Damping force control type hydraulic shock absorber
US6817454B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 11, 2002 |
| Grant date | Nov 16, 2004 |
| Priority date | — |
| Expiry date | Dec 11, 2022 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60G2500/114
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A piston connected to a piston rod is slidably fitted in a cylinder having a hydraulic fluid sealed therein. First and second poppet valves having different valve opening characteristics are provided in first and second extension main passages, respectively. A pilot control valve is provided in a sub-passage. The control pressure of the pilot control valve is adjusted by a proportional solenoid, thereby controlling damping force. At the same time, the pressure at the upstream side of the pilot control valve is introduced into back-pressure chambers to adjust the valve opening pressures of the first and second poppet valves. Because the first and second poppet valves are sequentially opened or closed, damping force can be controlled stepwisely, and ideal damping force characteristics can be obtained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.