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:
Apr. 09, 1985
Filed:
Feb. 07, 1983
Jerry L Reeves, Dallas, OR (US);
Towmotor Corporation, Mentor, OH (US);
Abstract
This invention relates to a pump arrangement (54) for use in a linear fluid operated device having a reciprocating piston (14) separating a first active fluid chamber (30) and a second chamber (32) which eliminates the problem associated with fluid leakage buildup developing in the second chamber. The pump arrangement (54) is connected to the reciprocating piston (14) and pumps leakage fluid present in the second chamber (32) from the second chamber (32) and into the first chamber (30) in response to a force of a preselected minimum magnitude being applied to the pump arrangement (54). Thus, the problems of inefficient linear fluid operated device operation, reduced piston stroke length, external fluid leakage, and erratic piston travel speed are eliminated. The pump arrangement (54) is particularly suited for use in a single acting linear hydraulic jack (12) such as used on a material handling vehicle.