Patent ID: 8794718
Filing Date: 2014-08-05
Classification: B60T,F16K,Y10T

Abstract:
1. A valve unit for an electro-pneumatic brake control device for controlling a vehicle brake, said valve unit in communication with a control input of an air-flow-boosting valve device for at least one of (i) controlled admission of air into said valve device and (ii) controlled venting of said valve device, said valve unit comprising an orifice, at least one connecting member, and a double-armature solenoid valve having a spring-loaded primary armature and a spring-loaded secondary armature disposed in a common armature-guide arrangement, each of said primary and secondary armatures being actuatable by a common solenoid, said primary armature being configured to operate a vent valve for venting air from said control input of said air-flow-boosting valve device, said vent valve having an outlet disposed adjacent to said orifice and coupled to a first connecting member of said at least one connecting member, said first connecting member being disposed at an end of said valve unit proximate said vent valve, and said secondary armature being configured to operate an air-admission valve for admitting air into said control input, wherein both said primary armature and said secondary armature are positioned in spring-loaded home position when said solenoid is de-energized such that said air-admission valve shuts off admission of air and said vent valve activates venting, wherein in response to injection of a first solenoid current of preselected intensity flowing through said solenoid, (a) said primary armature is positioned in a primary switched position determined by a magnetic force, and (b) said secondary armature is positioned in said spring-loaded home position, such that said air-admission valve shuts off air admission and said vent valve shuts off venting, wherein in response to injection of a second solenoid current of preselected intensity flowing through said solenoid, said second solenoid current being greater than said first solenoid current, (c) said primary armature is positioned in said primary switched position, and (d) said secondary armature is positioned in a secondary switched position determined by said magnetic force, such that said air-admission valve activates air admission and said vent valve shuts off venting, wherein said outlet and said orifice are in separate communication with said first connecting member, and wherein said vent valve is configured to vent air from said control input through said first connecting member via at least one of said orifice and said outlet.