Vehicle seats

Abstract

To obtain a vehicle seat which can reduce protrusion of a buckle device to a seat front side in linkage with changes in seat shape.SOLUTION: A vehicle seat 10 comprises: a seat cushion 12 having a seating surface 12A; a seat back 14 which is located on a seat rear end side of the seat cushion 12, and has a backrest surface 14A; a buckle device 50 which is located on one side in a seat width direction of the seat cushion 12, and is connected to a vehicle body via a webbing 52; at least one rotary shaft which so supports at least one of the seat cushion 12 and the seat back 14 as to be rotatable around an axis in the seat width direction; and a power transmission part PW1 which converts torque around the rotary shaft into a pulling force toward a seat rear side, and transmits the same to the buckle device 50. The power transmission part PW1 pulls the buckle device 50 toward the seat rear side in linkage of rotation of the seat cushion 12 or the seat back 14.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a vehicle seat.

Background Art

[0002] Conventionally, in vehicle seats, various techniques capable of changing the seat form according to the usage state inside the vehicle cabin are known. When installing such a technique, it becomes a problem to reduce interference with a buckle device provided on the side of the vehicle seat when the seat form is changed.

[0003] In Patent Document 1 below, when reclining the backrest of a vehicle seat to a folded state, it is proposed to pivot the seat belt buckle forward and move it to a storage position.

[0004] In Patent Document 2 below, when rotating the seat cushion of a vehicle seat forward to a standing state, it is proposed to configure the seat belt buckle to automatically fall forward as the seat cushion rotates forward.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] Here, the greater the protrusion of the buckle device toward the front of the seat, the more likely it is to interfere with the seat back and seat cushion. Therefore, in conjunction with changes in the seat configuration, efforts are being made to reduce the protrusion of the buckle device toward the front of the seat. The technologies described in Patent Documents 1 and 2 above do not take this point into consideration, and therefore there is room for improvement.

[0007] In consideration of the above facts, the present invention aims to provide a vehicle seat that can reduce the protrusion of the buckle device toward the front of the seat in conjunction with a change in the seat configuration. [Means for solving the problem]

[0008] The vehicle seat of the present invention as described in claim 1 comprises a seat cushion having a seating surface, The seat cushion comprises a seat back having a backrest surface and positioned on the rear end side of the seat cushion, a buckle device positioned on one side of the seat cushion in the seat width direction and connected to the vehicle body via webbing, at least one rotating shaft that supports at least one of the seat cushion and the seat back so as to be rotatable around an axis in the seat width direction, and a power transmission unit that converts the rotational force around the rotating shaft into a pulling force toward the rear of the seat and transmits it to the buckle device, wherein the power transmission unit is configured to pull the buckle device toward the rear of the seat in conjunction with the rotation of the seat cushion or the seat back.

[0009] The vehicle seat of the present invention as described in claim 1 has at least one pivot axis that supports at least one of the seat cushion and the seat back so as to be rotatable around an axis in the seat width direction. The vehicle seat also includes a power transmission unit that converts the rotational force around the pivot axis into a pulling force toward the rear of the seat and transmits it to the buckle device. As a result, in the vehicle seat, the buckle device can be pulled toward the rear of the seat in conjunction with the rotation of the seat cushion or seat back. Consequently, the protrusion of the buckle device toward the front of the seat can be reduced when the seat cushion or seat back is rotated due to a change in the seat configuration, and interference between the seat cushion or seat back and the buckle device can be suppressed.

[0010] The vehicle seat of the present invention as described in claim 2, in the configuration described in claim 1, wherein the power transmission unit shortens the overall length of the buckle device, including the webbing, when the buckle device is pulled towards the rear of the seat.

[0011] In the vehicle seat of the present invention as described in claim 2, the overall length of the buckle device, including the webbing, can be shortened when the buckle device is retracted towards the rear of the seat, so that the buckle device can be miniaturized when changing the design. As a result, it becomes easier to secure storage space for the buckle device in the lower part of the seat, and the constraints on the seat design can be reduced.

[0012] The vehicle seat of the present invention as described in claim 3, in the configuration described in claim 1 or claim 2, wherein the power transmission unit rotates the buckle device around an axis in the tongue insertion direction and pulls it toward the rear of the seat.

[0013] In the vehicle seat of the present invention as described in claim 3, the buckle device can be rotated around the axis in the tongue insertion direction and pulled towards the rear of the seat. Therefore, interference with surrounding members can be reduced, for example, by changing the orientation of the buckle device to one that reduces the thickness in the vertical direction of the seat.

[0014] The vehicle seat of the present invention as described in claim 4 has the configuration described in claim 1 or claim 2, wherein the rotation axis has a first rotation axis that supports the seat cushion so as to be rotatable around an axis in the seat width direction, and a second rotation axis that supports the seat back so as to be rotatable around an axis in the seat width direction, the seat cushion is configured to be set by rotating around the first rotation axis to a seating position that supports the buttocks of an occupant seated on the seat cushion, and a flipped-up position in which the seating surface is positioned toward the front of the seat, and the seat back is configured to be set by rotating around the second rotation axis to a backrest position that supports the back of an occupant seated on the seat cushion, and a forward-tilting position in which the backrest surface is positioned toward the lower side of the seat.

