Vehicle seats

Abstract

To provide a vehicle seat that allows the seat cushion's rotation mechanism to operate smoothly when the seat back rotates to the rear of the seat cushion. [Solution] The vehicle seat has a rear side frame 11A connected to the seat back 2, a front side frame 11B located in front of the rear side frame, and a frame pivot shaft 15 connecting these side frames. When the seat back 2 rotates to the rear of the seat cushion 1, the rear side frame 11A and the front side frame 11B move so that they are aligned in the front-rear direction. The vehicle seat has a movement restricting part 60 that restricts the rear side frame when the rear side frame 11A and the front side frame 11B move, and a movement guide part 70 that guides the front side frame. At this time, the front side frame 11B moves so that its rear end rises.

Description

Technical Field

[0001] The present invention relates to a vehicle seat, and particularly to a vehicle seat including a seat cushion, a seat back, and a reclining device that rotates the seat back behind the seat cushion.

Background Art

[0002] Conventionally, a vehicle seat having a reclining mechanism for rotating a seat back behind a seat cushion is known. In addition, a seat in which a folding mechanism is provided in a cushion frame forming a skeleton of a seat cushion to improve the seating comfort of an occupant is known (see, for example, Patent Document 1). Specifically, a front portion and a rear portion of the cushion frame are divided and connected so as to be rotatable with respect to each other. Thereby, when the seat back is rotated behind the seat cushion, it is possible to suppress a displacement in the vertical direction of the occupant's back with respect to the seat back. That is, the occupant can smoothly shift from a normal posture to a reclined posture in which the occupant falls backward.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in a vehicle seat such as Patent Document 1, when the seat back rotates behind the seat cushion, it has been required that the rotation mechanism (folding mechanism) of the seat cushion operates more smoothly. For example, when the seat back rotates behind the seat cushion, it has been required that the front portion and the rear portion of the seat cushion can be guided so as to operate smoothly. Alternatively, when the seatback rotates to the rear of the seat cushion, causing the seat cushion and seatback to become flat (horizontally unfolded), it was required that the front and rear portions of the seat cushion be held in the appropriate positions.

[0005] The object of the present invention is to provide a vehicle seat that allows the rotation mechanism of the seat cushion to operate smoothly when the seat back rotates to the rear of the seat cushion. Another object of the present invention is to provide a vehicle seat that can hold the front and rear portions of the seat cushion in appropriate positions when the seat cushion and seat back are in a flat state. [Means for solving the problem]

[0006] The above problem is solved by the vehicle seat of the present invention, which comprises a seat cushion, a seat back, and a reclining device for rotating the seat back to the rear of the seat cushion, wherein the seat cushion comprises a cushion frame that forms the skeleton, the cushion frame has cushion side frames that are spaced apart in the seat width direction, the cushion side frame has a rear side frame connected to the seat back, a front side frame located in front of the rear side frame, and a frame pivot axis that rotatably connects the rear side frame and the front side frame to each other, and when the seat back rotates to the rear of the seat cushion, the seat back As the seat operates, the rear side frame and the front side frame move to align in the front-to-back direction of the seat. The vehicle seat further includes a movement restricting unit that restricts the movement of the rear side frame when the rear side frame and the front side frame move to align in the front-to-back direction of the seat, and a movement guide unit that guides the movement of the front side frame when the rear side frame and the front side frame move to align in the front-to-back direction of the seat. The front side frame is moved so that its rear end rises when the movement of the rear side frame is restricted by the movement restricting unit and the movement of the front side frame is guided by the movement guide unit.

[0007] With the above configuration, it is possible to realize a vehicle seat that allows the rotation mechanism (folding mechanism) of the seat cushion to operate smoothly when the seat back rotates to the rear of the seat cushion. More specifically, the vehicle seat comprises a rear side frame, a front side frame, and a frame pivot axis that constitute the folding mechanism. Furthermore, the vehicle seat includes a movement restricting section that restricts the movement of the rear side frame when the rear and front side frames move to align in the front-to-back direction of the seat, and a movement guide section that guides the movement of the front side frame. By providing the movement restricting section and the movement guide section, the folding mechanism of the seat cushion can be operated smoothly. Furthermore, with the above configuration, when the seat cushion and seat back move to a flat (horizontal) position, the rear end of the front side frame rises. In this way, the slight rise of the rear end of the front side frame allows the seat cushion and seat back to transition to a more horizontal position. The seat cushion and seat back can then be held in a nearly horizontal position. This allows the occupant to comfortably lean back.

[0008] In this case, the reclining device switches the seat back between a normal state in which an occupant can sit and a flat state in which the seat cushion is rotated from the normal state to the rear. When the seat back rotates to the flat state, the rear side frame and the front side frame move in conjunction with the movement of the seat back so as to be aligned in the front-rear direction of the seat. The movement restricting part restricts the movement of the rear side frame, and the movement guide part guides the movement of the front side frame, so that the rear end of the front side frame and the frame pivot axis rise. With the above configuration, when the seat cushion and seat back are in a flat position, the front portion (front side frame) and rear portion (rear side frame) of the seat cushion can be held in the appropriate position. In other words, the seat cushion can be properly supported when it is in a flat position.

[0009] In this case, the seat cushion and / or seat back is provided with a base member that supports it from below, and the moving guide portion has a guide projection provided at the rear end of the front side frame and a guide groove provided in the portion of the base member facing the rear end of the front side frame, into which the guide projection is guided, and the movement of the front side frame is guided by the guide projection entering the inside of the guide groove. As described above, by utilizing the guide protrusions and guide grooves, the front and rear portions of the seat cushion can be guided to move smoothly when the seat back rotates to the rear of the seat cushion. In addition, rattling during these movements can be suppressed.

[0010] In this case, the base member comprises a base frame that forms the skeleton, the base frame has base side frames that are spaced apart in the seat width direction, the guide projection protrudes laterally from the side surface of the rear end of the front side frame, the guide groove is formed in the part of the base side frame that faces the side surface of the rear end of the front side frame, the guide groove has a first groove that extends in the front-rear direction of the seat, and a second groove that is formed continuously from the rear end of the first groove and extends rearward while inclined upward, and the guide projection is preferably located in the first groove when the seat back is in a normal state and moves from the first groove to the second groove when the seat back rotates rearward. With the above configuration, when the seat cushion and seat back move to a flat position, the rear end of the front side frame rises slightly, and a guide groove is formed to correspond to this upward movement of the rear end of the front side frame. This allows the folding mechanism of the seat cushion to operate smoothly.

[0011] In this case, the guide groove is formed continuously from the rear end of the second groove and further has a third groove extending to the rear, the guide projection is located in the third groove when the seat back is in a flat state rotated to the rear of the seat cushion, and the moving guide portion guides the movement of the front side frame by the upper surface of the guide projection contacting the inner wall surface of the third groove. Furthermore, the third groove portion is preferably located at the rear end of the second groove portion and extends backward while being inclined downward. Furthermore, the reclining device is attached to the base side frame and includes a back rotation axis that rotates the seat back relative to the base side frame, and it is preferable that the second groove of the guide groove extends further back than the back rotation axis. The above configuration makes it possible to create a guide groove shape that corresponds to the movement trajectory of the seat cushion (front side frame, rear side frame). This allows the guide protrusions provided on the front side frame to move smoothly inside the guide groove. As a result, the folding mechanism of the seat cushion can be operated smoothly.

[0012] In this case, the guide groove should be positioned so as to overlap with the back pivot axis when viewed from above the seat. With the above configuration, each component can be compactly arranged in the front-to-back direction and the width direction of the seat.

[0013] In this case, the seat back is provided with a back frame that forms the skeleton, and the back frame has back side frames arranged at intervals in the seat width direction, and side connecting frames attached to the rear end of the back side frames and connecting the back side frames and the base side frames, and the guide groove is preferably positioned in the seat width direction between the side connecting frames of the seat back and the front side frames of the seat cushion. With the above configuration, each component can be arranged compactly in the width direction of the seat.

[0014] In this case, the base member is a height device for raising and lowering the seat cushion relative to the vehicle floor, the base side frame is a height side frame that is spaced apart in the seat width direction and supports the seat cushion from below, the height device further has a height link attached to the height side frame for raising and lowering the height side frame, and the guide groove is preferably formed in the portion of the height side frame that faces the side surface of the rear end of the front side frame. With the above configuration, a vehicle seat equipped with a reclining mechanism, a folding mechanism, and a height-adjustable mechanism can be realized. Furthermore, the movement of the seat cushion can be guided by the guide protrusions provided on the front side frame and the guide grooves provided on the height side frame.

