Dual stage pump and filter system with control valve between pump stages
US5762795A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 25, 1996 |
| Grant date | Jun 9, 1998 |
| Priority date | — |
| Expiry date | Jan 25, 2016 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF04B2205/063
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
An improved dual-stage pump system is provided for the accurate pumping and filtering of viscous fluids. Two hydraulically activated pumps are provided in series with a filter and reservoir disposed in-line between the two pumps. The reservoir acts as a source bottle for the second pump and allows the first pump to pump the viscous fluid through the filter at a rate independent of the dispensing rate of the second pump. By operating the first pump at a rate independent of the second pump, back pressure at the filter is avoided. Each hydraulically activated diaphragm pump is equipped with an improved diaphragm that is pre-formed to the geometries of the process fluid cavity thereby eliminating any inaccuracies in the operation of the pumps due to expansion of retraction of the diaphragm during pump operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.