WO1999019165A1

WO1999019165A1 - Rolling stowable seat

Info

Publication number: WO1999019165A1
Application number: PCT/US1998/021824
Authority: WO
Inventors: Alan Sturt; Marcel Corneliu Ban
Original assignee: Lear Corporation
Priority date: 1997-10-15
Filing date: 1998-10-15
Publication date: 1999-04-22
Also published as: AU9805098A

Abstract

A vehicle seat that is folded and stowed in a recess in the floor (16) of a vehicle. A rear portion (28) of the seat has shiftable elements that are moved within channels formed in tracks. The shiftable elements may be rollers that move in box channel tracks. A front portion of the seat is supported by link arms that pivot as the seat is stowed in the recess. Locking pins (66, 68) on the link arms are received in a series of holes that permit fore-and-aft adjustment of the seat position. A seat back panel for the seat back is supported by a parallelogram linkage (130, 132). Pivotal motion of the seat back to a forward, folded position is accompanied by forward movement of the lower seat portion. A seat riser and the seat back linkage are lowered as the seat back is folded forward, thereby reducing the overall stacked height of the folded seat.

Description

ROLLING STOWABLE SEAT

Technical Field

The present invention relates to a stowable vehicle seat .

Background Of The Invention

Passenger cars and trucks are used for transporting passengers and cargo. Passenger seats in vehicles limit the cargo carrying capacity of the vehicle. Minivans and sport utility vehicles have various configurations of passenger seats that are adapted to be converted from a passenger seat to a folded cargo carrying position. Generally, the seat back folds down over the lower seat . While this creates additional cargo carrying capacity, the folded seat back may be a foot to a foot and a half above the floor of the passenger/cargo compartment .

Another approach to the problem of maximizing cargo carrying capacity in a minivan or sport utility vehicle is to provide detachable seats that can be removed from the vehicle leaving a clear, unobstructed cargo floor of maximum height. Conventional seats suffer from the disadvantage that they are heavy and unwieldy. Also, after the seats are removed from the vehicle, they must be stored outside the vehicle typi- cally in an already crowded garage.

Yet another approach is to provide seats that are mounted to the floor of a vehicle on rollers that are received in tracks secured to the floor of the vehicle. In this approach, the seats may be either rolled forwardly or rearwardly in the vehicle so that they are adjacent to one another when folded down. Also, one or more rows of seats may be removed. Depending on whether the seats are left in the vehicle in a folded down condition or removed, this approach suffers from the same disadvantages that were previously described.

The present invention is directed to solving the above problems .

In the case of a contemporary minivan, a sliding side door for the vehicle permits access of passengers to a row of rear seats. In such instances, it is desirable to fold the auxiliary seat forward to facilitate ingress and egress of the rear seat passengers. Contemporary minivans, as well as so-called sport utility vehicles, furthermore may be provided with auxiliary seats rearward of the driver seat and the front passenger seat. These would be positioned on a platform or structural floor panel that accomplishes the secondary purpose of carrying cargo . In such instances the auxiliary seat must be folded forward to provide an extension of the cargo carrying floor area.

In each of these instances, it is necessary to fold the seat back portion of the seat assembly forward over the lower seat portion. The stacked height of the auxiliary seat assembly in its folded state then would be equal to the sum of the height of the seat riser assembly, the height of the lower seat portion and the thickness of the seat back portion. The overall stacked height thus is substantial in prior art designs. This is an inconvenience to passengers as they ingress and egress the vehicle through a side door opening. Furthermore, the stacked height of the auxiliary seat assembly reduces the cargo carrying capacity of the vehicle when the vehicle is adapted for carrying cargo.

Summary Of The Invention

The present invention provides a vehicle seat for a vehicle, such as a minivan or sport utility vehicle, that may be folded down and rolled into a recess formed in the floor of the vehicle to provide a full height cargo area of maximum cargo carrying capacity.

