Patent ID: 8668038

Claim:
An actuator for tilting a cab of a vehicle between a driving position and a maintenance position, the actuator comprising: a cylinder housing having an internal cavity, a rod end and a bore end; a piston rod disposed partially within the internal cavity, wherein: the piston rod is configured to move axially in a reciprocating manner relative to the cylinder housing; the piston rod has an exposed portion extending from the rod end of the cylinder housing which varies in length as the piston rod extends or retracts relative to the cylinder housing; and the piston rod has an enclosed portion within the cylinder housing which varies in length as the piston rod extends or retracts relative to the cylinder housing; a pressure cavity formed between an inner surface of the cylinder housing and the piston rod, wherein: the piston rod is forced to extend from the cylinder housing when hydraulic fluid is supplied to the pressure cavity; and the piston rod is allowed to retract under an external force exerted axially on the exposed portion of the piston rod when the hydraulic fluid is allowed to flow from the pressure cavity; a lost motion bore formed in the enclosed portion of the piston rod; a lost motion piston disposed within the lost motion bore, wherein: the lost motion piston divides the lost motion bore into an isolated gas cavity and a fluid cavity; the fluid cavity is in fluid communication with the pressure cavity; and a gas is disposed in the isolated gas cavity; a pressure port disposed on the cylinder housing, wherein: the pressure port is in fluid communication with the pressure cavity; and the pressure port is configured to be connected alternately to a source of hydraulic fluid under a higher pressure or a receptacle of hydraulic fluid under a lower pressure.