjuster is released by the operation of pulling up the lever 1B provided on the shoulder of the seat backrest 1 by the user.

[0031] By this release, the backrest angle of the seat backrest 1 can be adjusted. The seat backrest 1 can be rotated to a position where it tilts forward with respect to the seat by the above release. By this forward tilt, the luggage space (not shown) located behind the seat backrest 1 can be enlarged.

[0032] When the seat back 1 is tilted forward as described above, cargo placed in a luggage space (not shown) may abut against the lower portion of the seat that is tilted forward from behind the seat. However, even if cargo is placed on the seat back 1 as described above, the cushion structure of the lower portion is unlikely to sink into the seat.

[0033] The following describes in detail the specific structure of each part of the seat back 1. Figures 2 to 3 As shown in FIG. 1 , the seat back 1 has a metal seat frame 2 constituting its frame, a seat cushion 3 made of foamed polyurethane covering the front of the seat frame 2, and a seat cover 4 covering the seat cushion 3 from the cushion surface side. In addition, the seat back 1 has a resin backboard 5 covering its back side.

[0034] If Figure 3 As shown in the figure, the seat frame 2 has a pair of long plate-shaped side frames 2A extending in the seat height direction along the left and right side portions of the seat back 1. In addition, the seat frame 2 has an upper frame (not shown) extending in the seat width direction along the upper side portion of the seat back 1.

[0035] In addition, the seat frame 2 has a circular tubular reinforcement pipe 2B connected in a manner of being erected in the seat width direction between the middle parts of the left and right side frames 2A in the seat height direction. In addition, the seat frame 2 has a wire frame 2C bent into a U-shape in rear view and connected to the reinforcement pipe 2B in a manner of being suspended from the front side. In addition, the seat frame 2 has a hook wire 2D, and the hook wire 2D is connected between the two legs (vertical wire C3) of the U of the wire frame 2C in a manner of being erected in the seat width direction.

[0036] The wire frame 2C is formed by bending a wire member with a circular cross section. Specifically, the wire frame 2C has a pair of left and right longitudinal wires C3 extending in the seat height direction and a pair of left and right first wires C1 extending in a bent shape from the lower end of each longitudinal wire C3 to the outside in the seat width direction.

[0037] In addition, the wire frame 2C has a pair of left and right rear curved wires C4 extending in a curved shape from the extended front end of each first wire C1 toward the rear upper side of the seat. In addition, the wire frame 2C has a second wire C2 extending in a curved shape from the rear end of each rear curved wire C4 toward the inner side in the seat width direction in a manner connecting them.

[0038] If Figure 4 ​​​​​As shown, the second wire C2 is disposed at a position separated from each first wire C1 toward the upper rear of the seat when the seat backrest 1 is in an upright state at a reference angle. Each first wire C1 and the second wire C2 are in a relationship of extending parallel to each other in the seat width direction. Thus, each first wire C1 and the second wire C2 are in a disposition relationship in which a common outer tangent line L on the lower side of the seat that is tangent to each first wire C1 and the second wire C2 extends in an upper rear direction.

[0039] As Figure 3 shown, the seat cushion 3 covers the seat frame 2 in such a manner as to cover the entire front region of the seat frame 2. Further, the seat cushion 3 is pulled rearward of the seat in such a manner that its respective peripheral portions on the upper, lower, left, and right sides are rolled up from the outer peripheral side around the respective frame edges of the seat frame 2 assembled in a rear-view frame shape.

[0040] As Figure 4 shown, among them, the lower cushion portion 3A of the seat cushion 3 is provided so as to abut against each longitudinal wire C3 (refer to Figure 3 ) of the wire frame 2C and each first wire C1 from the front side of the seat. Further, a cushion bent-back portion 3B of the seat cushion 3 that extends rearward from the lower edge of the lower cushion portion 3A is pulled upward and rearward of the seat in such a manner as to roll up each first wire C1 and the second wire C2 of the wire frame 2C from the lower side of the seat.

[0041] As Figure 5 shown, the cushion bent-back portion 3B is formed in a shape that originally extends straight downward and rearward from the lower cushion portion 3A. On the upper surface shown in the drawing on the cushion back surface that becomes the cushion bent-back portion 3B, a first convex portion B1 and a second convex portion B2 that protrude in a form extending in the seat width direction are formed so as to be arranged separately from each other in the front-rear direction. Here, the first convex portion B1 corresponds to the "first abutting portion" of the present invention, and the second convex portion B2 corresponds to the "second abutting portion" of the present invention.

