Abstract: Air operated hydraulic pump apparatus disclosed is particularly adaptable for use with tilting cab control systems. Reciprocation of a pump plunger to pump control liquid from a reservoir is achieved by a spring biased piston slidable within a cylinder bore and alternately moved in opposite directions by the spring bias and compressed air. A valve of the apparatus has a first position where it supplies compressed air to a first chamber of the cylinder bore so as to act against the spring bias and move the piston in one direction. The spring providing the bias is received within a second chamber of the cylinder bore and moves the piston in the opposite direction when the valve is moved to a second position that terminates the supply of compressed air to the first chamber and exhausts the first chamber to the environment.
Abstract: A latch mechanism for a tilting cab vehicle selectively secures a cab thereof to the vehicle frame in a lower use position against movement to an access position. The latch mechanism includes a keeper preferably mounted on the cab and a base preferably mounted on the frame. A keeper opening of the base receives the keeper upon movement of the cab to the use position. The mechanism also includes a bolt mounted on the base for movement between a latching and a nonlatching position so as to selectively engage and disengage the keeper within the keeper opening to maintain the cab in the use position. A hydraulic cylinder mounted on the base defines a cylinder bore and includes a piston slidable within the bore. A first side of the piston includes a connecting rod portion that fixedly mounts the bolt such that sliding of the piston moves the bolt between its two positions.
Abstract: A lock valve for a double acting cylinder including a housing that defines first and second fluid paths for supplying a control fluid to the cylinder to actuate pushing cylinder extension or pulling cylinder retraction and to positively locate the cylinder in any partially extended position. First and second spaced check valves are respectively disposed along the first and second fluid paths to normally prevent reverse fluid flow therealong from the cylinder. Aligned openings of the check valves are closed by spring biased valve elements thereof from the opposite side of each opening as the other check valve. A bore in the housing between the check valves slidably receives a control piston with first and second actuating portions for respectively moving the check valve elements upon piston movement in opposite directions to open the check valves and permit the reverse fluid flow from the cylinder.