Control apparatus for hydraulic lock

In combination, a hydraulic lock having a piston rod extending outwardly from one end thereof and an operating pin slidably contained within the piston rod that protrudes from the terminal end of said piston rod, and a control apparatus for depressing said pin that includes:

• a push button unit connected to a lever arm assembly by a flexible conduit having a cable slidably contained within the conduit;
• said lever arm assembly having platform containing an opening for receiving therein the terminal end of said piston rod so that said terminal end of the piston rod and said pin extend above a top surface of said platform and a lever arm pivotally mounted over said pin so that said lever arm can move into depressing contact with said pin;
• said cable having a proximal end connected to a push button mounted in said push button unit and a distal end connected to said lever arm so that depressing the push button causes the pin to be depressed from an inoperative position to an operative position whereby the hydraulic lock is unlocked;
• said conduit having a distal end that includes a cylindrical rotor that passes upwardly through said platform, said rotor being spaced apart from said piston rod;
• a flat plate rotatably mounted upon the rotor above the top surface of said platform so that the plate rotates about said rotor between a locked and an unlocked position;
• said plate having one side edge that contains an arcuate shaped cutout therein that is arranged to engage a circumferential groove in the terminal end of said piston rod when the plate is in the locked position whereby the piston rod is secured to the platform;
• and
• a detent means acting between the platform and the plate for securing the plate in the locked position.