Power-assisted steering system
US5761627A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 12, 1995 |
| Grant date | Jun 2, 1998 |
| Priority date | — |
| Expiry date | Oct 12, 2015 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF04B2203/0208
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A power-assisted steering system for a vehicle comprising a hydraulic motor (1) for providing vehicle steering assistance, an open center servo-valve (6) for supplying the hydraulic motor (1) with hydraulic fluid, a hydraulic pump (7) for supplying hydraulic fluid to the servo-valve (6) and to the hydraulic motor (1), and an electric motor (13) for driving the hydraulic pump (7). The hydraulic pump (7) is controlled by controlling electrical power consumed by the electric motor (13). At least one sensor (15) repetitively monitors at least one operating parameter of the power-assisted steering system. At least one microprocessor (17) repetitively calculates reference values that vary as a function of a monitored level of the at least one operating parameter. Control of the electrical power consumed by the electric motor (13) is based on a comparison of reference values calculated as a function of a first monitored level of the at least one operating parameter with a second subsequent monitored level of the at least one operating parameter. The at least one microprocessor (17) is operable to recalculate the reference values as a function of the second monitored level of the at least …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.