[0015] The vehicle seat of the present invention as described in claim 4 is a double-folding type seat that can be folded by setting the seat cushion in the flipped-up position and the seat back in the forward-folded position. As a result, when changing the seat configuration of the vehicle seat to the double-folding state, the buckle device can be pulled towards the rear of the seat in conjunction with the rotational operation performed on the seat cushion or seat back. [Effects of the Invention]

[0016] As described above, in the vehicle seat according to the present invention, the protrusion of the buckle device toward the front of the seat can be reduced in conjunction with changes in the seat configuration. [Brief explanation of the drawing]

[0017] [Figure 1] This is a side view showing the normal usage state of a vehicle seat according to the first embodiment. [Figure 2] This is a side view showing the double-folding state of a vehicle seat according to the first embodiment. [Figure 3]FIG. 1 is a side view showing a buckle device in a state where a seat back of a vehicle seat according to the first embodiment is set to a backrest position, with a part of a boot case cut away. [Figure 4] FIG. 2 is a side view showing a buckle device in a state where a seat back of a vehicle seat according to the first embodiment is set to a forward-falling position, with a part of a boot case cut away. [Figure 5] FIG. 3 is a side view of a main part for explaining an operation in which the buckle device is rotated and drawn into the rear side of the seat in conjunction with the rotation of the seat back. (A) shows a protruding state of the buckle device, and (B) shows a drawn-in state of the buckle device. [Figure 6] FIG. 4 is a side view showing a buckle device in a state where a seat back of a vehicle seat according to the second embodiment is set to a backrest position. [Figure 7] FIG. 5 is a side view showing a buckle device in a state where a seat back of a vehicle seat according to the second embodiment is set to a forward-falling position. [Figure 8] FIG. 6 is a side view showing a normal use state of a vehicle seat according to the third embodiment. [Figure 9] FIG. 7 is a side view showing a buckle device in a state where a seat back of a vehicle seat according to the third embodiment is set to a backrest position. [Figure 10] FIG. 8 is a side view showing a buckle device in a state where a seat back of a vehicle seat according to the third embodiment is set to a forward-falling position.

BEST MODE FOR CARRYING OUT THE INVENTION

[0018] <First Embodiment> The vehicle seat 10 according to the first embodiment will be described below with reference to Figures 1 to 5. In each figure, arrows FR indicate the forward direction of the seat, and arrows UP indicate the upward direction of the seat. Unless otherwise specified, in this embodiment, the front-rear direction, up-down direction, and left-right direction (seat width direction) of the vehicle seat 10 coincide with the front-rear direction, up-down direction, and left-right direction of the vehicle (automobile) on which the vehicle seat 10 is mounted. Note that in some figures, reference numerals have been omitted for clarity.

[0019] The vehicle seat 10 according to this embodiment is, for example, a double-folding type seat and is positioned as a rear seat in a vehicle of the type such as a wagon or hatchback. In this double-folding type vehicle seat 10, by pulling the seat cushion forward and then folding the seat back forward, the back of the seat back becomes a flat cargo area. This allows the rear space of the vehicle interior to be converted into a cargo area by folding the seat back. In other words, the vehicle seat 10 can change its seat configuration between a normal use state in which an occupant is seated on the seat cushion and a double-folding state in which the rear space of the vehicle interior is converted into a cargo area by folding the seat back.

[0020] Furthermore, in this embodiment, the buckle device provided on the side of the seat cushion can be folded forward and stored in conjunction with the operation of folding the seat back forward. At this time, the buckle device is moved to the storage position by rotating it around the axis in the tongue insertion direction and pulling it towards the rear of the seat. As a result, the buckle device is positioned so as to reduce the thickness in the vertical direction of the seat, and is stored in a position where it protrudes less towards the front of the seat compared to the normal use state. The details of the vehicle seat 10 will be described below.

[0021] Figure 1 is a side view showing the vehicle seat 10 in its normal use state, and Figure 2 is a side view showing the vehicle seat 10 in its double-folded state. As shown in these figures, the vehicle seat 10 includes a seat cushion 12 that supports the buttocks and thighs of the seated occupant, a seat back 14 that supports the back of the seated occupant, and a headrest 16 that supports the head of the seated occupant.

[0022] (Seat cushion) The seat cushion 12 consists of a cushioning material such as foamed urethane, covered with a surface material not shown, supported by a metal frame. As shown in Figure 1, in normal use, the seating surface 12A of the seat cushion 12 is positioned facing upwards towards the seat. The lower part of the seat cushion 12 is connected to the vehicle floor via a cushion rotation support part 20. The cushion rotation support part 20 rotatably connects the front end of the seat cushion 12 to the vehicle floor (not shown). As a result, the seat cushion 12 is rotatable around an axis in the seat width direction between a seating position that supports the buttocks of an occupant seated on the seat cushion 12 (see Figure 1) and a flipped-up position (see Figure 2) where the seating surface 12A is positioned facing forward towards the seat.