According to the present invention, a seat is provided for a vehicle that has a compartment that may be arranged in a passenger configuration or a cargo carrying configuration. The floor of the compartment defines a recess in which the seat may be wholly or partially stowed. Rear wheel housings extend into the compartment on opposite sides of the floor. The seat includes a lower seat assembly and a seat back assembly that are pivotally connected. Rails defining channels are secured to the wheel housings on opposite sides of the compartment. Shiftable elements, or rollers, are connected to the rear portion on opposite sides of the lower seat assembly and are received in the channels defined by the rails. Link arms are pivotally connected to the front portion of the lower seat and are also pivotally connected to the floor. Locking pins associ- ated with the link arms are provided to selectively lock the shiftable elements to the rails. The seat is converted from the passenger configuration to the cargo carrying configuration by pivoting the seat back onto the lower seat, disengaging the locking pins from the rails, and shifting the lower seat forward by moving the shiftable elements in the channels and pivoting the link arms forward and downward until the lower seat is received in whole or in part in the recess formed in the floor of the vehicle.

According to another aspect of the invention, the rails may be provided with a series of holes spaced along a portion of their lengths. The right and left locking pins may be selectively received in corresponding holes in the rails to permit adjustment of the seat fore and aft . The locking pins may be secured to the link arms with a lever arm or other actuator connected to the locking pins for extending or retracting the locking pins.

According to another aspect of the invention, a rear surface of the seat back is oriented in a sub- stantially horizontal plane when the seat is in the cargo carrying configuration. Provided that the recess in the floor of the vehicle is large enough to accommodate the lower seat and seat back, the rear surface of the seat back may form a continuous surface with the floor of the compartment.

It is an objective of the invention to provide an auxiliary seat assembly that overcomes the shortcomings of prior art designs such as those described in the preceding background discussion. This is accomplished in the improved design of the invention by providing a lower seat portion that consists of a tubular lightweight frame and that is connected through a parallelogram linkage riser to a seat base. Further, the seat back portion of the seat assembly comprises a lightweight tubular frame that is secured by a parallelogram linkage to a back panel and that is pivoted at its lower margin to the seat base so that it can be tilted forward over the lower seat portion.

The riser assembly for the lower seat portion, when the seat back portion is folded forward, is shifted on its parallelogram linkage to a folded state. As the seat back portion is folded forward in this fashion, the parallelogram linkage for the seat back portion allows the lightweight frame for the seat back portion to move toward the back panel . The frame of the seat back portion engages the frame of the lower seat portion, thereby moving the latter as tilting motion of the seat back portion takes place.

These and other advantages and objects of the present invention will be better understood in view of the attached drawings and the following detailed description of the invention.

Brief Description Of The Drawings

FIGURE 1 is a fragmentary perspective view of the passenger compartment of a vehicle with rear seats in a passenger configuration;

FIGURE 2 is a fragmentary perspective view of the passenger compartment of a vehicle with the rear seats in a cargo carrying configuration; FIGURE 3 is a side elevation view of a vehicle showing seats made in accordance with the present invention and showing the seats in a progression of positions between the passenger configuration and cargo carrying configuration;

FIGURE 4 is a fragmentary perspective view of the rails, pivoting links, and shiftable elements made in accordance with the present invention;

FIGURE 5 is a perspective view of an auxiliary seat assembly embodying the features of the invention;

FIGURE 6 is a side view of the seat assembly of Figure 5 ;

FIGURE 7 is an alternate embodiment of the invention which comprises a tandem seat arrangement, each seat of the tandem arrangement embodying the features of the invention illustrated in Figure 5 ;

FIGURE 8 is a perspective view of a roller assembly at the point of contact of the frame for the seat back portion with the frame of the lower seat portion;

FIGURES 9 and 9a are detail sectional views taken along section lines 9-9 and 9a-9a, respectively, in Figure 10 showing a nylon link that is used in the parallelogram linkage for the lower seat assembly;

FIGURE 10 is a schematic representation of a folded seat assembly; FIGURE 10a is a schematic representation of the seat assembly of Figure 11 in its upright state;

FIGURE 11 is a perspective sub-assembly view of the foldable seat assembly of the invention;

FIGURE 11a is a detailed sub-assembly view of a foldable link seen in Figure 5; and

FIGURE 12 is a detail view of a manually operable pin lock for the seat back portion of the seat assembly.