[0015] In this case, the reclining device switches the seat back between a normal state in which an occupant can sit, a flat state in which the seat back is rotated backward from the normal state, and a folded state in which the seat back is folded toward the seat cushion. The height link is configured to tilt the seat cushion forward in conjunction with the movement of the seat back when the seat back rotates from the normal state to the folded state. With the above configuration, the seatback can be switched between "normal state," "flat state," and "folded state." In addition, the height link can be linked when the seatback rotates from the "normal state" to the "folded state."

[0016] At this time, a height cover that covers the height side frame from the outside in the sheet width direction is provided. The height cover is disposed between the height side frame and the front side frame in the sheet width direction. In a portion of the height cover that faces the guide groove, a second guide groove formed along the guide groove is provided. The moving guide portion preferably guides the movement of the front side frame by the guide convex portion entering into the guide groove and the second guide groove. With the above configuration, the height side frame can be covered by the height cover, and the appearance of the outer surface of the vehicle seat can be improved. In particular, even when the state of the vehicle seat is switched, it is possible to suppress the height side frame from being exposed.

Effect of the Invention

[0017] According to the present invention, when the seat back rotates rearward of the seat cushion, a vehicle seat capable of smoothly operating the rotation mechanism (mid-fold mechanism) of the seat cushion can be realized. Further, according to the present invention, when the seat cushion and the seat back move to a flat state (horizontal state), the rear end portion of the front side frame rises slightly, so that the seat cushion and the seat back can be transitioned to a state closer to horizontal. And the seat cushion and the seat back can be held in a state close to horizontal. Further, according to the present invention, by using the guide convex portion and the guide groove, the front portion and the rear portion of the seat cushion can be smoothly operated. Also, rattling of these operations can be suppressed. Further, according to the present invention, the shape of the guide groove corresponding to the movement locus of the seat cushion (front side frame, rear side frame) can be realized. Thereby, the guide convex portion provided on the front side frame can smoothly move inside the guide groove. Further, according to the present invention, each component can be arranged compactly in the seat front-rear direction and the seat width direction. According to the present invention, a vehicle seat including a reclining mechanism, a middle folding mechanism, and a height link mechanism can be realized. According to the present invention, the seat back can be switched between a "normal state", a "flat state", and a "folded state". According to the present invention, the high side frame can be covered with a height cover, and the appearance of the outer surface of the vehicle seat can be improved.

Brief Description of the Drawings

[0018] [Figure 1] It is a perspective view of the vehicle seat of the first embodiment. [Figure 2] It is a perspective view of the seat frame. [Figure 3] It is a side view of the seat frame in the "normal state". [Figure 4] It is a side view of the seat frame in the "flat state". [Figure 5] It is a side view of the seat frame in the "raised state". [Figure 6] It is a side view of the seat frame in the "folded state". [Figure 7] It is a perspective view of the cushion lock device. [Figure 8] It is an exploded perspective view of the cushion lock device. [Figure 9] It is a side view of the lock unit and the unlocking unit in the "locked state". [Figure 10] It is a side view of the lock unit and the unlocking unit in the "unlocked state". [Figure 11] It is a side view of the lock unit and the unlocking unit in the "reclining state". [Figure 12] It is an enlarged view of the main part of FIG. 2, and is a perspective view of the movement restricting portion and the movement guiding portion (guide convex portion, guide groove). [Figure 13] It is a perspective view of the movement restricting portion and the movement guiding portion (guide convex portion, guide groove) when viewed from the inside in the seat width direction. [Figure 14]This is a top view of the cushion side frame, height side frame, height cover, guide protrusion, and guide groove. [Figure 15] This is a side view of the height side frame, height cover, guide protrusion, and guide groove. [Figure 16] This is a side view of the movement restricting section and the movement guide section (guide protrusions and guide grooves) in the "normal state". [Figure 17] This is a side view of the movement restriction and movement guide sections when the device is in the "reclining position". [Figure 18] This is a side view of the movement restriction section and movement guide section when they are in the "flat state". [Figure 19] This is a side view of the movement restriction section and movement guide section when the unit is in the "folded state". [Figure 20] This is a perspective view of the seat frame of a vehicle seat according to the second embodiment. [Figure 21] This is a perspective view of the seat frame from a different angle. [Figure 22] This is a top view of the seat frame. [Figure 23] Figure 20 shows a cross-sectional view AA, which is a front cross-sectional view of the seat frame. [Figure 24] This is a side view of the movement guide section (guide protrusions, guide grooves) in the "normal state". [Figure 25] This is a side view of the movement guide section in the "flat state". [Modes for carrying out the invention]

[0019] Embodiments of the present invention will be described below with reference to Figures 1 to 25. This embodiment relates to a "vehicle seat" that enables the folding mechanism of the seat cushion to operate smoothly when the seat back rotates to the rear of the seat cushion. Furthermore, when it comes to vehicle seats, the side on which the occupant sits is the front side (front of the seat) relative to the seat back. Also, the side on which the occupant sits relative to the seat cushion is the upper side (upper side of the seat).

[0020] <Overview of the vehicle seat in the first embodiment> As shown in Figure 1, the vehicle seat S is a vehicle seat, specifically a front seat or middle seat positioned at the front of the vehicle. The vehicle seat S may also be a rear seat. The vehicle seat S is a seat that can be arranged between the "normal state" shown in Figures 1 to 3, the "flat state" shown in Figure 4, the "raised state" shown in Figure 5, and the "folded state" shown in Figure 6. Furthermore, the vehicle seat S can be switched from the "normal state" to a "reclining state" in which the seat back 2 is tilted at a predetermined angle relative to the vehicle floor (Figure 17).

[0021] The "normal state" is a state in which an occupant can sit, and the seat back 2 is upright relative to the seat cushion 1. The "flat state," also known as the fully flat state, is a state in which the seat cushion 1 and seat back 2 are extended horizontally (or nearly horizontally). In the "flat state," as shown in Figure 18, the rear end 11Be of the front portion (front side frame 11B) of the seat cushion 1 is slightly elevated. By raising the rear end of the front side frame 11B in this way, the seat cushion 1 and seat back 2 can be made to a more horizontal position. The "raised state" is a state in which the height positions of seat cushion 1 and seat back 2 are higher than the "normal state". The "folded state" is a state in which the entire vehicle seat S is folded by moving the seat cushion 1 and seat back 2 so as to collapse (sink) onto the vehicle floor.

[0022] Specifically, the occupant can move the entire seat forward and backward by operating the rail control lever 4d located on the front left side of the seat cushion 1. Furthermore, the occupant can change the height of the seat cushion 1 and seat back 2 by operating the height control lever 35 located on the front right side of the seat cushion 1. Furthermore, the occupant can rotate the seatback 2 forward or backward and recline it by operating the reclining lever 5d located on the shoulder portion of the seatback 2. These operations allow you to adjust the seat position of the vehicle seat S.

[0023] In the above configuration, the vehicle seat S further comprises a movement restricting unit 80 that restricts the movement of the rear portion (rear side frame 11A) of the seat cushion 1 when switching from the "normal state" to a "predetermined seat state," and a movement guide unit 90 that guides the movement of the front portion (front side frame 11B) of the seat cushion 1, as shown in Figures 12 and 13. By utilizing the movement restriction section 80 and the movement guide section 90, a vehicle seat S is made possible that allows for smooth seat arrangement. In particular, the folding mechanism of the seat cushion 1 can be operated smoothly. Furthermore, the seat cushion 1 can be held in the appropriate position when the vehicle seat S is in the "normal state," "recline state," or "flat state." Details will be described later. The following describes the details of each component of the vehicle seat S. Unless otherwise specified, the description assumes the "normal condition".

