Pneumatic empty/load proportioning for electro-pneumatic brake
AssigneeWestinghouse Air Brake Company
InventorAlbert A. McKay
Life of this patent
Estimating the term…
Abstract
A microprocessor based electro-pneumatic brake system for a railroad car including an emergency backup having load control apparatus under control of the microprocessor and arranged to maintain a load setting consistent with the microprocessor control in the event a power failure or malfunction renders the microprocessor inoperable.
Claims6
A railroad car brake system including a primary brake portion having a microprocessor controller, a backup brake portion having an emergency valve controller, fluid pressure operated brake means, and a double check valve device via which one of said microprocessor controller and said emergency valve controller is effective to operate said brake means, wherein the improvement comprises:
- a) valve means having an activated condition for limiting the fluid pressure effective at said double check valve device when said emergency valve controller is operated;
- b) said microprocessor controller outputting a first control signal in accordance with an empty condition of said railroad car;
- and
- c) empty/load selector valve means operable to a first position in response to said first control signal for establishing said activated condition of said valve means, said empty/load selector valve means being stable in said first position in the absence of said first control signal.
Dependencies are inferred from the claim text.