Best Mode For Carrying Out The Invention

Referring now to Figure 1, a seat 10 for a vehicle 12 having a compartment that is converted between a passenger configuration and a cargo carrying configuration is shown. The compartment has a floor 16 that defines a recess 18. The floor 16 is flanked by a right wheel housing 20 and a left wheel housing 22.

The seat 10 is formed by a lower seat assembly 24 having a front portion 26 and a rear portion 28 and a seat back assembly 30 that is pivotally connected to the lower seat assembly 24. The lower seat assembly 24 and seat back assembly 30 are of conventional design including a frame and foam bun that are enclosed in seat covers. Seat back assembly 30 has a rear surface 32 that is oriented in a substantially horizontal plane when the seat is in the cargo carrying configuration. The rear surface 32 is preferably generally planar in shape so that it is generally coplanar with the floor 12. As shown in Figures 2 and 4, a right rail 36 is secured to the right wheel housing 20. The right rail 36 defines a first channel 38. First channel 38 is a box channel having an opening in one side. Left rail 42 is secured to the left wheel housing 22 and defines a second channel 48 which is similar to first channel 38. Right rail 36 and left rail 42 are provided with a series of holes 44 and 46 that are spaced along a portion of their length corresponding to a generally horizontally extending portion of the rails.

A right side shiftable element 50, or roller, is connected to the rear portion 28 of the lower seat assembly 24. Right side shiftable element 50 is received in the first channel 38 of the right rail 36 for movement within or along the first channel 38. The right side shiftable element 50 is preferably a roller but may be of a non-cylindrical configuration that is slidable within the first channel 38. Alternatively, the shiftable element could be a telescopic member received within the channel 38 in which case it would be necessary to angle the channel 38 from the high point at its rear to the level of the floor 16.

A left side shiftable element 52, or roller, is connected to the rear portion 28 of the lower seat assembly 24 and is received in the second channel 48 of the left rail 42 for movement along the second channel 48. The alternative embodiments described in reference to the right side shiftable element 50 are equally applicable to the left shiftable element 52.

A right link arm 54 is pivotally connected on an upper end 56 to the front portion 26 of the lower seat assembly 24. Right link arm 54 is also pivotally connected to the floor 16. A left link arm 60 is similarly pivotally connected on an upper end 62 to the front portion 26 of the lower seat assembly 24 and pivotally connected to the floor 16. Right and left link arms 54 and 60 may be provided in a single unit by providing converging link arms or by providing a plate which serves the equivalent function and would be pivotally connected to both the front portion 26 of the lower seat assembly 24 and the floor 16.

A right locking pin 66 associated with the right link arm 54 selectively locks the right link arm 54 to the right rail 36. A left link arm 60 associated with the left link arm 60 is provided to selectively lock the left link arm 60 to the left rail 42. Right and left locking pins 66 and 68 are selectively received in corresponding holes 44 and 46 in the right and left rails 36 and 42 to permit adjustment of the position of the seat fore and aft .

An actuator 70 is secured to the right and left locking pins 66 and 68. The actuator is actuated to extend and retract the right and left locking pins 66 and 68 relative to the right and left link arms 54 and 60.

To convert the seat from the passenger configuration to the cargo carrying configuration, first, seat assembly 30 is pivoted onto the lower seat assembly 24. Right and left locking pins 66 and 68 are disengaged from right and left rails 36 and 42, respectively, and lower seat assembly 24 is shifted forward by moving right and left side shiftable elements 50 and 52 forward in first and second channels 38 and 48, respectively. The upper ends 56 and 62 of right and left link arms 54 and 60 are pivoted forwardly and downwardly until the lower seat assembly 24 is received in the recess 18 formed in the floor 16 of the vehicle 12.

The seat may be converted from the cargo carrying configuration to the passenger configuration by lifting the lower seat assembly 24 with the seat back assembly 30 folded over it from the recess 18. Right and left link arms 54 and 60 are pivoted upwardly and rearwardly while right and left side shiftable elements 50 and 52 are shifted rearwardly in first and second channels 38 and 48, respectively. Right and left locking pins 66 and 68 are received in the holes 44 and 46 in right and left rails 36 and 42 to lock the right and left link arms 54 and 60 in place in the channels. Preferably, a series of holes 44 and 46 are provided in the right and left rails 36 and 42 to permit adjustment of the position of the seat fore and aft. The seat back assembly 30 is then pivoted to its upright position relative to the lower seat assembly 24.

