VEHICLE SEAT

BACKGEOUND OF THE INVENTION

1. Field of the Invention [OOOl] The invention relates to a seat for use in a vehicle, and more particularly to a vehicle seat that is placed in a folded position when a seat back is tilted forward while a seat cushion moves toward the front of the seat.

2. Description of the Related Art [0002] One example of vehicle seat of the above type is disclosed in

JP-A-2003-252097. In the example disclosed in this publication, a lower portion of the seat back is supported by a hinge bracket such that the seat back can pivot relative to a vehicle body, and a front portion of a seat cushion is supported by a first link such that the seat cushion can pivot relative to the vehicle body. The seat back and the rear portion of the seat cushion are connected to each other by a second link. When the seat back is forwardly tilted toward the top face of the seat cushion, the first link and the second link pivot toward the front of the seat, and the seat cushion moves onto the floor of the vehicle body ahead of the seat while the seat back is folded, so that the back side of the seat back provides a horizontal platform or floor that extends continuously from the rear deck.

[0003] In the example as disclosed in JP-A'2003-252097, however, it is necessary to increase the amount of forward movement of the seat cushion or shorten the longitudinal dimension of the seat cushion, in order to form a continuous flat surface on the forwardly tilted seat back and the seat cushion that adjoins the seat back in the longitudinal direction of the vehicle. It is also desirable that the vehicle seat of the above type requires only a simple procedure or operation for placing the seat in the folded position.

CONFIRMATION COPY

SUMMARY OF THE INVENTION

[0004] It is an object of the invention to provide a vehicle seat which achieves a reduction of the amount of movement of a seat cushion toward the front of the seat while assuring sufficient dimensions or size of the seat cushion, and which requires only a simple procedure or operation for placing the seat in the folded position.

[0005] One aspect of the invention provides a vehicle seat that includes: (a) a seat cushion that is supported by a support member mounted on a vehicle floor such that the seat cushion is movable toward the front of the seat, (b) a seat back to which a link member that is pivotally coupled at one end to the vehicle floor is pivotally coupled at the other end, and which is selectively placed in a standing position, and a forwardly tilted position to which the seat back is tilted toward the front of the seat while the link member pivots toward the rear of the seat about a joint of the link member with the vehicle floor, and (c) an interlocking mechanism operable to move the seat cushion toward the front of the seat in response to forward tilting of the seat back, wherein the seat back placed in the forwardly tilted position and the seat cushion moved toward the front of the seat upon forward tilting of the seat back are located adjacent to each other.

[0006] In the vehicle seat according to the above aspect of the invention, the link member that is pivotally coupled at one end to the vehicle floor is pivotally coupled at the other end to the seat back, and the seat back is arranged to be tilted forward, i.e., toward the front of the seat, while the link member pivots toward the rear of the seat about a joint of the link member with the vehicle floor. Namely, the seat back is tilted forward with its pivot or center of tilting (i.e., a joint of the seat back with the link member) moving toward the rear of the seat due to the pivotal movement of the link member toward the rear of the seat. Accordingly, it is not necessary to increase the amount of forward movement of the seat cushion or shorten the longitudinal dimension of the seat cushion in order to provide a continuous surface on the forwardly tilted seat back and the seat cushion located

adjacent to the seat back. It is thus possible to reduce the amount of movement of the seat cushion toward the front of the seat while assuring sufficiently large dimensions or size of the seat cushion.

[0007] Furthermore, in the vehicle seat according to the above aspect of the invention, the interlocking mechanism is actuated to move the seat cushion toward the front of the seat in response to the forward tilting of the seat back. To place the vehicle seat in the folded position, therefore, it is only required to tilt the seat back forward, and there is no need to operate both the seat back and the seat cushion. Thus, the vehicle seat of the above aspect of the invention is advantageous in enhanced ease of operation for placing the seat in the folded position.

[0008] In the vehicle seat according to the above aspect of the invention, the interlocking mechanism may include a biasing member that biases the seat cushion toward the front of the seat, a pulley that is disposed rearward of a joint of the link member with the vehicle floor, and a connecting wire that is passed around the pulley and is connected to the seat cushion and the link member.

