Front row assembly having fold flat mechanism with forward cushion movement

A vehicle seat assembly includes a seat cushion coupled between a pair of risers and a seat back pivotally coupled thereto. A pair of front cushion support links and a pair of rear cushion support links are coupled between the seat cushion and the risers for pivotally supporting and guiding the seat cushion. A fold flat mechanism includes a transfer link operatively coupled between the rear cushion support link and the seat back for transferring pivotal movement of the seat back through the transfer link to each of the front and rear seat cushion support links to automatically move the seat assembly between a seating position wherein the seat back is in an upright position and the seat cushion is spaced above the floor, and a stowed position wherein the seat back is pivoted to a fold flat position and the seat cushion is lying flat against the floor.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a seat assembly for an automotive vehicle. More particularly, the invention relates to a seat assembly having a fold flat mechanism for pivoting the seat back flat against the seat cushion while simultaneously moving the seat cushion forward and flat against the floor of the vehicle.

2. Description of the Related Art

Automotive vehicles include seat assemblies for supporting occupants within the vehicle. Seat assemblies are typically arranged within at least a front, or first row, and a rear, or second row, of the vehicle. Each seat assembly typically includes a generally horizontal seat cushion coupled to a generally vertical seat back. It is known in the seating art to provide a stowable seat assembly movable between a seating position for supporting a seat occupant above a floor of the vehicle and a stowed position lying flat against the floor, or nested within a recess formed in the floor. Typically, in such seat assemblies, the seat back is pivotally coupled to the seat cushion for movement between a generally upright position and a forward fold flat position overlying the seat cushion.

Additionally, the seat cushion often includes a four bar linkage mechanism extending between the seat cushion and the floor of the vehicle for moving the seat assembly between a seating position spaced above the floor and a stowed position resting against the floor. The pivotal movement of the seat back is actuated and controlled independently of the movement of the seat cushion, thus requiring separate operation to move the seat assembly from the seating position to the stowed position. Therefore, it remains desirable to provide a mechanism coupled between the seat back and the seat cushion for moving the seat assembly between the seating position and the stowed position in response to pivotal movement of the seat back between the generally upright position and the forward fold flat position.

SUMMARY OF THE INVENTION

According to one aspect of the invention, a seat assembly is adapted to be coupled to the floor of an automotive vehicle. The seat assembly includes a pair of spaced apart risers for mounting the seat assembly to the floor. A seat cushion is coupled between the risers and extends between a forward end and a rearward end. A seat back extends between an upper end and a lower end. A support bracket is adapted to be coupled between the seat back and each of the respective risers. A recliner mechanism is pivotally coupled between the support bracket and the lower end of the seat back for supporting the seat back through pivotal movement between an upright position and a fold flat position overlying the seat cushion. A pair of front cushion support links is coupled between the forward end of the seat cushion and the risers for pivotally supporting and guiding the seat cushion. A pair of rear cushion support links is coupled between the rearward end of the seat cushion and the risers for pivotally supporting and guiding the seat cushion. A fold flat mechanism is operatively coupled between the rearward end of the seat cushion and the lower end of the seat back. The fold flat mechanism includes a transfer link extending between a first end pivotally connected to the rear cushion support link and a second end operatively coupled to the lower end of the seat back for transferring pivotal movement of the seat back through the transfer link to each of the front and rear seat cushion links to automatically move the seat assembly between a seating position, wherein the seat back is in the upright position and the seat cushion is spaced above the floor and a stowed position, wherein the seat back is pivoted to the fold flat position and the seat cushion is lying flat against the floor.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring toFIGS. 1 and 2, a seat assembly for an automotive vehicle is generally shown at10. In the first embodiment shown, the seat assembly10is for a second row, or passenger row, of the vehicle. It will, however, be appreciated that the seat assembly10may be utilized in any seating position within the vehicle without varying from the scope of the invention. The seat assembly10includes a seat cushion12for supporting a seat occupant above a floor14of the vehicle. The seat assembly10also includes a seat back16operatively coupled to the seat cushion12and movable between a generally upright position, shown inFIG. 1, and a forward fold flat position, shown inFIG. 2, overlying the seat cushion12. A recliner mechanism18, as is commonly known in the art, is provided for pivotal movement of the seat back16between the upright position and the fold flat position. The recliner mechanism18may also provide fore and aft pivotal reclining adjustment of the seat back16relative to the seat cushion12for occupant comfort. The seat assembly10is moveable between a seating position, as shown inFIG. 1, wherein the seat back16is in the upright position and the seat cushion is spaced above the floor14of the vehicle, and a stowed position, as shown inFIG. 2, wherein the seat back16is pivoted to the fold flat position and the seat cushion12is lying flat against the floor14.