Depending upon the depth of the recess 18 relative to the floor 16, the lower seat assembly 24 and seat back assembly 30 may be either fully disposed in the recess 18 or partially disposed in the recess 18 in the cargo carrying configuration.

For convenience, an actuator 70 is secured to right and left locking pins 66 and 68. Actuator 70 is preferably a spring-biased member that is connected to both the right and left locking pins 66 and 68 so that only one actuator 70 must be actuated to extend and retract both right and left locking pins 66 and 68.

Figure 5 shows a modified auxiliary seat assembly embodying the features of the invention. Reference numeral 80 generally designates the lower seat portion and reference numeral 82 generally designates the upright seat back portion. A stationary base or mounting frame is generally designated by reference numeral 84.

The base 84 can be secured to the floor plan structure of the vehicle. In the embodiment shown in Figure 5, it is secured by means of a roller and track assembly 86. For purposes of the description of the invention, however, the base 84 functions as any sta- tionary base that may be secured to the floor plan structure of a vehicle.

The lower seat portion 80 comprises a transverse frame member 88 which is joined to and integrally formed with two frame side members 90 and 92. Frame side member 90 is joined to a forward parallelogram link which may be formed of nylon, as indicated at 94 in Figures 5 and 11a. A pair of eyelets and a hinge pin 98 pivotally connect link 94 to the side frame 90. The lower end of the link 90 is connected pivotally by pivot pin 100 to an upright flange 102 of the base 84. A lower flange 104 of the base 84 could be bolted by anchor bolts or other suitable fastening devices to the floor of the vehicle, although in the particular embodiment shown in Figure 5, the base 84 is secured in place by the track assembly 86. A second link, which also may be formed of nylon, is shown at 106. The upper end of the link 106 is pinned at 108 to the frame side member 90 thereby providing a pivotal connection that is the equivalent of the connection between the link 94 and the side frame member 90. The lower end of the link 106 is connected pivotally to one end 110 of a cross bar 112, the latter extending transversely across the seat assembly to the opposite frame side member 92.

In the embodiment shown in Figure 5, the cross bar 112 is joined to a roller 114 which operates in the track assembly 86. In the absence of the track assembly, however, the end 100 of the cross bar 102 would be secured to the base 84.

The seat back portion comprises an upper frame member 116 and two frame side members 118 and 120 which are secured together, as shown, to form an integral, continuous frame structure. The upper frame member 116 extends transversely across the seat assembly. It may be adapted to carry passenger head restraints 122 and 124.

The lower end of frame side member 118 is received in a semi-circular frame extension or bracket 126. Bracket 126, in turn, is pivotally connected to the end 110 of the cross bar 112 so that the seat back assembly can be tilted about the axis of the cross bar 112.

The bracket 126 carries a roller cam follower portion 128 which extends in the direction of the axis of the frame side member 118. The cam surface 128 is engaged by a roller assembly 60, which will be described with reference to Figure 9.

The seat back frame 118 is supported by four parallelogram linkages 130 and 132 adjacent the side member 118 and by parallelogram linkages 134 and 136 adjacent the side member 120.

As seen in Figure 6, parallelogram links 130 and 132 are secured by pin and eyelet connection 140 and 142, respectively, to back panel 138. They are pinned at the other ends thereof to the frame side member 118 by pin and eyelet connections 144 and 146, respectively. Corresponding connections are provided for the parallelogram linkage members 134 and 136 at the opposite side of the frame assembly, as seen in Figure 5 at 148 and 150.

The back panel 138 has an auxiliary panel or extension 152 which is hinged at 154 to the upper margins of the panel . When the seat assembly is in its folded state, the auxiliary panel or extension 152 can be folded over the head rest 122 and the head rest 124 thereby providing a generally continuous platform surface.

