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. 31, 1984
Filed:
Dec. 30, 1981
Ronald W McGeehee, Redwood Valley, CA (US);
All American University, Incorporated, Upland, CA (US);
Abstract
An emergency shutdown system for an air-balanced pumping unit which includes a pump motor, a walking beam driven by the pump motor, a rod string reciprocated by the beam, and an air-balance cylinder and an air receiver which together define an air spring for storing energy from the beam is disclosed. A lever arm is pivotally mounted on the walking beam and attached at one end to the rod string so that a rotational moment is exerted in proportion to the weight of the rod string. Such rotational moment is opposed by an air bag, the output force of the air bag being adjustable within the expected range of the rotational moment. Thus, by properly adjusting the air bag, loss of load on the rod string results in movement of the lever arm. A shutdown valve is operatively connected to the lever arm and bleeds air from the air cylinder upon loss of load.