Unloader and check valve
US4470428A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 21, 1982 |
| Grant date | Sep 11, 1984 |
| Priority date | — |
| Expiry date | May 21, 2002 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/7841
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A combined unloading valve and check valve (10) for use with a motor driven air compressor. The unloading valve (16) includes a spool (30) axially movable within a tubular body (12). In the unloading position of the valve, one of two spaced-apart ring seals (32) on the spool is out of engagement with the body to open a flowpath from the inlet of the valve past the spool to exhaust ports (28) formed in the body. When the compressor is operating and the valve is pressurized, both ring seals engage the body to close off the flowpath. The check valve (18) extends beyond the end of the body and includes a poppet valve element (50) which engages a valve seat (52) formed on an end of the spool. When the unloading valve and check valve is installed in a wall (14) of an air tank the check valve extends into the air supply within the tank, thereby helping to cool the internal elements of the valve structure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.