Spring brake modulating relay valve
US6769744B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 25, 2000 |
| Grant date | Aug 3, 2004 |
| Priority date | — |
| Expiry date | Jul 13, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/86919
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A combined spring brake modulating relay valve integrates the functions of a relay valve and a modulating valve. The housing includes a valve assembly movable in response to air pressure provided to selected ports in the housing. A relay piston selectively communicates with a control port and a primary brake circuit port. A modulating piston includes surfaces selectively pressurized by the primary brake circuit port and a secondary brake circuit port. This modulates the pressure from the delivery port to thereby selectively apply the associated spring brakes if a failure is detected at the primary brake circuit port. The exhaust member selectively controls communication between the supply and delivery ports as necessary.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.