[0009] In the vehicle seat as described above, the seat cushion is biased or urged toward the front of the seat by the biasing member. Also, the connecting wire that is passed around the pulley is connected to the seat cushion and the link member. With this arrangement, when the vehicle seat is in a seating position for supporting an occupant thereon, namely, when the seat back is in the standing position and the link member is in the forwardly pivoted position, the pulling force of the connecting wire connected to the link member is transmitted to the seat cushion via the pulley, and the seat cushion is placed in the rear or retracted position against the bias force of the biasing member. When the seat back is forwardly tilted toward the front of the seat from this condition, the connecting wire is loosened due to pivotal movement of the link member, and the pulling force of the connecting wire is reduced. As a result, the seat back is moved toward the front of the seat under the bias force of the biasing member, and the vehicle seat is

placed in the folded position.

[OOIO] When the seat back is rotated toward the rear of the seat, i.e., is rotated back to the standing position, from the above condition in which the vehicle seat is in the folded position, the connecting wire is pulled due to pivotal movement of the link member, so as to move the seat cushion toward the rear of the seat (i.e., to the retracted position), whereby the vehicle seat is placed in the seating position.

Thus, the seat cushion can move back and forth in response to the tilting or rotation of the seat back, which makes it easy to switch the vehicle seat between the folded position and the seating position. [0011] The vehicle seat according to the above aspect of the invention may further include an expandable board adapted to be unfolded on the continuous surface formed on the seat cushion and the seat back.

[0012] In the vehicle seat as described just above, when the vehicle seat is placed in the folded position with the seat back tilted forward, the expandable board can be unfolded on the continuous surface formed on the seat cushion and the seat back. It is thus possible to provide flat, stable cargo space in the vehicle. [0013] In the vehicle seat according to the above aspect of the invention, the interlocking mechanism may include a fixing mechanism that fixes the seat back in the standing position, and an operating portion of the fixing mechanism may be provided in a cargo room of the vehicle. In this case, the interlocking mechanism can be easily operated or manipulated from the cargo room.

[00141 As described above in detail, the vehicle seat according to the above aspect of the invention achieves a reduction of the amount of movement of the seat cushion toward the front of the seat while assuring sufficiently large dimensions or size of the seat cushion, and requires only a simple procedure or operation for placing the vehicle seat in the folded position.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The foregoing and further objects, features and advantages of the invention will become apparent from the following description of a preferred embodiment with reference to the accompanying drawings, wherein like numerals are used to represent like elements and wherein^ FIG. 1 is a side view showing the whole construction of a vehicle seat according to one embodiment of the invention;

FIG. 2 is a view useful for explaining the operation of the vehicle seat according to the embodiment of the invention;

FIG. 3 is a view useful for explaining the operation of the vehicle seat according to the embodiment of the invention;

FIG. 4 is a view useful for explaining the operation of the vehicle seat according to the embodiment of the invention; and

FIG. 5 is a bottom view of the vehicle seat according to the embodiment of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0016] Referring to FIG. 1 through FIG. 5, the construction of a seat 10 for a vehicle according to one embodiment of the invention will be described in detail.

[0017] FIG. 1 through FIG. 5 illustrate the vehicle seat 10 constructed according to the embodiment of the invention. In these figures, arrow Fr indicates the frontward direction as one of the longitudinally opposite directions of the vehicle, and arrow Up indicates the upward direction as one of the vertically opposite directions of the vehicle, while arrow Out indicates the outward direction as one of the laterally opposite directions parallel to the width of the vehicle. [0018] The vehicle seat 10 according to the embodiment of the invention is favorably used as, for example, a rear seat disposed adjacent to a cargo room 72 of the vehicle, as shown in FIG. 1. The vehicle seat 10 includes a seat cushion 12 and a seat back 14, as shown in each of the figures.

[0019] A third link member 16 is pivotally coupled at one end thereof to a

front portion of the seat cushion 12, and is pivotally coupled at the other end to a front portion of a frame member 18 mounted integrally on a floor 70 of the vehicle body. A pin 20 that projects outward in the direction of the width of the vehicle is provided at a rear portion of the seat cushion 12, and a guide member 22 is provided on the frame member 18 to be located at one side of the seat cushion 12. The guide member 22 is formed with a guide hole 24 that extends in the longitudinal direction of the vehicle, and the above-mentioned pin 20 provided on the seat cushion 12 is received in the guide hole 24 and is supported by the guide member 22 such that the pin 20 is movable in the longitudinal direction of the vehicle.

