Patent ID: 7413169

Claim:
A safety mechanism for a hydraulic floor jack, the floor jack including a generally rectangular frame having a forward end and a rearward end with the rearward end having a control handle extending therefrom with a control lever thereon, a pair of longitudinal side flanges extending upward from the frame, a pivotal lifting means mounted on the frame including a pair of parallel lift arms having rearward ends interconnected by a lateral push bar and having forward ends that are pivotable upward for lifting a load as the push bar is translated forward within a pair of longitudinal “U” channel tracks facing inward and attached to the inner side flanges within the frame, and a hydraulic cylinder for pushing the lateral push bar forward and for releasing the lateral push bar rearward along the tracks within the frame, the safety mechanism comprising: a toothed rack bar secured on the vertical wall of at least one of the U channel tracks and extending from the rearward ends to the forward ends thereof; the lateral push bar having a bore holes in at least one of the ends thereof; a generally cylindrical dog slidably supported within each of the bore holes of said push bar and having a proximal end thereof, and having a distal end thereof extendable from the end of said push bar for engaging a corresponding tooth of said rack bar; biasing means urging the distal end of each said dog into said rack bar, for mechanically securing the push bar at a desired position in the tracks, whereby the lift arms are retained in the desired position independent of any release of pushing by the hydraulic cylinder, and means for releasing each said dog from said rack bar by actuating the control lever so that the push bar, and thus the rearward ends of the lift arms, can be translated rearward and the forward ends of the lift arms can be lowered.