Actively controlled automotive suspension system with line pressure control under low fluid source pressure
US4865348A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Mar 4, 1988 |
| Grant date | Sep 12, 1989 |
| Priority date | — |
| Expiry date | Mar 4, 2008 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60G2600/72
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
An actively controlled suspension system employs a shut-off valve which is responsive to a source pressure dropping below a predetermined level to shut-off communication between a pressure return line for returning the fluid pressure to the pressure source from a hydraulic cylinder. The shut-off valve is disposed in a drain line connecting a drain port of a spool valve assembly and the pressure source. By the presence of the shut-off valve, substantial pressure difference between the hydraulic cylinder side and pressure source side of the spool valve is not created. Therefore, no leakage through the spool valve occurs and whereby the pressure in the hydraulic cylinder can be maintained even when the source pressure becomes substantially low or zero.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.