Bootstrap power steering systems
US5755097A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 21, 1996 |
| Grant date | May 26, 1998 |
| Priority date | — |
| Expiry date | Feb 21, 2016 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB62D5/083
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
Methods and apparatus for improving control of pressurized fluid flow through bootstrap power steering systems are disclosed. In particular, the methods include differentially measuring control pressure across internal flow control orifices as directly as possible. Differential control pressure measurements are made between Kelvin supply, or return, pressure values and a control pressure port of a control valve. In addition, methods and apparatus for improved speed sensitive control of steering assist and/or driver selectable steering effort are also disclosed. One of the methods comprises an extension of the method of differentially measuring control pressure across the internal flow control orifices wherein a range of control pressures are enabled. In addition, a method of improving low speed tactile steering feel wherein an electronically variable orifice is activated in order to provide additional fluid flow thereby increasing "on-center" hydraulic pressure gain is disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.