Patent ID: 6325468
Filing Date: 2001-12-04
Classification: B60T,G05D,Y10T

Abstract:
A modulator comprising:a housing having a first port adapted for connection with a source of supply pressure, a second port adapted for connection with a brake chamber, and a third port adapted for connection with ambient;a hollow spool valve received in the housing and movable relative thereto for selectively connecting the first port to the second port and an internal passage through the spool valve for selectively connecting the second port to the third port, the internal passage being the only exaust path between the second and third ports;a biasing member interposed between the housing and spool valve for urging the spool valve to a first position that prevents communication between the first and second ports;an actuator operatively associated with the spool valve for urging it to a second position that establishes communication between the first and second ports; anda valve member defined on the actuator for selectively engaging the spool valve, thereby closing communication between the second and third ports and establishing communication between the first and second ports.