[0023] As an example, the cushion rotation support section 20 includes a front anchor bracket 22 fixed to the floor of the vehicle body (not shown), a guide bracket 24 supported by the front anchor bracket 22, and a cushion rotation link 28 supported by the guide bracket 24 so as to be rotatable around a first rotation axis 26.

[0024] The front anchor brackets 22 are provided in pairs on the left and right sides of the seat cushion 12 and are fixed to the floor of the vehicle body using anchor bolts 30.

[0025] A guide bracket 24 is attached to the upper part of the front anchor bracket 22. This guide bracket 24 has an inverted U-shaped guide groove 32 formed on its side surface facing outward in the sheet width direction. One end of a guide pin 34, whose axial direction is in the sheet width direction, is slidably supported in this guide groove 32.

[0026] A cushion rotation link 28 is positioned on the outside of the guide bracket 24 in the seat width direction. The cushion rotation link 28 is provided in a left-right pair relative to the seat cushion 12 and extends in the seat front-rear direction. The front ends of the left-right pair of cushion rotation links 28 are rotatably connected to both ends of a bracket (not shown) that extends in the seat width direction via a first rotation shaft 26. The first rotation shaft 26 has its axial direction in the seat width direction and is provided in a left-right pair relative to the seat cushion. The rear ends of the left-right pair of cushion rotation links 28 are connected via a third rotation shaft 36 through a bracket (not shown) that extends in the seat width direction. With this configuration, a rectangular frame is formed by the left-right pair of cushion rotation links 28 and a pair of front and rear brackets that connect the front ends and rear ends of the pair of cushion rotation links 28. The rear ends of the left-right pair of cushion rotation links 28 are attached to the rear end side of the seat cushion 12 via a bracket that connects the rear ends.

[0027] Here, the front ends of a pair of left and right cushion rotation links 28 are fixed to the other end of a guide pin 34 supported by a guide bracket 24. The guide pin 34 slides within an inverted U-shaped guide groove 32 in conjunction with the movement that rotates the front end of the seat cushion 12 around the first rotation axis 26. As a result, as shown in Figure 2, the entire seat cushion 12 is guided toward the front of the seat as it moves along the guide groove 32, and the rear end of the seat cushion 12 is raised and set in the flipped-up position. When the seat cushion 12 is set in the flipped-up position, the seating surface 12A is positioned facing toward the front of the seat.

[0028] (Seat back) The seat back 14 consists of a cushioning material such as foamed urethane covered with a surface material (not shown), supported by a metal seat back frame 40 (see Figure 3) which serves as a skeletal member. A headrest 16 is positioned at the upper end of the seat back 14. This headrest 16 is attached to the seat back frame 40 via stays (not shown).

[0029] As shown in Figure 1, in normal use, the backrest surface 14A of the seatback 14 is positioned facing forward towards the seat. The lower end of the seat cushion 12 is fixed to the floor of the vehicle body (not shown) via a hinge bracket 42. This hinge bracket 42 has a second rotation axis 44 with the seat width direction as its axis, and supports the seatback 14 so that it can rotate around the second rotation axis 44. As a result, the seatback 14 is rotatable around the axis in the seat width direction between a backrest position that supports the back of an occupant seated on the seatback 14 (see Figure 1) and a forward-tilted position (see Figure 2) where the backrest surface 14A is positioned facing downward towards the seat.

[0030] As shown in Figure 2, the seat cushion 12 is set to the flipped-up position, and then the seat back 14 is folded forward to achieve the double-folding state. In this state, the back of the seat back 14 becomes a flat cargo bed.

[0031] (Buckle device) As shown in Figure 3, the buckle device 50 is positioned on one side of the seat cushion 12 in the seat width direction. The buckle device 50 includes a buckle body 54 connected to the vehicle body via a long strip of webbing 52, a buckle boot 60 attached to the buckle body 54, and a boot case 70 attached to the buckle boot 60. Note that in Figure 3, the front end of the boot case 70 is partially cut out for clarity.

[0032] The buckle body 54 is shaped like a long box. The buckle body 54 is configured so that a tongue (not shown) can be inserted into and locked into the tip that protrudes toward the front of the seat. The buckle body 54 is provided with a release switch (not shown) for releasing the tongue, and by operating the release switch, the tongue can be released (pulled out) from the buckle body 54. Since the structure of the buckle body 54 is publicly known, a detailed explanation will be omitted.

[0033] Furthermore, a long, strip-shaped seat belt webbing is movably inserted through the tongue, and the base end of the seat belt webbing is wound onto a retractor (not shown) fixed to the vehicle. An anchor (not shown) fixed to the vehicle body is connected to the tip of the seat belt webbing. The seat belt webbing is movably inserted through a through anchor (not shown) between the tongue and the retractor, and the through anchor is supported by the vehicle above the seat. As a result, when the tongue is attached to the buckle body 54, the seat belt webbing is attached to the occupant seated in the vehicle seat 10.

