WO2005102112A2

WO2005102112A2 - Adjustable height vehicle seat bottom

Info

Publication number: WO2005102112A2
Application number: PCT/US2005/013042
Authority: WO
Inventors: Thomas P. Woellert; Larry E. Gray; Jeffrey D. Huck
Original assignee: Indiana Mills & Manufacturing, Inc.
Priority date: 2004-04-15
Filing date: 2005-04-15
Publication date: 2005-11-03
Also published as: WO2005102112A3

Abstract

A vehicle seat (10) that has a seat support assembly (15) that is adjustable in height relative to a base assembly (30) which is coupled to the seat support assembly (15) by one or more linkage assemblies (11). The linkage assemblies (11) comprise a pair of link members (20, 25) movably connected in crossing relationship and are urged toward an extended position by a bias member (35) acting between the link members (20, 25).

Description

ADJUSTABLE HEIGHT VEHICLE SEAT BOTTOM

Cross-Reference to :

[0001] This application claims priority to and the benefit of U.S. Provisional

Application No. 60/562,938, the disclosure of which is now incorporated herein by reference.

Field Of The Invention:

[0002] This disclosure relates to passenger restraint systems for use in vehicles, and more particularly, to an adjustable vehicle seat bottom.

BACKGROUND OF THE INVENTION [0003] Conventional integral vehicle passenger restraint or seat belt systems combining a lap belt and an upper torso belt are well known. These three-point restraint systems are usually used with seats offering rigid support for the belts. As typically used in a vehicle, the integral three-point restraint system consists of a single belt having its opposite ends mounted to a pair of retractors with a seat belt tongue connected to the belt intermediate to the belt ends. The tongue may be swung across the person and engaged with a buckle affixed to the seat thereby positioning one portion of the belt across the lap and another portion of the belt across the upper torso. In some systems, only one end of the belt is mounted to a retractor while the other end is anchored to the seat or vehicle. Seat belts are active restraint devices, requiring a passenger to actively engage the restraints for them to be effective. However, smaller passengers, such as children, toddlers and infants, and special needs passengers may not be able to use the seat belt systems found on vehicles. Rather, they may need to use one of various add-on restraint systems such as for example, torso harnesses, positioning harnesses, portable child seats and booster seats.

[0004] Generally, such harnesses and portable child seats are securely attached to the vehicle seat, with the harnesses and child seats having their own restraint systems for the passenger, thereby obviating the need to resort to the vehicle's three-point seat belt system. To attach such add-on restraint systems, the federal government has mandated that child restraint anchorage systems be installed in most vehicles, including cars, trucks, vans, sports utility vehicles (SUVs) and certain school buses. These regulations, popularly known as LATCH, are codified at 49 C.F.R. § 571.225 (FMVSS 225), incorporated herein by reference, require two lower anchorages and an upper tether anchorage of specified configuration, location and strength parameters. Similarly, 49 C.F.R. § 571.213 (FMVSS 213), incorporated herein by reference, specifies the dimensions of tether hooks used to attach a tether strap to a tether anchorage. However, booster seats, which may accommodate passengers weighing from about 30 pounds to about 110 pounds, are used in combination with the vehicle's seat belt system. Booster seats raise the sitting height of a passenger who is too large for a child seat, but otherwise too short for the vehicle's seat belt system. This allows the passenger to use the vehicle's integrated seat belt system without the shoulder belt of the seat belt system falling in an uncomfortable or unsafe position, such as the throat, of the passenger. These booster seats may use one or more of the lower and upper LATCH anchorages, alone or in combination with the vehicle's seat belt system, or may use the vehicle's seat belt system alone to secure the booster seat to the vehicle. Examples of booster seats are disclosed in U.S. Pat. Nos. 5,797,654 to Stroud, 5,829,834 to Silverman, and 5,685,604 to Kain, which are incorporated by reference herein.