[0020] A lock lever 26, which is pivotally provided on the guide member 22, is formed with an engaging portion 28 that can be engaged with the pin 20. As shown in FIG. 1, the lock lever 26 is constantly biased in the direction of Rl by a spring 30 mounted on the frame member 18, and is also connected via a wire 34 to a lock release mechanism 32 mounted on the frame member 18.

[0021] The lock release mechanism 32 includes a lock release lever 32A. When the lock release lever 32A is pulled, the wire 34 is drawn toward the lever 32A so that the lock lever 26 pivots in the direction of R2 in FIG. 1. The lock release mechanism 32 is mounted to a rear portion of the frame member 18, such that the lock release lever 32A can be reached or accessed from the cargo room 72 (for example, from an opening of a back door that is not illustrated).

[0022] In the meantime, a first link member 36 and a second link member 38 are pivotally coupled at one end thereof to a lower portion of the seat back 14. The first link member 36 and the second link member 38 are also pivotally coupled at the other end thereof to a central portion and a rear portion, respectively, of the frame member 18 mounted integrally on the vehicle floor 70.

[0023] As shown in FIG. 1 through FIG. 3, when the seat back 14 is tilted forward, the first link member 36 and the second link member 38 pivot toward the rear of the seat (i.e., in the directions of R3 and R4, respectively). Since the first

link member 36 and second link member 38 pivot toward the rear of the seat, the seat back 14 tilts forward with its pivots (i.e., joints between the seat back 14 and the first and second link members 36, 38) being moved toward the rear of the seat. [0024] The vehicle seat 10 of the present embodiment is arranged to be placed in a folded position as shown in FIG. 3, when the seat back 14 is tilted forward as described above, and at the same time the seat cushion 12 is moved toward the front of the seat. In the folded position, the seat back 14 and the seat cushion 12 adjoins each other in the longitudinal direction of the vehicle to thus form a continuous flat surface 40 thereon. [0025] Also, in the vehicle seat 10 of the present invention, an expandable board 42 is provided at the back face of the seat back 14. The expandable board 42 consists of two plates 42A, 42B. One of the plates 42A is fixed to the back face of the seat back 14, and the other plate 42B is joined to the plate 42A via a joint portion 44. The two plates 42 A, 42B have substantially the same configuration, and the expandable board 42 can be folded on the back face of the seat back 14, as shown in FIG. 1 through FIG. 3. When the seat back 14 and the seat cushion 12 are located adjacent to each other in the longitudinal direction to form the continuous flat surface 40, the expandable board 42 may be unfolded on the flat surface 40, as shown in FIG. 4. [0026] The vehicle seat 10 of the present embodiment is provided with an interlocking mechanism for moving the seat cushion 12 toward the front of the seat in response to the forward tilting of the seat back 14 when the seat 10 is placed in the folded position, as described above. The construction of the interlocking mechanism will be described in greater detail. As shown in FIG. 5, a bracket 46 is fixed to the underside or back of the seat cushion 12, and a sliding wire 48 is coupled at one end to the bracket 46. The direction of extension of the sliding wire 48 is changed by a pulley 50 fixed to the frame member 18, and the sliding wire 48 is coupled at the other end thereof to one end of a tension spring 52 whose other end is fixed to the frame member 18. With this arrangement, the force of the

tension spring 52 for pulling the seat cushion 12 toward the front of the seat is constantly applied to the seat cushion 12.

[0027] On the other hand, a pulley 54 is disposed at the frame member 18, to be located rearward of a joint between the frame member 18 and the second link member 38, as shown in FIG. 1 and FIG. 5. Also, a connecting wire 56 is fixed at one end to a longitudinally intermediate portion of the second link member 38, as shown in FIG. 1. The connecting wire 56 is passed around the pulley 54 so that the direction of extension of the wire 56 is changed from the rearward direction to the frontward direction of the seat. The connecting wire 56 is then guided to below the seat and coupled at the other end to the above-mentioned bracket 46. With this arrangement, when the second link member 38 pivots toward the front of the seat, force is applied from the connecting wire 56 to the seat cushion 12 so as to pull the seat cushion 12 toward the rear of the seat.

