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:
Dec. 06, 1994
Filed:
Jul. 15, 1993
Robert A Mills, Calgary, AB, T2V 3N5, CA;
Other;
Abstract
A drive head for a down hole rotary pump driven from a well head assembly by a drive string that extends through the well to the pump is disclosed. The drive head includes a hollow rotatable drive shaft having an axial passage for accommodating a slip shaft, a housing attachable to the well head assembly, radial bearings centering the drive shaft in the housing and a thrust bearing for supporting the weight of the drive shaft and the drive string suspended therefrom. A pulley is mounted on the shaft for driving the drive shaft. The slip shaft is mounted to the top end of a polished rod which is attached to a top end of the drive string. The slip shaft and the passage in the drive shaft are preferably hexagonal so that drive torque is transmitted to the drive string without slippage of the shaft. The drive string is suspended in the well by a clamp that grips a top end of the slip shaft and rests on a top of the housing. The advantages include the elimination of damage to the polished rod and/or the down hole pump due to polished rod clamp slippage, improved transmission of drive power, and a drive train that cannot be lost down the well when a clamp slips or breaks.