Pilot valve
US4789131A · kind A · utility
7Cited by
11References
2Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Sep 9, 1987 |
| Grant date | Dec 6, 1988 |
| Priority date | — |
| Expiry date | Sep 9, 2007 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF01L25/063
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A pilot valve assembly is provided which substantially eliminates stalling in air motors. The pilot valve assembly is located on one end over an air piston such that when the air piston hits the trip rod, the trip rod compresses a trip spring which is in turn compressed until the load of the force stored in this spring is sufficient to overcome the inlet air pressurizing the opposite side of the pilot valve and the main spring which also pre-loads the pilot valve. At this point, air is allowed to pass through the open pilot valve, allowing a spool valve to switch over and reverse the direction of the motor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.