[0034] On the other hand, one end of the webbing 52 and one end of the cable 58 are connected to the base end of the buckle body 54. The cable 58 constitutes the power transmission section PW1, which will be described later.

[0035] The webbing 52 has one end at the front connected to the buckle body 54 and the other end at the base connected to the rear anchor bracket 46. The rear anchor bracket 46 is fixed to the vehicle floor using anchor bolts 48, fastened together with the support bracket 56 (described later). In this way, the buckle body 54 is connected to the vehicle body via the webbing 52.

[0036] The buckle boot 60 is a long, cylindrical shape, through which the webbing 52 and cable 58 are inserted. The tip of the buckle boot 60 is provided with a buckle housing cylinder 62 for housing the buckle body 54. In the normal use state of the vehicle seat 10, the base end of the buckle body 54 is housed in the buckle housing cylinder 62. The tip end of the buckle body 54 protrudes from the buckle housing cylinder 62 toward the front of the seat.

[0037] Within the buckle housing cylinder 62, the space S1 formed between it and the buckle body 54 contains the connection points for the buckle body 54, the webbing 52, and the cable 58. A restricting member 63 is also located in space S1 to restrict the amount the buckle body 54 is retracted toward the rear of the seat. The restricting member 63 is, for example, a disc-shaped or spherical member attached to the middle of the cable 58.

[0038] The base end of the buckle boot 60 is provided with a spring mounting cylinder 64, which is cylindrical in shape and has a smaller diameter than the buckle housing cylinder 62. A coil spring 65, which serves as a biasing member, is loosely wound around the outer circumference of the spring mounting cylinder 64. Furthermore, on the base end side of the coil spring 65, a guide projection 66 is provided on the outer circumference of the spring mounting cylinder 64, projecting radially outward from the outer circumference (see Figures 3, 4, and 5(A)). This guide projection 66 is inserted into a rotation guide groove 76 formed in the boot case 70, which will be described later.

[0039] Here, the buckle housing cylinder portion 62 and the spring mounting cylinder portion 64 of the buckle boot 60 are separated by a plate-shaped partition portion 68. This partition portion 68 has a slit 69 formed through it in the direction of the plate thickness (see Figure 5(A)). The strip-shaped webbing 52 and the linear cable 58 extending from the buckle body 54 are inserted into the inside of the spring mounting cylinder portion 64 through the slit 69 of the partition portion 68. On the other hand, the restricting member 63 attached to the cable 58 in space S1 cannot be inserted through the slit 69 of the partition portion 68.

[0040] In this configuration, when the cable 58 is pulled towards the rear of the seat with a predetermined tensile force, the buckle body 54 is pulled into the buckle housing cylinder 62 of the buckle boot 60. Subsequently, if the amount of cable pulled in exceeds a predetermined amount, the restricting member 63 is locked into the slit 69, restricting the amount of the buckle body 54 pulled into the buckle housing cylinder 62.

[0041] The coil spring 65 is housed in the space S2 formed between the partition portion 68 of the buckle boot 60, the spring mounting cylinder portion 64, and the boot case 70, which will be described later. As described above, if the amount of cable 58 pulled towards the rear of the seat exceeds a predetermined amount, the restricting member 63 is locked into the slit 69. Next, the restricting member 63 presses the partition portion 68 in the axial direction. As a result, the coil spring 65 in the space S2 is compressed, and the compressed coil spring 65 biases the buckle boot 60 toward the front of the seat.

[0042] The boot case 70 is a long cylindrical shape and is attached to the outer circumference of the buckle boot 60. The tip of the boot case 70 is provided with a spring housing cylinder 72 that covers the tip of the spring mounting cylinder 64 of the buckle boot 60. This spring housing cylinder 72, together with the spring mounting cylinder 64 of the buckle boot 60, forms a space S2, and the coil spring 65 is housed in space S2.

[0043] A rotating guide cylinder portion 74 is formed in the boot case 70 adjacent to the spring housing cylinder portion 72. The rotating guide cylinder portion 74 is a long cylinder with a smaller diameter than the spring housing cylinder portion 72 and covers the base end side of the spring mounting cylinder portion 64. A rotating guide groove 76 is formed in the rotating guide cylinder portion 74 through which a guide projection 66 provided on the outer circumferential surface of the spring mounting cylinder portion 64 is inserted. The rotating guide groove 76 extends spirally along the outer circumferential surface of the rotating guide cylinder portion 74. When the buckle boot 60 is pulled into the boot case 70 due to the compression of the coil spring 65, the guide projection 66 protruding from the spring mounting cylinder portion 64 slides along the rotating guide groove 76 and rotates the buckle boot 60. As a result, the buckle body 54 supported by the buckle boot 60 is pulled towards the rear of the seat and rotates around the axis in the tongue insertion direction.