[0024] <Components of vehicle seats> As shown in Figures 1 and 2, the vehicle seat S comprises a seat body Sa having a seat cushion 1, a seat back 2, and a headrest 3; a rail device 4 that supports the seat body Sa so as to be movable forward and backward relative to the vehicle floor; and a reclining device 5 that rotatably connects the seat back 2 to the vehicle floor. Furthermore, the vehicle seat S includes a height device 30 that connects the seat body Sa to the vehicle floor (rail device 4) so ​​that it can be raised and lowered, and a cushion lock device 50 that connects the seat cushion 1 to the seat back 2 so that it can be rotated. Furthermore, as shown in Figures 3 to 5, the vehicle seat S is further equipped with a movement restricting unit 80 that restricts the movement of the rear portion (rear side frame 11A) of the seat cushion 1 when arranging the seat position of the seat body Sa, and a movement guide unit 90 that guides the movement of the front portion (front side frame 11B) of the seat cushion 1. The height adjustment device 30 corresponds to the "base member".

[0025] As shown in Figures 1 and 2, the seat cushion 1 is a seating portion that supports the occupant from below, and comprises a cushion frame 10 that forms the skeleton, a pad material 1a placed on the cushion frame 10, and a surface material 1b that covers the cushion frame 10 and the pad material 1a. The seat back 2 is a backrest that supports the occupant from behind, and comprises a back frame 20 that forms the skeleton, a pad material 2a, and a surface material 2b that covers the back frame 20 and the pad material 2a. The headrest 3 is a head section that supports the occupant's head from behind, and comprises left and right head pillars 3a that form the frame, a pad material 3b, and a surface material 3c that covers the head pillars 3a and the pad material 3b. The cushion frame 10, back frame 20, and head pillar 3a correspond to the "seat frame SF".

[0026] As shown in Figures 1 to 3, the rail device 4 is positioned vertically between the seat cushion 1 and the vehicle floor. The rail device 4 includes left and right lower rails 4a fixed to the vehicle floor and extending in the front-rear direction of the seat, left and right upper rails 4b slidably supported along the lower rails 4a, a locking member 4c that locks the upper rails 4b to the lower rails 4a so that they cannot slide, and a rail operating lever 4d that releases the locked state of the locking member 4c. The rail operating lever 4d is attached to the left front end of the seat cushion 1 and is connected to the locking member 4c by a cable. Height adjustment devices 30 (height brackets 36, 37) are attached to the upper surfaces of the left and right upper rails 4b.

[0027] As shown in Figures 1 to 3, the reclining device 5 includes a reclining body 5a that is driven when the seat back 2 is rotated, a back rotation axis 5b, a spiral spring 5c ​​that biases the seat back 2 to rotate forward around the back rotation axis 5b, and a reclining operation lever 5d that is operated to release the lock of the seat back 2. The reclining unit 5a can switch the state of the seat back 2 between a "locked state" in which it is fixed to the height device 30 (height side frame 41) and an "unlocked state" in which it can rotate relative to the height side frame 41. The back pivot shaft 5b is pivotally supported in the seat width direction by the height side frame 41 and the seat back 2 (side connecting frame 26). The spiral spring 5c ​​has one end locked to the height side frame 41 and the other end locked to the side connecting frame 26. The reclining control lever 5d is attached to the left shoulder area of ​​the seat back 2 and is connected to the reclining unit 5a by a cable.

[0028] The reclining device 5 can switch the seat body from the "normal state" shown in Figure 3 to the "reclining state" by rotating the seat back 2 backward relative to the vehicle floor (height device 30). Furthermore, the reclining device 5 can switch the seat body to the "flat state" shown in Figure 4 by rotating the seat back 2 further backward. The reclining device 5 can also switch the seat body from the "normal state" shown in Figure 3 to the "folded state" shown in Figure 6 by rotating the seat back 2 forward relative to the vehicle floor (height device 30).

[0029] <<Cushion Frame>> As shown in Figures 2 to 14, the cushion frame 10 consists of a rectangular frame-like body and includes cushion side frames 11 arranged on the left and right sides, a plate-shaped pan frame 12 installed on the front end portion of each cushion side frame 11, a connecting pipe 13 connecting the rear portions of each cushion side frame 11, and a plurality of pressure-receiving members 14 (pressure-receiving springs) that are attached to the pan frame 12 and the connecting pipe 13 and extend in a snake-like manner in the front-rear direction of the seat.

[0030] As shown in Figures 2 and 3, the cushion side frame 11 is a long, plate-shaped frame in the front-to-back direction of the seat. A reclining device 5 is attached to the rear part of the right cushion side frame 11, and height adjustment devices 30 are attached to the lower parts of the left and right cushion side frames 11.

[0031] As shown in Figures 2 to 14, the left and right cushion side frames 11 each have a folding mechanism. Specifically, the cushion side frame 11 includes a rear side frame 11A connected to the seat back 2 (side connecting frame 26), a front side frame 11B located in front of the rear side frame 11A, and a frame pivot shaft 15 that connects the rear side frame 11A and the front side frame 11B so that they can rotate relative to each other. The rear side frame 11A, the front side frame 11B, and the frame pivot axis 15 correspond to the "folding mechanism (folding device)".

[0032] The rear side frame 11A is a curved plate-shaped frame and is attached to the outer surface of the side connecting frame 26 of the seat back 2 and the outer surface of the rear end of the front side frame 11B. Specifically, the rear end of the rear side frame 11A is rotatably attached to the side connecting frame 26 via a cushion pivot shaft 51. Furthermore, the front end of the rear side frame 11A is rotatably attached to the front side frame 11B via the frame pivot shaft 15.

[0033] The rear side frame 11A includes a frame body 11Aa, a reinforcing flange 11Ab and a fitting flange 11Ac protruding from the upper end of the frame body 11Aa, and a reinforcing flange 11Ad protruding from the lower end of the frame body 11Aa. The fitting flange 11Ac fits into the fitting flange 11Bc formed on the upper end of the front side frame 11B. This allows the rear side frame 11A to be easily positioned.

[0034] As shown in Figures 7 and 8, a cushion lock device 50 is attached to the outer surface of the right rear side frame 11A. Additionally, resin outer covers 77 are attached to the outer surfaces of the left and right rear side frames 11A.

[0035] The front side frame 11B is a long, plate-shaped frame in the front-to-rear direction of the seat, and is attached to the front end of the rear side frame 11A and the lateral portion of the pan frame 12. Specifically, the rear end of the front side frame 11B is rotatably attached to the rear side frame 11A via a frame pivot shaft 15. Furthermore, the front ends of the left and right rear side frames 11A are connected by a pan frame 12, and the rear ends of the left and right rear side frames 11A are connected by a connecting pipe 13.

[0036] The front side frame 11B includes a frame body 11Ba, a reinforcing flange 11Bb and a fitting flange 11Bc that protrude inward from the upper end of the frame body 11Ba, and a reinforcing flange 11Bd that protrudes inward from the lower end of the frame body 11Ba. The fitting flange 11Bc fits into the fitting flange 11Ac formed on the upper end of the rear side frame 11A.

[0037] As shown in Figures 12 and 13, a movable guide portion 90 (guide projection 91) is provided on the inner surface of the front side frame 11B, in a portion slightly forward of the frame pivot axis 15 and slightly below the frame pivot axis 15. The guide projection 91 protrudes inward from the inner surface of the front side frame 11B, enters into the guide groove 95 formed at the upper end of the height side frame 41, and is supported by the guide groove 95.

[0038] In the above configuration, as shown in Figures 16 to 18, when the seat back 2 rotates to the rear of the seat cushion 1, the rear side frame 11A and the front side frame B move in conjunction with the movement of the seat back 2 so that they are aligned in the front-to-back direction of the seat. At this time, the movement of the rear side frame 11A is restricted by the movement restricting unit 80, and the movement of the front side frame 11B is guided by the movement guide unit 90, causing the rear end portion 11Be of the front side frame 11B to rise slightly. This allows the seat cushion 1 and seat back 2 to transition to a more horizontal position.

[0039] As shown in Figure 2, a lever mounting bracket 16 for holding the rail operating lever 4d is fixed to the left front end portion of the pan frame 12. The rail operating lever 4d is rotatably mounted to the lever mounting bracket 16. Furthermore, a lever mounting bracket 17 for holding the height adjustment lever 35 is fixed to the front right end portion of the pan frame 12. The height adjustment lever 35 is rotatably mounted to the lever mounting bracket 17.

