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. 13, 1977
Filed:
Jun. 23, 1976
Minoru Saruwatari, Calgary, CA;
Canadian Foremost Ltd., Calgary, CA;
Abstract
A jack pump, such as the type capable of use in pumping crude oil from an oil well, the jack pump including a double acting piston and cylinder motor with the piston rod of the motor being adapted to be connected to the polished rod projecting upwardly from a well head. A variable displacement hydraulic pump, which is driven by a motor or engine, is included in a closed hydraulic loop wherein conduits are connected to a pair of output ports of the pump. A pump control means controls the direction and volume of flow in the loop so as to establish a total velocity profile during the complete pumping cycle and to determine the length and position of the stroke of the piston rod.