The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 05, 1978
Filed:
Jun. 13, 1977
Clarence A Sherman, Birmingham, MI (US);
Other;
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. After movement of the piston for a predetermined extent against the bias of the spring, a first actuator moves the valve from the first position thereof to the second position and then allows the spring to act and return the piston. A second actuator on the piston engages the valve upon the return piston movement and moves the valve from the second position back to the first position so that the first chamber is again isolated from the environment and subsequently fed compressed air that begins another cycle. A manual pump is used in addition to the air operated pump and both pumps feed a control valve for directing the flow of pumped liquid from the reservoir.