ABS modulator solenoid with a pressure balancing piston
US5979503A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 22, 1997 |
| Grant date | Nov 9, 1999 |
| Priority date | — |
| Expiry date | Aug 22, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/87217
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
An ABS modulator solenoid valve (10), having one electric solenoid (12), in which the valve control piston (14) has a passage (16) therethrough for balancing the pneumatic pressure on both ends (34, 36) of the control piston (14). One end (34) of the piston (14) is disposed in a closed piston chamber (32) while the other end (36) is positioned to contact and position a valve spool (40). The passage (16) extends between the ends (34, 36) of the piston (14). Piston (14) is biased by a spring (50) to a position within the piston chamber (32). When the solenoid (12) is de-energized the piston (14) remains in this position and variable air pressure, from an operator controlled brake valve (126), can be supplied through the valve (10) to a brake chamber (128) for operating the vehicle service brakes. During an ABS application the solenoid (12) is energized to overcome the inlet spring (50) bias and the piston (14) moves into engagement with the valve spool (40). The spool (40) is biased by an exhaust spring (52) to a position wherein the exhaust port (24) is isolated from the supply port (20) and the delivery port (22). When the solenoid (12) is fully energized the piston (14) engages th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.