Steering valve with closed center
US5870941A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 17, 1997 |
| Grant date | Feb 16, 1999 |
| Priority date | — |
| Expiry date | Nov 17, 2017 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB62D5/083
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
The invention concerns a steering valve with a closed center for supplying an actuator with hydraulic pressure, the steering valve comprising an input shaft, and output shaft, a torsionally resilient element which is connected at one end to the input shaft and at the other end to the output shaft, a control pressure switching arrangement and a torque/axial force conversion unit. A spring loaded seat valve is located in a bore of the input shaft, and closes a fluid passage passing through the torsion tube. The torque/axial force convertor opens the seat valve when relative twisting of the input shaft with respect to the valve casing occurs. According to the invention, in order to improve the response dynamics of such a steering valve, the valve comprises at least one axial bore for supplying hydraulic pressure. At one end this bore is closed by a valve which is loaded by the torque/axial force conversion unit against the hydraulic pressure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.