[0040] <<Back frame>> As shown in Figures 2 to 6, the back frame 20 consists of a rectangular frame-like body and comprises back side frames 21 arranged on the left and right sides, an upper frame 22 connecting the upper ends of each back side frame 21, a lower frame 23 connecting the lower ends of each back side frame 21, a member frame 24 connecting each back side frame 21, and a board frame 25 attached to the rear surfaces of these frames 21, 22, 23, and 24. Furthermore, the back frame 20 is attached to the lower end of the back side frame 21 and includes a side connecting frame 26 that connects the back side frame 21 and the height side frame 41.

[0041] A pillar retaining member 27, which holds the head pillar 3a, is fixed to the central part of the upper frame 22 in the width direction. Furthermore, a lever mounting bracket 28 for holding the reclining operation lever 5d is fixed to the left side portion of the upper frame 22. The reclining operation lever 5d is rotatably mounted to the lever mounting bracket 28.

[0042] The side connecting frame 26 is a plate-shaped frame with a C-shaped cross-section, and is attached to the outer surface of the back side frame 21 and the inner surface of the height side frame 41. Specifically, the upper portion of the side connecting frame 26 is fixed in place so as to sandwich the back side frame 21. Furthermore, the lower portion of the side connecting frame 26 is rotatably attached to the height side frame 41 via a back pivot shaft 5b.

[0043] As shown in Figure 2, a reclining device 5 is attached to the outer surface of the right-side connecting frame 26. More specifically, a height side frame 41 is attached to the outer surface of the right side connecting frame 26, and a reclining device 5 is attached to the outer surface of the height side frame 41. The seat back 2 rotates around the back pivot axis 5b relative to the height side frame 41 when the reclining device 5 is operated.

[0044] As shown in Figure 12, a plate-shaped movement restricting portion 80 is fixed to the rear surface of the lower end of the side connecting frame 26, protruding outward in the width direction of the side connecting frame 26. The movement restricting section 80 is positioned to overlap with the rear side frame 11A when viewed from the front of the seat, and is positioned opposite the rear side frame 11A. The movement restricting unit 80 has the function of restricting the movement of the rear side frame 11A when the seat back 2 rotates to the rear.

[0045] <<Height device>> The height adjustment device 30, also known as the height link device, as shown in Figures 1 to 6, is a device that can adjust the height position of the seat body Sa, and is installed between the seat body Sa and the rail device 4. The height adjustment device 30 includes left and right first height links 31 arranged at intervals in the seat width direction, left and right second height links 32 arranged behind the first height links 31, and left and right third height links 33 arranged inward from the left and right first height links 31 and the second height links 32. Furthermore, the height adjustment device 30 includes a locking member 34 that locks the seat body Sa so that it cannot be raised or lowered, and a height adjustment lever 35 for releasing the lock state of the locking member 34. The height adjustment device 30 allows the height of the seat body Sa to be adjusted, with the second height link 32 acting as a drive link and the first height link 31 and third height link 33 acting as driven links.

[0046] As shown in Figure 2, the height adjustment device 30 further includes a height frame 40 that supports the seat cushion 1 and seat back 2 from below. The height frame 40 includes left and right height side frames 41, a front connecting frame 42 that connects the front portions of the left and right height side frames 41, a central connecting frame 43 that connects the central and rear portions of the left and right height side frames 41, and a rear connecting frame 44. Furthermore, the height device 30 is fixed to the upper surface of the rail device 4 (upper rail 4b) and includes a first height bracket 36 that connects the rail device 4 and the first height link 31, and a second height bracket 37 that connects the rail device 4 and the second height link 32.

[0047] The seat body Sa and height frame 40 are mounted to the rail device 4 so that they can be raised and lowered by the operation of the height links 31 and 32. The seat cushion 1 is mounted so as to be able to move up and down relative to the height frame 40 by the operation of the third height link 33. The seat back 2 is rotatably mounted to the height side frame 41, with respect to a back pivot axis 5b that is pivotally supported at the rear end of the height side frame 41.

[0048] Furthermore, the third height link 33 is a link that rotates the seat cushion 1 in conjunction with the rotational movement of the seat back 2. As shown in Figures 3 and 4, when the seat back 2 rotates backward around the back pivot axis 5b, the third height link 33 rotates backward around the link pivot axis 38. Furthermore, as shown in Figures 3 and 6, when the seat back 2 rotates forward around the back pivot axis 5b, the third height link 33 rotates forward around the link pivot axis 38. This allows the seat cushion 1 and seat back 2 to be switched from the "normal state" to the "flat state," and also from the "normal state" to the "folded state."

[0049] A movable guide section 90 (guide groove 95) is provided in the upper part of the rear end of the height side frame 41. The guide groove 95 is formed by cutting out the upper portion of the height side frame 41 from the front to the rear, and is a groove into which the guide projection 91 is inserted. The guide projection 91 is supported by the guide groove 95.

[0050] In the above configuration, as shown in Figures 3 and 6, the height links 31, 32, and 33 (especially the third height link 33) move to tilt the seat cushion forward in conjunction with the movement of the seat back 2 when the seat back 2 rotates from the "normal state" to the "folded state". This allows the height adjustment device 30 to be linked to the rotation of the seat body (seat back 2) from the "normal state" to the "folded state".

[0051] <<Cushion locking device>> As shown in Figures 2, 7 to 11, the cushion locking device 50 is a device that rotatably connects the seat cushion 1 to the seat back 2, and is attached to the right side portion of the seat body Sa. The cushion locking device 50 locks the rear side frame 11A and the front side frame 11B when in the "normal state" shown in Figure 9, and releases the lock on the rear side frame 11A and the front side frame 11B when switching from the "normal state" to the "reclining state" or the "flat state" shown in Figure 11.

[0052] As shown in Figures 7 and 8, the cushion locking device 50 includes a cushion pivot shaft 51, a locking unit 60 that locks the rotational movement of the side frames 11A and 11B, and a lock release unit 70 that releases the locked state of the locking unit 60. The locking unit 60 locks the rotational movement of the side frames 11A and 11B when they are in the "normal state" and "folded state" as shown in Figure 9. On the other hand, the unlocking unit 70 unlocks the side frames 11A and 11B when the chair is in the "reclining position" and the "flat position". When the locks on the side frames 11A and 11B are released, the front side frame 11B becomes rotatable around the frame pivot axis 15 relative to the rear side frame 11A.

[0053] As shown in Figures 7 and 8, the locking unit 60 includes a shaft fixing plate 61, an operating plate 62, and an elastic rubber 63. The locking unit 60 is located on the outside of the rear side frame 11A in the seat width direction.

[0054] The shaft fixing plate 61 is a circular member that is fixed to the frame pivot shaft 15. The shaft fixing plate 61 has an engagement groove 61a that can engage with the locking piece 62c of the operating plate 62. When the locking piece 62c engages with the engagement groove 61a, the rotation of the shaft fixing plate 61 is restricted, thereby locking the rear side frame 11A and the front side frame 11B via the frame pivot shaft 15.

[0055] The operating plate 62 is a plate member connected to the outer wall of the rear side frame 11A. The operating plate 62 has a plate base portion 62a, a plate rotation shaft 62b, a locking piece 62c, and a window hole 62d. The plate base portion 62a is rotatably connected to the rear side frame 11A via the plate rotation shaft 62b. As a result, the plate base portion 62a is displaced between a "locked position" in which the locking piece 62c is engaged with the engagement groove 61a of the shaft fixing plate 61, and an "unlocked position" in which the locking piece 62c is disengaged from the engagement groove 61a.

[0056] The elastic rubber 63 contacts the operating plate 62, biasing the operating plate 62 in a direction in which the locking piece 62c engages with the engagement groove 61a.

[0057] As shown in Figures 7 and 8, the unlocking unit 70 includes an operating arm 71, a release operating member 72, and a spring 75. The release operating member 72 includes a rotating plate 73 and a rotation transmission member 74. The operating arm 71 and the spring 75 are provided on the outer surface of the rear side frame 11A in the seat width direction. The release actuation member 72 is provided on the inner surface of the rear side frame 11A.

[0058] The operating arm 71 is a plate member having a bent shape and includes an arm base portion 71a, a bent portion 71b, an arm rotation axis 71c, an engaging piece 71d, a contact portion 71e, and a spring fixing portion 71f. The arm base portion 71a is rotatably connected to the rear side frame 11A via the arm rotation axis 71c. The arm base portion 71a transitions between a "normal position" in which the engaging piece 71d is separated from the operating plate 62 (engaged surface 62e) and an "unlocked position" in which the engaging piece 71d is in contact with the engaged surface 62e.

