Drain valve
US4768542A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 4, 1987 |
| Grant date | Sep 6, 1988 |
| Priority date | — |
| Expiry date | Nov 4, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/7782
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A piston (36) divides the valve interior into a main chamber (38) and a sensing chamber (40). A fixed valve seat (26) sealingly engages the piston (36) to close communication between the chambers (38, 40). The seat (26) is carried by an axial stem (20) which extends through an opening (42) in the piston (36). The valve inlet (14) extends through a passageway (22) in the stem (20) into the main chamber (38). An outlet (28) is formed in the main chamber (38). A valve element (62) closes the outlet (28). When pressure is higher in the main chamber (38) than in the sensing chamber (40), the piston moves toward the sensing chamber (40) to open communication between the chambers (38, 40). When there is a pressure drop in the main chamber (38), the piston (36) moves toward the main chamber (38) to open communication between the chambers ( 38, 40) and move the valve element (62) into an open position. A flange (46) caried by the piston (36) engages a flange (80) formed on a hat-shaped retainer (72) to which the valve element (62) is attached. The valve (8) preferably has a manual drain lever (88).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.