Vehicle seat

In order to prevent distortion of slide rails caused by an urging force generated by an urging member in a vehicle tumble seat, a vehicle seat is capable of taking a stowed position in which a seat back 6L is folded onto a seat cushion 5L and the seat cushion 5L together with the folded seat back 6L is rotatably lifted away from a floor 3, and the vehicle seat is configured to include: a support member 31 coupled to the floor; a rotating member 33L rotatably supported by the support member via a support shaft extending in a right-left direction; a lower rail 41 extending in a front-rear direction and coupled at an end to the rotating member so as to be extend literally offset relative to the support shaft; an upper rail 42 slidably supported by the lower rail and coupled to the seat cushion; a coupling device 51 provided at a second end of the lower rail on a side toward the support shaft and capable of selectably connecting to the floor; and an urging device 60 extending the front-rear direction and having one end coupled to the support member and a second end coupled to the lower rail on the side toward the support shaft side, wherein the urging device is configured to be expandable and contractible in a longitudinal direction thereof so as to urge the seat cushion in such a direction as to rotate about the support shaft away from the floor.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is the U.S. National Stage entry of International Application Number PCT/JP2017/013554 filed under the Patent Cooperation Treaty having a filing date of Mar. 31, 2017, which claims priority to Japanese Patent Application No. 2016-153141 having a filing date of Aug. 3, 2016, which are incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a vehicle seat adapted to be mounted on a vehicle such as an automobile.

BACKGROUND ART

Known motor vehicle seats include a tumble seat, which is typically used in a second or third row of seat(s) and configured to pivot frontward, together with a seat back folded onto the seat, about an axis in a front portion thereof to take an upright stowed position. Some known tumble seats are provided with a spring (or gas damper) between a floor and a seat cushion so as to urge rotation of the seat to thereby facilitate a tuck-away operation; that is, a frontward rotation of the seat cushion (See Patent Document 1).

PRIOR ART DOCUMENT(S)

SUMMARY OF THE INVENTION

Task to be Accomplished by the Invention

However, when a gas spring is provided between a floor and a seat cushion of a tumble seat, an urging force always act on part of the seat cushion side, and thus a gas spring provided at an improper location can distort a seat cushion frame or other parts of the seat cushion. In particular, in cases where a seat cushion of a tumble seat is provided with slide rails which allow the seat cushion to horizontally move with regard to a floor and also provided with a gas spring, when an urging force generated by the gas spring acts on the slide rails, the urging force generated by the gas spring can distort the slide rails, thereby inhibiting the smooth movement of the slide rails.

The present invention has been made in view of such problems of the prior art, and a primary object of the present invention is to provide a vehicle tumble seat configured to prevent distortion of slide rails caused by an urging force generated by an urging member.

Means to Accomplish the Task

In order to attain the above object, an aspect of the present invention provides a vehicle seat capable of taking a stowed position in which a seat back (6L) is folded onto a seat cushion (5L) and the seat cushion (5L) together with the folded seat back (6L) is rotatably lifted away from a floor (3), the vehicle seat including: a support member (31) coupled to the floor; a rotating member (33L) rotatably supported by the support member via a support shaft extending in a right-left direction; a lower rail (41) extending in a front-rear direction and coupled at an end to the rotating member so as to be extend literally offset relative to the support shaft; an upper rail (42) slidably supported by the lower rail and coupled to the seat cushion; a coupling device (51) provided at a second end of the lower rail on a side toward the support shaft and capable of selectably connecting to the floor; and an urging device (60) extending the front-rear direction and having one end coupled to the support member and a second end coupled to the lower rail on the side toward the support shaft side, wherein the urging device is configured to be expandable and contractible in a longitudinal direction thereof so as to urge the seat cushion in such a direction as to rotate about the support shaft away from the floor.

In this configuration, the support shafts and the coupling devices, which are secured to the floor, are disposed both frontward and rearward of the urging device which generates an urging force in the front-rear direction. Thus this configuration restricts the expansion of the urging device, thereby suppressing the deformation of the lower rail and the seat cushion to which the urging device is coupled. As a result, the upper rail is allowed to smoothly move relative to the lower rail.

In the above-described aspect, the support shaft, the urging device, and the coupling device are arranged on an imaginary straight line extending in the front-rear direction.

In this configuration, the urging force generated by the urging device is more securely transmitted to the coupling device, resulting in that the deformation of the lower rail is suppressed.

In the above-described aspect, it is preferable that the second end of the lower rail is coupled to a reinforcing member (48), and that the coupling device and the second end of the urging device are coupled to the reinforcing member.

In this configuration, the urging force generated by the urging device is transmitted to the coupling device via the reinforcing member, resulting in that the deformation of the lower rail is suppressed.

In the above-described aspect, it is preferable that the coupling device includes a latch (51C) configured to be engageable with a striker (52) provided on the floor, and that the latch is rotatable about an axis line extending in the right-left direction and is arranged such that the latch, viewed from the right-left direction, has an upper part which overlaps the lower rail and a lower part which protrudes downward beyond the lower rail.

In this configuration, the distance between the lower rail and the floor is smaller. Thus, a smaller dead space is created between the seat cushion and the floor.