[0044] Here, as shown in Figure 3, the boot case 70 is supported by a support bracket 56 fixed to the floor of the vehicle body (not shown) and a torsion spring 57 as a biasing member. The support bracket 56 is fixed to the floor of the vehicle body in a manner in which it is fastened together with a rear anchor bracket 46, and has a pair of vertical wall portions 56A that face each other in the seat width direction on either side of the boot case 70. Each of the pair of vertical wall portions 56A is provided with a support shaft 56B that protrudes toward the boot case 70. The torsion spring 57 is loosely wound around these support shafts 56B. That is, the torsion spring 57 is provided in a pair on either side of the boot case 70. One end of the torsion spring 57 is locked to the corresponding vertical wall portion 56A, and the other end of the torsion spring 57 is locked in contact with the bottom surface of the spring housing cylinder portion 72 of the boot case 70. The pair of torsion springs 57 can be constructed from a single wire by connecting the other ends that are locked to the boot case 70.

[0045] When the seat back 14 is tilted forward, the boot case 70 is tilted around the support shaft 56B on an axis in the seat width direction by being pushed down by the seat back 14 (see Figure 4). In this state, the torsion spring 57 applies a biasing force to the tilted boot case 70 in the direction of raising the boot case 70. As a result, when the seat back 14 is returned from the tilted position to the backrest position, the biasing force of the torsion spring 57 causes the boot case 70 to stand upright. Furthermore, due to the elastic recovery of the coil spring 65 attached to the buckle boot 60, the buckle body 54 and the buckle boot 60 extend while rotating in the opposite direction around the axis in the tongue insertion direction.

[0046] (Power transmission section) Next, the power transmission unit PW1 installed in the buckle device 50 will be described. This power transmission unit PW1 converts the rotational force associated with the rotation of the seat back 14 into a pulling force toward the rear of the seat and transmits it to the buckle device 50. As shown in Figure 3, the power transmission unit PW1 consists of a cable 58 with one end connected to the buckle body 54, a buckle boot 60, a boot case 70, and a coil spring 65.

[0047] One end of the cable 58 in the direction of extension is connected to the buckle body 54, and the other end in the direction of extension is connected to the lower end of the seat back frame 40 via a fixing bracket 41. That is, the cable 58 extends from the buckle body 54 toward the rear of the seat, and at a position behind the seat back 14, its middle section is folded back via a bracket (not shown) and extends toward the front of the seat. The other end of the folded-back cable in the direction of extension is then connected to the lower end of the seat back frame 40.

[0048] As the seat back 14 rotates around the second pivot axis 44 and moves from the backrest position shown in Figure 3 to the forward-tilted position shown in Figure 4, the other end of the cable 58, connected to the seat back frame 40, moves forward towards the seat. Then, one end of the cable 58, connected to the buckle body 54, is pulled towards the rear of the seat. At this time, the backrest surface 14A of the seat back 14 presses the buckle device 50 downward towards the seat, tilting the buckle device 50 forward. As a result, the buckle device 50 is pulled towards the rear of the seat in conjunction with the rotation of the seat back 14, and tilted forward towards the seat with the support shaft 56B of the rear anchor bracket 46 as the pivot point.

[0049] Here, as shown in Figure 5(A), when one end of the cable 58 is pulled towards the rear of the seat, the buckle body 54 is pulled into the buckle boot 60, as shown in Figure 5(B). At this time, the cable 58 is pulled in through the slit 69 formed in the partition portion 68 that divides the inside of the buckle boot 60. As a result, the amount of the buckle body 54 protruding from the buckle boot 60 is reduced compared to the normal operating state.

[0050] Next, as shown in Figure 5(C), when the cable 58 is pulled in, the restricting member 63 is locked into the slit 69, and the restricting member 63 presses against the partition 68. This pressing force compresses the coil spring 65 attached to the buckle boot 60 (see Figure 4), and the buckle boot 60 is pulled into the boot case 70. At this time, the guide projection 66 protruding from the spring mounting cylinder portion 64 of the buckle boot 60 is guided into the rotation guide groove 76 provided in the rotation guide cylinder portion 74 of the boot case 70. As a result, the buckle boot 60 is pulled towards the rear of the seat and rotates around the axis in the tongue insertion direction. In this embodiment, as an example, when the seat back 14 is moved from the backrest position to the forward-tilted position, the buckle boot 60 and the buckle body 54 rotate by approximately 90 degrees.

[0051] By retracting the buckle boot 60, the amount of protrusion of the buckle boot 60 from the boot case 70 is reduced compared to normal use. In addition, the rotation of the buckle boot 60 changes the orientation of the buckle device 50 so that its thickness in the vertical direction of the seat is reduced.

[0052] (Mechanism of action and effect) As described above, in the vehicle seat 10 according to this embodiment, the power transmission unit PW1 rotates the buckle device 50 around the axis in the tongue insertion direction while pulling it in towards the rear and downward side of the seat in conjunction with the forward tilting operation of the seat back 14. As a result, when the seat configuration of the vehicle seat 10 is in the double-folding state, the buckle device 50 is stored in a position where its protrusion toward the front of the seat is smaller compared to the normal use state. By reducing the protrusion of the buckle device 50 toward the front of the seat, interference of the buckle device 50 when the seat configuration is changed can be reduced.

