Vertically reciprocating constant power drive unit for raising a load step by step
US5196770A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 10, 1991 |
| Grant date | Mar 23, 1993 |
| Priority date | — |
| Expiry date | Jun 10, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K41/025
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A vertically reciprocating and substantially constant power drive unit, including pumping equipment situated at the bottom of a string of drive rods is provided. The drive unit comprises a linear electric motor whose field inductor and whose armature are constituted by two coaxial cylindrical parts, one of which is coupled to the top end of the drive rods and is movable relative to a stationary structure. A balancing device exerts a force on the moving equipment constituted by the pumping equipment, the rods, and the motor coupled thereto, which force is equal and opposite to the sum of the weight of the moving equipment plus one-half the weight (H/2) of the load.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.