[0028] In addition, a tension wire 58 is joined or secured at one end to an intermediate portion of the connecting wire 56 by a securing device 60. The direction of extension of the tension wire 58 is changed at the above-mentioned pulley 50, and the tension wire 58 is coupled at the other end to one end of a tension spring 62 whose other end is fixed to the frame member 18. This arrangement prevents loosening of the connecting wire 56. [0029] Next, the operation of the vehicle seat 10 according to the embodiment of the invention will be described.

[0030] (Switching from Seat Mode to Cargo Mode) As shown in FIG. 1, when the vehicle seat 10 is in a seat mode, namely, is placed in a seating position for supporting an occupant thereon, the following operation is performed so as to switch the vehicle seat 10 to a cargo mode for making the cargo room 72 larger. Initially, the lock release lever 32A of the lock release mechanism 32 is pulled, so that the lock lever 26 is pulled by the wire 34 and thus pivots in the direction of R2 in FIG. 1. As a result, the pin 20 is released from the engaging portion 28 of the lock lever 26.

[0031] From this condition, the seat back 14 is tilted forward, as shown in FIG. 2. As a result, the second link member 38 pivots toward the rear of the seat (i.e., in the direction of R4 in FIG. 2), resulting in loosening of the connecting wire 56, and the pulling force of the connecting wire 56 applied to the seat cushion 12 is reduced. Then, the seat cushion 12 moves toward the front of the seat under the bias force of the tension spring 52. As the seat cushion 12 moves toward the front of the seat, the third link member 16 pivots toward the front of the seat (i.e., in the direction of R5 in FIG. 2). During the forward movement of the seat cushion 12, the pin 20 moves along the guide hole 24, so that the rear portion of the seat cushion 12 remains supported by the guide member 22.

[0032] In the vehicle seat 10 of the present embodiment, the seat cushion 12 moves toward the' front of the seat in response to the forward tilting or rotation of the seat back 14, in the manner as described above. At this time, the seat back 14 is tilted toward the front of the seat, with the first link member 36 and second link member 38 pivoting toward the rear of the seat (i.e., in the directions of R3 and R4 in FIG. 2) about their joints on the side of the vehicle floor 70. Namely, as the first link member 36 and the second link member 38 pivot toward the rear of the seat (i.e., in the directions of R3 and R4), the seat back 14 is tilted forward with its pivots (i.e., joints of the seat back 14 with the first and second link members 36, 38) moving toward the rear of the seat.

[0033] From the condition as shown in FIG. 2, the seat back 14 is further tilted forward, until the vehicle seat 10 is placed in the folded position in which the seat back 14 and the seat cushion 12 adjoin each other in the longitudinal direction of the vehicle, as shown in FIG. 3. In this position, the seat back 14 and the seat cushion 12, which are located adjacent to each other in the longitudinal direction, cooperate with each other to form the continuous flat surface 40.

[0034] Subsequently, the expandable board 42 is unfolded on the continuous flat surface 40 formed on the seat back 14 and seat cushion 12 located adjacent to each other in the longitudinal direction, as shown in FIG. 4. In this

manner, the vehicle seat 10 is switched to the cargo mode in which the cargo room 72 is expanded, and flat, stable cargo space is formed in the vehicle.

[0035] (Switching from Cargo Mode to Seat Mode) When the vehicle seat 10 is in the cargo mode as described above, the following operation is performed so as to switch the vehicle seat 10 to the seat mode, namely, place the seat 10 in the seating position for supporting an occupant thereon. Initially, the expandable board 42 is folded onto the back face of the seat back 14, as shown in FIG. 3. From this condition, the seat back 14 is rotated toward the rear of the seat, as shown in FIG. 2. With the seat back 14 thus pivoting toward the rear of the seat, the connecting wire 56 is pulled in response to pivotal movement of the second link member 38 toward the front of the seat (in the direction of R6 in FIG. 2), so that the seat cushion 12 moves toward the rear of the seat.