[0053] For example, in the double-folding state, the seat back 14 is positioned above the buckle device 50. Therefore, by reducing the protrusion of the buckle device 50 toward the front of the seat in conjunction with the forward tilting of the seat back 14, interference between the seat back 14 and the buckle device 50 can be reduced. This makes it easier to ensure a wide range of motion for the seat back 14. In addition, by changing the orientation of the buckle device 50 in a direction that reduces the thickness in the vertical direction of the seat in conjunction with the forward tilting of the seat back 14, the buckle device 50 is prevented from being pressed too hard against the backrest surface 14A of the seat back 14. This prevents indentations from being left on the backrest surface 14A by the buckle device 50 when the vehicle seat 10 is returned from the double-folding state to the normal use state.

[0054] Furthermore, in this embodiment, the cable 58 pulls the buckle body 54 toward the rear of the seat, thereby shortening the overall length L1 (see Figure 3) of the buckle device 50, including the webbing 52. This allows for space savings in the storage position of the buckle device 50 when it is in the storage position in the double-folding state, thereby increasing the flexibility of the seat design.

[0055] <Second Embodiment> The vehicle seat 100 according to the second embodiment will be described below with reference to Figures 6 to 7. Note that components identical to those in the first embodiment described above will be given the same numbers and their descriptions will be omitted. In this second embodiment, the buckle device 110 is pulled towards the rear of the seat and tilted forward in conjunction with the rotation of the seat back 14 toward the front of the seat by the power transmission unit PW2 set in the buckle device 110.

[0056] As shown in Figure 6, the buckle device 110 comprises a buckle body 54 connected to the vehicle body via a long strip-shaped webbing 52, and a buckle boot 112 attached to the buckle body 54. The buckle body 54 and the webbing 52 have the same configuration as in the first embodiment described above, so a detailed explanation is omitted. One end of the webbing 52 is connected to the buckle body 54, and the other end of the webbing 52 is fixed to the floor of the vehicle body (not shown) via a rear anchor bracket 114.

[0057] The buckle boot 112 is shaped like a long tube and is attached to the base end of the buckle body 54. As a result, the connection between the buckle body 54 and the webbing 52 is covered by the buckle boot 112.

[0058] The rear anchor bracket 114 has a vertical wall portion 114A erected on the upper side of the seat, to which the other end of the webbing 52 is connected. The vertical wall portion 114A also rotatably supports the rear end of the first bracket 116 which constitutes the power transmission section PW2.

[0059] (Power transmission section) The power transmission unit PW2 comprises a first bracket 116 supported by a rear anchor bracket 114, a second bracket 118 connecting the first bracket and the webbing 52, and a link arm 120 connecting the first bracket 116, the second bracket 118, and the rear end of the seat back 14.

[0060] The first bracket 116 is a long, plate-like shape and extends in the front-rear direction of the seat. The base end of the first bracket 116, which is located on the rear side of the seat, is rotatably supported via a support shaft 115 provided on the rear anchor bracket 114. The support shaft 115 is an axial member whose axis is oriented in the seat width direction, and it supports the first bracket 116 so that it can rotate around the axis in the seat width direction. A torsion spring 117 is attached to the support shaft 115, with one end locked to the rear anchor bracket 114 and the other end locked to the first bracket 116. Therefore, when the first bracket 116 rotates toward the front of the seat around the support shaft 115, it is biased toward the upward side of the seat by the torsion spring 117.

[0061] The first bracket 116 has a first guide hole 122 at its tip and a second guide hole 124 in the middle of its extension direction. The first guide hole 122 and the second guide hole 124 are elongated holes that extend in the extension direction of the first bracket 116.

[0062] The tip end of the first bracket 116 is connected to the second bracket 118 via the first guide hole 122. The second bracket 118 is elongated and plate-shaped, extending in the front-rear direction of the seat. The tip end of the second bracket 118, which is positioned on the front side of the seat, is attached to the webbing 52. The second bracket 118 also has a first slide shaft 132 provided in the middle of its extending direction and a second slide shaft 134 provided at its base end. The first slide shaft 132 is inserted into and locked in the first guide hole 122 of the first bracket 116, and is configured to slide within the first guide hole 122. The second slide shaft 134 is inserted into and locked in the second guide hole 124 of the first bracket 116, and is configured to slide within the second guide hole 124.

[0063] Here, the base end of the second bracket 118 is connected to one end of the link arm 120 via the second slide shaft 134. The link arm 120 has an arc shape when viewed in the seat width direction, and one end in the extending direction is connected to the lower end of the seat back 14 via the fixed bracket 41. One end of the link arm 120 is rotatable relative to the seat back 14 around an axis in the seat width direction. The other end of the link arm 120 is rotatably supported by the second slide shaft 134. As a result, the second bracket 118 is supported so as to be slidable approximately in the seat front-rear direction relative to the first bracket 116, with its base end, which is located on the rear side of the seat, connected to the link arm 120.

