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:
May. 02, 1989
Filed:
Dec. 14, 1987
Vernon A Kiffmeyer, Hennepen City, MN (US);
Commercial Shearing, Inc., Youngstown, OH (US);
Abstract
An impact relief valve and apparatus is disclosed which includes a hydraulic pump connected by two feed lines to a hydraulic cylinder. A first feed line provides fluid below a piston of the cylinder and the second feed line provides fluid above the piston providing a means to cause reciprocal motion of the piston within a cylinder housing. The piston is provided with at least one impact relief valve adapted to be opened upon impact of the piston with the housing at the top of the stroke of the piston whereby when fluid from the first feed line pushes the piston to the top of its stroke, the impact valve or valves are caused to open allowing any additional fluid pressure from the first line to pass through the second feed line to a suction side of the pump thereby reducing power requirements for the pump. An annular ridge on the cylinder head opens the impact relief valves.