Abstract: A locking device for a hydraulic floor jack includes a base member attached to a pair of spaced side plates of such jack. An elongated ratchet member is mounted for linear movement within the base member and is attached to a piston rod of a hydraulic cylinder and to a load lifting linkage. A shaft is pivotally mounted to the base member and a holding pawl is secured to the shaft for rotation therewith. The holding pawl is engageably cooperative with the ratchet member for retaining such load lifting linkage in the elevated position upon termination of a manual actuating effort. A release foot pedal or a release lever is connected to the shaft and manually operable to at least move the holding pawl away from engagement with the ratchet member and enable movement of the load lifting linkage into the lowered position.

Abstract: Disclosed is a self locking hydraulic jack for lifting an automobile provided with an arm lock mechanism and foot pedal so that the lifting arm is prevented from inadvertently falling from mechanical failure or due to loss of hydraulic pressure. The safety to the user of the garage jack is enhanced. Additionally, self locking hydraulic jack is provided with a foot pedal for ease of activation or de-activation.