In the above-described aspect, the support shaft, the coupling device, and the urging device are preferably disposed within an inner region of the vehicle seat in the right-left direction.

In this configuration, the urging device is arranged on a center portion of the left seat in the right-left direction. Thus, this configuration reduces a difference between the loads applied on the right and left halves of the seat cushion, thereby suppressing the deformation of the seat cushion. Since the support shaft, the coupling device, and the urging device are disposed within an inner region of the vehicle seat, the support shaft, the coupling device, and the urging device are hardly visible from the outside and a user is prevented from unintentionally touching the urging device.

In the above-described aspect, it is preferable that the rotating member includes a front end portion rotatably supported by the support shaft and a rear end portion offset outward relative to the front end portion in the right-left direction of the vehicle seat, and that a front end portion of the lower rail is coupled to the rear end portion of the rotating member.

In this configuration, the support shaft and the lower rail are positionally offset relative to each other by the rotating member.

In the above-described aspect, it is preferable that the lower rail is coupled to the rotating member at a front end, that a rail locking device (43) is provided between the upper rail and the lower rail and configured to selectively hold a position of the upper rail with respect to the lower rail, that a rail urging member (56) is provided and configured to urge the seat cushion frontward relative to the lower rail, and that the rail locking device is coupled to the seat back via a power transmission member (45), and configured such that, when the seat back is folded toward the seat cushion at an angle within a prescribed angular range, the rail locking device is driven by the power transmission member to enable the upper rail to move with respect to the lower rail.

In this configuration, when the seat back is folded onto the seat cushion, the seat cushion moves to the front end position with respect to the lower rail, thereby enlarging a space rearward of the seat.

In the above-described aspect, it is preferable that the coupling device includes: a latch (51C) configured to be engageable with a striker (52) provided on the floor; an operating input part (55) configured such that a user's operating force is input to the operating input part; a connecting mechanism (54) configured to selectively transmit the operating force from the operating input part to the latch; and a slide position detecting device (62) provided between the seat cushion and the lower rail and configured to operate when the seat cushion is at a prescribed front end position relative to the lower rail, and that, when the seat cushion is at the front end position, the connecting mechanism is driven by the slide position detecting device to transmit the operating force from the operating input part to the latch.

In this configuration, the coupling device is allowed to be unlocked only when the seat cushion5L is at the front end position with respect to the lower rail. Thus, the vehicle seat is allowed to move to the stowed position with the seat cushion at the front end position with respect to the lower rail and the enlarged space created rearward of the seat.

Effect of the Invention

In the above-described configurations, a vehicle tumble seat can be configured to prevent distortion of slide rails caused by an urging force generated by an urging member.

DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

A vehicle rear seat (for e.g. a second row or third row of seat(s)) according to one embodiment of the present invention will be described with reference to the drawings. In the following description, the directions of right and left are defined as those for an occupant seated on the seat. In the right-left direction, an “inner side” refers to a side on which the center of the seat is located, and an “outer side” refers to a side away from the center of the seat. A pair of same parts or features provided on either of the right and left sides are designated by the same reference numeral and the description of each part or feature will not be repeated. As will be described later, a seat is movable between a usable position (seating position) and an upright stowed position and has different forms and orientations in the respective positions. However, description will be made with reference to a seat in the usable position unless otherwise specified.

As shown inFIG. 1, a row of rear seats of an automobile includes a left seat1on the left, and a right seat2used as a rightmost seat and a center seat. The seats1and2include seat cushions5L,5R rotatably provided on a floor3of the automobile and seat backs6L,6R rotatably supported by the seat cushions5L,5R, respectively. The seat cushions5L,5R have respective seat cushion frames7L,7R, and the seat backs6L,6R have respective seat back frames8L,8R, all the frames forming the shapes of respective cushions and seat backs. The seat cushions5L,5R and the seat back6L,6R, the seat cushion frames7L.7R and the seat back frames8L,8R support respective pads, each pad being covered with a skin material.

The seat cushion frame7L of the left seat1includes a pair of right and left cushion side frames14extending in the front-to-rear direction, a front member15crossing and connecting respective front end portions of the cushion side frames14, a rear member16crossing and connecting respective rear end portions of the cushion side frames14, an intermediate member17crossing and connecting respective intermediate portions between the respective front and rear end portions of the cushion side frames14, and a plate-shaped cushion pan frame18crossing and hanging between respective intermediate portions of the intermediate member17and the rear member16, where the intermediate portions are located between the respective right and left ends of the intermediate member17and the rear member16. The respective rear end portions of the cushion side frame14protrude upward to form a seat back support14A. For example, each of the cushion side frames14and the cushion pan frame18is formed of a steel-metal member. The front member15, the rear member16, and the intermediate member17may be formed of metal pipes.

