Powered six-way seat adjustor and mechanisms therefor

Claim 1

A powered seat adjuster, the adjuster comprising a top, bottom, front, rear and two sides, the adjuster having disposed upon the bottom thereof anchor means for anchoring the seat adjuster to the floor of a vehicle; the anchor means having secured thereto a fixed rail of a seat track, the fixed rail being of generally U-shaped cross-section having two legs extending upwardly away from the anchor means, the upwardly extending legs each having a radially extending flange disposed at the end thereof of predetermined radius of curvature, the fixed rail having inserted therein a moveable rail, slideable within the fixed rail, the moveable rail being of a double "J" cross-section having upwardly extending flanges abutting the flanges of the fixed rail upon bearing surfaces disposed between the flanges of the fixed rail and flanges of the moveable rail; the seat adjuster having disposed at each side thereof a moveable and a fixed rail, the moveable and fixed rails being interconnected to form a seat track assembly within the adjuster, the seat tracks being joined together in part by tubular shafts enclosed and extending through tubular collars joined to the moveable rail at beaded joints for affixing the tubular shafts to corresponding openings within the moveable rail, such fastening being accomplished forwardly and rearwardly within the seat adjuster, the tubular shaft extending through a bell crank, at least one each disposed proximate the front and rear of the seat adjuster for vertically displacing the seat; the bell crank being fastened to a nut having an opening at the end remote the bell crank, the opening being threaded for the insertion of a compatible lead screw, the lead screw being driven by a first drive motor affixed to the seat adjuster for driving the bell crank pivotally and thereby effecting the vertical displacing of the seat, the seat adjuster having a second drive motor for driving at least two lead screws disposed in a substantially horizontal direction from front to rear of the seat adjuster at the sides thereof proximate the seat track, the at least two lead screws being in communication with the second drive motors through gear reduction means which allow the at least two lead screw to rotate at a predetermined speed, horizontally disposed each lead screw having disposed thereon a nut assembly, the assembly having an opening therethrough, the opening being threaded compatibly with the lead screw, the nut assembly having connected thereto a bracket having two ends, the bracket being affixed at one end to the nut assembly and at the other end thereof to the moveable rail of the seat track, thus movement of the nut assembly upon the horizontally disposed lead screws will cause the moveable track to slide within the fixed track, each of the at least two lead screws having disposed at the end thereof mounting means and at least one of the at least two lead screws having disposed at the end of the mounting means anchor means to sustain the rotation of the lead screw and movement of the nut assembly upon the lead screw, each drive motor having two ends and having disposed at one end thereof an integrally mounted gear reduction means from which a lead screw extends and having extending from the other end of the drive motor a shaft of predetermined length extending away from the drive motor towards the lead screw disposed on the other side of the seat adjuster, the shaft thereat connected to a slave gear reduction means for communication with a lead screw disposed thereat for movement at substantially the same rate as the lead screw disposed proximate the drive motor, the nut assembly comprising a first nut of predetermined load bearing capacity, the first nut being affixed to the bracket affixed to the seat track, a second nut affixed to the first nut, the second nut having disposed thereupon a collet, the collet being further affixed to the bracket affixed to the seat track, the second nut being of a predetermined load bearing ability much greater than that of the first nut, whereby when the first nut is subjected to a load which is less than or equal to load bearing capacity of the first nut, the first nut will travel along the extension of the lead screw and thus moving the bracket to which it is interconnected, the bracket being interconnected with the moveable track as well thus effecting the movement of the seat track in the horizontal direction; the second nut and the collet being interconnected with the nut assembly and thus moving along with the nut assembly but not interfering with the nut assembly; however, when the first nut is subjected to a load which is greater than the load bearing capacity of the first nut resulting in the failure of the first nut, such load will be transferred from the seat track to the bracket affixed to the collet, from the collet to the second nut, from the second nut to the lead screw, from the lead screw to the anchor means, from the anchor means to the mounting means, from the mounting means to the structure of the vehicle thereby resolving any loads disposed upon the seat track in a substantially horizontal direction by the nut assembly and the lead screw acting in communication.