Hydraulic-pressure control apparatus and operation-characteristic obtaining apparatus
US7481500B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 3, 2006 |
| Grant date | Jan 27, 2009 |
| Priority date | — |
| Expiry date | Aug 18, 2026 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60T8/90
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
An operation-characteristic obtaining apparatus including an operation-characteristic obtaining portion which obtains, as an operation characteristic of an electromagnetic control valve which includes a coil and which is opened and closed according to at least a relationship between (a) an acting force corresponding to a difference of respective pressures of a working liquid on either side of the electromagnetic control valve and (b) an electromagnetic drive force corresponding to an electric current supplied to the coil, a relationship between (c) a valve switching current as an electric current that is supplied to the coil of the electromagnetic control valve at a time when the electromagnetic control valve is switched between a closed state thereof and an opened state thereof and (d) a difference at the time of the respective pressures on either side of the electromagnetic control valve; and a leakage detecting portion which detects, when the operation-characteristic obtaining portion obtains the operation characteristic of the electromagnetic control valve, whether the electromagnetic control valve has a leakage of the working liquid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.