[0042] Further, on the cushion back surface of the cushion bent-back portion 3B, a cushion groove portion B3 that is recessed in a form extending in the seat width direction is formed between the first convex portion B1 and the second convex portion B2. The cushion bent-back portion 3B is set as follows to be rolled up from the lower side of the seat around the wire frame 2C.

[0043] That is, the cushion bent-back portion 3B is provided such that after an inner corner portion between it and the lower cushion portion 3A abuts against the first wire C1 from the front side of the seat, it is bent upward and rearward with the abutting point as a fulcrum. At this time, the cushion bent-back portion 3B uses a portion where the cushion thickness is thinned by the cushion groove portion B3 formed on its cushion back surface as a hinge portion, and easily bends upward a portion on the rear side of the seat relative to it.

[0044] As Figure 4As shown, through the above-mentioned reverse bending, the first protrusion B1 of the cushion reverse bending portion 3B detours to the rear side of the seat of the first wire C1, and presses the first wire C1 from the rear side of the seat. As a result, the seat cushion 3 is in a state where the first wire C1 is pressed and clamped between its cushion lower portion 3A and the first protrusion B1 in the front-to-back direction of the seat. In detail, the seat cushion 3 is in a state where the cushion back surface of its cushion reverse bending portion 3B abuts against the first wire C1 from the lower side of the seat and the first wire C1 is pressed and clamped by the cushion lower portion 3A and the first protrusion B1 in the front-to-back direction of the seat.

[0045] As a result, the seat pad 3 is held in a manner that is not misaligned with respect to the first wire C1 in the seat front-rear direction, and is assembled in a state in which it is positioned in the seat height direction. In addition, the pad inverted portion 3B is pressed together with the inverted portion so that the second convex portion B2 abuts against the second wire C2 from the lower side of the seat, and the pad back surface of its front end portion abuts against the second wire C2 from the rear side of the seat.

[0046] That is, the cushion bend 3B makes the back of the cushion and the inner corner of the second convex part B2 abut against the second wire C2 from the rear lower side of the seat. Through the above assembly, the cushion bend 3B is set relative to the first wire C1 and the second wire C2 so that they are rolled up from the lower side of the seat and sandwiched together in the front-rear direction of the seat.

[0047] In addition, the pad inverted portion 3B is set to abut against the first wire C1 and the second wire C2 from the lower side of the seat. In addition, the pad inverted portion 3B is set to clamp the first wire C1 in the front-rear direction of the seat.

[0048] As a result, the seat pad 3 is assembled in a state that is difficult to be displaced relative to the first wire C1 arranged at a position close to the backrest side of the wire frame 2C. In addition, the seat pad 3 is assembled in a state that is difficult to be displaced relative to the first wire C1 arranged at a position close to the backrest side of the wire frame 2C. Figure 1 When the seat is tilted forward as described above, even if luggage (not shown) abuts against the lower portion of the seat from behind, the cushion bend 3B of the cushion structure of the lower portion is unlikely to sink into the interior. The reason is that Figure 4 As shown in FIG. 1 , the first wire C1 and the second wire C2 are supported from the back side (lower side in the figure) of the pad by the amount corresponding to the pad inverted portion 3B.

[0049] The pad inverted portion 3B is assembled to the wire frame 2C as described above, and the first convex portion B1 and the second convex portion B2 are pulled closer to fill the gap between the first wire C1 and the second wire C2. The first convex portion B1 and the second convex portion B2 protrude above the seat in the form of a common tangent line L of the first wire C1 and the second wire C2.

[0050] ​​​​​The second convex portion B2 abuts the surface straight upward from the seat bottom against the second wire C2 from the lower side of the seat. Thus, when a load is pressed into the cushion bending portion 3B from the lower side of the seat, the second convex portion B2 is properly supported by the second wire C2 from the back side of the cushion (the upper side of the seat).

[0051] As Figure 3 shown, the seat cover 4 covers the seat cushion 3 from the front of the seat. The seat cover 4 is pulled backward into the seat in such a manner that the respective peripheral portions of the seat cover 4 in the up, down, left, and right directions are rolled into the respective peripheral portions of the seat cushion 3.