[0059] The engaging piece 71d is located inside the operating plate 62 (window hole 62d) and contacts the engaged surface 62e when in the "unlocked position". Specifically, the engaging piece 71d penetrates the rear side frame 11A and the inner cover 76 and contacts the engaged surface 62e. The contact portion 71e contacts the release operating piece 73c of the release operating member 72. One end of the spring 75 is fixed to the spring fixing part 71f.

[0060] As shown in Figure 8, the release operating member 72 is a member that rotates in conjunction with the rearward movement of the seat back 2. The release operating member 72 includes a rotating plate 73 and a rotation transmission member 74.

[0061] The rotating plate 73 has a circular portion 73a, an extended portion 73b extending radially from the circular portion 73a, and a release operating piece 73c provided at the tip of the extended portion 73b. An inner cover 76 is provided between the release operating member 72 and the rear side frame 11A.

[0062] The rotation transmission member 74 has a pair of fixed flanges 74a, a cylindrical portion 74b, and a contact portion 74c. The fixed flange 74a is secured to the rotating plate 73 by fastening bolts. The cylindrical portion 74b is rotatably supported with respect to the back pivot axis 5b. A contact portion 74c is formed on the outer circumference of the cylindrical portion 74b. The contact portion 74c comes into contact with the protruding portion 26b of the rotating bracket 26a provided on the side connecting frame 26 when the seat back 2 rotates to the rear of the seat cushion 1, and rotates together with the seat back 2.

[0063] The spring 75 biases the operating arm 71 (engaging piece 71d) in a direction that prevents it from releasing the lock. Specifically, one end of the spring 75 is connected to the spring fixing portion 71f of the operating arm 71, and the other end is connected to the rear side frame 11A. The spring 75 then biases the operating arm 71 (engaging piece 71d) in a direction that moves it away from the engaged surface 62e formed on the operating plate 62.

[0064] <<Operation of the locking and unlocking units>> Next, based on Figures 9 to 11, we will explain how the lock unit 60 and the unlock unit 70 operate when the vehicle seat S switches from the "normal state" to the "flat state".

[0065] In the "normal state" shown in Figure 9, the operating plate 62 (locking piece 62c) is engaged with the shaft fixing plate 61 (engagement groove 61a). Therefore, the rotation of the rear side frame 11A and the front side frame 11B is locked, and they are unable to rotate relative to each other via the frame pivot shaft 15. In the "normal state," the rotating bracket 26a (protruding portion 26b) of the side connecting frame 26 shown in Figure 8 is located away from the rotation transmission member 74 (contact portion 74c).

[0066] Then, when the seat back 2 rotates to the rear of the seat cushion 1, the rotating bracket 26a (protrusion 26b) shown in Figure 8 rotates together with the seat back 2. As the seat back 2 rotates further, the protrusion 26b shown in Figure 8 rotates along the outer circumference of the back rotation axis 5b and comes into contact with the rotation transmission member 74 (contact portion 74c). As the seat back 2 rotates further, the protrusion 26b presses against the rotation transmission member 74. As a result, as shown in Figure 10, the release operating member 72 rotates in the direction of arrow A3 around the back rotation axis 5b.

[0067] At this time, as shown in Figure 10, the release operating member 72 rotates around the arm rotation axis 71c in the direction of arrow A4 by the release operating piece 73c. As a result, the operating arm 71 (engaging piece 71d) comes into contact with the engaged surface 62e formed on the operating plate 62 (window hole 62d). As shown in Figure 10, the operating plate 62 rotates about the plate rotation axis 62b in the direction of arrow A5 by the engaging piece 71d. This causes the operating plate 62 (locking piece 62c) to detach from the shaft fixing plate 61 (engagement groove 61a), and the lock unit 60 is released.

[0068] Figure 11 shows the seat back 2 rotated to the rear of the seat cushion 1 in a "flat state" and the lock unit 60 released. As shown in Figure 11, the operating plate 62 (locking piece 62c) is detached from the shaft fixing plate 61 (engagement groove 61a). The operating plate 62 is also biased by the elastic rubber 63. Therefore, when the vehicle seat S returns from the "flat state" to the "normal state," the locking piece 62c engages with the engagement groove 61a again, and the rotation of the folding mechanism is locked.

[0069] Furthermore, if the seat back 2 rotates forward of the seat cushion 1, the lock unit 60 will not be released by the unlock unit 70 and will maintain its locked state.

[0070] With the above configuration, the vehicle seat S switches between "normal state," "recline state (flat state)," and "unlocked state." Furthermore, the locking unit 60 and the unlocking unit 70 can fold the seat cushion 1 in the middle when the seat back 2 is tilted backward, and can lock the folded position of the seat cushion 1 in the "normal state". This makes it possible to suppress the decrease in seating comfort of the vehicle seat S while the vehicle is in motion.

[0071] <<Movement Restriction Department, Movement Guidance Department>> As shown in Figures 12 and 13, the movement restricting section 80 is a member that restricts the movement of the rear portion (rear side frame 11A) of the seat cushion 1 when the seat body switches from the "normal state" to the "flat state". The movement restricting section 80 is a plate-shaped member that is attached to the rear surface of the lower end of the side connecting frame 26 and protrudes outward in the width direction of the side connecting frame 26. The movement restriction section 80 is positioned to overlap with the rear side frame 11A when viewed from the front of the seat, and faces the rear side frame 11A. The movement restricting unit 80 restricts the movement of the rear side frame 11A when the seat back 2 rotates to the rear.

[0072] The movement restricting section 80 may be attached to a part of the seat back 2 that is different from the side connecting frame. Alternatively, the movement restricting section 80 may be provided on the height side frame 41 (base side frame), or on a part of the height frame 40 that is different from the height side frame 41. The movement restriction section 80 may extend from the rail device 4 (upper rail 4b).

[0073] As shown in Figures 12 to 19, the movement guide section 90 is a member that guides the movement of the front portion (front side frame 11B) of the seat cushion 1 when the seat body switches from the "normal state" to the "flat state". The movable guide section 90 includes a guide projection 91 provided at the rear end of the front side frame 11B, and a guide groove 95 provided on the portion of the height side frame 41 facing the rear end of the front side frame 11B, into which the guide projection 91 is guided. The movement guide section 90 guides the movement of the front side frame 11B by having the guide projection 91 fit inside the guide groove 95.

[0074] As shown in Figures 12 to 14, the guide projection 91 is a guide pin (guide shaft) that protrudes inward from the inner surface of the front side frame 11B and is supported by the guide groove 95. Specifically, the guide projection 91 is positioned slightly forward of the frame pivot axis 15 and slightly below the frame pivot axis 15 in a side view of the seat.

[0075] As shown in Figures 12 to 15, the guide groove 95 is a groove formed by cutting out the upper portion of the height side frame 41 from the front to the rear, and supports the guide projection 91. The guide groove 95 may also be called a guide recess or guide hole. As shown in Figure 5, the guide groove 95 is formed in the height side frame 41, so that the guide projection 91 is supported by the guide groove 95 without being affected by the raising and lowering movements of the first height link 31 and the second height link 32 located below the height side frame 41.

[0076] As shown in Figure 15, the guide groove 95 has an opening 96 formed on the front surface of the height side frame, a first groove 97 extending rearward from the opening 96, a second groove 98, and a third groove 99. The opening 96 and grooves 97, 98, and 99 are formed to correspond to the movement path (movement trajectory) of the guide projection 91, which is linked to the switching operation of the seat body (seat cushion 1).

[0077] A chamfered portion 96a is formed on the periphery of the opening 96 to facilitate the insertion of the guide projection 91. The first groove 97 is formed continuously from the rear end of the opening 96 and extends rearward while being slightly inclined downward. The second groove 98 is formed continuously from the rear end of the first groove 97 and extends rearward with a slight upward inclination. The guide groove 95 (second groove 98) extends behind the back pivot axis 5b. The third groove 99 is formed continuously from the rear end of the second groove 98 and extends rearward while being slightly inclined downward.

[0078] As shown in Figures 16 to 18, when the seat back 2 rotates to the rear of the seat cushion 1, the rear side frame 11A and the front side frame B move in conjunction with the movement of the seat back 2 so that they are aligned in the front-to-back direction of the seat. At this time, the movement of the rear side frame 11A is restricted by the movement restricting unit 80, and the movement of the front side frame 11B is guided by the movement guide unit 90, causing the rear end of the front side frame 11B and the frame pivot axis 15 to rise slightly. This allows the seat cushion 1 and seat back 2 to be moved to a more horizontal position (full flat position).