The cam surface 128, as best seen in Figure 6, engages roller 130. This roller is seen best in Figure 8. It is carried on a roller supporting plunger or rod 156, which is received within the frame side member 90 of the frame 80 for the lower seat portion. Rod 156 extends in the direction of the axis of the frame side member 90. A spring seat element 158 is carried on the rod 156. A spring, shown in phantom at 160, acts on the rod 156 and the seat element 158 and tends normally to urge the roller 170 in a leftward direction, as seen in the perspective view of Figure 8.

The roller 130 is recessed on its periphery as shown at 162. This recess allows the roller to straddle the cam surface at 128.

When the frame for the seat back portion is tilted forward about the axis of the rollers 114 to its folded position, the rollers 130 shift the frame 80 for the lower seat portion. This causes the parallelogram linkage elements at 106 and 94 to pivot about their respective pivot axes as the frame 80 shifts in a leftward direction from the position shown in Figure 5. As it is shifted in a leftward direction in this fash- ion, the frame is lowered because of the parallelogram linkage mechanism until it assumes a position generally coplanar with respect to the base 102.

As the seat back frame is tilted forward, the rollers 130 ride along the cam surface 128 so that the force applied to the lower seat portion frame 80 is continuous .

The opposite side of the seat assembly illustrated in Figure 5 is provided with a parallelogram linkage mechanism including linkage elements 164 and 166.

A restrictor plate is shown in Figure 5 at 168 at one side of the seat assembly and a corresponding restrictor plate 170 is located at the opposite side of the seat assembly. Restrictor plate 168 and restrictor plate 170 are pivoted on the cross-rod 112. Thus, both restrictor plates and both parallelogram linkage elements 106 and 108 pivot about a common axis. The upper end of the elements 106 and 166 are pivotally connected to the lower seat portion side frame members 90 and 92, respectively. As indicated previously, the restrictor plates 168 and 170 also are pinned to the frame side members 90 and 92. The pivot pin at the upper ends of the linkage elements 106 and 166 and the pin for the restrictor plates 1688 and 170 are common.

The frame side member 110 for the upright seat back portion has a semicircular frame extension 172 that corresponds to the frame extension 126. As seen in Figure 12, the extension 172 has a pair of openings through which a locking pin 174 is received. The pin 174 extends through an arcuate slot 176 formed in the restrictor plate 170.

A locking pin spring 178 surrounds the pin 174 and is disposed within the semicircular frame extension 172. Pin 174 is provided with a spring seat element 180 for biasing normally the pin 114 toward the base 102 ' .

As in the case of frame extension 126, the frame extension 172 has a cam surface shown at 182 which corresponds to the cam surface 128. This engages a roller that corresponds to the roller 130 described previously with reference to Figure 8. That roller is carried by a rod that is received by lower seat portion frame side member 62.

When the pin 174 is moved against the force of the spring 178, it disengages from the base 102'. This unlocks the frame for the seat back portion thereby permitting it to be folded forward. When the locking pin 174 is in the position shown in Figure 12, the seat back portion is relatively fixed with respect to lower seat portion frame 80.

A corresponding pin is received through an arcuate slot in the restrictor plate 168, through the frame extension 126 and through the base 102.

The pin 174 and the corresponding pin for the restrictor plate 168 can be pulled against the opposing force of the springs for the locking pins by cables 184 and 186, respectively. The cables are joined to an actuating lever 188, as seen in Figure 5. The lever 188 can be rotated in a counterclockwise direction to unlock the pins from their respective pin openings in the bases 102' and 102. When the actuating lever 188 is moved in a clockwise direction, the locking pin will snap into the locking position for the upright seat back portion under the influence of the springs for the locking pins.

When the locking pins are released, the seat back portion can be folded forward. This causes the lower seat portion to be shifted forward as indicated in Figure 10. Because of the parallelogram linkage established by the linkage elements 94 and 106 and by the parallelogram linkage elements 164 and 166, the lower seat portion will be folded downward as it shifted forward.

The parallelogram linkage established by the linkage elements 172 and 130 on one side of the seat back portion and by the linkage elements 136 and 134 on the opposite side of the seat back portion are held in their extended position shown in Figure 6 by a link 190. One end of the link 190 is pinned rotatably at 192 to the base 102. At its opposite end it is pinned at 162 to the end of link 132 at the lower region of the seat back portion.