[0036] At this time, loosening of the connecting wire 56 is prevented since the force of the tension spring 62 for pulling the connecting wire 56 is applied to the connecting wire 56 via the tension wire 58. Accordingly, the seat cushion 12 moves smoothly toward the rear of the seat in response to the rearward pivotal movement of the seat back 14.

[0037] When the seat back 14 is lifted up to the standing position as shown in FIG. 1, the seat cushion 12 moves rearward to the most retracted position, and the pin 20 is brought into engagement with the engaging portion 28 of the lock lever 26. Thus, in the vehicle seat 10 of the present embodiment, it is possible to move the seat cushion 12 toward the rear of the seat and hold the same in the original position (i.e., the most retracted position), simply by rotating the seat back 14 toward the rear of the seat and placing the same in the standing position. In this manner, the vehicle seat 10 is switched to the seat mode, allowing an occupant to be seated on the seat 10.

[0038] In the above aspect of the invention, the connecting wire 56 is fixed at one end to longitudinally intermediate portion of the second link member 38. The connecting wire 56 may be fixed at one end to an upward portion of the first

link member 36. In this case, the force is applied from connecting wire 56 to the seat cushion 12 in response to the pivotal movements of the first link member 36.

[0039] Next, the operation and effects of the vehicle seat 10 according to the embodiment of the invention will be explained. [0040] As described above in detail, in the vehicle seat 10 of the present embodiment, as the first link member 36 and the second link member 38 pivot toward the rear of the seat (i.e., in the directions of R3 and R4, respectively), the seat back 14 is tilted forward with its pivots (i.e., joints of the seat back 14 with the first and second link members 36, 38) moving toward the rear of the seat. Accordingly, it is unnecessary to increase the amount of forward movement of the seat cushion 12 or shorten the longitudinal dimension of the seat cushion 12 in order to provide a continuous surface on the forwardly tilted seat back 14 and the seat cushion 12 that adjoins the seat back 14. It is thus possible to reduce the amount of movement of the seat cushion 12 toward the front of the seat while at the same time assuring sufficiently large dimensions or size of the seat cushion 12.

[0041] Furthermore, in the vehicle seat 10 of this embodiment, the seat cushion 12 is moved toward the front of the seat in response to the forward tilting of the seat back 14, as described above. Accordingly, the vehicle seat 10 can be placed in the folded position simply by tilting the seat back 14 forward, thus eliminating a need to operate both of the seat ,back 14 and the seat cushion 12. Thus, the vehicle seat 10 of this embodiment is advantageous in enhanced ease of operation for placing the seat 10 in the folded position.

[0042] Also, in the vehicle seat 10 of the present embodiment, the seat back 14 can be moved back and forth along with the pivotal movement of the seat back 14, as described above. Thus, the seat 10 can be easily switched between the folded position and the seating position for supporting the occupant thereon.

[0043] Also, in the vehicle seat 10 of the present embodiment, the lock release mechanism 32 for bringing the seat 10 into the folded position is located in the rear portion of the frame member 18, such that the lock release mechanism 32

(more particularly, the lock release lever 32A) can be reached from the cargo room 72 (for example, from the opening of the back door that is not illustrated), as described above. Thus, the lock release mechanism 32 can be easily operated or manipulated from the cargo room 72 side. [0044] Furthermore, when the vehicle seat 10 of this embodiment is placed in the folded position with the seat back 14 tilted forward, the expandable board 42 can be unfolded on the continuous flat surface 40 formed on the seat cushion 12 and the seat back 14. In this manner, flat and stable cargo space can be surely provided in the vehicle. [0045] Also, in the vehicle seat 10 of the present embodiment, the seat cushion 12 and the seat back 14 can be arranged in the longitudinal direction of the vehicle to provide a flat platform. Thus, the seat 10, when placed in the folded position, does not obstruct the view from a side winάow(s) as is the case with a vehicle seat of a type that flips up toward a side window(s) when folded. It is also possible to minimize the loading height or level, thus making it easy to load the expanded cargo room 72 including the seat 10 in the folded or flat position.

[0046] Since the seat cushion 12 and the seat back 14 can be arranged in the longitudinal direction to provide a flat platform while assuring sufficiently large dimensions or size of the seat cushion 12, as described above, the vehicle seat 10 of this embodiment assures improved passenger comfort and expanded cargo space at the same time.