The seat back6L of the left seat1includes a pair of right and left rear side frames21extending vertically, an upper member22crossing and connecting the respective upper end portions of the backside frames21, a lower member23crossing and connecting the respective lower end portions of the backside frames21, and a plate-shaped back pan frame24, plate-shaped back pan frame24covering a frame-shaped rear portion formed by the right and left backside frames21, the upper member22, and the lower member23. The respective lower end portions of the right and left backside frames21are rotatably supported by the right and left seat back supports14A via respective reclining mechanisms26. The reclining mechanism26may be any known reclining mechanism, which is used to lock the rotational position of the backside frame21to the cushion side frame14at any vertical position and also enables the backside frame21to rotate with respect to the cushion side frame14when a prescribed tensile load is applied to an operating input part of the reclining mechanism26. The operating input part of each right and left reclining mechanisms26is connected to a reclining operating lever (not shown) via a first control cable (not shown). The control cable as a power transmission member may be any publicly known cable having a cylindrical outer case and an inner cable movably extending through in the outer case. A user can operate the reclining operating lever to apply a tensile load to the operating input part of each of the right and left reclining mechanisms26via the first control cable, thereby enabling each reclining mechanism26to rotate. The reclining operating lever may be provided, for example, at the upper end of the left side backside frame21.

The seat cushion5L is rotatably supported by the floor3of an automobile body via a pair of right and left support members31coupled to the floor3, a pair of right and left rotating members33R,33L rotatably supported by the support members31via support shafts32extending in the right-left direction of the respective support members31, and a pair of right and left slide rails34coupled to respective rotating member33R,33L.

As shown inFIGS. 2 to 6, each support member31has upper and lower main faces and includes a bottom wall31A coupled to the upper surface of the floor3, and a pair of right and left support walls31B protruding upward from the bottom wall31A and having their respective right and left main faces. The bottom wall31A and the support walls31B are formed of one steel-metal member or multiple steel-metal members joined to one another. The right and left support walls31B may be connected to each other by bolts or reinforcing walls.

The support shaft32crosses and connects the two upper end portions of each support member31. The support shaft32is coupled to each support member31by thread connection, welding or other coupling methods.

The left rotating member33L is rotatably supported by the support shaft32at its front end portion. The rotating member33L extends rearward from the front end portion to form its rear end portion extending positionally offset to the left relative to the front end portion. The left rotating member33L has first, second, and third members37,3839which are steel-metal members joined together. The first member37includes an upper wall part37A extending in the front-rear direction, and right and left side wall parts37B protruding downward from right and left side edges of the upper wall part37A, and the first member37defines a groove portion that opens downward and extends in the front-rear direction. Front end portions of the right and left side wall parts37B of the first member37define respective bearing holes37C so as to extend through the respective side wall parts coaxially with each other. The support shaft32is inserted to pass through the bearing holes37C. The second member38includes a bottom wall part38A with an upper main face and a right side wall part38B protruding upward from and extending along the right side edge of the bottom wall part38A. The bottom wall part38A of the second member38includes its rear end portion extending positionally offset to the left (i.e. outwardly of the seat) relative to its front end portion. The right side wall part38B of the second member38includes its front end portion extending in the front-rear direction, its intermediate portion extending in a direction at an angle to the front-rear direction, and a rear end portion part extending in the front-rear direction positionally offset to the left relative to the front end portion. The first member37includes its rear end portion disposed above the right front portion of the second member38, and its front portion protrudes frontward from the second member38. A right side face of the side wall part37B on the right side of the first member37is in contact with a left side face of the right side wall part38B of the second member38. The third member39includes a lower wall part39A extending in the front-rear direction, and right and left side wall parts39B protruding upward from the right and left side edges of the lower wall part39A, and the third member39defines a groove portion that opens upward and extends in the front-rear direction. The third member39is arranged on an upper side face of a left rear portion of the bottom wall part38A of the second member38. The third member39is disposed to be positionally offset to the left relative to the first member37and the support shaft32, and is arranged so that its right front end portion overlaps the left rear part of the first member37as viewed from above. A left side face of the right side wall part39B of the third member39is in contact with the right side face of the left side wall part37B of the first member37. A right side face of the right side wall part39B of the third member39is in contact with a left side face of the rear end portion of the right side wall part38B of the second member38. The first, second, and third members37,38,39are coupled to each other by welding or other coupling methods at proper locations. The first, second, and third members37,38,39cooperatively form a closed cross section structure at a right front portion of the rotating member33L. Moreover, the third member39defines a groove portion that opens upward and extends in the front-rear direction at a rear left portion of the rotating member33L.

The rotating member33R on the right side, which extends in the front-rear direction, is formed in a groove shape opened upward and is rotatably supported by the support shaft32at the front end portion.

Each slide rail34includes a lower rail41extending in the front-rear direction, an upper rail42movably supported by the lower rail41to be movable in the front-rear direction, and a rail locking device43(seeFIG. 3) for selectively holding a position of the upper rail42with respect to the lower rail41. Each lower rail41includes a bottom wall part having upper and lower main faces and extends in the front-rear direction, right and left side wall parts protruding upward substantially at the right angle from the right and left side edges of the bottom wall part, and upper wall parts protruding inwardly substantially at the right angle from the upper edges of respective bottom wall parts. The upper rail42includes a base accommodated in the lower rail41, and a protrusion protruding upward through the gap between the base and the upper wall parts of the lower rail41.