The panel 138 together with the side member 118 of the frame 82 for the seat back portion form opposite sides of a parallelogram linkage as seen in Figure 6. As the frame 82 is pivoted about the axis of the rod end 110, the link 190 causes the parallelogram linkage elements 130 and 132 to pivot thereby folding the parallelogram linkage until it achieves the folded state indicated in Figure 10.

The link 190 can be formed as shown in Figure

5 so that interference with the frame side member 118 will not occur when the seat back portion 12 is folded forwardly.

The construction shown in Figures 10 and 10a is illustrated only schematically. The mounting structure for the base 102, for example, differs from the mounting structure illustrated in Figure 5. Figures 10 and 10a are intended merely to show the mode of operation of the foldable parallelogram linkages.

Figures 9 and 9a show cross-sectional representations of the frame member 90 for the lower seat portion. The link 94 of Figure 9 is shown also in Figure 11a. Frame member 90 has a foam rubber cushion 194, and a corresponding cushion is provided on the frame side member 92 of the lower seat portion. The outer margin of the frame member 90 is provided with a channel 196 in which is received the margin of the foam rubber cushion 194, thereby holding the latter securely in place.

An elastomer fabric 198 is stretched across the lower seat portion and is anchored in the frame side members 90 and 92 in the manner illustrated schematically in Figures 9 and 9a. The elastomer fabric is a woven fabric which yields under the weight of the passenger. A material that has been successfully used for this purpose is manufactured by Acme Mills Company of Detroit, Michigan under the trade name "DYMATROL" . The use of the elastomer fabric and the use of hollow frame members, which preferably are made of aluminum alloy, results in a very light weight seat assembly which reduces the weight of the vehicle. The reduced weight also makes it easier to assemble the seat assemblies and to carry the seat assemblies when they are removed from the vehicle.

When the seat back portion is folded forward as described previously, the springs that act on the rollers 130 at each side of the seat assembly cause the locking pin 174 to engage one end of the arcuate slot 176 and the corresponding slot for the restrictor plate 168. When the seat back portion has been moved through an arc of about 85° as it is folded forward to the position shown in Figure 10, the ends of the arcuate slots are engaged by their respective unlocking pins. Further movement in the forward folding direction can be achieved through an angle of about 15° as the pin 174 and the corresponding pin for the restrictor plate 138 move in the respective arcuate slots in the restrictor plates 170 and 168. This additional arcuate travel of the seat back portion is needed because the length of the arc traveled by the upper end of the link 190 exceeds the length of the arc traveled by the upper end of the parallelogram linkage element 106.

Figure 7 shows a tandem arrangement for the foldable seat assembly of the invention. The embodiment of Figure 7 functions in the same fashion as the embodiment of Figure 5 and the description of the mode of operation need not be repeated. For purposes of clarity, the reference numerals have been indicated in the embodiment of Figure 7 with prime notations in the case of the left-hand seat assembly and double prime notations in the case of the right-hand seat assembly. These numerals with prime notations or double prime notations correspond to the numerals designating similar structure in the embodiment of Figure 5.

Claims

What Is Claimed Is:

1. A seat mounted within a vehicle having a compartment that is converted between a passenger configuration and a cargo carrying configuration, the compartment having a floor that defines a recess and a right wheel housing and a left wheel housing on opposite sides of the floor, said seat comprising: a lower seat assembly having a front portion and a rear portion; a seat back assembly pivotally connected to the lower seat assembly; a right rail secured to the right wheel housing, said right rail defining a first channel; a left rail secured to the left wheel housing, said left rail defining a second channel; a right side shiftable element connected to the rear portion of the lower seat assembly and received in the first channel of the right rail for movement along the first channel; a left side shiftable element connected to the rear portion of the lower seat assembly and received in the second channel of the left rail for movement along the second channel ; a right link arm pivotally connected on an upper end to the front portion of the lower seat assembly and pivotally connected to the floor; a left link arm pivotally connected on an upper end to the front portion of the lower seat assembly and pivotally connected to the floor; a right locking pin associated with the right link arm that selectively locks the right link arm to the right rail; a left locking pin associated with the left link arm that selectively locks the left link arm to the left rail; said seat being converted from the passenger configuration to the cargo carrying configuration by pivoting the seat back assembly onto the lower seat assembly, disengaging right and left locking pins from the right and left rails, respectively, shifting the lower seat assembly forward by moving the right and left side shiftable elements forward in the first and second channels, respectively, and pivoting the upper ends of the right and left link arms forward and downward until the lower seat assembly is received in the recess formed in the floor of the vehicle.

