Downhole pump of constant differential hydraulic pressure
US5290159A · kind A · utility
5Cited by
12References
7Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 4, 1993 |
| Grant date | Mar 1, 1994 |
| Priority date | — |
| Expiry date | Mar 4, 2013 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF04B49/121
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A combination low-pressure, high-pressure hydraulic pump which allows a constant differntial pressure is disclosed. This pump features dual concentric pistons, each with its own chamber. The pistons reciprocate together at low pressures; as the system pressure increases, a spring resists the stroke of the low pressure piston, so that ultimately only the smaller, high pressure piston reciprocates.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.