[0079] Figure 16 is a side view of the movement restricting section 80 and the movement guide section 90 (guide protrusion 91, guide groove 95) when the sheet body is in the "normal state". The guide projection 91 is located in the first groove 97 and is supported by the first groove 97. This allows the seat cushion 1 and seat back 2 to be more stable in the "normal state" shown in Figure 16. Furthermore, when the seat back 2 rotates further backward, it moves from the first groove 97 to the second groove 98.

[0080] Figure 17 is a side view of the movement restricting section 80 and the movement guide section 90 when the seat body is in the "reclining state". The guide projection 91 is located in the second groove 98 and is supported by the second groove 98. This allows the seat cushion 1 and seat back 2 to be more stable when the seat is in the "reclining position". In particular, when the seat cushion 1 and seat back 2 move to a "flat state," the rear end of the front side frame 11B rises slightly, and a guide groove 95 (second groove 98) is formed to correspond to this upward movement of the rear end of the front side frame 11B. This allows the folding mechanism of the seat cushion 1 to operate smoothly. Furthermore, when the seat back 2 rotates further backward, it moves from the second groove 98 to the third groove 99.

[0081] Figure 18 is a side view of the movement restricting section 80 and the movement guide section 90 when the seat body is in a "flat state". The guide projection 91 is located in the third groove 99 and is supported by the third groove 99. Specifically, the top, side, and bottom surfaces of the guide projection 91 are in contact with the inner wall surface of the third groove 99. This allows the seat cushion 1 and seat back 2 to be more stable when in the "flat position". Here, as shown in Figure 18, when the seat cushion 1 and seat back 2 move from the "reclined state" to the "flat state," the rear end 11Be of the front side frame 11B rises slightly. Also, when it becomes the "flat state," the entire rear side frame 11A lowers (sags), and as a result, the entire front side frame 11B also lowers slightly. The second groove 98 and the third groove 99 are formed to correspond to this movement path of the front side frame 11B. Specifically, the third groove 99 extends rearward while being slightly inclined downward. As a result, the folding mechanism of the seat cushion 1 (side frames 11A, 11B) is guided more smoothly, and the seat cushion 1 can be held in place by the moving guide section 90.

[0082] Figure 19 is a side view of the movement restricting section 80 and the movement guide section 90 when the seat body is in the "folded state". At this time, the guide projection 91 is detached from the guide groove 95.

[0083] In the above configuration, as shown in Figures 13 and 15, the guide groove 95 is positioned to overlap with the back pivot axis 5b when viewed from above the seat. Furthermore, the guide groove 95 is positioned in the seat width direction between the seat back 2 (side connecting frame 26) and the front side frame 11B of the seat cushion 1. This allows each component to be compactly arranged in both the front-to-back and width directions of the seat.

[0084] In the above configuration, as shown in Figures 14 and 15, the height frame 40 is equipped with a height cover 45 that covers the height side frame 41 from the outside in the seat width direction. The height cover 45 is positioned between the height side frame 41 and the front side frame 11B in the seat width direction. In the height cover 45, a second guide groove 46 is formed along the guide groove 95 in the portion facing the guide groove 95. The movement guide section 90 guides the movement of the front side frame 11B by having the guide projection 91 fit inside both the guide groove 95 and the second guide groove 46. This allows the height side frame 41 to be covered by the height cover 45, improving the appearance of the outer surface of the vehicle seat S. In particular, it prevents the metal height side frame 41 from being exposed when the state of the vehicle seat S is changed.

[0085] <Manufacturing method for vehicle seats> Next, the manufacturing method for the vehicle seat S will be explained based on Figures 1 to 19. Regarding the manufacturing method of the vehicle seat S, explanations of manufacturing processes other than those listed below will be omitted. The vehicle seat S comprises a seat cushion 1, a seat back 2, and a reclining device 5 that rotates the seat back 2 behind the seat cushion 1.

[0086] First, prepare seatback 2 and attach seatback 2 to the vehicle. At this time, the seat back 2 is assembled via the reclining device 5 so that it can rotate relative to the floor of the vehicle. The seat back 2 can be rotated relative to the floor of the vehicle by the reclining device 5.

[0087] Next, prepare seat cushion 1 and attach seat cushion 1 to seat back 2. The cushion frame 10, which forms the framework of the seat cushion 1, has cushion side frames 11. The cushion side frame 11 includes a rear side frame 11A connected to the seat back 2, a front side frame 11B located in front of the rear side frame 11A, and a frame pivot shaft 15 that connects these side frames 11A and 11B so that they can rotate relative to each other.

[0088] When assembling the seat cushion 1 to the seat back 2, the rear side frame 11A and the front side frame 11B are configured to align in the front-to-back direction as the seat back 2 moves backward. Furthermore, the vehicle seat S is provided with a movement restriction section 80 and a movement guide section 90. When the seat back 2 rotates to the rear of the seat cushion 1, the movement restricting unit 80 restricts the movement of the rear side frame 11A, and the movement guide unit 90 guides the movement of the front side frame 11B. As a result, the front side frame 11B moves such that its rear end rises slightly.

[0089] The above manufacturing method makes it possible to produce a vehicle seat S that can be arranged between the "normal state" shown in Figures 1 to 3 and the "flat state" shown in Figure 4. In other words, when the seat back 2 rotates to the rear of the seat cushion 1, the folding mechanism of the seat cushion 1 can be operated smoothly.

[0090] <Vehicle seat according to the second embodiment> Next, the vehicle seat S2 of the second embodiment will be described with reference to Figures 20 to 25. Note that explanations that overlap with the vehicle seat S mentioned above will be omitted.

[0091] As shown in Figures 24 and 25, the vehicle seat S2 is equipped with a movement guide section 90A that guides the movement of the rear portion (rear side frame 11A) of the seat cushion 1 when switching from the "normal state" to the "flat state". By utilizing the movable guide section 90A (guide protrusion 91A, guide groove 95A), the seat can be arranged smoothly. The vehicle seat S2 may or may not be equipped with a movement restricting section 80 that restricts the movement of the seat cushion 1.

[0092] As shown in Figures 20 to 23, the vehicle seat S2 mainly comprises a seat cushion 1 (cushion frame 10), a seat back 2 (back frame 20), a rail device 4, a reclining device 5, a height device 30A (height frame 40A), and a movement guide section 90A.

[0093] The cushion frame 10 includes a rear side frame 11A, a front side frame 11B, and a frame pivot shaft 15. The rear side frame 11A is rotatably connected to the front side frame 11B via a frame pivot shaft 15. Furthermore, the rear side frame 11A is rotatably connected to the back frame 20 (side connecting frame 26) via a cushion pivot shaft 51. A guide projection 91A is formed on the inner surface of the front portion of the rear side frame 11A. As shown in Figure 22, the front side frame 11B is positioned forward of the guide projection 91A. As shown in Figures 22 and 23, the rear side frame 11A and the front side frame 11B are positioned directly above the rail device 4 and the height device 30A (second height bracket 37A), respectively.

[0094] The back frame 20 is attached to the lower end of the back side frame 21 and includes a side connecting frame 26 that connects the back side frame 21 and the height side frame 41. The side connecting frame 26 is connected to the rear side frame 11A via a cushion pivot shaft 51, and is also connected to the height side frame 41A (second height side frame 41b) via a back pivot shaft 5b.

[0095] As shown in Figures 20 to 23, the height device 30A is fixed to the upper surface of the rail device 4 (upper rail 4b) and includes a first height bracket 36A (see Figure 2) that connects the rail device 4 and the first height link 31A, and a second height bracket 37A that connects the rail device 4 and the second height link 32A. The second height bracket 37A includes a rail bracket body 37a, an inner flange 37b extending downward from the inner end of the rail bracket body 37a, and an outer flange 37c extending upward from the outer end of the rail bracket body 37a. The first height bracket 36A has a similar configuration.

[0096] As shown in Figure 23, the second height link 32A extends in the vertical direction and connects the second height bracket 37A (inner flange 37b) and the height frame 40A (first height side frame 41a). The height adjustment device 30A allows the height of the seat body to be adjusted, with the second height link 32A acting as the drive link and the first height link 31 (Figure 2) acting as the driven link. The height adjustment device 30A further includes a height frame 40A that supports the seat cushion 1 and seat back 2 from below.

