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:
Aug. 14, 2018
Filed:
Dec. 31, 2014
Applicant:
Zedi Canada Inc., Edmonton, CA;
Inventor:
Minhao Yin, Calgary, CA;
Assignee:
Zedi Canada Inc., , CA;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F04B 47/14 (2006.01); E21B 43/12 (2006.01);
U.S. Cl.
CPC ...
F04B 47/145 (2013.01); E21B 43/126 (2013.01);
Abstract
A pump jack system for vertically reciprocating a downhole pump in an oil and gas well. The pump jack system includes a cylinder assembly having a drive cylinder and two balance cylinders. A piston in the drive cylinder may be used to provide an upstroke of a sucker rod string of a downhole pump. The pistons in the balance cylinders may be used to provide a downstroke of the sucker rod string. Lower chambers in the balance cylinders counterbalance the lifting and lowering of the piston in the drive cylinder. The pump jack system also includes an accumulator for maintaining a relative constant fluid pressure in the lower chambers of the balance cylinders.