[0005] While there are some school buses that have LATCH anchorages, there are pre-existing seats in school buses that do not have LATCH and do not have active restraint systems of any kind, or which might benefit from additional restraint systems of some kind. School bus passenger seats usually do not employ active restraint safety devices, but instead rely on a passive restraint seat design. School bus passenger seats are built to specifications conforming to the safety standards set by the National Highway Traffic Safety Administration, Department Of Transportation (DOT). These are codified as 49 C.F.R. Ch.V, § 571.222, Standard No. 222 (Federal Motor Vehicle Safety Standard (FMVSS) 222), and require that the seat back bend or deflect forward when a force is applied to the rear of the seat back. The code specifies a passive restraint system, and does not require any sort of active restraints, such as a two-point passenger restraining lap belt or a three- point passenger restraining lap belt and torso harness combination. Passengers riding the school bus are protected in head-on collisions by the seat back in front of them deflecting forward and absorbing some of their forward momentum.

[0006] Further passenger protection, from head-on and non-head-on collisions and roll events, may be provided by active restraint systems. One such active restraint system might be a lap belt restraint. Vehicles, such as buses, which require the passive protection deforming or deflecting seats provide, present certain challenges regarding the integration of active restraint seat belt systems. In a school bus seat combining active and passive restraint systems, both of the restraint systems may need to be able to perform their functions and the seat may still need to conform to the regulations set forth in FMVSS 222, which is incorporated herein by reference. In addition to two-point active lap restraint systems, examples of vehicle seats designed to combine both active and passive restraint systems in conformity with FMVSS 222 are found in commonly owned U.S. Patent No. 6,485,098, and U.S. Patent application No. 10/245,983, the disclosures of which are now incorporated herein by reference. Two-point lap belt systems, or these new three-point lap belt systems may allow the use on buses of various add-on restraint systems such as torso harnesses, positioning harnesses, portable child seats and booster seats. Commonly owned U.S. Patent Application No. 10/245,983, incorporated herein by reference, discloses supplemental restraint systems for use with a school bus seat in accordance with FMVSS 222.

[0007] Disclosed herein is an adjustable height vehicle seat that functions both as a regular vehicle seat and a booster seat, thereby allowing adult-size passengers and some smaller passengers to use the vehicle's integral passenger restraint or seat belt system without the need to use an add-on or portable booster seat. The disclosed seat may, but need not be compatible with FMVSS 222 and FMVSS 225, and may be retrofitted to existing vehicle seats. SUMMARY OF THE INVENTION

[0008] The present invention may comprise one or more of the following features and combinations thereof. An adjustable height vehicle seat is provided. The adjustable height vehicle seat generally comprises: a base assembly; a seat support assembly, at least one linkage assembly including a first link member and a second link member movably associated with one another in crossing relationship and disposed between and movably connected to the seat support assembly and to the base assembly; and a bias member acting between the first link member and the second link member, the bias member tending to urge apart the seat support assembly and the base assembly. A pivot member may movably associate together the first link member and the second link member. One of the link members may be fixed against movement relative to the pivot member and the other of the link members may be movable relative to the pivot member. An actuation assembly may be coupled to the base assembly and may generally comprise an actuating member coupled to a locking pin. The locking pin may cooperate with the base to lock the seat support assembly in a retracted or stowed position and a deployed or extended position or positions. The locking pin may define a slot that locks the pin to the base when the seat support assembly is in a deployed position and a force is applied to the seat support assembly in the direction of the base or floor. The actuation assembly allows the seat support assembly to be moved between stowed and deployed positions in order to adjust the height of the seat support assembly relative to the vehicle floor. By adjusting the height of the seat support assembly above the floor, a passenger of insufficient stature to use the vehicle's integral seat belt or passenger restraint system, may be raised a sufficient amount to allow the integral seat belt system to properly fit and restrain the passenger. Therefore, the adjustable height seat serves as a regular vehicle seat in the stowed position that can be used as a booster seat in the deployed position or positions without the need for an addon booster seat that must be attached to the vehicle seat using belts, straps, anchorages and the like. The disclosed adjustable height vehicle seat may be retrofitted to existing vehicle seats and it may but need not be compatible with FMVSS 225 thereby accommodating add-on child restrain systems known in the art. The variable height vehicle seat may be used in such vehicles as cars, school buses, tour buses, vans, SUVs, recreational vehicles (RVs), air planes, watercraft, and other vehicles or modes of conveyance, such as for example ski lifts, without limitation. The seat may be configured for use with the existing restraint systems of these vehicles in lieu of or in combination with any add-on restraint systems such as positioning harnesses, child seats or booster seats. So too, any such restraint systems, whether integral to the vehicle or whether an add-on system, may be used in lieu of the current invention without any interference from the current invention.

