GB2298130A

GB2298130A - An adjustable seat assembly for a vehicle

Info

Publication number: GB2298130A
Application number: GB9502949A
Authority: GB
Inventors: Christopher John Lord
Original assignee: ELAP ENG Ltd
Current assignee: ELAP ENG Ltd
Priority date: 1995-02-15
Filing date: 1995-02-15
Publication date: 1996-08-28
Also published as: GB9502949D0

Abstract

An adjustable seat assembly for a vehicle to facilitate entry and exit from a vehicle comprising upper 12, intermediate 14, and lower 16 support means whereby the upper support means has a seat 10 mounted thereon and is pivotally mounted on the intermediate support means for movement about a substantially vertical axis, the intermediate support means being pivotally mounted by at least two linkage arms 41, 42, (43, 44) to the lower support means so as to allow raising and lowering of the seat relative to the lower support means, and an actuator 52 pivotally connected to the linkage arms or to the intermediate support so as to raise or lower the seat relative to the lower support means by swinging the linkage arms into a raised or a collapsed condition.

Description

An Adjustable Seat Assemblv for a Vehicle This invention relates to an adjustable seat assembly for a vehicle and to a vehicle having such an assembly installed therein.

It is extremely difficult for an aged, handicapped or invalid person to enter or leave a vehicle which is fitted with conventional vehicle seats which are only capable of positional adjustment in a direction parallel to the longitudinal axis of the vehicle. This is mainly because it is necessary for a person riding in such a seat to swing their body and legs around on the seat from a normal position in line with the longitudinal axis of the vehicle to a position where their legs extend through an open door in order to leave the vehicle, and to swing their body and legs around in the opposite direction when entering the vehicle.

Such a swinging movement of the legs is very difficult or even impossible for an aged, handicapped or invalid person to accomplish.

To overcome the above problem, the applicants have previously proposed, in their earlier patent GB 1 426 428, an adjustable seat assembly wherein a support frame, to which the seat is secured, is pivotally connected to the vehicle body for movement about a vertical axis, so that the seat can be rotated to a position where its front edge projects beyond the vehicle door sill. In this respect, the pivot axis is eccentric of the seat and more specifically is below the outer rear quadrant of the seat.

An additional problem for aged, handicapped and invalid persons is that the height of the vehicle seat in the case of high-silled vehicles is too high to allow for sitting down without troublesome or indeed painful stretching of the body trunk, with a comparable problem in reverse when trying to get out of the vehicle.

The seat assembly disclosed in the applicants prior patent included means enabling some measure of vertical adjustment of the seat relative to the vehicle body. However, this has proved to be inadequate to deal with the exceedingly high normal seat level in high-silled vehicles which are nowadays so popular.

An object of the present invention is to provide an improved design of adjustable seat assembly, which is usable in standard motorcars, yet which is specifically designed with high-silled vehicles in mind by allowing for much greater vertical adjustment of the seat than was possible.

In its broadest aspect, the present invention provides an adjustable seat assembly for a vehicle comprising upper support means having a seat mounted thereon, intermediate support means and lower support means, the upper support means being pivotally mounted upon the intermediate support means for movement about a substantially vertical axis and the intermediate support means being connected to the lower support means by way of at least two linkage arms which are pivotally connected at or near their respective ends to the intermediate and lower support means, respectively, and an actuator pivotally connected to the linkage arms or to the intermediate support means so as to raise and lower the seat relative to the lower support means by swinging the linkage arms into a raised condition and into a collapsed condition, respectively.

Naturally, the invention encompasses a vehicle having installed therein an adjustable seat assembly of the aforesaid type.

However, the lower support means may be omitted so that according to a second aspect of the present invention a vehicle may have an adjustable seat assembly comprising a first support pivotally mounted above a second support frame for movement about a substantially vertical axis, the second support frame being connected so the vehicle body by way of at least two linkage arms which are pivotally connected at or near their respective ends to the second support frame and to the vehicle body, or to elements mounted in or on said body, and an actuator pivotally connected to the linkage arms or to the intermediate support means so as to raise and lower the seat relative to the vehicle body by swinging the linkage arms into a raised and into a collapsed condition respectively.

The actuator is preferably in the form of a power-driven ram.

The actuator may conveniently be connected to a lever arm which is connected to a transverse member extending between two linkage arms, in which respect the lever arm projects laterally relative to the longitudinal axis of the linkage arms.

In another arrangement, the actuator can be connected directly to the intermediate support means.

The linkage arms are preferably four in number, two at each side of the seat.

Also the linkage arms preferably extend substantially parallel to each other.

The seat assembly is preferably arranged so that the vehicle seat can be raised a distance of, for example, 3.0 times the height of the collapsed seat assembly, though this height factor can lie in the range of 2.5 to 5.0.