2. The seat of claim 1 wherein said shiftable elements are rollers.

3. The seat of claim 1 wherein right and left rails have a series of holes spaced along a portion of their length, and said right and left locking pins being selectively received in corresponding holes in the right and left rails to permit adjustment of the position of the seat fore and aft .

4. The seat of claim 1 wherein the seat back assembly has a rear surface that is oriented in a substantially horizontal plane when the seat is in the cargo carrying configuration.

5. The seat of claim 1 wherein the right and left locking pins extend from the right and left link arms .

6. The seat of claim 1 further comprising an actuator connected to the right and left locking pins that is actuated to extend and retract the right and left locking pins.

7. A seat assembly with a lower seat portion and an upright seat back portion, the lower seat portion being supported on a base, said seat back portion being pivoted on said base; a foldable linkage mechanism supporting said lower seat portion on said base; said upright seat back portion being engage- able with said lower seat portion upon pivotal movement of said upright seat back portion to a stacked position over said lower seat portion whereby said lower seat portion is moved forwardly relative to said base; said foldable linkage being movable upon forward movement of said lower seat portion thereby lowering said lower seat assembly toward said base and reducing the overall stacked height of the seat assembly when it is in a folded state.

8. A seat assembly with a foldable lower seat portion and an upright foldable seat back portion supported on a base, said seat back portion being connected pivotally at its lower margin in said base near a rearward margin of said lower seat portion; at least one first linkage element connected at its upper end to a forward margin of said lower seat portion and at least one second linkage element connected at its upper end to said rearward margin of said lower seat portion, the lower ends of said first and second linkage elements being pivotally connected to said base; said first and second linkage elements defining forward and rearward sides of a parallelogram linkage mechanism; said seat back portion being engageable with said lower seat portion as it is pivoted forwardly over said lower seat portion, said linkage mechanism folding to a lowered position upon pivotal movement of said seat back portion thereby reducing the overall stacked height of the seat assembly when it is in a folded state.

9. The seat assembly as set forth in claim

8 wherein said lower seat assembly comprises a lower seat frame and said upright seat back portion comprises an upright seat frame, said upright seat frame being pivoted on said base adjacent the rearward margin of said lower seat frame.

10. The seat assembly as set forth in claim

9 wherein said lower seat frame comprises a yieldable roller assembly connected to said lower seat frame at said rearward lower seat frame margin, said roller assembly engaging a lower portion of said upright seat frame; said upright seat frame, upon pivotal movement thereof toward a forward folded position, displacing said spring assembly in a direction toward said forward margin of said lower seat frame.

11. The seat assembly as set forth in claim

10 including a restriction plate pivoted at a first pivot point on said base and pivoted at a second pivot point to said lower seat frame at the location of said upper end of said second linkage element; and a releasable lock element connecting said upright seat frame to said base and to said restriction plate whereby pivotal motion of said seat back frame and folding motion of said first and second linkage elements are controlled.

12. The seat assembly as set forth in claim 11 wherein said restrictor plate includes an arcuate slot, said releasable lock element extending through said slot whereby secondary pivotal, forward movement of said upright seat back portion relative to said base is accommodated following initial pivotal movement thereof to a predetermined angular position relative to said base.