A rail locking device43locks a position of the upper rail42with respect to the lower rail41when any external operating force is not applied thereto, and enables the upper rail42to move with respect to the lower rail41when an external operating force is applied thereto. The rail locking device43may have a known configuration, and may be provided in each of the right and left lower rails41, for example. The rail locking device43includes engaging pieces (not shown) engageable with the lower rail41and the upper rail42, an urging member (not shown) configured to urge the engaging pieces in such a direction that the engaging pieces are in contact with the lower rail41and the upper rail42, respectively, and a common rail lock operating lever43A connected to the engaging pieces and protruding outward from the lower rail41. The rail lock operating lever43A is common to the right and left slide rails34. In an initial state where the rail lock operating lever43A is not operated, the right and left slide rails34lock the position of the upper rail42with respect to the lower rail41as the engaging pieces urged by the urging member engage with the lower rail41and the upper rail42. In an operation state where the rail lock operating lever43A is operated against an urging force of the urging member, the right and left slide rails34enable the upper rail42to move with respect to the lower rail41as at least one of the engaging pieces disengages from at least a corresponding one of the lower rail41and the upper rail42.

The rail lock operating lever43A is coupled to the backside frame21on the left seat back frame8L via a second control cable (power transmission member)45(seeFIG. 2). When the seat back6L is folded toward the seat cushion5L at angles within a prescribed angular range, the second control cable45is pulled toward the side of the seat back frame81L to operate the rail lock operating lever43A. In this way, when the seat back6L is folded toward the seat cushion5L, the rail locking device43is unlocked for a certain period of time to thereby enable the upper rail42to move with respect to the lower rail41. When the seat back6L is completely folded onto the seat cushion5L, the tension applied to the second control cable45is reduced to bring the rail locking device43in its locking state again.

As shown inFIG. 3, the lower rail41of the slide rail34on the left side is coupled to the left rotating member33L. Specifically, a front end portion of the lower rail41is received in the groove portion formed by the third member39of the rotating member331L and fastened to the lower wall part39A of the third member39and the bottom wall part38A of the second member38by fastening members such as bolts. When being coupled to the rotating member33L, the lower rail41is arranged to be positionally offset to the left with respect to the support shaft32and the first member37.

As shown inFIGS. 3 and 4, a reinforcing member48, which is a steel-metal member, is coupled to the bottom wall part and the right side wall part at a rear portion of the left lower rail41. The reinforcing member48includes a lower wall part48A extending back and forth along the bottom wall part of the lower rail41, and a side wall part48B protruding upward from the right side edge of the lower wall part48A and extending in the front-rear direction along the right side wall part of the lower rail41, and the reinforcing member48has an L-shaped cross section as seen from the front and the rear. The lower wall part48A of the reinforcing member48is coupled to the bottom wall part of the lower rail41by fastening members such as bolts and nuts. In other embodiments, the side wall part48B of the reinforcing member48may be coupled to the right side wall part of the lower rail41.

A coupling device51is coupled to the rear end portion of the side wall part48B of reinforcing member48. The coupling device51includes a casing comprised primarily of a base plate51A and a cover plate51B, which are steel-metal members, and a hook-shaped latch51C rotatably supported by and in the casing. The base plate51A and the cover plate51B are arranged such that their right and left main faces are opposed to and face each other. The cover plate51B is fastened to the base plate51A at its front and rear ends, and has an intermediate portion between the front and rear ends bulges away from the base plate51A. As a result, an internal space is defined between the base plate51A and the cover plate51B at the intermediate portion between the front and rear ends. The portions defining the internal space between the base plate51A and the cover plate51B are fastened to each other via spacers (not shown). The portion of the cover plate51B forming the inner space has its lower edge, which is bent toward the base plate51A so as to close the lower edge of the inner space.

In the lower portions of the base plate51A and the cover plate51B, slits51D are defined through the thicknesses of the plates and extend upward. The slits51D defined in the base plate51A and the cover plate51B are formed to have the same shapes when viewed from right and left sides. The latch51C is arranged in the internal space and is rotatably supported by the base plate51A and the cover plate51B. The latch51C is rotatable around a rotation shaft extending in the right-left direction and is rotated between a lock position in which the latch protrudes to lower parts (opening end sides) of the slits51D and a unlock position in which the latch51C is retreated from the slits51D. The latch51C is urged toward the lock position by a spring.

The coupling device51is arranged so that the base plate51A is in contact with the right side face of the side wall part48B of the reinforcing member48, and is fastened to the side wall part48B of the reinforcing member48by one or more fastening members such as bolts and nuts, which fastening members combine the cover plate51B, the base plate51A, and the side wall part48B of the reinforcing member48together. The coupling device51is fastened to the side wall part48B of the reinforcing member48by the fastening members at one position on the front end portion and at two positions at the rear end portion. In other embodiments, the fastening member fastening the cover plate51B to the base plate51A and the fastening member fastening the cover plate51B to the reinforcing member48may be separate fastening members. The coupling device51is arranged such that, when the coupling device51is coupled to the reinforcing member48, an upper part of the coupling device51overlaps the lower rail41when viewed from right and left, and the slits51D are located below the bottom wall part of the lower rail41. In this case, an upper part of the latch51C may be arranged so as to overlap the lower rail41viewed from right and left.