When the assembly of the invention is used in a standard type of motor car which is relatively low silled the normal condition of the assembly will be the lowered condition, and it will be raised (and the seat rotated) for getting in and out. Conversely, when the assembly of the invention is used in a high-silled e.g four wheel drive vehicle, the normal condition of the assembly will be the raised condition, and it will be lowered (and the seat rotated) for getting in and out.

A particularly advantageous preferred feature of the seat assembly of the invention is that the linkage arms should extend obliquely in the same direction in both the raised and lowered (collapsed) conditions of the assembly.

However, the linkage arms could extend substantially vertically in the raised position if desired. Also, they could extend obliquely in the raised condition in a direction opposite to that in the lowered condition, although this would require overcentre movement of the arms during the operation of raising and lowering the seat.

Generally, a seat assembly according to the invention will be installed in a vehicle such that the linkage arms extend obliquely upwards from the vehicle floor (or the lower support means which is mounted thereon) in a direction towards the front of the vehicle so that upon the arms (and hence the seat) being raised the seat inevitably also moves towards the rear of the vehicle thereby increasing the leg room for any passenger on that seat, which may be particularly useful in facilitating access to that seat.

However, an alternative arrangement is envisaged wherein the seat assembly might be installed with the linkage arms extending obliquely upwards from the vehicle floor (or lower support means) in a direction away from the longitudinal central axis of the vehicle. With this arrangement the normal condition of the assembly, for travel in the vehicle, would be the raised condition and upon lowering of the linkage arms the seat would inevitably move outwardly of the vehicle as well as being lowered (as opposed to moving forwardly upon lowering in the standard arrangement). This alternative may prove particularly appropriate for use in high silled, e.g four wheel drive vehicles, where, as mentioned, the normal condition of the assembly will be the raised condition and lowering will be necessary for access when getting in and out of the vehicle.

The pivoting of the upper or first support relative to the intermediate or second support preferably takes place about an eccentrically vertical axis, which is located below the rear outer quadrant of the seat (as in the applicants earlier GB 1 426 428) so that the seat is able to rotate in a confined space without the rear corner of the seat adjacent the longitudinal central axis of the vehicle fouling obstacles such as centre consoles, prop shaft tunnels etc.

However the pivoting movement can take place about a centrally located vertical axis.

The seat is advantageously slidable relative to the upper or first support in a front to rear direction, for example by being mounted on slides which slidably engage tracks on the relevant support means. This allows the seat to be slid in the direction it is facing, and when the seat is rotated to face the door it can be substantially slid out from the vehicle.

Additionally, if required, the lower support means could be slidable relative to the vehicle body, in a longitudinal direction thereof, to allow independent longitudinal adjustment of the portion of the seat assembly.

With preferred embodiments of the invention the seat can be rotated and slid forwards at any vertical position of the assembly. This enables the seat to be at least partially projected from the vehicle door, and facing outwardly, at any desired height to best facilitate access.

The length of the linkage arms and their disposition relative to the intermediate support means and to the lower support means is advantageously such that the height of the sub-assembly comprising the intermediate and lower support means and the linkage arms in the raised condition of the assembly is at least 2.5 times the height of that sub-assembly in the collapsed condition of the assembly. Similarly, in cases where the linkage arms are mounted directly to the vehicle body the distance from said mounting to the top of the second support frame in the raised condition of the assembly may be over three times said distance in the collapsed condition of the assembly. In this respect most known vehicle seat lifting assemblies can only be raised through a height which is comparable with the height of the assembly in its lowest position.In other words only a doubling in height or thereabouts can be achieved.

In a preferred construction in accordance with the present invention there are four linkage arms which are of substantially equal length and which extend parallel to each other (thus providing a parallelogram linkage), with two arms at each side, that is to say a front and rear linkage arm at each side of the seat. The lever arm, to which the end of the ram is attached, is provided on a transverse member connecting the two front linkage arms and the geometry of the overall arrangement is chosen so that in the collapsed condition the lever arm clears the pivotal connection between the rear linkage arms, at that side and the intermediate (or second) support means. In this respect, a common pivot shaft preferably extends between the respective rear linkage arms. In the collapsed condition of the assembly, the lever arm preferably projects to the rear of said pivot shaft.

The invention will now be described further, by way of example, with reference to the accompanying drawings, in which; Figure 1 is a schematic side elevation, with parts detached, of a preferred seat assembly of the invention in a raised condition; Figure 2 is a similar view of the same seat assembly in a lowered condition; Figure 3 is a somewhat enlarged scale partial rear view sketch of the assembly shown in figures 1 and 2 which is taken roughly along the line A-A indicated in figure 2.

Figure 4 is a plan view of the seat assembly shown in Figure 1 with the seat removed.