[0009] Also provided is a method of restraining a passenger in a vehicle generally comprising the steps of: providing an adjustable height vehicle seat comprising a seat support assembly movably connected to the vehicle floor by a linkage assembly pair including a first link member and a second link member movably associated with one another in crossing relationship, and a bias member acting between the first link member and the second link member, the bias member tending to urge the seat support assembly away from the floor; and adjusting the height of the vehicle seat above the floor to allow a passenger supported by the seat support assembly to properly don a passenger restraint system integral to the vehicle.

[0010] Additional features will become apparent to those skilled in the art upon consideration of the following detailed description of illustrative embodiments and claims exemplifying the best mode of carrying out the invention as presently perceived.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] FIG. 1 is a perspective view of an illustrative adjustable height seat in the normal stowed or lowered position.

[0012] FIG. 2 is a perspective view of the illustrative adjustable height seat of

FIG. 1 shown in the raised or actuated position.

[0013] FIG. 3 is a bottom perspective view of the illustrative adjustable height seat of FIG. 2. [0014] FIG. 4 is a cross-sectional view taken generally along the line 4-4 in

FIG. 2.

DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENTS

[0015] For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.

[0016] The drawings depict illustrative embodiments, which will be described now in detail. Referring to FIGs. 1-3, an illustrative embodiment of the adjustable height vehicle seat 10 is depicted. The illustrative adjustable height vehicle seat 10 comprises generally a seat support assembly 15, a base assembly 40, and one or more linkage assemblies 11 each having an inner or first link member 20, and an outer or second link member 25. The illustrative adjustable height vehicle seat 10 may further comprise an actuation assembly 45. The adjustable height vehicle seat 10 is configured for use with a vehicle seat (not shown) comprising a generally vertically extending back portion (not shown) and a generally horizontally extending seat portion. The back portion or seat back (not shown) and the seat portion (not shown) converge and meet in an area generally known as the bight. It will be appreciated that further locking apertures could be provided between apertures 36 and 39 in order to facilitate varying height adjustments or deployment displacement distances, and that fewer locking apertures could also be provided if alternate means of locking or biasing the seat support assembly 15 were used as will be explained. The vehicle seat may be any conventional vehicle seat found in for example a bus, a van, a truck, an SUV, an RV, a watercraft, or an aircraft. The seat is configured to accommodate a passenger weighing up to about 110 pounds (50 kg) when the seat is in the extended or deployed position or positions best depicted generally in FIG. 2. - 1 ^■

[0017] The seat support assembly 15 generally and illustratively comprises a generally horizontal seat support member 16 extending transversely between a pair of upstanding side surfaces 18, 19. The side surfaces 18, 19 may be integral with the seat support member 16, or may be separate pieces attached to the seat support member 16. Each of the side surfaces 18, 19 defines a generally elongate guide or channel 32, having opposing ends 32A and 32B. The seat support member 16 may support a cushion or squab upon which a passenger rests, and illustratively has at its back end a cutout 14, which, along with the base assembly 40, is configured to accommodate the structure of a vehicle's existing passenger seat. Such a seat, for example, may include a folding or stow-and-go seat that folds into the floor and is found in various vans, mini-vans, trucks and SUVs. Of course, the seat 10 may be provided as original equipment. The seat support member 16 may, but need not be contoured 13 in any desired way.

[0018] Illustratively, the base assembly 40 comprises a pair of spaced apart and generally parallel side, base or frame members 30 configured to mount to a vehicle using for example any suitable fastener received by apertures 50 formed in embossments 34. Each side member 30 defines a generally elongate guide or channel 31 , having opposing ends 31 A and 31 B, and an ear or tab 57.