As shown inFIG. 3, the support shaft32and the coupling device51are disposed positionally offset to the same side (right side) with respect to the lower rail41. In other words, the coupling device51is disposed at a location straight rearward and separated from the support shaft32.

As shown inFIG. 1, the lower rail41of the right slide rail34is coupled to the right rotating member33R. Specifically, the front end portion of the lower rail41is received in the groove portion of the rotating member33R and fastened to the rotating member33R by one or more fastening members such as bolts and nuts. The reinforcing member48and the coupling device51are provided on a rear portion of the right lower rail41in the same manner as the left lower rail41. The reinforcing member48and the coupling device51are configured and arranged in the right slide rail34in a bilaterally symmetric manner with the above-described the reinforcing member48and the coupling device51in the left slide rail34, and thus these elements in the right slide rail will not be discussed here.

The upper rail42of the left slide rail34is coupled to the left cushion side frame14and the upper rail42of the right slide rail34is coupled to the right cushion side frame14. When viewed from above, the left slide rail34and the left cushion side frame14are arranged so as to overlap each other, and the right slide rail34and the right cushion side frame14are arranged so as to overlap each other.

As shown inFIGS. 1 and 2, strikers52protruding upward are provided on the floor3in regions corresponding to the slits51D of the right and left coupling devices51. Each striker52includes a pair of right and left pillars extending upward from the floor3and a beam crossing and connecting the upper ends of the pillars to form a gate-like shape.

As shown inFIG. 2, when the left seat1takes the usable position, the upper ends of the slits51D of the right and left coupling devices51rest on the beams of the strikers52provided at locations corresponding to the coupling devices51of the seat. An outer edge (lower edge) of each latch51C which is in its locked position is inclined with respect to the horizontal plane. As a result, when the striker52enters the slit51D, the striker52pushes the latch51C toward its unlock position against an urging force generated by the urging member. When the striker52reaches the upper end portion of the slit51D, the latch51C returns to the lock position by the urging force generated by the urging member so as to prevent the striker52from leaving the slit51D.

As shown inFIGS. 8 and 9, each of the right and left latches51C is connected to an unlatch lever55via a corresponding third control cable53and a connecting mechanism54. The unlatch lever55is connected to a strap101, which an occupant can grasp in order to perform a pulling operation.

As shown inFIG. 2, an urging member56is provided between the left rotating member33L and the left cushion side frame14for urging the upper rail42and the seat cushion frame7L frontward relative to the lower rail41. In the present embodiment, the urging member56is a tension coil spring having one end hooked on the third member39of the rotating member33L and the other end hooked on a spring engaging piece57provided on the left side cushion side frame14.

As shown inFIG. 4, a bracket58protruding downward is coupled to a front part of the side wall part48B of the left reinforcing member48. As shown inFIGS. 2 to 6, an urging device60is provided between the left support member31and the left bracket58. The urging device60is a linearly expandable and contractible device including a cylinder60A and a rod60B, in which the rod60B is capable of advancing and retracting in the longitudinal direction with respect to the cylinder60A and is urged in such a direction as to protrude out of the cylinder60A. In the present embodiment, the urging device60is a known gas spring where compressed gas is contained in the cylinder60A. In other embodiments, the urging device60may include the rod60B urged against the cylinder60A by other urging means such as a compression coil spring. When being contracted, the urging device60generates resistance force caused by the compressed high pressure gas, and can also function as a damping device. When the coupling device51is coupled to the striker52, the urging device60is contracted in such a state that the urging force is generated within the device.

In the present embodiment, the urging device60extends in the front-rear direction, and the front end of the urging device60, which is a proximal end part of the cylinder60A, is rotatably connected to the right side wall of the support member31so as to be rotatable about an axis extending in the right-left direction, whereas a rear end of the urging device60, which is a distal end part of the rod60B, is rotatably connected to the bracket58so as to be rotatable about an axis extending in the right-left direction. As shown inFIG. 3, the support shaft32, the urging device60, and the coupling device51are arranged on an imaginary straight line extending in the front-rear direction.

As shown inFIGS. 2 to 4 and 7, a slide position detecting device62is provided between the upper rail42and the lower rail41of the left slide rail34for detecting whether or not the upper rail42is located at a prescribed front end position with respect to the lower rail41. The slide position detecting device62includes an engaging plate63coupled to the third member39of the rotating member33L, a bracket64coupled to the upper rail42, a first link65, and a second link66, and the first and second links are members rotatably supported by the brackets64. The engaging plate63is formed as a part of the third member39, extends out to the left from the upper edge of the left side wall, and has upper and lower main faces. A front portion of the engaging plate63defines an engaging notch63A extending through the thickness of the engaging plate in the vertical direction (in the up-down direction).

