Electro-proportional pressure control apparatus
US4055197A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 10, 1976 |
| Grant date | Oct 25, 1977 |
| Priority date | — |
| Expiry date | Sep 10, 1996 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/2409
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
The invention contemplates improved hydraulic-pressure control apparatus which will proportionally reflect input-signal changes governing a wide range of output pressures. Use of a separate preamplifier stage, between a signal-pressure stage and a power stage, enables the signal pressure to remain essentially unaffected by load reaction or other transients at the power stage. In the forms described, an input electrical signal determines a step-function program of signal-pressure levels, and the power stage includes a relief valve which so diverts system-line flow to a sump as to assure quick and accurate response of system-line pressure to the instantaneous input electrical-signal level, all without system-pressure overshoot.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.