Seat positioning device

Claim 1

A SEAT ADJUSTOR OF THE TYPE DESCRIBED COMPRISING IN COMBINATION: A FIRST FRAME MEMBER AND A SECOND FRAME MEMBER INTERCONNECTED BY LINKAGE AT OPPOSITE ENDS THEREOF FOR INDEPENDENT RELATIVE VERTICAL MOVEMENT, A THIRD FRAME MEMBER ADAPTED TO BE SECURED TO THE FLOOR OF AN AUTOMOBILE AND PROVIDED WITH A SUBSTANTIALLY HORIZONTAL TRACK FOR OPERATIVELY RECEIVING A TRACK OF THE FIRST MEMBER FOR RELATIVE LINEAR MOVEMENT THEREBETWEEN, A FIRST HELICALLY THREADED SCREW OF STEEP PITCH NONROTATABLY CARRIED BY THE FIRST FRAME MEMBER, FIRST AND SECOND NUT MEANS MOUNTED ON THE FIRST SCREW AT SPACED-APART LOCATIONS FOR LINEAR MOVEMENT THEREALONG INDEPENDENTLY OF EACH OTHER AND EACH CONNECTED TO THE OPPOSITELY DISPOSED LINKAGE RESPECTIVELY, SAID NUT MEANS OPERATIVELY ENGAGING THE RELATIVELY STEEP HELICAL THREADS OF THE SCREW MEMBER, A SECOND HELICALLY THREADED SCREW HAVING A STEEP PITCH NONROTATABLY SUPPORTED BY THE FIRST FRAME MEMBER AND RECEIVED BY A THIRD NUT MEANS FIXED ON THE THIRD FRAME MEMBER WHEREBY THE SECOND SCREW IS ADAPTED TO RECIPROCATE RELATIVE TO THE THIRD NUT MEANS UPON RELATIVE LINEAR MOVEMENT OF THE FIRST AND THIRD FRAME MEMBERS ALONG THE TRACK MEANS, BIASED LOCKING MEANS CARRIED BY EACH NUT MEANS NORMALLY RESTRAINING RELATIVE AXIAL MOVEMENT BETWEEN THE NUT MEANS AND SCREW WHEREBY THE FIRST, SECOND AND THIRD FRAME MEMBERS ARE FIXEDLY HELD IN A RELATIVE POSITION, AND RELEASE MEANS PERMITTING MANUAL OVERRIDE OF THE NORMALLY BIASED LOCKING MEANS WHEREBY THE NUT MEANS MAY BE MOVED AXIALLY ALONG THE SCREW WHEREBY THE FRAME MEMBERS MAY BE MANUALLY REPOSITIONED AND THERE LOCKED IN ANOTHER RELATIVE POSITION.