[0019] The seat support assembly 15 and the base assembly 40 illustratively are interconnected in generally parallel and spaced relationship to one another by the one or more linkage assembly pairs 11. In each linkage assembly 11 , the pair of link members 20, 25 are movably associated, coupled or connected to one another in crossing relationship by a pivot member 22, such as for example and without limitation a pin, spindle, shaft, bolt or other suitable connector. One end of each first link member 20 is movably but non-slidably connected to base side member 30 through a connector 26, while the other end of each first link member 20 is pivotally and displaceably or slidably mounted in guide or channel 31 of base side member 30 through connector 21. One end of each second link member is movably but non- slidably connected to seat support assembly 15 through a connector 24, while the other end of each second link member 25 is pivotally and displaceably or slidably mounted in guide or channel 32 of seat support member 15 through connector 23. The pair of spaced apart linkage assembly pairs 11 illustratively are connected by a transverse member 41 , which, among other things generally ensures concert of movement. For example, if one side of the seat support assembly 15 is pushed down, then both sides will move downwardly generally in unison. In addition, the transverse member 41 may provide lateral support so that the scissor mechanisms 11 do not spread or bow outwardly. Illustratively, the pivot member 22 has formed through one end a slot 56, configured to receive therein one end of bias member 35. Illustratively, the bias member 35 is a power spring or torsion spring. The other end of bias member 35 engages and applies a force between the link members 20, 25. For example, the bias member 35 may be mounted on one of the link members, illustratively first link member 20, and apply a force to the other of the link members, illustratively second link member 25. Illustratively, the force is applied through a protrusion 55 formed on the link member 25. The first link member 20 is generally fixed from movement relative to pivot member 22, the second link member is movable relative to the pivot member 22. Connectors 21, 27 also movably connect to each base member 30 a pawl 28. Pawl 28 defines an appendage or extension 29 configured to movably receive connector 21 , a locking aperture 36, a locking aperture 39, and a channel 33 having opposing ends 33A and 33B and configured to movably receive connector 27.

[0020] Other configurations fall within the scope of the invention. For example, it would be possible to reverse the arrangement of the link members 20, 25 and the bias member 35 in any desirable way. For example and without limitation, suitable arrangements include any one or more of the following: the first link member 20 could be disposed outside the second link member 25, the bias member 35 could apply a force against the inner link member, the outer link member could be fixed from movement relative to the pivot member 22, pawl 28 could be on the inside of base side member 30, and the inner link member could be slidable relative to the base side member 30 and non-slidable relative to the seat support assembly 15, while the outer link member could be slidable relative to the seat support assembly 15 and non-slidable relative to the base side member 30. Also, while the pair of linkage assembly pairs illustratively are spaced apart in generally parallel relationship, they could be disposed in a generally perpendicular relationship, which would require one or more additional base side member(s) 30 disposed perpendicular to the depicted side members 30, such that one linkage assembly pair is disposed on the side and one is disposed on the front or back of the seat 10. So too, a third and/or fourth linkage assembly pair could be added to the front and/or rear of the seat 10 for use with the two parallel linkage assembly pairs 11 depicted in the Figures. It will be appreciated that other height adjusting arrangements, such as a telescoping arrangement could be used. Those skilled in the art will also realize that the base assembly 40 could be eliminated if the vehicle floor was configured to operatively mount the linkage assembly 11.

[0021] The actuation assembly 45 generally comprises one or more release or locking pins 37 operatively coupled or connected to respective actuating members 43. Illustratively, as best seen in FIG. 3, the illustrative embodiment has a pair of locking pins 37 operatively coupled to respective actuating members 43. One example of a suitable actuating member includes a cable. The actuating members 43 are attached to handle 44, such as for example a D-ring, which in turn may but need not be attached to another member such as for example a rope, cable, tab, or web 49. It will be appreciated that the D-ring 44 could be replaced by other suitable devices such as for example a switch, a button, a lever, and the like without limitation and may be associated with any suitable mechanical or electrical control circuitry and logic. A bracket 48 illustratively mounts the handle 44 to the vehicle by connecters received through apertures 51 formed in the bracket 48. A bias member or spring 47 tends to urge the locking pins 37 into locking engagement with one of the locking apertures 36, 39, which are configured to receive the locking pin(s) 37. Housing 46 partially surrounds bias member 47. A bracket 58 connected to each housing 46 illustratively has ears 59 which connect the housing to ear or tab 57. Each locking pin 37 defines a locking groove or slot 38 through at least a portion of its periphery.