[0064] In the power transmission unit PW2 with the above configuration, as shown in Figure 7, when the position of the seat back 14 is set from the backrest position to the forward-tilted position, the other end of the link arm 120 moves to the rear and downward side of the seat in conjunction with the rotation of the seat back 14 toward the front of the seat. As a result, the second slide shaft 134 connected to the other end of the link arm 120 slides within the second guide hole 124, moving the second bracket 118 toward the rear of the seat. Consequently, the pulling force applied to the second bracket 118 toward the rear of the seat pulls the webbing 52 and the buckle body 54 toward the rear of the seat.

[0065] Furthermore, the downward movement of the link arm 120 pushes the first bracket 116 downwards towards the seat via the second slide shaft 134. This causes the entire buckle device 110, including the webbing 52, to rotate forward towards the seat around the support shaft 115 of the rear anchor bracket 114, thereby tilting it forward.

[0066] Subsequently, when the seat back 14 is returned from the forward-folded position to the backrest position, the buckle device 110, together with the first bracket 116, is raised upwards towards the seat by the biasing force of the torsion spring 117 set on the rear anchor bracket 114.

[0067] (Mechanism of action and effect) As described above, the power transmission unit PW2 according to the second embodiment converts the rotational force of the seat back 14 into a pulling force toward the rear of the seat via the first bracket 116, the second bracket 118, and the link arm 120, and transmits it to the buckle device 110. As a result, similar to the first embodiment, the power transmission unit PW2 can pull the buckle device 110 toward the rear of the seat in conjunction with the rotation of the seat back 14 toward the front of the seat. This makes it possible to reduce the protrusion of the buckle device 110 toward the front of the seat when the seat configuration of the vehicle seat 100 is in a double-folding state.

[0068] Furthermore, in the power transmission section PW2, when the buckle body 54 is pulled towards the rear of the seat, the second bracket 118 slides along the first guide hole 122 and the second guide hole 124 of the first bracket 116. As a result, the overall length L1 (see Figure 7) of the buckle device 110, including the webbing 52, is shortened in the front-rear direction of the seat, making it possible to miniaturize the buckle device 110.

[0069] <Third Embodiment> The vehicle seat 200 according to the third embodiment will be described below with reference to Figures 8 to 10. Note that components identical to those in the first or second embodiment described above will be given the same numbers and their descriptions will be omitted. In this third embodiment, the buckle device 110 is pulled towards the rear of the seat and tilted forward in conjunction with the rotation of the seat cushion 12 by the power transmission unit PW3 set in the buckle device 210.

[0070] As shown in Figure 8, the buckle device 210 comprises a buckle body 54 connected to the vehicle body via a long strip-shaped webbing 52, and a buckle boot 112 attached to the buckle body 54. The buckle body 54 and the webbing 52 have the same configuration as in the first embodiment described above. The buckle boot 112 has the same configuration as in the second embodiment described above, so a detailed explanation is omitted. One end of the webbing 52 is connected to the buckle body 54, and the other end of the webbing 52 is fixed to the floor of the vehicle body (not shown) via a rear anchor bracket 114.

[0071] The power transmission unit PW3 includes a first bracket 116 supported by the rear anchor bracket 114, a second bracket 118 connecting the first bracket and the webbing 52, and a cable 58 connecting the first bracket 116, the second bracket 118, and the cushion rotation support unit 20. The first bracket 116 and the second bracket 118 have the same configuration as in the second embodiment described above, so a detailed explanation will be omitted, but the second bracket 118 is supported so as to be slidable with respect to the first bracket 116 in approximately the front-rear direction of the seat.

[0072] The cable 58 has one end in its extending direction connected to a cushion rotation support section 20 that supports the front end of the seat cushion 12. The cushion rotation support section 20 includes a front anchor bracket 22 fixed to the floor of the vehicle body, a guide bracket 24 supported by the front anchor bracket 22, and a cushion rotation link 28 supported by the guide bracket 24 so as to be rotatable around a first rotation axis 26. The configurations of the front anchor bracket 22, the guide bracket 24, and the cushion rotation link 28 are the same as in the first embodiment described above, so the following will describe the components that differ from the first embodiment.

[0073] The cushion rotation link 28 has a cable attachment pin 220 that protrudes outward in the seat width direction from the front end in the seat longitudinal direction. The cable attachment pin 220 is located at a different position from the first rotation axis 26 at the front end of the cushion rotation link 28 and moves forward in conjunction with the rotation of the seat cushion 12 toward the front of the seat.

[0074] The cable 58 is guided towards the rear of the seat via the front cable support bracket 230, with one end in the direction of extension attached to the cable mounting pin 220. The front cable support bracket 230 is fixed to the floor of the vehicle body (not shown) by fastening it together with the front anchor bracket 22.

[0075] The cable 58 is guided toward the rear of the seat, and then its intermediate portion in the direction of extension is folded back and guided toward the front of the seat. The intermediate portion in the direction of extension is folded back by, for example, a folding anchor bracket 240 fixed to the floor of the vehicle body. The other end of the cable 58, which has been folded back via the folding anchor bracket 240, is then guided toward the front of the seat by a rear cable support bracket 250, and then attached to a first slide shaft 132 protruding from the second bracket 118. The rear cable support bracket 250 is fixed to the floor of the vehicle body by being fastened together with the rear anchor bracket 46, for example.