The bracket64has a base64A coupled to the upper rail42and a support portion64B extending from the base64A above the upper side of the engaging plate63, and the support portion64B has main faces facing right and left and extending in the front-rear direction above the engaging plate63. The first link65and the second link66are rotatably supported on the left side face of the support portion64B so as to be rotatable about an axis extending in the right-left direction. The first link65is disposed in a rear portion the support portion64B, and includes an abutting piece65A and a first engaging piece65B which protrude in different radial directions around the rotation axis of the first link65. The abutting piece65A is formed to be longer than the first engaging piece65B in the radial direction. The first link65is urged in the clockwise direction when viewed from left by a first spring65C, which is a screw recoil spring provided between the first link65and the bracket64. A stopper (not shown) is provided in the bracket64for restricting the rotation of the first link65in the clockwise direction at a prescribed position. As shown inFIG. 7A, when the first link is in an initial position where the first link65abuts against the stopper, the abutting piece65A extends downward from the rotation axis of the first link65, and the first engaging piece65B extends obliquely frontward and downward from the rotation axis of the first link65.

The second link66is provided on the support portion64frontward of the first link65B. The second link66includes a second engaging piece66A, a locking piece66B, and an operating piece66C, which are plate pieces protruding in different radial directions about the rotation axis of the second link66. The second link66is urged in the counterclockwise direction when viewed from left by a second spring66D, which is a tension coil spring provided between the second link66and the bracket64. The locking piece66B is formed in a hook shape curved in the counterclockwise direction when viewed from left. A fourth control cable71and a fifth control cable72are coupled to the operating piece66C such that the fourth control cable71has one end coupled to the operating piece66C and the other end coupled to the connecting mechanism54, and that the fifth control cable72has one end coupled to the operating piece66C and the other end coupled to the rail lock operating lever43A.

A, a stopper (not shown) is provided on the bracket64for restricting the rotation of the second link66in the counterclockwise direction at a prescribed position. As shown inFIG. 7B, when the second link66abuts against the stopper, the second link66is in its operating position. When the second link66is in the operating position, the locking piece66B having a hook-like shape protrudes downwards and is allowed to enter the engaging notch63A of the engaging plate63. As shown inFIG. 7A, when the first link65is in the initial position, the second engaging piece66A abuts against the first engaging piece65B in the radial direction so that the rotation of the second link66in the counterclockwise direction is restricted. In this state, the second link66is in its non-operating position. When the second link66is in the non-operating position, an end of the locking piece66B is separated above from an upper face of the engaging plate63.

As shown inFIG. 7A, when the seat cushion5L and the upper rail42are located rearward of the lower rail41, the first link65is located away from the engaging plate63. In this state, the first link65is in the initial position, and the first engaging piece65B and the second engaging piece66A are in contact with each other, whereby the second link66takes the non-operating position. When the seat cushion5L and the upper rail42move frontward from this state relative to the lower rail41, the abutting piece65A of the first link65strikes a trailing edge of the engaging plate63, whereby the first link65rotates in the counterclockwise direction against the urging force of the first spring65C to thereby move onto the upper face of the engaging plate63. As a result, the first engaging piece65B and the second engaging piece66A are disengaged from each other so that the second link66is rotated in the counterclockwise direction by the urging force generated by the second spring66D, and an end of the locking piece66B slidingly contacts the upper face of the engaging plate63. Then, when the seat cushion5L and the upper rail42further move frontward with respect to the lower rail41and reach the front end position, the locking piece66B enters the engaging notch63A of the engaging plate63as shown inFIG. 7B, whereby the seat cushion5L is secured to its front end position with respect to the lower rail41. As the second link66is rotated from the non-operating position to the operating position, the fourth control cable71is pulled toward the second link66side.

Operating the rail lock operating lever43A allows the locking piece66B and the engaging notch63A to be disengaged with each other. When the rail lock operating lever43A is operated, the fifth control cable72is moved to cause the second link66to be rotated in the clockwise direction against the urging force generated by the second spring66D so that the locking piece66B is pulled out from the engaging notch63A. When the seat cushion5L moves rearward with respect to the lower rail41and the abutting piece65A moves away from the engaging plate63, the first link65returns to the initial position by the first spring65C and the second link66is held in the non-operating position.

The connecting mechanism54is provided between the unlatch lever55and the third control cable53and is configured to switch power transmission connection and disconnection between the unlatch lever55and the third control cable53. Specifically, the connecting mechanism54does not transmit an operating force applied to the unlatch lever55when the connecting mechanism is not pulled by the fourth control cable71and is in its disconnection state, and transmits an operating force applied to the unlatch lever55to the third control cable53when the connecting mechanism is pulled by the fourth control cable71and is in its connection state.

Various known mechanisms can be used as the connecting mechanism54. For example, as shown inFIG. 8, the connecting mechanism54preferably includes a base plate81on which the unlatch lever55is rotatably supported, an output lever82rotatably supported on the base plate81so as to be rotatable coaxially with the unlatch lever55, and a switch lever83rotatably supported on the base plate81so as to be rotatable about a rotation axis which is not coaxial with that of the unlatch lever55. Preferably, the base plate81is supported on the lower face of the cushion pan frame18. The third control cable53is coupled to the output lever82, and the fourth control cable71is coupled to the switch lever83. A coupling plate84is coupled to the switch lever83, and a coupling pin85is provided to protrude from the coupling plate84. The unlatch lever55defines a first slot87through which the coupling pin85passes, and the output lever82defines a second slot88through which the coupling pin85passes. The first slot87includes a first portion87A extending in a circumferential direction around the rotation axis of the switch lever83and a second portion87B extending from one end of the first portion87A in the circumferential direction around the rotation axis of the unlatch lever55. The second slot88is defined as a slot having the same shape as and opposed to the first portion87A of the first slot87. The unlatch lever55and the switch lever83are urged by springs91,92in their initial positions, respectively.

