Electropneumatic brake control valve

• US 6,457,782 B1
• Filed: 05/21/1998
• Issued: 10/01/2002
• Est. Priority Date: 09/06/1996
• Status: Expired due to Term

• Current Assignee: New York Air Brake Corporation (Knorr-Bremse GmbH)
• Original Assignee: New York Air Brake Corporation (Knorr-Bremse GmbH)
• Inventors: McLaughlin, Bryan M., Truglio, James R.
• Primary Examiner(s): Schwartz, Christopher P.
• Assistant Examiner(s): TORRES WILLIAMS, MELANIE
• Application Number:
  US09/083,425
• Time in Patent Office: 1,594 Days
• Field of Search: 303/3, 303/15, 303/20, 303/7, 303/36, 303/16, 303/80, 701/92
• US Class Current: 303/7
• CPC Class Codes: B60T 13/665 the systems being specially adapted for transferring two or more command signals, e.g. railway systems B60T13/662 takes precedence

Abstract

An electropneumatic brake control valve unit capable of operating at the interface of the emergency brake portion or the service brake portion of a standard brake control valve as a retrofit unit or operating as a stand alone electropneumatic unit. The unit includes electric valves responsive to electrical signals and sensed brake pipe pressures to operate pneumatic valves to control the brake cylinder. The pneumatic valves are also operable independent of the electric control valves so as to allow braking with the electrical controls off or disabled. The unit can operate in combination with a complete brake control valve or with either or none of its emergency and service portions.

Claims

1. An electropneumatic retrofit unit for a pneumatic brake control valve having a pipe bracket and an emergency brake portion and a service brake portion connected to said pipe bracket at first and second faces, said pipe bracket having passages connecting a brake pipe port, a brake cylinder port and an emergency reservoir port to respective interface brake pipe ports, interface brake cylinder ports and interface emergency reservoir ports on said faces, the retrofit unit comprising:

an EP interface having an EP brake pipe port, an EP brake cylinder port and EP brake signal port; and

an EP emergency reservoir port for mating with said interface brake pipe port, said interface brake cylinder port and said interface emergency reservoir port respectively at either of said faces;

an electrical control valve, connected to said EP emergency reservoir port and having a venting port and an output port, for selectively connecting said output port to said venting port for releasing a brake or to said EP emergency reservoir port for applying said brake; and

pneumatic isolation valve, responsive to pressure in said EP brake pipe passage, for selectively interconnecting said EP brake signal port and EP brake cylinder port when said EP brake pipe port pressure signals a brake application and connecting said output of said electrical control valve to said EP brake cylinder port when said EP brake pipe port pressure signals a brake release.

2. A retrofit unit according to claim 1 wherein said pneumatic isolation valve is connected to said EP emergency reservoir port and is responsive to the differential pressure between said EP brake pipe port and said EP emergency reservoir port.

3. A retrofit unit according to claim 1 wherein said pneumatic isolation valve connects said first brake cylinder passage to the larger pressure of pressure of output of said electrical control valve and of said EP brake signal port.

4. A retrofit unit according to claim 1 wherein said pneumatic isolation valve includes:

a pilot valve, responsive to pressure in said EP brake pipe port, for selectively connecting a pilot valve output to either an exhaust port or said output of said electrical control valve; and

a double check valve selectively connecting said EP brake cylinder port to either said EP brake signal port or said pilot valve output.

5. An electropneumatic retrofit unit for a pneumatic brake control valve having a pipe bracket and an emergency brake portion and a service brake portion connected to said pipe bracket at first and second faces, said pipe bracket having passages connecting a brake pipe port, a brake cylinder port and an emergency reservoir port to respective interface brake pipe ports, interface brake cylinder ports and interface emergency reservoir ports on said faces, the retrofit unit comprising:

an EP interface having an EP brake pipe port, an EP brake cylinder port and EP brake signal port; and

an EP emergency reservoir port for mating with said interface brake pipe port, said interface brake cylinder port and said interface emergency reservoir port respectively at either of said faces;

an electrical control valve, connected to said EP emergency reservoir port and having a venting port and an output port, for selectively connecting said output port to said venting port for releasing a brake or to said EP emergency reservoir port for applying said brake; and

pneumatic valve, responsive to pressure in said EP brake signal port and at said output port of said electrical control valve, for selectively interconnecting said EP brake signal port and said EP brake cylinder port when said EP brake signal port'"'"'s pressure signals a brake application and connecting said EP emergency reservoir port to said EP brake cylinder port when said EP brake signal port'"'"'s pressure signals a brake release and said output port of said electrical control valve signals a brake application.