Pressure modulating and reducing valve
US4478237A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 11, 1983 |
| Grant date | Oct 23, 1984 |
| Priority date | — |
| Expiry date | Jul 11, 2003 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/2607
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A pressure modulating and reducing valve (10) communicates pressurized hydraulic fluid from a pump (11) to a hydraulically actuated clutch of a transmission at a modulated rate of pressure rise and at a reduced pressure. In order to provide a compact valve, the valve (10) has a pressure reducing valve spool (61) slidably nested within a sleeve member (46) of a load piston to provide a valving action therebetween for controlling fluid flow between an inlet port (24), a load port (26) and a drain port (27) in a body (19). Movement of the sleeve member (46) causes an increase in the pressure at the load port (26) which causes the pressure reducing valve spool (61) to move against a spring (77,78) to establish a pressure in the load port (26) proportional to the travel distance of the sleeve member (46). Movement of the sleeve member (46) is controlled by a solenoid control valve (85) having a spool (86) slidably nested within a projection (54) of an end wall (51) extending into a bore (62) of the pressure reducing valve spool (61).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.