[0097] As shown in Figures 20 to 23, the height frame 40A includes left and right height side frames 41A, a front connecting frame 42 (Figure 2), a central connecting frame 43 (Figure 2), a rear connecting frame 44 (Figure 2), and a second height connecting frame 47A. The height side frame 41A includes a first height side frame 41a that is elongated in the front-rear direction, and a second height side frame 41b that is attached to the rear portion of the first height side frame 41a.

[0098] As shown in Figures 20 and 23, the first height side frame 41a has a frame body, an upper flange 41aa, a lower flange 41ab, and a height connecting hole 41ac. The second height side frame 41b has a frame body, a height connecting hole 41ba, and a back connecting hole 41bb. The second height side frame 41b is connected by the second height connecting frame 47A with the height connecting holes 41ba and 41ac in communication. Furthermore, the second height side frame 41b is connected by a back pivot shaft 5b with the back connecting hole 41bb and the connecting hole of the side connecting frame 26 in communication. A guide groove 95A (also referred to as a guide recess or guide flange) is formed on the outer edge of the second height side frame 41b.

[0099] As shown in Figures 21 to 25, the movement guide section 90A is a member that guides the movement of the rear portion (rear side frame 11A) of the seat cushion 1 (cushion frame 10) when the seat body switches from the "normal state" to the "flat state". The movable guide section 90A includes a guide projection 91A provided on the front portion of the rear side frame 11A, and a guide groove 95A formed on the outer edge portion of the second height side frame 41b, into which the guide projection 91A is guided.

[0100] The guide projection 91A is a guide pin (guide shaft) that protrudes inward from the inner surface of the rear side frame 11A and is supported by the guide groove 95A. Specifically, the guide projection 91A is positioned slightly behind the frame pivot axis 15 and slightly below the frame pivot axis 15 in a side view of the seat.

[0101] The guide groove 95A is a groove formed along the outer edge portion of the second height side frame 41b and supports the guide projection 91. The guide groove 95A may also be referred to as a guide recess or guide flange.

[0102] As shown in Figure 24, the guide groove 95A has an opening 95Aa formed on the front surface of the second height side frame 41b, a first groove portion 95Ab extending rearward from the opening 95Aa, and a second groove portion 95Ac extending continuously from the first groove portion 95Ab. The first groove 95Ab and the second groove 95Ac are formed to correspond to the movement path of the guide projection 91A, which is linked to the switching operation of the sheet body.

[0103] The first groove 95Ab is formed continuously from the opening 95Aa and extends rearward while being slightly inclined downward. The second groove 95Ac is formed continuously from the rear end of the first groove 97 and extends downward while being slightly inclined forward.

[0104] As shown in Figure 25, when the seat back 2 rotates to the rear of the seat cushion 1, the rear side frame 11A and the front side frame B move in conjunction with the movement of the seat back 2 so that they are aligned in the front-to-back direction of the seat. At this time, the movement of the rear side frame 11A is guided by the movement guide unit 90A, causing the rear end of the front side frame 11B and the frame pivot axis 15 to rise slightly. This allows the seat cushion 1 and seat back 2 to transition to a more horizontal position (full flat position).

[0105] Figure 24 is a side view of the movement guide section 90A (guide protrusion 91A, guide groove 95A) when the sheet body is in the "normal state". The guide projection 91A is located in the first groove 95Ab and is supported by the first groove 95Ab. Specifically, the guide projection 91A abuts against the inner wall surface of the first groove 95Ab. As a result, the seat cushion 1 and seat back 2 are more stably supported in the "normal state" shown in Figure 24. Furthermore, as the seatback 2 rotates further backward, it moves from the first groove 95Ab to the second groove 95Ac.

[0106] Figure 25 is a side view of the movement guide section 90 when the seat body is in a "flat state". The guide projection 91A abuts against the second groove 95Ac and is supported by the second groove 95Ac. Specifically, the guide projection 91A abuts against the inner wall surface of the second groove 95Ac. The guide projection 91A may also be supported at the corners of the first groove 95Ab and the second groove 95Ac. This allows the seat cushion 1 and seat back 2 to be supported more stably when the seat is in a "flat position".

[0107] Even with the above-mentioned vehicle seat S2, when the seat back 2 rotates to the rear of the seat cushion 1, the rotation mechanism of the seat cushion 1 can operate smoothly. Specifically, the folding mechanism of the seat cushion 1 (side frames 11A, 11B) is guided more smoothly, and the seat cushion 1 can be held in place by the movement guide part 90A. Furthermore, when the vehicle seat is subjected to an impact from below while the vehicle is in motion (it may also be subjected to an impact from the front or rear), the rear side frame 11A and the front side frame 11B are prevented from unintentionally folding in the middle, thereby preventing a decrease in the seating comfort of the vehicle seat. In other words, by providing the movement guide section 90A (guide protrusion 91A, guide groove 95A), it is possible to prevent the folding mechanism from operating unintentionally.

[0108] <Other> In the above embodiment, as shown in Figures 17 and 18, when the seat back 2 rotates to the rear of the seat cushion 1, the rear side frame 11A and the front side frame 11B move in conjunction with the movement of the seat back 2 so that they are aligned in the front-to-back direction of the seat. In this case, "aligned in the front-to-back direction of the seats" does not necessarily mean that the rear side frame 11A and the front side frame 11B are horizontal (or nearly horizontal). The rear side frame 11A may be slightly inclined relative to the front side frame 11B. In other words, "the rear side frame 11A and the front side frame 11B are aligned in the front-to-back direction of the seat" should include not only the "flat state" shown in Figure 18, but also the "reclined state" shown in Figure 17.

[0109] In the above embodiment, as shown in Figures 12 and 13, the movable guide section 90 is provided on the front side frame 11B and the height side frame 41, respectively, but is not particularly limited. The movable guide section 90 may be provided on the front side frame 11B and the rear side frame 11A, or on the front side frame 11B and the side connecting frame 26. Alternatively, the movable guide section 90 is not limited to the configuration of a guide projection 91 and a guide groove 95. For example, the movable guide section 90 may simply be provided only on the height side frame 41, or only on the rear side frame 11A, or only on the side connecting frame 26.

[0110] In the above embodiment, as shown in Figures 12 and 13, the guide projection 91 is provided on the front side frame 11B and the guide groove 95 is provided on the height side frame 41, but the reverse configuration is also possible. The guide projection 91 may be provided on the height side frame 41, and the guide groove 95 may be provided on the front side frame 11B. In that case, it is preferable that the guide projection 91 protrudes from the outer surface of the height side frame 41. Also, it is preferable that the guide groove 95 is formed by cutting out a notch from the rear surface of the front side frame 11B toward the front.

[0111] In the above embodiment, as shown in Figures 5 and 6, the vehicle seat S is switchable between a "normal state," a "raised state," and a "folded state," but is not particularly limited. In other words, the vehicle seat S only needs to be switchable between at least a "normal state" and a "reclining state (flat state)".

[0112] In the above embodiment, as shown in Figure 2, the vehicle seat S is equipped with a height adjustment device 30, but it is not necessary for the vehicle seat to be equipped with a height adjustment device 30. In that case, the vehicle seat S may be equipped with a "base member" instead of a height adjustment device 30. The "base member" may be equipped with a base frame that forms the skeleton, and the base frame may be equipped with "base side frames" that are spaced apart in the width direction of the seat. Furthermore, it is preferable that guide grooves 95 be formed in the "base side frame".

[0113] In the above embodiment, a vehicle seat (automobile seat) was described as a specific example, but it is not particularly limited and can be used as a seat for vehicles such as trains and buses, as well as for vehicles such as airplanes and ships.