[0052] Moreover, the respective cover ends of the seat cover 4 pulled backward into the seat are hooked on the seat frame 2 and fixed. By this fixing, the seat cover 4 presses the seat cushion 3 against the seat frame 2 and holds it in a fixed position.

[0053] As Figure 4 shown, among them, the lower cover end of the seat cover 4 is pulled upward and backward into the seat in such a manner that the above-described cushion bending portion 3B is rolled into the seat from the lower side of the seat. Moreover, the hook 4A sewn to the front end of the lower cover end of the seat cover 4 is fixed by hooking on the hooking wire 2D joined to the wire frame 2C. By this fixing, the seat cover 4 holds the cushion bending portion 3B in a state of being properly pressed against the first wire C1 and the second wire C2.

[0054] The backrest 5 is assembled to the seat frame 2 from the back side of the seat using a clip, a hook, or other fixing members (not shown). Thus, the backrest 5 forms a rigid surface on the back of the seat back 1. By the above-described backrest 5, when the seat back 1 tilts forward as described above, a rigid surface that is difficult to flex even when a load is placed is formed on the back surface that faces upward. Figure 1 as

[0055] In summary, the seat back 1 of the present embodiment has the following structure. In addition, the reference numerals in parentheses below are the reference numerals corresponding to the respective structures shown in the above-described embodiment.

[0056] That is, the seat back (1) has a seat cushion (3) and a seat frame (2) that supports the seat cushion (3) from the back side of the cushion. The seat frame (2) has a wire frame (2C) that supports the lower portion of the cushion (3A) of the seat cushion (3) from the back side of the cushion. The seat cushion (3) has a cushion bending portion (3B) that extends upward and backward into the seat in such a manner that the wire frame (2C) is rolled into the seat from the lower side of the seat from the lower portion of the cushion (3A).

[0057] The wire frame (2C) has: a first wire (C1) extending in the seat width direction so as to support the lower part (3A) of the cushion from the rear side of the seat; and a second wire (C2) extending in the seat width direction so as to support the cushion reverse bending part (3B) from the front side of the seat which becomes the back side of the cushion at a position away from the first wire (C1) toward the rear side of the seat. The seat cushion (3) also has a first abutting part (B) that abuts against the first wire (C1) from the rear side of the seat on the cushion back surface of the cushion reverse bending part (3B).

[0058] According to the above structure, the seat cushion (3) can be assembled to the wire frame (2C) in such a way that the lower part (3A) of the cushion and the cushion reverse bending part (3B) are supported from the back side of the cushion by the first wire (C1) and the second wire (C2). Moreover, the seat cushion (3) can be assembled to the wire frame (2C) in such a way that the first wire (C1) is clamped in the front-rear direction of the seat between the lower part (3A) of the cushion and the first abutting part (B1). Therefore, even if the frame structure for supporting the lower part (3A) of the cushion and the cushion reverse bending part (3B) is composed of a simple wire structure including the first wire (C1) and the second wire (C2), their support can be appropriately carried out.

[0059] In addition, the cushion reverse bending part (3B) is configured to be rolled up so as to abut against the first wire (C1) from the lower side of the seat, and also has a second abutting part (B2) that abuts against the second wire (C2) from the lower side of the seat. According to the above structure, the cushion reverse bending part (3B) can be made difficult to dent with respect to the pressing force from below the seat.

[0060] In addition, the cushion reverse bending part (3B) has a strip-shaped cushion groove part (B3) that is recessed from the back side of the cushion in the seat width direction between the first abutting part (B1) and the second abutting part (B2). According to the above structure, when the seat cushion (3) is assembled to the seat frame (2), the part where the cushion thickness is thinned due to the cushion groove part (B3) is used as a hinge part, and the cushion reverse bending part (3B) can be moved in an open or closed manner from the lower part (3A) of the cushion. Therefore, even if there is a cushion reverse bending part (3B), the seat cushion (3) can be easily assembled to the seat frame (2).

[0061] In addition, the first abutting part (B1) becomes a protruding part that protrudes upward from the seat over the common outer tangent line (L) of the lower side of the seat that is tangent to the first wire (C1) and the second wire (C2). According to the above structure, the first abutting part (B1) can abut against the first wire (C1) more appropriately from the rear side of the seat.

