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:
Jul. 21, 1998
Filed:
Sep. 20, 1996
Lawrence P Rothering, New Berlin, WI (US);
Applied Power Inc., Butler, WI (US);
Abstract
A hydraulic pump assembly for powering a hydraulic torque wrench is air-powered and has hydro-pneumatic control circuitry which continues operation of an air motor which drives the hydraulic pump for a post-advance period after an advance actuator is deactuated. Operation of the pump is continued for a period sufficient to retract a double-acting torque wrench, to permit subsequent advances of the wrench within the post-advance period without restarting the pump or to permit a single acting wrench to be moved from one fastener to the next within the post-advance period without restarting the pump. Operation of the pump is terminated when the post-advance period expires if the advance actuator is not reactuated, so as to conserve energy and avoid unnecessary heating of the hydraulic fluid.