As illustrated a preferred embodiment of a seat assembly according to the invention comprises a seat (10) mounted upon an upper support frame (12), and, below these, an intermediate support frame (14) and a lower support frame (16). The upper frame (12) comprises a pair of spaced apart right angled beams (22), which extend longitudinally below each side of the seat (10) and are connected by at least one cross piece (24). The beams (22) provide guide tracks for respective slides (26) which are secured to the underside of the seat, whereby the seat (10) is able to slide longitudinally in its own front to rear direction.The intermediate frame (14) comprises a pair of spaced apart box section members (28) connected by box section cross pieces (30), while the lower frame (16) comprises a pair of spaced apart box section members (32) connected by a box section cross piece (34) at the rear and by a right angled beam (36) at the front.

The upper frame (12) carries a pivot tube (38) which fits over and rotates upon a pivot pin (40) provided upon the intermediate frame (14). In this respect, the vertical pivot axis provided by the interconnection of the pin (40) at the tube (38) lies below a rear quadrant of the seat (10), thereby allowing the seat (10) to rotate relative to the sub-assembly comprising the intermediate and lower frames (14), (16) and their linkages (41) - (44), without being impeded by any part of the vehicle, e.g console, in which the assembly may be installed and also in such a way as to bring the front edge of the seat to a position extending beyond the sill of the adjacent vehicle door.

The intermediate frame (14) is connected to the lower frame (16) by means of four substantially parallel, obliquely extending linkage arms (41) - (44). There are two such arms at each side and these are pivotally connected to the respective frames (14), (16) by transversely extending pivot shafts (45) - (48). In use, the illustrated assembly would, of course, be installed in a vehicle with the lower support frame (16) mounted on or adjacent the vehicle floor. The linkage arms (41) - (45) are disposed to extend obliquely upwards in a direction from the vehicle floor towards the front of the vehicle. It is clear by reference to figures 1 and 2 that as the linkage formed by the arms (41) (44) is raised the seat (10) is moved towards the rear of the vehicle as well as being raised.

Raising and lowering of the arms (41) - (44), and hence of the seat (10) is accomplished by an actuator (50) which is secured to the lower frame (16). The actuator (50) has a ram (52) which is pivotally connected to the free end of a lever arm (54) which is attached to a transverse member (56) connecting the two front linkage arms (41, 42) and projects substantially at right angles to the front linkage arms (41, 42). The actuator (50) is preferably electrically operated, but it may alternatively be operated pneumatically or hydraulically or manually.

In the raised condition of the assembly the height X of the subassembly comprising the frames (14), (16) and the linkages (41) (44), as shown in figure 1, is over 2.5 times the height Y of the subassembly in the collapsed condition, as shown in figure 2.

More specifically, the collapsed height Y may be in the region of 64mm, while the raised height X may be in the region of 200mm.

As shown, the length of the linkage arms (41) - (44) and their precise disposition have been chosen so that in the collapsed condition shown in figure 2 the lever arm (54) projects to the rear of the pivot shaft (46) of the intermediate frame (14).

When the illustrated assembly is installed in a standard lowsilled motor car the normal condition will be the lowered condition, as shown in figure 2. For access, the seat will be raised, rotated and slid forwards, outwardly of the adjacent door. The seat need not be raised to its full extent; it can be raised selectively to whatever height is most appropriate to the car and the user. Similarly it can be slid forward only to the extent necessary. Rotation and sliding of the seat can take place at any vertical height and simultaneous with vertical motion of the seat.

When the illustrated assembly is installed in a high-silled, high seated vehicle, such as a four wheel drive motor car, the normal condition will be the raised condition, as shown in figure 1. For access, the seat will be rotated, lowered (which moves it forward too) and slid forwards, outwardly of the adjacent door. Again, the extent of lowering and of seat sliding can be selected by the user, and rotation, sliding and vertical adjustment of the seat can all take place simultaneously.

The invention is not limited to details of the illustrated version, and numerous modifications and variations are possible.

In particular, as mentioned earlier in the text the linkage arms may be disposed to extend obliquely sideways i.e transversely of the longitudinal axis of the seat (when in its unrotated portion) and of the vehicle in some circumstances. Also, the lower frame may be omitted, with the linkage arms mounted either directly to the vehicle body or via equivalent intermediate mounting means.

Claims

1. An adjustable seat assembly for a vehicle comprising upper support means having a seat mounted thereon, intermediate support means and lower support means, the upper support means being pivotally mounted upon the intermediate support means for movement about a substantially vertical axis and the intermediate support means being connected to the lower support means by way of at least two linkage arms which are pivotally connected at or near their respective ends to the intermediate and lower support means, respectively, and an actuator pivotally connected to the linkage arms or to the intermediate support means so as to raise and lower the seat relative to the lower support means by swinging the linkage arms into a raised condition and into a collapsed condition, respectively.