[0062] Regarding other embodiments

[0063] As described above, an embodiment of the present invention has been described using one embodiment, but the present invention can be implemented in various ways in addition to the above-described embodiment.

[0064] 1. The seat back of the present invention can be applied not only to seats of vehicles such as automobiles and railways, but also to seats of transportation means other than vehicles such as airplanes and ships. In addition, the seat back can also be applied to seats other than transportation means.

[0065] 2. The wire frame may be composed of wire members in which one first wire and one second wire are connected to each other, or may be composed of different wire members. The second wire may also be structured to be disposed at the same height position as the first wire or at a position lower than the first wire.

[0066] When the second wire is located at a position higher than the first wire, the cushion bending portion of the seat cushion does not necessarily have to be structured such that the first contact portion protrudes as a protruding portion from the back surface of the cushion. That is, in the case of the above-described positional relationship, the cushion bending portion is formed in a shape in which the back surface of the cushion extends along a common outer tangent on the lower side of the seat that is tangent to the first wire and the second wire, and as a result, the back surface of the cushion becomes an inclined surface that rises backward. Therefore, by using this inclined surface as the first contact portion, a structure can be adopted in which the first wire is sandwiched in the front-rear direction of the seat between the first contact portion and the lower portion of the cushion.

[0067] 3. The second contact portion may contact the second wire at an inclined angle in addition to contacting the second wire straight from the lower side of the seat. The cushion bending portion does not necessarily have to contact the first wire from the lower side of the seat. This is because the seat cushion is assembled in such a manner that the first wire is sandwiched between the lower portion of the cushion and the first contact portion so as to appropriately maintain its position relative to the first wire.

[0068] 4. The initial shape of the cushion bending portion of the seat cushion may also be formed into a shape that bends in a manner of winding the wire frame from the lower side of the seat. Whether the initial shape of the cushion bending portion of the seat cushion is bent as described above or not, by forming a cushion groove portion, the cushion bending portion can be easily moved in a manner of opening or closing from the lower portion of the cushion. In addition, the seat cushion may also be structured such that there is no cushion groove portion in the cushion bending portion.

[0069] Description of Reference Numerals

[0070] 1 Seat back

[0071] 1A Base

[0072] 1B Rod

[0073] 2 Seat frame

[0074] 2A Side frame

[0075] 2B Reinforcing Tube

[0076] 2C Wire Frame

[0077] C1 First Wire

[0078] C2 Second Wire

[0079] C3 Vertical Wire

[0080] C4 Rear Curved Wire

[0081] 2D Hanging Wire

[0082] 3 Seat Cushion

[0083] 3A Lower Cushion

[0084] 3B Cushion Reverse Bend

[0085] B1 First Convex Portion (First Contact Portion)

[0086] B2 Second Convex Portion (Second Contact Portion)

[0087] B3 Pad Groove

[0088] 4 Seat Cover

[0089] 4A Hook

[0090] 5 Back Panel

[0091] L Common Outer Tangent

Claims

1. A seat back having a seat cushion and a seat frame supporting the seat cushion from a back side of the cushion, wherein: The seat frame has a wire frame supporting a cushion lower portion of the seat cushion from a cushion back side, The seat cushion has a cushion inverted portion extending from the cushion lower portion toward the upper rear of the seat in a manner of being rolled into the wire frame from the lower side of the seat, The wire frame has: a first wire extending in the seat width direction in a manner to support the lower portion of the pad from the rear side of the seat; and a second wire member extending in the seat width direction so as to support the cushion inverted portion from the front side of the seat, which becomes the back side of the cushion, at a position away from the first wire member toward the rear side of the seat, The seat pad further includes a first contact portion on a pad back surface of the pad inverted portion that contacts the first wire member from a rear side of a seat.

2. The seat back according to claim 1, wherein: The pad inverted portion is configured to be wound so as to abut against the first wire member from a lower side of a seat, and the seat back further includes a second abutting portion abutting against the second wire member from a lower side of a seat.

3. The seat back according to claim 2, wherein: The pad inverted portion includes a stripe-shaped pad groove portion recessed from a pad back side so as to extend in a seat width direction between the first abutting portion and the second abutting portion.

4. The seat back according to any one of claims 1 to 3, wherein: The first contact portion is a protruding portion that protrudes above the seat so as to cross a common external tangent line of the lower side of the seat that is tangent to the first wire and the second wire.

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