Referring toFIGS. 3 through 5, the seat cushion12includes a seat pan20having opposing top22and bottom24contoured surfaces and extending between a forward end26and a rearward end28. The bottom surface24of the seat pan20is shaped to match a corresponding contour on the floor14of the vehicle such that the seat cushion12lies flush against the floor14when the seat assembly10is in the stowed position.

The seat cushion12also includes a pair of spaced apart risers30positioned on opposing sides of the seat pan20for supporting the seat pan20and the seat back16. Each of the risers30extend between a forward end32and a rearward end34. A pair of spaced apart track assemblies36mounted to the floor14of the vehicle provides selective fore and aft sliding adjustment of the seat assembly10within the vehicle as is commonly known in the art.

Referring toFIG. 4, a vertical height adjuster or four-bar linkage, generally shown at38, operatively couples the track assemblies36and the risers30to provide selective vertical height adjustment of the seat assembly10relative to the floor14and simultaneously providing fore and aft movement of the seat assembly10during vertical height adjustment. More specifically, the vertical height adjuster38includes a pair of front adjuster links40and a pair of rear adjuster links42. Each of the front adjuster links40extend between a first pivot44and a second pivot46.

The first pivots44pivotally connect the front links40to a mounting bracket48fixedly secured to the respective track assembly36, adjacent a forward end50thereof. The second pivots46pivotally connect the front links40to the respective riser30adjacent the forward end32thereof. Each of the rear adjuster links42extend between a first pivot52and a second pivot54. The first pivots52pivotally connect the rear links42to a mounting bracket56fixedly secured to the respective track assembly36, adjacent a rearward end58thereof. The second pivots54pivotally connect the rear links42to the respective riser adjacent the rearward end34thereof. The vertical height adjuster38also includes an actuator60operatively coupled to at least one of the rear adjuster links42for actuating the vertical height adjuster38thereby pivoting the front40and rear42adjuster links about the respective first pivots44,52to allow selective vertical height adjustment and simultaneous fore and aft movement of the seat assembly10.

The seat cushion12further includes a front support rod62fixedly secured to the bottom surface24of the seat pan20and extending laterally between opposing sides thereof adjacent the forward end26. A rear support rod64is similarly fixedly secured to the bottom surface24and extends laterally between the opposing sides of the seat pan20adjacent the rearward end28. A pair of front cushion support links66is pivotally coupled between the front support rod62and the risers30for pivotally supporting and guiding the seat cushion12. More specifically, each of the front cushion support links66extends between a first end68pivotally connected to a distal end70of the front support rod62and an opposite second end72pivotally connected to the forward end32of the respective riser30. A pair of rear cushion support links74is pivotally coupled between the rear support rod64and the risers30for pivotally supporting and guiding the seat cushion12. More specifically, each of the rear cushion support links74extends between a first end76pivotally connected to a distal end78of the rear support rod64and an opposite second end80. Preferably, each rear cushion support link74has a curvature or bend between the first76and second80ends. The rear cushion support links74are pivotally connected to the rearward end34of the respective riser30by an intermediate pivot pin82positioned between the first76and second80ends.

Referring toFIGS. 4 and 5, the seat back16includes a seat back frame84extending between an upper end86and lower end88. A recliner bracket90extends from each side of the seat back frame84adjacent the lower end88thereof. A support bracket92is pivotally coupled to each of the recliner brackets90and each support bracket92is fixedly secured to the rearward end34of the respective riser30for pivotally supporting the seat back16between the upright position and the fold flat position. Each recliner mechanism18includes a recliner pivot shaft94pivotally connecting the recliner bracket90and the support bracket92to provide pivotal movement of the seat back16between the upright and fold flat positions.

