Proportioning control valve
US4725101A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 4, 1987 |
| Grant date | Feb 16, 1988 |
| Priority date | — |
| Expiry date | May 4, 2007 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60T8/263
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A proportioning control valve for a fluid pressure braking system for a tractor-trailer combination vehicle permits unproportioned communication of control pressure when the tractor is pulling a trailer but proportions communication of control pressure when the tractor is operated without a trailer to establish a proportonally lower pressure level at the outlet of the valve. The control valve, when operating in the proportioning mode, is also responsive to pressure in the brake reservoir. When pressure in the reservoir drops below a predetermined level, the control valve proportions at a rate which increases the pressure level at the outlet at a rate greater than the rate of increase of control pressure until the unproportioned pressure level is attained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.