2. A seat assembly as claimed in claim 1 wherein the actuator is in the form of a power-driven ram.

3. A seat assembly as claimed in claim 1 or 2 wherein the actuator is connected to a lever arm which is connected to a transverse member extending between two linkage arms, in which respect the lever arm projects laterally relative to the longitudinal axis of the linkage arms.

4. A seat assembly as claimed in claim 1 or 2 or 3 wherein the actuator is connected directly to the intermediate support means.

5. A seat assembly as claimed in any preceding claim wherein the linkage arms are four in number, two at each side of the seat.

6. A seat assembly as claimed in any preceding claim wherein the linkage arms extend substantially parallel to each other.

7. A seat assembly as claimed in any preceding claim wherein the linkage arms extend obliquely in the lowered (collapsed) condition of the assembly.

8. A seat assembly as claimed in any preceding claim wherein the linkage arms extend obliquely in the same direction in both the raised and lowered (collapsed) conditions of the assembly.

9. A seat assembly as claimed in any of claims 1 to 7 wherein the linkage arms extend substantially vertically in the raised position of the assembly.

10. A seat assembly as claimed in any preceding claim wherein the pivotal connection of the upper support means to the intermediate support means takes place about an eccentric vertical axis, which is located below the rear outer quadrant of the seat.

11. A seat assembly as claimed in any preceding claim wherein the seat is slidable relative to the upper support means in a front to rear direction.

12. A seat assembly as claimed in any preceding claim wherein the lower support means is slidable relative to the vehicle body, in a longitudinal direction thereof.

13. A seat assembly as claimed in any preceding claim wherein the length of the linkage arms and their disposition relative to the intermediate support means and to the lower support means is such that the height of a sub-assembly comprising the intermediate and lower support means and the linkage arms in the raised condition of the assembly is at least 2.5 times the height of that sub-assembly in the collapsed condition of the assembly.

14. A vehicle having an adjustable seat assembly comprising a first support frame pivotally mounted above a second support frame for movement about a substantially vertical axis, the second support frame being connected to the vehicle body by way of at least two linkage arms which are pivotally connected at or near their respective ends to the second support frame and to the vehicle body, or to elements mounted in or on said body, and an actuator pivotally connected to the linkage arms or to the second support frame so as to raise and lower the seat relative to the vehicle body by swinging the linkage arms into a raised and into a collapsed condition respectively.

15. A vehicle as claimed in claim 14 wherein the actuator is in the form of a power-driven ram.

16. A vehicle as claimed in claim 14 or 15 wherein the actuator is connected to a lever arm which is connected to a transverse member extending between two linkage arms, in which respect the lever arm projects laterally relative to the longitudinal axis of the linkage arms.

17. A vehicle as claimed in claim 14 or 15 wherein the actuator is connected directly to the second support frame.

18. A vehicle as claimed in any of claims 14 to 17 wherein the linkage arms are four in number, two at each side of the seat.

19. A vehicle as claimed in any of claims 14 to 18 wherein the linkage arms extend substantially parallel to each other.

20. A vehicle as claimed in any of claims 14 to 19 wherein the linkage arms extend obliquely in the lowered (collapsed) condition of the seat assembly.

21. A vehicle as claimed in any of claims 14 to 20 wherein the linkage arms extend obliquely in the same direction in both the raised and lowered (collapsed) conditions of the assembly.

22. A vehicle as claimed in any of claims 14 to 20 wherein the linkage arms extend substantially vertically in the raised position of the seat assembly.

23. A vehicle as claimed in any of claims 14 to 22 wherein the linkage arms, in the lowered condition of the seat assembly, extend obliquely upwards from the vehicle floor in a direction towards the front of the vehicle so that upon the arms (and hence the seat) being raised the seat inevitably also moves towards the rear of the vehicle.

24. A vehicle as claimed in any of claims 14 to 22 wherein the linkage arms, in the lowered condition of the assembly, extend obliquely upwards from the vehicle floor in a direction away from the longitudinal central axis of the vehicle so that upon the linkage arms and the seat being lowered the seat inevitably moves outwardly of the vehicle.

25. A vehicle as claimed in any of claims 14 to 24 wherein the pivotal connection of the first support frame to the second support frame takes place about an eccentric vertical axis, which is located below the rear outer quadrant of the seat.

26. A vehicle as claimed in any of claims 14 to 25 wherein the seat is slidable relative to the first support frame in a front to rear direction.

27. A vehicle as claimed in any of claims 14 to 26 wherein the distance between the location of mounting of the linkage arms to the vehicle body and the top of the second support frame in the raised condition of the seat assembly is at least three times said distance in the collapsed condition of the seat assembly.

28. An adjustable seat assembly for a vehicle substantially as hereinbefore described with reference to and as illustrated by the accompany drawings.

29. A vehicle having, installed therein, an adjustable seat assembly substantially as hereinbefore described with reference to the accompanying drawings.