Hydraulic control system
US4381699A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 20, 1980 |
| Grant date | May 3, 1983 |
| Priority date | — |
| Expiry date | Mar 20, 2000 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/86622
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A hydraulic control system for use in machine tools, construction machines, hoists and the like, with a driven unit the hydraulic circuit of which is controlled by one or more electromagnetically positioned slide valves, and with an arrangement for automatically regulating the velocity of the hydraulic drive unit regardless of fluctuations in the pressure of the oil supply and similar disturbances. The regulating arrangement includes a potentiometer mechanically controlled by a flow meter interposed in the hydraulic circuit; and an electric comparator the inputs of which are connected to the potentiometer and to a desired-flow-value selector, respectively, and the output of which controls the valve electromagnet(s). In this manner the difference signal developed by the comparator is used to change the setting of the valve in a correcting sense. Several implementations for this regulating circuit and for the design of the flow meter and the valves are disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.