Referring toFIGS. 3 and 4, both lateral sides of the seat assembly10include a fold flat mechanism, generally shown at96. Each fold flat mechanism96is operatively coupled between the seat cushion12and seat back16for automatically moving the seat assembly10between the seating position and the stowed position in response to pivotal movement of the seat back16between the upright position and the fold flat position. The fold flat mechanism96includes a transfer link98extending between opposite first100and second102ends. The first end100is pivotally connected to the second end80of the rear cushion support link74. The second end102is defined by an arcuate, elongated slot104extending between opposite front106and back108ends and is operatively coupled to the lower end88of the seat back frame84. More specifically, a connecting bracket110is fixedly secured to the lower end88of the seat back frame84. A guide pin112extending laterally from the connecting bracket110is disposed in the arcuate slot104for sliding movement therein between the front106and back108ends to provide a lost motion connection between the seat cushion12and seat back16. A bias spring114extends between the rear cushion support link74and the lower end88of the seat back frame84for biasing the seat assembly10to the seating position. Finally, a latch116is pivotally connected to the riser30for hooking engagement with a post118projecting from the rear cushion support link74to selectively lock the seat assembly10in the seating position.

In operation, starting with the seat assembly10in the seating position, the seat cushion12is supported by the seat pan20and spaced above the floor14of the vehicle by the front cushion support links66and the rear cushion support links74as shown inFIGS. 1,3, and4. The seat back16is supported in the upright position by the recliner brackets90. To move the seat assembly10from the seating position to the stowed position, the latch116is released from the post118by any release lever or means commonly known in the art and the recliner mechanism18is released by any means commonly known in the art to unlock and allow the seat back16to pivot forwardly about the recliner pivot shaft94toward the fold flat position shown inFIGS. 2 and 5. Initially, the seat back16pivots independently of any movement of the seat cushion12. The independent pivotal movement of the seat back16is provided by the lost motion connection between the transfer link98and the seat back frame84. As the seat back16pivots forwardly, the guide pin112travels along the arcuate slot104from the front end106to the back end108. Once the guide pin112abuts the back end108of the arcuate slot104the continued pivotal movement of the seat back16pulls upwardly on the transfer link98. The transfer link98, in turn, pulls upwardly on the lower, second end80of the rear cushion support link74to pivot the rear cushion support link74in a first direction about the intermediate pivot pin82. The pivotal movement of the rear cushion support link74in the first direction moves the upper, first end76of the rear cushion support link74forwardly and downwardly which causes forward and downward movement of the front cushion support link66. The pivotal movement of the front66and rear74cushion support links moves the seat pan20, and thus the seat cushion12, forwardly and downwardly relative to the risers30toward the floor14of the vehicle. Thus, in response to pivotal movement of the seat back16from the upright position to the fold flat position, the fold flat mechanism96automatically moves the seat cushion12forwardly and downwardly until the seat cushion12is lying flat against the floor14of the vehicle and the seat assembly10is in the stowed position, as shown inFIG. 5.

To return the seat assembly10to the seating position, the seat back16is simply pivoted upwardly away from the seat cushion12from the fold flat position to the upright position. As the seat back16pivots upwardly, the guide pin112travels along the arcuate slot104from the back end108to the front end106. Once the guide pin112abuts the front end106of the arcuate slot104the continued pivotal movement of the seat back16pushes downwardly on the transfer link98. The transfer link98, in turn, pushes downwardly on the lower, second end80of the rear cushion support link74to pivot the rear cushion support link74in a second direction about the intermediate pivot pin82. The pivotal movement of the rear cushion support link74in the second direction moves the upper, first end76of the rear cushion support link74upwardly and rearwardly which causes upward and rearward movement of the front cushion support link66. The pivotal movement of the front66and rear74cushion support links moves the seat pan20, and thus the seat cushion12, upwardly and rearwardly relative to the risers30away from the floor14of the vehicle. Thus, in response to pivotal movement of the seat back16from the fold flat position to the upright position, the fold flat mechanism96automatically moves the seat cushion upwardly and rearwardly until the seat cushion12is spaced above the floor14and the seat assembly10is in the seating position, as shown inFIG. 3.

