The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 30, 1999
Filed:
Jan. 28, 1997
James A Wood, Spartanburg, SC (US);
Richard J Mazur, Greer, SC (US);
Westinghouse Air Brake Company, Wilmerding, PA (US);
Abstract
A control unit includes several magnet and air piloted valves, a transducer, a transmitter, a pressure switch and a pipe network. Controlled by a central controller, the apply and release valves allow a first trainline to charge the pipe network or vent to atmosphere whereas the emergency release valve can vent a second trainline to atmosphere. The transfer valve connects the first trainline to a command port of the control unit unless its pilot port receives an emergency braking request in which case it connects the pipe network to the command port. The transducer converts pressure in the first trainline to an electrical signal. The transmitter conveys this signal to a control bus. The pressure switch closes if the second trainline charges to a preset pressure. Upon closure of the pressure switch and a command from the controller, the charging valve allows the pipe network to charge the second trainline to a threshold level. The maintaining valve permits the pipe network to charge the second trainline unless pressure at its pilot port falls below the threshold. The regulating valve regulates air from a primary port of the control unit for use in the pipe network. The pipe network allows the apply valve, the first trainline and the regulating valve to supply air to the transfer valve, charging valve, maintaining valve and a master port of the control unit. When pressure in the second trainline drops faster than a predetermined rate, the vent valve vents the second trainline to atmosphere.