[0022] The seat components may be fashioned out of any suitable metallic, non-metallic or composite material or combination thereof and may be manufactured using any process suitable to the material being used. In the illustrative embodiment, the base assembly 40 is but need not be made out of high-strength, low-alloy steel, through stamping, injection molding, or screw molding and the seat support assembly 15 illustratively is but need not be made from glass filled nylon. Illustratively, the seat support assembly may range from about nine (about 228 mm) to about sixteen inches (about 407 mm) from front to back (length) and from about fifteen (about 380 mm) to twenty inches (about 508 mm) from side to side (width). While the seat support assembly 15 in the retracted or stowed position will support the weight of most any passenger, it illustratively may in the raised or deployed position(s) support a passenger weighing up to about 110 pounds (about 50 kg). The amount of displacement between the base assembly 40 and the seat support assembly 15, from the normally retracted or stowed position, which is generally proximate to the base assembly 40 and floor, to the fully raised or deployed position ranges from about four (about 100 mm) to about six inches (about 155 mm). This fully deployed position will accommodate passengers ranging in height from about 38 inches (about 965 mm) to about 60 inches (about 1524 mm). As noted below, intermediate deployed heights or positions may be provided.

[0023] In operation, the seat support assembly 15 is normally in the retracted or stowed position, which accommodates most any passenger, to include those using any type of add-on restraint system, including a strap-on or LATCH compatible booster seat. In order to accommodate, without using an add-on booster seat, a passenger that does not have the stature to use the vehicle's integral passenger restraint or seat belt system, the height of the seat support assembly 15 above the floor of the vehicle may be adjusted by displacing or deploying the seat support assembly 15 away from the base assembly and vehicle floor. To deploy the seat support assembly 15, a user applies a force, as by pulling, to the web 49 in order to actuate the actuating member(s) 43 to overcome the force of the bias member(s) 47 and withdraw the locking pin(s) 37 from the locking aperture 36. When the locking pin(s) clear the pawl 28, the tension on the bias member or spring 35 applies a force to the linkage assembly pair(s) 11 to urge or cause the seat support assembly 15 to displace apart or away from the base support assembly 40, and the floor of the vehicle in which the seat is mounted, generally in parallel into the deployed or extended position(s). As the bias member(s) 35 act between the link members 20, 25 to deploy or displace the seat support assembly 15, the interconnected nature of the linkage assembly pairs 11 , the seat support assembly 15, base assembly 40, and the pawl 28, causes the respective ends of each of the link members 20, 25 near simultaneously to move non-slidably about respective connectors 24, 26, to move, and displace or slide within respective channels 31, 32 from one end 31 B, 32B to the other end 31 A, 32A., and further causes the pawl to displace an amount equal to the length of channels 31 , 33 from 31 B, 33B to 31 A, 33A. As the pawl reaches the end of the channels 31 , 33, the seat support assembly 15 reaches the fully extended or deployed position and the respective locking pin(s) 37 are aligned with respective locking aperture(s) 39. Releasing the web 49 allows the bias member(s) 47 to urge the locking pin(s) 37 into engagement with the locking aperture(s) in the pawl 28 thus generally locking the seat support assembly 15 in the deployed position. The seat support assembly 15 may be redeployed or displaced to the retracted or stowed position by pulling on the web 49 to overcome the force of the bias member(s) 47 and withdraw the locking pin(s) 37 from the locking aperture(s) 39 and applying to the seat support assembly 15 a force toward the base assembly 40. However, as best seen in FIG. 4, the elongate nature of the locking aperture(s) 39, illustratively a D-shape as seen in FIG. 1 , allows the locking pin(s) 37 to move somewhat within the aperture(s) 39. Thus, when any force is applied to the seat support assembly 15 towards the base assembly 40, the linkage assemblies 11 will displace somewhat, thereby moving the pawl from 33A toward 33B until such displacement is halted by the engagement or seating of the pawl 28 with the slot 38 formed in the locking pin 37 as best seen in FIG. 4. The described engagement of the pawl 28 and the locking slot 38 locks the locking pin 37 within the locking aperture 39, such that the locking pin 37 cannot be removed or withdrawn from the aperture 39 until the force is removed from the seat support assembly 15. Therefore, pulling on the web when a force is also applied to the seat support assembly 15 in opposition to the force exerted by the bias member(s) 35, such as that produced by the weight of a passenger sitting on the seat, would not result in the release pins 37 being withdrawn from the pawl 28 because the force applied to the seat support assembly 15 has seated the pawl 28 within the slot or groove 38. Therefore, the seat support assembly 15 may not be displaced or redeployed to its normal or retracted position if a passenger is being supported by the seat. Once the locking pin(s) 37 are disengaged from the pawl 28, a force may be applied to the seat opposite the force exerted by the bias member(s) 35 in order to displace or move the seat support assembly 15 towards the base assembly 40 until the locking pin(s) 37 are aligned with locking aperture 36. The actuating members 43 may then be released so that the bias member(s) 47 can urge the locking pin(s) 37 to engage the locking aperture 36 and generally fix the pawl 28, interconnected linkage assemblies 11 and seat support assembly 15 from movement.