Referring toFIGS. 6 and 7, wherein like primed reference numerals represent similar elements as those described above, in a second embodiment of the invention, one lateral side of the seat cushion12′ and seat back16′ are operatively coupled by the fold flat mechanism96′. Referring toFIG. 6, the fold flat mechanism96′ includes a transfer link98′ extending between opposite first100′ and second102′ ends. The first end100′ is operatively coupled to the rear cushion support link74′ and the second end102′ is operatively coupled to the seat back frame84′. More specifically, the fold flat mechanism96′ includes a connecting bracket110′ having a first end120fixedly secured to the recliner bracket90′ of the seat back frame84′ and a second end122pivotally connected to the second end102′ of the transfer link98′. The fold flat mechanism96′ also includes a lost motion link124having a first end126pivotally connected to the first end100′ of the transfer link98′ and an opposite second end128pivotally connected to the second end80′ of the rear cushion support link74′. The lost motion link124provides a lost motion connection between the seat cushion12′ and seat back16′. A transfer pin130projects laterally outward from the lost motion link124between the first126and second128ends thereof for abutting a distal end132of the transfer link98′ extending beyond the first end100′. Finally, a latch116′ is pivotally connected to the riser30′ for hooking engagement with a post118′ projecting from the rear cushion support link74′ to selectively lock the seat assembly10′ in the upright seating position.

Referring toFIG. 7, the fold flat mechanism96′ is operatively coupled to and actuates the rear cushion support link74′ on the other lateral side of the seat assembly10′. More specifically, the rear support rod64′ extends laterally between the first ends76′ of the rear cushion support links74′.

In operation, to move the seat assembly10′ from the seating position to the stowed position, the latch116′ is released from the post118′ by any release lever or means commonly known in the art and the recliner mechanism18′ is released by any means commonly known in the art to unlock and allow the seat back16′ to pivot forwardly about the recliner pivot shaft94′ toward the fold flat position. Similar to that described above with respect to the first embodiment, initially the seat back16′ pivots independently of any movement of the seat cushion12′. The independent pivotal movement of the seat back16′ is provided by the lost motion connection between the transfer link98′ and the rear cushion support link74′. As the seat back16′ pivots forwardly, the connecting bracket110′ pulls upwardly on the transfer link98′. The transfer link98′, in turn, pulls upwardly on the first end126of the lost motion link124causing the lost motion link124to pivot in a first direction about the second end128thereof. Once the transfer pin130abuts the distal end132of the transfer link98′ further pivotal movement between the transfer link98′ and the lost motion link124is prevented. The transfer link98′ and lost motion link124now move upwardly together, as a single link pulling on the lower, second end80′ of the rear cushion support link74′ to pivot the rear cushion support link74′ in the first direction about the intermediate pivot pin82′. The pivotal movement of the rear cushion support link74′ in the first direction moves the upper, first end76′ of the rear cushion support link74′ forwardly and downwardly which causes forward and down-ward movement of the front cushion support link66′. At the same time, the rear support rod64′ causes the rear cushion support link74′ on the other lateral side of the seat assembly10′ to pivot in the first direction about the intermediate pivot pin828′. The pivotal movement of the front66′ and rear74′ cushion support links moves the seat pan20′, and thus the seat cushion12′, forwardly and downwardly relative to the risers30′ toward the floor14′ of the vehicle. Thus, in response to pivotal movement of the seat back16′ from the upright position to the fold flat position, the fold flat mechanism96′ automatically moves the seat cushion12′ forwardly and downwardly until the seat cushion12′ is lying flat against the floor14′ of the vehicle and the seat assembly10′ is in the stowed position.

To return the seat assembly10′ to the seating position, the seat back16′ is simply pivoted upwardly away from the seat cushion12′ from the fold flat position to the upright position. As the seat back16′ pivots upwardly, the connecting bracket110′ pushes downwardly on the transfer link98′. The transfer link98′ and the lost motion link124moving downwardly as the single link, push on the lower, second end80′ of the rear cushion support link74′ to pivot the rear cushion support link74′ in a second direction about the intermediate pivot pin82′. The pivotal movement of the rear cushion support link74′ in the second direction moves the upper, first end76′ of the rear cushion support link74′ upwardly and rearwardly which causes upward and rearward movement of the front cushion support links66′. At the same time, the rear support rod64′ causes the rear cushion support link74′ on the other lateral side of the seat assembly10′ to pivot in the second direction about the intermediate pivot pin82′. The pivotal movement of the front66′ and rear74′ cushion support links moves the seat pan20′, and thus the seat cushion12′, upwardly and rearwardly relative to the risers30′ away from the floor14′ of the vehicle. Thus, in response to pivotal movement of the seat back16′ from the fold flat position to the upright position, the fold flat mechanism96′ automatically moves the seat cushion12′ upwardly and rearwardly until the seat cushion12′ is spaced above the floor14′ and the seat assembly10′ is in the stowed position.