As shown inFIG. 8A, when the switch lever83is not pulled by the fourth control cable71, the switch lever83is in the initial position and the coupling pin85is located at an end position of the first portion87A where the second portion87B is adjacent thereto. This state is referred to as a disconnected state. In the disconnected state, since the coupling pin85is in the second portion87B of the first slot87, the rotation of the unlatch lever55does not cause the coupling pin85to be pressed by the unlatch lever55so that the coupling pin85remains in its initial position. This means that the output lever82also remains at its initial position in the same manner as the coupling pin85. Referring toFIG. 8B, when the switch lever83is pulled by the fourth control cable71, the switch lever83is in its post-operating state in which the coupling pin85is located at the other end of the first portion87A opposite to the second portion87B side. This state is referred to as a connected state. In the connected state, when the unlatch lever55rotates, the coupling pin85is pushed by the unlatch lever55to rotate together with the unlatch lever55. In this state, the output lever82is pushed by the coupling pin85to rotate together with the unlatch lever55, pulls the third control cable53, and unlock the latch51C of the coupling device51.

Preferably, an engaging groove55A is formed at an end of the unlatch lever55, and a strap101is hooked by the engaging groove55A. As shown inFIGS. 9A and 9B, the strap101includes a core material102and a band-like member103wrapping around the core material102. The band-like member103is formed by laminating multiple pieces of woven fabric each other or by folding and laminating one piece of woven fabric, and the band-like member103has an elongated shape. The core material102is formed of a flexible resin such as elastomer or silicone resin. The core material102is a plate piece extending along the band-like member103, and has a thick part102A which is located in an end in the longitudinal direction and thicker than the other part. The thick part102A may be formed in a columnar shape, for example. The core material102and the band-like member103are stitched together by sewing. The thick part102A is included in the strap101so that the strap101has an engaging part101A which is thicker than the other part in the longitudinal direction. The strap101is provided with annular parts101B formed by the band-like member103at both proximal and distal ends in the longitudinal direction.

In the rear portion of the seat cushion5L, a cover member105is provided for covering a rear part of the rear member16. The cover member105defines a slit-like insertion hole105A extending through the thickness of the cover member. The insertion hole105A has a size that allows the strap101to pass through except for the engaging part101A thereof. Edges of the insertion hole105A have a large wall thickness to be more rigid. The strap101is arranged to pass through the insertion hole105A, and the proximal annular part101B is hooked on the engaging groove55A of the unlatch lever55. The engaging part101A of the strap101is disposed outward (rearward) of the insertion hole105A. This prevents the engaging part101A of the strap101and the distal end thereof from being drawn inward of the insertion hole105A. Since the distal end of the strap101protrudes outwardly from the insertion hole105A to form a substantially straight line shape, a user can easily grasp the strap101.

The operation of the so configured left seat1will be described. When a user operates the reclining operating lever, the first control cable is pulled to unlock the reclining mechanism(s)26. As a result, the seat back6L is allowed to rotate frontward with respect to the seat cushion5L.

When the seat back6L is folded toward the seat cushion5L at angles within a prescribed angular range, the second control cable45is pulled to operate the rail lock operating lever43A. As a result, the rail locking device43is unlocked for a certain period of time to thereby enable the seat cushion5L to move to its front end position by the urging force generated by the urging member56. When the seat back6L is completely folded toward the seat cushion5L, the tension applied to the second control cable45is reduced to bring the rail locking device43in the locking state.

When the seat cushion5L moves to the front end position, the second link66of the slide position detecting device62rotates, whereby the fourth control cable71is pulled. This brings the connecting mechanism54in its connecting state, under which, when the unlatch lever55is operated by the user via the strap101, the operating force is applied to the latch51C via the connecting mechanism54and the third control cable53, thereby decoupling the coupling device51from the striker52. When the coupling device51is decoupled from the striker52, the extension of the urging device causes the seat cushion5L to rotate frontward about the support shaft32to thereby take a prescribed upright position. The user can press the seat cushion5L in the upright position to further rotate frontward to thereby take a tumbled stowed position.

When the seat back6L is folded onto the seat cushion5L and the seat cushion5L is located at its front end position, the user can manually operate the rail lock operating lever43A to cause the seat cushion5L to move with regard to the lower rail41. The folded seat cushion5L and the seat back6L may move to the rear end position with respect to the lower rail41such that the rear face of the seat back6L cooperates with a seat in the back row behind the left seat1or with the floor3to form a floor surface of a luggage room or space.

In the left seat1configured as described above, the support shafts32and the coupling devices51, which are secured to the floor3, are disposed both frontward and rearward of the urging device60which generates an urging force in the front-rear direction. Thus, this configuration restricts the expansion of the urging device60, thereby suppressing the deformation of the lower rail41and the seat cushion5L to which the urging device60is coupled. As a result, the upper rail42is allowed to smoothly move relative to the lower rail41.

