Abstract: An auxiliary mechanical position locking device is coupled to the hydraulic system that motivates a double acting piston for positional control of surgical tables. The combination of hydraulic coupling and mechanical locking maintains positional stability of the surgical table and insures against sudden or precipitous movements.

Abstract: A linear drive is disclosed comprising a single-acting pneumatic piston cylinder unit, at least one spring which acts against the pneumatic force and loads the piston rod in the direction of one end position, and one form-locking pneumatic locking mechanism respectively for each of the two end positions of the piston rod.

Abstract: A device for operation of a sliding door member, the device being movable between an open position in which the door member is open and a closed position in which the door member is closed. The device includes a pneumatic cylinder having an actuating piston and a rod assembly. A slidable cage sealingly sleeved between the cylinder and the piston reduces the force applied to the piston rod when approaching the open position. When moving towards the first position force is provided initially by conjoined movement of the piston and said cage, and finally by the piston only. A latch for locking the device in the closed position is provided by a spear secured to the piston and rod assembly and a pin to lock the spear disposed in the cylinder. A manual delatching can be achieved by a cable operated spool which moves the pin to unlock the spear.

Abstract: A fluid cylinder assembly comprising a fluid cylinder having ports disposed at opposite ends thereof communicable with a source of fluid under pressure, a piston disposed in said cylinder having a first rod section extending through an end of said cylinder, extendable and retractable relative to said cylinder, the first piston rod section having an axial bore, a second piston rod section having a guide portion disposed in the axial bore of the first piston rod section and axially displaceable relative the first piston rod section, and means for detachably locking the first piston rod section to the second piston rod section.