Pumping jack
US4191016A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 7, 1978 |
| Grant date | Mar 4, 1980 |
| Priority date | — |
| Expiry date | Jul 7, 1998 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S417/904
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A pumping jack for use with a well having a vertically reciprocable polish rod has a base including a horizontally extending table. A hydraulic cylinder is mounted on the base, with the cylinder axis extending parallel to and above the table. A plunger is reciprocable in the cylinder along the axis and carries with it a block including a first sheave around which a first flexible line is reeved. One end of the first line is affixed to the base, and the other end of the first line extends around a well sheave mounted on the base with the well sheave periphery tangent to the polish rod, the line from the well sheave being affixed to the polish rod. The reciprocating parts are balanced at least in part in either of two ways. In one way, there is a pneumatic chamber variable in volume in accordance with the reciprocation of the polymer and provided with air under an elevated pressure sufficient to counterbalance or offset part of the reciprocating load. In the other way, the plunger carries a second sheave around which a second line is reeved, one end of the second line being secured to the base, and the other end of the second line being reeved around a weight sheave mounted on the ba…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.