Since the rear end of the urging device60and the coupling device51are coupled to the reinforcing member48, the urging force generated by the urging device60is transmitted to the coupling device51via the reinforcing member48and is hardly transmitted to the lower rail41, resulting in that the deformation of the lower rail41is suppressed.

In the present embodiment, since the coupling device51is provided on the side of the lower rail41such that, when viewed from the right-left direction, the coupling device51partially overlaps the lower rail41and the length of a part of the coupling device51which protrudes downward beyond the lower rail41is small compared to cases where the coupling device51is disposed below the lower rail41. This means that the distance between the lower rail41and the floor3is smaller, thereby resulting in a smaller dead space created between the seat cushion5L and the floor3.

The urging device60is arranged on the right side of the left lower rail41; that is, on a center portion of the left seat1in the right-left direction. Thus, this configuration reduces a difference between the loads applied on the right and left halves of the seat cushion5L, thereby suppressing the deformation of the seat cushion5L. Since the support shaft32, the coupling device51, and the urging device60are disposed within an inner region of the vehicle seat, the support shaft32, the coupling device51, and the urging device60are hardly visible from the outside and a user is prevented from unintentionally touching the urging device60or other elements under the vehicle seat.

When the seat back6L of the seat1is folded onto the seat cushion5L, the rail locking device43is unlocked, thereby causing the seat cushion5to move to the front end position with respect to the lower rail41by the urging force generated by the urging member. Since, when the seat back6L is folded onto the seat cushion5L, the seat cushion5L is thus automatically moved to the front end position with respect to the lower rail41, the stowing operation is easy for users. Furthermore, since the slide position detecting device62and the connecting mechanism54allow the coupling device51to be unlocked only when the seat cushion5L is at the front end position with respect to the lower rail41, an unintentional, unnecessary unlocking operation is prevented from occurring.

The right seat2generally has a right-left reversal structure of the left seat1. Features of the right seat2which are different from the left seat1will be described below. As shown inFIG. 1, the seat cushion frame7R of the right seat2includes a pair of right and left cushion side frames120extending in the front-to-rear direction, a front member121crossing and connecting respective front end portions of the cushion side frames120, a rear member122crossing and connecting respective rear end portions of the cushion side frames120, a first intermediate member123crossing and connecting respective intermediate portions between the respective front and rear end portions of the cushion side frames120, an intermediate frame125extending in the front-rear direction and having a front end coupled to an intermediate portion in the right-left direction of the first intermediate member123and a rear end coupled to an intermediate portion in the right-left direction of the rear member122, a second intermediate member126extending in the right-left direction and coupled to the intermediate frame125and the left cushion side frame120, and a plate-shaped cushion pan frame127crossing and hanging between respective intermediate portions of the first intermediate member123and the rear member122, where the intermediate portions of the first intermediate member123and the rear member122are located between the right cushion side frame120and the intermediate frame125. The front member121, the front end portion of the left cushion side frame120, and the second intermediate member126are formed of curved continuous metal pipes.

As shown inFIGS. 1 and 10, the right seat also includes a bracket130crossing and hanging between the second intermediate member126and the rear member122. The bracket130includes an upper wall part130A supported on and welded to upper faces of the second and intermediate members126and122, and a vertical wall130B extending downward from the upper wall part130A and having right and left main faces. A left supporting plate131and a right supporting plate132are coupled to the vertical wall130B by bolt fastening or other fastening methods. The left supporting plate131and the right supporting plate132are arranged along the vertical wall130B with their main faces facing to the right and left, respectively. Formed at a lower end portion of the left supporting plate131is a left hook part131A which is curved leftward and upward. Formed at a lower end portion of the right supporting plate132is a right hook part132A which is curved rightward and upward.

The right cushion side frame120and the intermediate frame125of the right seat2are coupled to the respective upper rails42of the right and left slide rails34. The slide rail34is the same slide rail as that of the left seat1. Each slide rail34is rotatably provided on the floor3by a support member136coupled to the floor3and a rotating member137rotatably supported at a front end of the support member136. The rotating member137on the left side is comprised of multiple steel-metal members, and forms a groove portion extending in the front-rear direction. The lower rail41on the left side is arranged within the groove portion of the left rotating member137. Formed at an upper end portion of the left side wall137A of the left rotating member137is a hook part137B extending in the front-rear direction. The hook part137B of the rotating member137is hooked on the right hook part132A of the right supporting plate132.

The same coupling device51as that of the left seat1is coupled to the left side wall137A of the left rotating member137. A reinforcing bracket140is coupled to the cover plate51B which defines the left side face of the coupling device51. Formed at an upper end portion of the reinforcing bracket140is a hook part140A, which is hooked on the left hook portion131A of the left supporting plate131. Preferably, the reinforcing bracket140is tightened together with the coupling device51to the left rotating member137.

Although the present invention has been described based on a specific embodiment, the embodiment is not intended to limit the scope of the present invention. Many modifications and variations of the invention are possible in light of the above teachings, and thus, the invention may be practiced other than as specifically described within the scope of the appended claims.

GLOSSARY