Mechanical Thigh Support

The field of the present invention is that of a vehicle seat. More particularly, the field of the present invention is that of vehicle seats with adjustable thigh supports.

To increase the comfort of a vehicle seat occupant and to lessen fatigue, it is desirable to provide a thigh support whose inclination with respect to the remainder of the seat may be adjusted. An example of such an adjustable thigh support (sometimes referred to as a leg support) is shown and described in commonly assigned U.S. Pat. No. 4,693,513 to Heath.

The present invention provides a manually adjustable thigh support which is an alternative to that shown in Heath which also provides linear as well as radial adjustment.

FIG. 1 is a side elevational view of a preferred embodiment vehicle seat having an adjustable thigh support according to the present invention.

FIG. 2 is an operational view showing the adjustment of the vehicle seat shown in FIG. 1.

FIG. 3 is a top plane view of the vehicle seat shown in FIG. 1 with portions cut away and sectioned.

Referring to FIGS. 1, 2 and 3, the vehicle seat 7 of the present invention has a seat frame 2 which is directly or adjustably connected, via a conventional adjustment device, with the floor of a vehicle (not shown). The seat frame 2 has a rearward portion 4 which provides a seating support surface 6. The seat frame 2 also has a mound 8 for positioning two transversely spaced slotted housings 10 (only one shown). A rearward end 58 of the mound 8 aids in the prevention of submarining of a vehicle occupant in a collision. The slotted housings 10 have an oblong slot 12 and are typically fabricated from a polymeric material and can be attached to the seat frame by a fastener 14. The seat frame also has a forward section or end 50.

Pivotally mounted in a translational and angularly adjustable or radially adjustable manner with respect to the seat frame 2 is a thigh support pan 16. The thigh support pan 16 at its rearward end has two extending pins 18 which fit into the elongated slots 12 of the two spaced-apart slotted housings 10. The thigh support pan 16 has a support surface 52 on its top end for supporting a portion of a seat occupant's leg along a forward end of the seat frame.

Joined by welding or other suitable means to the thigh support pan 16 on a side opposite its support surface 52 is a main gear track 20. The main gear track 20 projects generally downwardly from the thigh support pan. The main gear track 20 has along its forward end a tooth surface 22 and along its rearward end a smooth surface 24. The main gear track 20 will have a curvilinear shape configured in a predetermined manner for purposes to be described later.

Affixed to the forward end 50 of the seat frame is a gear housing 56. The gear housing 56 has rotatably connected thereto a gear 28 and an alignment pin roller 26. The alignment pin roller 26 is spaced from the gear 28 and captures between itself and the main gear 28 the main gear track 20.

Pivotally mounted to the thigh support pan 16 either directly or via the main gear 20 is a receiving gear track 30. The receiving gear track is pivotally mounted by a pin 32 and has a tooth section 34 for selective engagement with the gear 28. To torsionally bias the receiving gear track 30 to engage with the gear 28, there is provided a coil spring 36 connected with a mounting pin 38 of the main gear track and a mounting pin 40 of the receiving gear track. To impart pivotal movement to the receiving gear track 30, there is a stud 42 connected with a handle

It will be apparent to those skilled in the art that in operation, the rear portion 6 of the seat frame 2 and the thigh support pan 16 will be appropriately covered with padding and a seat cover which are only shown in phantom to provide for clarity of illustration. In the position shown in FIG. 1, the thigh support pan 16 is locked from rotation or movement by virtue of the engagement of the gear 28 with the tooth sections 22 and 34 of the main gear track and the receiving gear track 30. To adjust the thigh support pan 16, the vehicle seat occupant pulls upward on handle 44 (FIG. 2), causing the receiving gear track 30 to remove itself from engagement with the gear 28 against the biasing of the spring 36. The configuration of the curvilinear shape of the main gear track 20 is of such a nature that a projection 54 of portion 46 of the thigh support pan front end will be linear during its adjustment, causing the thigh support pan front portion 46 to extend upward approximately 40 millimeters while going forward approximately 10 millimeters. To accommodate the linear movement of the front end 46 of the thigh support pan 16, the pin 18 will move forwardly within the slot 12 during the adjustment to the uppermost position. In an alternative not shown, the main gear track 20 may be configured in such a manner that only radial adjustment is provided. When engaged with the gear 28, the tooth section 34 of the receiving gear track (in contact with gear 28) will be parallel with the tooth section 22 of the main gear track.

While this invention has been described in terms of a preferred embodiment thereof, it will be appreciated that other forms could readily be adapted by one skilled in the art. Accordingly, the scope of this invention is to be considered limited only by the following claims.