[0024] It will be appreciated that further locking apertures could be provided between apertures 36 and 39 in order to allow varying displacement distances, or variable adjustments to the height of the seat support assembly, and that fewer locking apertures could also be provided if alternate means of locking or biasing the seat support assembly 15 were used. For example, those skilled in the art will appreciate that the bias member(s) 35 could be configured to tend to urge the seat support assembly 15 in the stowed or retracted position. In such a case, some other means, such as a force being applied to the seat support assembly manually by a person may be used to displace the seat support assembly 15 away from the base assembly 40 and into the deployed position. In such a case, only one locking aperture might be necessary. In addition, other means of locking the seat support may be used, eliminating the need for one or more of the locking apertures. So too, whether two, three, four or more linkage assemblies 11 are used, only one need be biased by bias member 35 and only one need have an associated pawl 28 and locking pin 37.

[0025] Illustratively, the seat support assembly 15 is configured to support a conventional seat bottom, such as an upholstered cushion found in vehicles. The adjustable height vehicle seat bottom 10 with a seat cushion would allow a passenger of the vehicle to use the vehicle's integral restraint system even if that passenger is not of the proper height to use the vehicle's integral restraint system when sitting directly on the vehicle's seat, or even when sitting on a booster seat or other add-on device. By raising the seat as just described, the passenger may be properly positioned to use the vehicle's integral restraint system. The adjustable height vehicle seat 10 may be used alone or in combination any other add-on device. For example, the adjustable height vehicle seat bottom 10 could be fully deployed, raised or elevated and then an add-on booster seat could be mounted to the seat cushion to better position a passenger if necessary. So too, a booster seat or portable child seat could mounted to the seat 10 and used in the retracted position. The seat 10 may, but need not be, fully compatible with LATCH standards found in FMVSS 225 and may be retrofitted to existing vehicle seats.

[0026] While the invention has been illustrated and described in detail in the foregoing drawings and description, the same is to be considered as illustrative and not restrictive in character, it being understood that only illustrative embodiments thereof have been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected.

Claims

What is claimed is:

1. An adjustable height vehicle seat comprising: a base assembly; a seat support assembly, a first linkage assembly pair including a first link member and a second link member movably associated with one another in crossing relationship and disposed between and movably connected to the seat support assembly and to the base assembly; and a bias member acting between the first link member and the second link member, the bias member tending to urge apart the seat support assembly and the base assembly.

2. The adjustable height vehicle seat of claim 1 further comprising a second linkage assembly pair including first and second link members spaced apart from the first linkage assembly pair, the first and second link members of the second linkage assembly pair movably associated with one another in crossing relationship and disposed between and movably connected to the seat support assembly and to the base assembly.