13. A seat assembly with a lower seat portion and an upright seat back portion, the lower seat portion being supported on a base, said seat back portion being pivoted on said base; a first foldable linkage mechanism supporting said lower seat portion on said base; said upright seat back portion being engage- able with said lower seat portion upon pivotal movement of said upright seat back portion to a stacked position over said lower seat portion whereby said lower seat portion is moved forwardly relative to said base; said foldable linkage being movable upon forward movement of said lower seat portion thereby lowering said lower seat portion toward said base and reducing the overall stacked height of the seat assembly when it is in a folded state; said upright seat back portion including a back panel, a second foldable linkage mechanism connecting said upright seat back portion to said panel; an actuator link connected at one end thereof to said base and at the other end thereof to said second foldable linkage mechanism whereby pivotal forward movement of said upright seat back portion moves said second foldable linkage mechanism to a folded position.

14. The seat assembly as set forth in claim

8 wherein said upright seat back portion includes a back panel, a second foldable linkage mechanism connecting said upright seat back portion to said panel; and an actuator link connected at one end thereof to said base and at the other end thereof to said second foldable linkage mechanism whereby pivotal forward movement of said upright seat back portion moves said second foldable linkage mechanism to a folded position.

15. The seat assembly as set forth in claim

9 wherein said upright seat back portion includes a back panel, a second foldable linkage mechanism connecting said upright seat back portion to said panel; and an actuator link connected at one end thereof to said base and at the other end thereof to said second foldable linkage mechanism whereby pivotal forward movement of said upright seat back portion moves said second foldable linkage mechanism to a folded position.

16. The seat assembly as set forth in claim 10 wherein said upright seat back portion includes a back panel, a second foldable linkage mechanism connecting said upright seat back portion to said panel; and an actuator link connected at one end thereof to said base and at the other end thereof to said second foldable linkage mechanism whereby pivotal forward movement of said upright seat back portion moves said second foldable linkage mechanism to a folded position.

17. The seat assembly as set forth in claim

11 wherein said upright seat back portion includes a back panel, a second foldable linkage mechanism connecting said upright seat back portion to said panel; and an actuator link connected at one end thereof to said base and at the other end thereof to said second foldable linkage mechanism whereby pivotal forward movement of said upright seat back portion moves said second foldable linkage mechanism to a folded position.

18. The seat assembly as set forth in claim

12 wherein said upright seat back portion includes a back panel, a second foldable linkage mechanism connect- ing said upright seat back portion to said panel; and an actuator link connected at one end thereof to said base and at the other end thereof to said second foldable linkage mechanism whereby pivotal forward movement of said upright seat back portion moves said second foldable linkage mechanism to a folded position.

19. A seat mounted within a vehicle having a compartment that is converted between a passenger configuration and a cargo carrying configuration, the compartment having a floor that defines a recess and a right wheel housing and a left wheel housing on opposite sides of the floor, said seat comprising: a lower seat assembly having a front portion and a rear portion; a seat back assembly pivotally connected to the lower seat assembly; a right rail secured to the right wheel housing, said right rail defining a first channel; a left rail secured to the left wheel housing, said left rail defining a second channel; a right side shiftable element connected to the rear portion of the lower seat assembly and received in the first channel of the right rail for movement along the first channel; a left side shiftable element connected to the rear portion of the lower seat assembly and received in the second channel of the left rail for movement along the second channel ; a right link arm pivotally connected on an upper end to the front portion of the lower seat assem- bly and pivotally connected to the floor; a left link arm pivotally connected on an upper end to the front portion of the lower seat assembly and pivotally connected to the floor; a right locking pin associated with the right link arm that selectively locks the right link arm to the right rail; a left locking pin associated with the left link arm that selectively locks the left link arm to the left rail; said seat being converted from the passenger configuration to the cargo carrying configuration by pivoting the seat back assembly onto the lower seat assembly, disengaging right and left locking pins from the right and left rails, respectively, shifting the lower seat assembly forward by moving the right and left side shiftable elements forward in the first and second channels, respectively, and pivoting the upper ends of the right and left link arms forward and downward until the lower seat assembly is received in the recess formed in the floor of the vehicle; a foldable linkage supporting said lower seat assembly on said floor; said seat back assembly being engageable with said lower seat assembly upon pivotal movement of said seat back assembly to a stacked position over said lower seat assembly whereby said lower seat assembly is moved forwardly relative to said base; said foldable linkage being movable upon forward movement of said lower seat assembly thereby lowering said lower seat assembly toward said floor and reducing the overall stacked height of the seat when it is in a folded state.