[0076] With this configuration, when the seat cushion 12 rotates toward the front of the seat, the cable mounting pin 220 provided on the cushion rotation link 28 moves toward the front of the seat, and one end of the cable 58 is pulled. As a result, a pulling force toward the rear and downward of the seat acts on the other end of the cable 58, which is connected to the second bracket 118 via the first slide shaft 132, and the webbing 52 and buckle body 54 are pulled toward the rear and downward of the seat as the second bracket 118 slides. In addition, the first bracket 116 rotates around the support shaft 115 of the rear anchor bracket 46 due to the pulling force transmitted from the second bracket 118 and is tilted forward toward the front of the seat. In this state, the torsion spring 117 set on the rear anchor bracket 46 biases the first bracket 116 toward the upward of the seat.

[0077] (Mechanism of action and effect) As explained above, the power transmission unit PW3 according to the third embodiment basically follows the configuration of the second embodiment, and therefore can achieve similar effects.

[0078] Furthermore, in the third embodiment, when the vehicle seat 200 is placed in a double-folding position, the buckle device 210 can be tilted forward by setting the seat cushion 12 to the flipped-up position. That is, the power transmission unit PW3 is configured to pull the buckle device 210 towards the rear of the seat in conjunction with the rotation of the seat cushion 12. Therefore, the buckle device 210 can be moved to the storage position in advance before the subsequent operation of tilting the seat back 14 forward.

[0079] [supplementary explanation] In the second and third embodiments described above, the other end of the webbing 52 is connected to the rear anchor bracket 46, but the present invention is not limited to this. For example, the other end of the webbing 52 may be connected to the front end of the second bracket 118.

[0080] Furthermore, in each of the above embodiments, the power transmission unit includes a first transmission member connected to the vehicle body via a bracket, and a second transmission member connecting the first transmission member and the buckle body on the front and rear sides of the seat of the first transmission member. The first transmission member supports the second transmission member so as to be slidable in the front-rear direction of the seat, and in conjunction with the rotation of the seat cushion or seat back, the relative position of the second transmission member is displaced toward the rear of the seat relative to the first transmission member, thereby shortening the overall length of the seat back device including the webbing. However, the present invention is not limited thereto. In the present invention, shortening the overall length of the buckle device is not essential, and the entire buckle device including the webbing may be configured to slide toward the rear of the seat in conjunction with the rotation of the seat cushion or seat back.

[0081] In the first embodiment, the boot case 70 corresponds to the first transmission member, and the buckle boot 60 corresponds to the second transmission member. In the second and third embodiments, the first bracket 116 corresponds to the first transmission member, and the second bracket 118 corresponds to the second transmission member.

[0082] Furthermore, the configurations of each embodiment can be combined as appropriate. [Explanation of symbols]

[0083] 10 Vehicle seats 12 seat cushions 14 Seatback 26. First axis of rotation (axis of rotation) 44. Second axis of rotation (axis of rotation) 50 Buckle device 52 Webbing 100 Vehicle Seats 110 Buckle device 200 Vehicle Seats 210 Buckle device PW1 Power transmission section PW2 Power transmission section PW3 Power transmission section

Claims

1. A seat cushion having a seating surface, The aforementioned seat cushion is positioned on the rear end side of the seat and has a seat back with a backrest surface, A buckle device is positioned on one side of the seat cushion in the seat width direction and connected to the vehicle body via webbing, At least one rotating shaft supports at least one of the seat cushion and the seat back so as to be rotatable around an axis in the seat width direction, The system includes a power transmission unit that converts the rotational force around the rotation axis into a tensile force toward the rear of the seat and transmits it to the buckle device, The power transmission unit is a vehicle seat that, in conjunction with the rotation of the seat cushion or the seat back, pulls the buckle device towards the rear of the seat.

2. The vehicle seat according to claim 1, wherein the power transmission unit shortens the overall length of the buckle device, including the webbing, when the buckle device is pulled towards the rear of the seat.

3. The vehicle seat according to claim 1 or 2, wherein the power transmission unit rotates the buckle device around an axis in the tongue insertion direction and pulls it toward the rear of the seat.

4. The rotating shaft includes a first rotating shaft that supports the seat cushion so as to be rotatable around an axis in the seat width direction, and a second rotating shaft that supports the seat back so as to be rotatable around an axis in the seat width direction. The seat cushion is configured to rotate around the first pivot axis so that it can be set to a seating position that supports the buttocks of an occupant seated on the seat cushion, and to a flipped-up position where the seating surface faces forward towards the seat. The seat back is configured to rotate around the second pivot axis so that it can be set to a backrest position that supports the back of an occupant seated on the seat cushion, and to a forward-tilting position where the backrest surface faces downward towards the seat. A vehicle seat according to claim 1 or claim 2.

Images