[0114] The above embodiments mainly described a vehicle seat according to the present invention. However, the embodiments described above are merely examples to facilitate understanding of the present invention and do not limit it. The present invention can be modified and improved without departing from its spirit, and of course, equivalents thereof are included. [Explanation of Symbols]

[0115] <First Embodiment> S Vehicle Seat Sa Seat Body SF Seat Frame 1 seat cushion 1a Pad material 1b Skin material 2 seatbacks 2a Pad material 2b Skin material 3 Headrests 3a Head pillar 3b Pad material 3c Skin material 4 Rail device 4a Lower Rail 4b Apparel 4c locking component 4D rail control lever 5. Reclining device 5a Reclining chair body 5b Back rotation axis 5c spiral spring 5d Reclining control lever 10 Cushion Frames 11 Cushion side frame 11A Rear side frame 11Aa, 11Ba Frame Body 11Ab, 11Bb Reinforcement flange 11Ac, 11Bc mating flange 11Ad, 11Bd Reinforcement flange 11B Front side frame 11Be rear end 12 Pan Frames 13 Connecting pipes 14 Pressure-receiving member 15 Frame pivot axis 16, 17 Lever mounting bracket 20 Backframe 21 Backside Frame 22 Upper frame 23 Lower frame 24 Member Frame 25 Board Frames 26 Side connecting frame 26a Rotating bracket 26b Protrusion 27 Pillar retaining member 28 Lever mounting bracket 30 Height adjustment device (base component) 31. First Height Link 32. Second Height Link 33. Third Height Link 34 Locking member 35 Height adjustment lever 36. First height bracket 37. Second height bracket 38 Link pivot axis 40 Height Frame (Base Frame) 41. Height side frame (base side frame) 42 Front connecting frame 43 Central connecting frame 44 Rear connecting frame 45 Height Cover 46. ​​Second guide groove 50 Cushion locking device 51 Cushion pivot axis 60 Lock Unit 61 Axle fixing plate 61a Engagement groove 62 Locking Actuation Plate 62a Plate base 62b Plate rotation axis 62c lock piece 62d Window opening 62e Engaged surface 63 Elastic rubber 70 Unlock Unit 71 Operating Arm 71a Arm base 71b Bent part 71c Arm rotation axis 71d Flexible engaging piece 71e Contact part 71f Spring fixing part 72 Release actuation member 73 Rotating Plates 73a Circular section 73b Extension part 73c Release actuation piece 74 Rotation transmission member 74a Fixed flange 74b Cylindrical section 74c Abutted part 75 Spring 76 Inner cover 77 Outer cover 80 Movement Control Department 90 Mobile Guide Section 91 Guide protrusion 95 Guide groove 97 First groove 98 Second trench section 99 Third groove <Second Embodiment> S2 Vehicle Seat 1 seat cushion 2 seatbacks 4 Rail device 5. Reclining device 5b Back rotation axis 10 Cushion Frames 11 Cushion side frame 11A Rear side frame 11B Front side frame 15 Frame pivot axis 20 Backframe 21 Backside Frame 26 Side connecting frame 30A Height adjustment device (base component) 31A First Height Link 32A Second Height Link 36A First Height Bracket 37A Second Height Bracket 37a Rail bracket body 37b Inner flange 37c outer flange 40A Height Frame 41A Height Side Frame 41a First height side frame 41aa Upper flange 41ab Lower flange 41ac Height connecting hole (connecting part) 41b Second Height Side Frame 41ba Height connecting hole (connecting part) 41bb Back connecting hole (connecting part) 47A Second Height Connecting Frame 50 Cushion locking device 51 Cushion pivot axis 90A Mobile Guide Unit 91A Guide protrusion 95A Guide groove (guide recess, guide flange) 95Aa opening 95Ab First groove (first guide recess) 95Ac Second groove (second guide recess)

Claims

1. A vehicle seat comprising a seat cushion, a seat back, and a reclining device that rotates the seat back behind the seat cushion, The aforementioned seat cushion is equipped with a cushion frame that forms its skeleton, The cushion frame has cushion side frames that are spaced apart in the width direction of the seat, The aforementioned cushion side frame is A rear side frame connected to the aforementioned seat back, A front side frame located in front of the aforementioned rear side frame, The rear side frame and the front side frame are connected to each other by a frame pivot shaft that allows them to rotate relative to each other. When the seat back rotates to the rear of the seat cushion, the rear side frame and the front side frame move in conjunction with the movement of the seat back so that they are aligned in the front-to-back direction of the seat. The aforementioned vehicle seat is, A movement restricting unit that restricts the movement of the rear side frame when the rear side frame and the front side frame move so that they are aligned in the front-rear direction of the seat, The system further includes a movement guide section that guides the movement of the front side frame when the rear side frame and the front side frame move so that they are aligned in the front-rear direction of the seat, A vehicle seat characterized in that the front side frame moves such that the rear end of the front side frame rises, as the movement of the rear side frame is restricted by the movement restricting part and the movement of the front side frame is guided by the movement guide part.

2. The reclining device switches the seat back between a normal position in which an occupant can sit and a flat position in which the seat back is rotated from the normal position to the rear of the seat cushion. When the seatback rotates to the flat position, As the seat back moves, the rear side frame and the front side frame move so that they are aligned in the front-to-back direction of the seat. The vehicle seat according to claim 1, characterized in that the movement restricting portion restricts the movement of the rear side frame and the movement guide portion guides the movement of the front side frame, thereby causing the rear end of the front side frame and the frame pivot axis to rise.

3. The seat cushion and / or the seat back is provided with a base member that supports it from below, The aforementioned moving guide unit is A guide projection is provided at the rear end of the front side frame, The base member has a portion facing the rear end of the front side frame, and includes a guide groove into which the guide projection is guided, The vehicle seat according to claim 1, characterized in that the guide projection fits into the inside of the guide groove, thereby guiding the movement of the front side frame.

4. The base member comprises a base frame that forms the skeleton, The base frame has base side frames that are spaced apart in the seat width direction, The aforementioned guide projection protrudes laterally from the side surface of the rear end of the front side frame, The guide groove is formed in the portion of the base side frame that faces the side surface of the rear end of the front side frame, The guide groove has a first groove portion extending in the front-rear direction of the sheet, and a second groove portion formed continuously from the rear end of the first groove portion and extending rearward while inclined upward. The aforementioned guide projection is When the seat back is in its normal state, it is located in the first groove, The vehicle seat according to claim 3, characterized in that the seat back moves from the first groove to the second groove when it rotates backward.

5. The guide groove is formed continuously from the rear end of the second groove and further has a third groove extending to the rear. The guide projection is located in the third groove when the seat back is in a flat position rotated to the rear of the seat cushion. The vehicle seat according to claim 4, characterized in that the moving guide portion guides the movement of the front side frame by the upper surface of the guide projection contacting the inner wall surface of the third groove.

6. The vehicle seat according to claim 5, characterized in that the third groove extends rearward from the rear end of the second groove while inclining downward.

7. The reclining device is attached to the base side frame and includes a back pivot shaft that serves as an axis for rotating the seat back relative to the base side frame. The vehicle seat according to claim 4, characterized in that the second groove portion of the guide groove extends further back than the back pivot axis.

8. The vehicle seat according to claim 7, characterized in that the guide groove is positioned to overlap with the back pivot axis when viewed from above the seat.

9. The aforementioned seat back is equipped with a back frame that forms the skeleton, The aforementioned back frame is The back side frames are arranged with spacing in the width direction of the seat, It has a side connecting frame attached to the rear end of the back side frame and connecting the back side frame and the base side frame, The vehicle seat according to claim 4, characterized in that the guide groove is positioned between the side connecting frame of the seat back and the front side frame of the seat cushion in the seat width direction.

10. The base member is a height adjustment device that raises and lowers the seat cushion relative to the vehicle floor, The base side frame is a height side frame that is arranged with spacing in the seat width direction and supports the seat cushion from below, The height device further includes a height link attached to the height side frame for raising and lowering the height side frame. The vehicle seat according to claim 4, characterized in that the guide groove is formed in the portion of the height side frame that faces the side surface of the rear end of the front side frame.

11. The reclining device switches the seat back between a normal state in which an occupant can sit, a flat state in which the seat back is rotated backward from the normal state, and a folded state in which the seat back is folded toward the seat cushion. The vehicle seat according to claim 10, characterized in that the height link operates to tilt the seat cushion forward in conjunction with the movement of the seat back when the seat back rotates from the normal state to the folded state.

12. The aforementioned height side frame is provided with a height cover that covers it from the outside in the seat width direction, The height cover is positioned between the height side frame and the front side frame in the seat width direction. In the height cover, the portion facing the guide groove is provided with a second guide groove formed along the guide groove. The vehicle seat according to claim 10 or 11, characterized in that the moving guide portion guides the movement of the front side frame by having the guide projections fit into the guide groove and the second guide groove.

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