3. The adjustable height vehicle seat of claim 2 further comprising a second bias member acting between the first and second link members of the second linkage assembly pair.

4. The adjustable height vehicle seat of claim 1 or claim 3 wherein the bias member comprises a torsion spring.

5. The adjustable height vehicle seat of any one of claims 1 to 4 further comprising a pivot member movably associating together each respective first link member and second link member, one of the link members being fixed against movement relative to the pivot member and the other of the link members being movable relative to the pivot member.

6. The adjustable height vehicle seat of claim 5 wherein the pin defines a slot, wherein one end of the bias member is disposed in the slot and the other end of the bias member engages said other link member that is movable relative to the pivot member.

7. The adjustable height vehicle seat of claim 6 wherein said other end of the bias member engages a projection on said other link member.

8. The adjustable height vehicle seat of any one of claims 1 to 7 wherein each link member has first and second ends, the first end of each of the link member being connected slidably to one of the seat support assembly and the base assembly and the second end of each of the link members being non-slidably connected to the other of the seat support assembly and the base assembly.

9. The adjustable height vehicle seat of claim 8 wherein the first end of each first link member is slidably connected to the seat support assembly and the first end of each second link member is slidably connected to the base assembly.

10. The adjustable height vehicle seat of any one of claims 2 to 9 further comprising a transverse member extending between and connected to one of the link members of each of the linkage assembly pairs.

11. The adjustable height vehicle seat of claim 1 or claim 10 wherein the seat support assembly displaces from the floor of a vehicle in which the adjustable height vehicle seat is mounted substantially in parallelism relative to the floor.

12. The adjustable height vehicle seat of claim 11 wherein the adjustable height vehicle seat has a normally retracted position wherein the seat support assembly is disposed proximate to the base assembly and a deployed position wherein the seat support assembly is displaced away from the base assembly.

13. The adjustable height vehicle seat of claim 12 wherein the base assembly comprises a pair of spaced apart frame members.

14. The adjustable height vehicle seat of claim 13 wherein the adjustable height vehicle seat is configured to be retrofitted onto a vehicle having an existing seat structure.

15. The adjustable height vehicle seat of claim 14 further comprising an actuation assembly including at least one actuating member coupled to at least one locking pin, the locking pin operable to generally lock the seat support assembly in either the retracted position or the deployed position.

16. The adjustable height vehicle seat of claim 15 further comprising at least one pawl movably connected to the base assembly, the at least one pawl defining at least one locking aperture configured to receive the at least one locking pin.

17. The adjustable height vehicle seat of claim 16 further comprising a second pawl movably connected to the base assembly, and a second actuating member coupled to a second locking pin, the second pawl defining a second at least one locking aperture configured to receive the second locking pin.

18. The adjustable height vehicle seat of claim 17 wherein each of said locking pins defines a respective slot configured to engage the respective pawl to lock the locking pin within its respective at least one locking aperture.

19. The adjustable height vehicle seat of claim 18 wherein the actuation assembly is operable to vary the displacement distance of the seat support assembly relative to the base assembly.

20. The adjustable height vehicle seat of claim 19 wherein a passenger using the adjustable height vehicle seat may use a seat restraint system integral to the vehicle in which the adjustable height vehicle seat is mounted.

21. The adjustable height vehicle seat of claim 20, wherein the adjustable height vehicle seat complies with applicable regulations.

22. The adjustable height vehicle seat of claim 21 wherein the applicable regulations comprise FMVSS 225.

23. A method of restraining a passenger in a vehicle comprising the steps of: providing an adjustable height vehicle seat comprising a seat support assembly movably connected to the vehicle floor by a linkage assembly pair including a first link member and a second link member movably associated with one another in crossing relationship, and a bias member acting between the first link member and the second link member, the bias member tending to urge the seat support assembly away from the floor; and adjusting the height of the vehicle seat above the floor to allow a passenger supported by the seat support assembly to properly don a passenger restraint system integral to the vehicle.