Claims
- 1. A truck control unit to perform a brake load weigh function on a truck of a rail vehicle, such rail vehicle including a controller unit for controlling service braking of wheels on such truck, said truck control unit comprising:
a) a source of fluid pressure; b) an air spring pressure means disposed on a truck of a rail vehicle for receiving a plurality of predetermined air spring pressure limits from a predetermined plurality of air springs pressure switches; c) a brake cylinder control means for receiving said plurality of predetermined air spring pressure limits for determining an emergency braking condition exists, and generating a brake limit condition signal; d) a network communication and valve control means for receiving said brake limit condition signal, for communicating a voltage signal to a common leg of said air spring pressure means in response to said brake limit condition signal, and for generating an energization signal; e) an application valve for receiving said energization signal and for communicating a brake control pressure signal when energized; f) a relay valve for receiving said brake control pressure signal, said relay valve having (i) a supply port connected to said source of fluid pressure, (ii) an output port connected to a brake cylinder of a truck, (iii) a control port for communicating said source of fluid pressure, and (iv) an exhaust port from which to vent such brake cylinder, said relay valve provides, in response to said brake control pressure at said control port, a corresponding pressure to such brake cylinder thereby causing an application of such brakes on such truck; g) a release valve for exhausting pressure received from said control port of said relay valve when said release valve is open; h) a brake control means for converting pressure received from a load sensing system to a feedback signal indicative of a load borne by such truck; and i) a means for granting a load compensation means exclusive control over said application and release valves such that (i) said granting means responds to an indication of an emergency by disconnecting such controller unit from said application and release valves thereby giving said load compensation means exclusive control of said application and release valves whereby said load compensation means compensates for such load borne by such truck during emergency braking and (ii) said granting means responds to an indication of a non-emergency by connecting such controller unit to said application and release valves by which such service braking on such truck is normally controlled with said load compensation means still enabled to compensate for such load borne by such truck during such service braking.
- 2. A truck control unit, according to claim 1, wherein said granting means includes a wheel slip release relay that when energized closes a set of normally open contacts and opens a set of normally closed contacts, each of said normally open contacts when closed completes one of a plurality of conductive paths that electrically interconnects such controller unit with said application and release valves, each of said normally closed contacts when failing to close while said wheel slip release relay is de-energized signifies that a corresponding one of said normally open contacts mechanically associated therewith has failed to open.
- 3. A truck control unit, according to claim 1, wherein said source of fluid pressure is at least one of a main reservoir pressure and a brake pipe pressure.
- 4. A truck control unit, according to claim 1, wherein said brake cylinder control means and said brake control means convert a fluid pressure signal to an electronic signal.
- 5. A truck control unit, according to claim 1, wherein said output port of said relay is connected to a brake cutout means for maintenance purposes.
- 6. A truck control unit, according to claim 1, wherein said predetermined plurality of air spring pressure switches is at least two.
- 7. A truck control unit, according to claim 1, wherein said predetermined plurality of air spring pressure switches is three.
- 8. A truck control unit, according to claim 1, wherein said predetermined air spring pressure limits range from about 60 psi to about 90 psi.
- 9. A truck control unit, according to claim 1, wherein said network communication and valve control means is a neuron style communication control processor.
- 10. A truck control unit, according to claim 2, wherein said granting means further includes a wheel slip lap relay for interrupting a connection between said release valve and said wheel slip release relay to energize said wheel slip release relay, such controller unit by energizing said wheel slip release relay during said emergency permits such controller unit to control said application and release valves for at least a purpose of controlling slipping of such wheels on such truck.
- 11. A truck control unit, according to claim 3, wherein said source of fluid pressure includes both said main reservoir pressure and said brake pipe pressure.
- 12. A truck control unit, according to claim 5, wherein said brake cutout means is at least one of a manually operated valve and an electronically operated valve.
- 13. A method for performing a brake load weigh function on a truck of a rail vehicle, said method includes the steps of:
a) reading a network data packet from a sensor input means; b) determining a braking requirement; c) determining if said braking requirement is an emergency brake condition; d) generating at least one of a yes signal and a no signal indicative of said emergency brake condition; e) communicating said no signal to at least one of a service brake and brake release means, and said yes signal to a means to determine an energization pattern; and f) determining an energization pattern from said means to determine energization pattern.
- 14. A method for performing a brake load weigh function on a truck of a rail vehicle, according to claim 13, wherein step (f) includes the steps of:
a) performing a first lookup, and generating at least one of a first yes signal and a first no signal in response to said first lookup function; b) verifying a present state of said predetermined plurality of air spring pressure switches; c) communicating at least one of said first yes signal to a first plurality of brake cylinder control pressure verification means, and said first no signal to a means to determine a pressure switch fault; d) verifying a first plurality of predetermined pressures; and e) energizing an application valve when said predetermined pressure is verified.
- 15. A method for performing a brake load weigh function on a truck of a rail vehicle, according to claim 14, wherein step (c) includes the steps of:
a) performing a second lookup function and generating at least one of a second yes signal and a second no signal in response to said second lookup function; b) verifying said present state of said predetermined plurality of air spring pressure; c) communicating said second yes signal to a second plurality of brake cylinder control pressure verification means, and said no signal to said brake cylinder control means; d) verifying a second plurality of predetermined pressures, and a predetermined fault condition; and e) energizing said application valve when said predetermined fault condition is verified.
- 16. A method for performing a brake load weigh function on a truck of a rail vehicle, according to claim 14, wherein said first plurality of brake cylinder control pressure verification means is at least two.
- 17. A method for performing a brake load weigh function on a truck of a rail vehicle, according to claim 14, wherein said first plurality of predetermined pressures is at least two.
- 18. A method for performing a brake load weigh function on a truck of a rail vehicle, according to claim 15, wherein said second plurality of brake cylinder control pressure verification means is at least two.
- 19. A method for performing a brake load weigh function on a truck of a rail vehicle, according to claim 15, wherein said second plurality of predetermined pressures is at least two.
- 20. A method for performing a brake load weigh function on a truck of a rail vehicle, according to claim 16, wherein said first plurality of brake cylinder control pressure verification means is four.
- 21. A method for performing a brake load weigh function on a truck of a rail vehicle, according to claim 17, wherein said first plurality of predetermined pressures is four.
- 22. A method for performing a brake load weigh function on a truck of a rail vehicle, according to claim 18, wherein said second plurality of brake cylinder control pressure verification means is three.
- 23. A method for performing a brake load weigh function on a truck of a rail vehicle, according to claim 19, wherein said second plurality of predetermined pressures is three.
- 24. A method for performing a brake load weigh function on a truck of a rail vehicle, according to claim 21, wherein a first predetermined pressure of said first plurality of predetermined pressures is about 49 psi, wherein a second predetermined pressures of said first plurality of predetermined pressures about 52.5 psi, wherein a third predetermined pressure of said first plurality of predetermined pressures is about 55.8 psi, and wherein a fourth predetermined pressure of said first plurality of predetermined pressures is about 58.9 psi.
- 25. A method for performing a brake load weigh function on a truck of a rail vehicle, according to claim 23, wherein a first predetermined pressure of said second plurality of predetermined pressures is about 49.0 psi, wherein a second predetermined pressure of said second plurality of predetermined pressures is about 55.8 psi, and wherein a third predetermined pressure of said second plurality of predetermined pressures is about 58.9 psi.
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is related to U.S. Pat. No. 6,120,109 entitled Universal Pneumatic Brake Control Unit, which is assigned to the assignee of the present invention described and its teachings are incorporated herein by reference thereto.