Method for detecting leaks in a brake pressure line, under braking pressure, of a rail vehicle

Patent metadata

Field	Value
Publication number	US-9669818-B2
Application number	US-201314413018-A
Country	US
Kind code	B2
Filing date	Jul 5, 2013
Priority date	Jul 6, 2012
Publication date	Jun 6, 2017
Grant date	Jun 6, 2017

Abstract

A method for detecting leaks in at least one brake pressure line, under braking pressure, of a compressed air brake device of a rail vehicle having an indirect electro-pneumatic brake, wherein the indirect electro-pneumatic brake has a master air vessel line to hold a master air vessel line pressure, and a compressed air source supplying the master air vessel line with compressed air and is controlled by the master air line pressure in a master air line, wherein the at least one brake pressure line under braking pressure extends between a valve device, which controls the braking pressure in dependence upon the master air line pressure in the master air line, and at least one brake actuator, and where the braking test method is carried out when the rail vehicle is stationary.

First claim

The invention claimed is:

1. A method for detecting leaks in at least one brake pressure line, under braking pressure, of a pneumatic brake device of a rail vehicle that includes an indirect electro-pneumatic brake, which indirect electro-pneumatic brake has a main air reservoir line for carrying a main air reservoir line pressure and a compressed air source supplying the main air reservoir line with compressed air and is controlled by the main air line pressure in a main air line, the at least one brake pressure line which is under the braking pressure extending between a valve device which modulates the braking pressure in dependence on the main air line pressure in the main air line and at least one brake actuator, the method comprising:
checking whether the main air reservoir line pressure exceeds a predefined limit value when the replenishment of compressed air from the compressed air source to the main air reservoir line is cut off and, in response to the main air reservoir line pressure exceeding a predefined limit value, controlling the main air line pressure in the main air line so as to apply the at least one brake actuator;
monitoring the main air reservoir line pressure to determine whether
the value of the main air reservoir line pressure established after the application of the at least one brake actuator deviates by more than a predefined difference from a predefined plausible value for the main air reservoir line pressure, and/or
whether the pressure gradient of the main air reservoir line pressure exceeds a predefined pressure gradient in the interval between the start and the end of the application of the at least one brake actuator; and
generating an error message indicating a leak is present in the at least one brake pressure line in response to the value of the main air reservoir line pressure established after the application of the at least one brake actuator deviating by more than the predefined difference from a predefined plausible value for the main air reservoir line pressure, and/or the pressure gradient of the main air reservoir line pressure exceeds the predefined pressure gradient in the interval between the start and the end of the application of the at least one brake actuator,
wherein the checking and monitoring are performed while the rail vehicle is stationary.

2. The method of claim 1 , wherein the checking and monitoring are carried out manually, in a user-guided manner or automatically, during which the main air line pressure in the main air line is controlled at least periodically so as to apply the at least one brake actuator.

3. The method of claim 1 , wherein during the brake test an electro-pneumatic control of the main air line pressure in the main air line is shut off by a control valve arrangement including a discharge solenoid valve and a brake solenoid valve.

4. The method of claim 1 , wherein the error message is displayed on a display and/or is stored in a diagnostic memory.

5. A pneumatic brake device of a rail vehicle including an indirect electro-pneumatic brake claim 1 for carrying out the method as claimed in claim 1 , the brake device comprising:
at least one device for detecting the main air reservoir line pressure,
an evaluation device which is configured such that it monitors the main air reservoir line pressure to determine whether the value of the main air reservoir line pressure established after the application of the at least one brake actuator deviates by more than a predefined difference from a predefined plausible value for the main air reservoir line pressure, and/or whether the pressure gradient of the main air reservoir line pressure exceeds a predefined pressure gradient in the interval between the start and the end of the application of the at least one brake actuator, and generates an error message indicating a leak is present in the at least one brake pressure line in response to the value of the main air reservoir line pressure established after the application of the at least one brake actuator deviating by more than the predefined difference from a predefined plausible value for the main air reservoir line pressure, and generates an error message indicating a leak is present in the at least one brake pressure line in response to the pressure gradient of the main air reservoir line pressure exceeding the predefined pressure gradient in the interval between the start and the end of the application of the at least one brake actuator, in the course of a brake test carried out with the rail vehicle stationary, and
at least one display for displaying the error message or a diagnostic memory for storing the error message.

6. The pneumatic brake device of claim 5 , wherein the device for detecting the main air reservoir line pressure includes at least one pressure sensor arranged in the main air reservoir line.

7. The pneumatic brake device of claim 5 , wherein the evaluation device is formed by an electronic control unit.

8. The pneumatic brake device of claim 5 , wherein the compressed air source is at least one compressor or a compressed air storage reservoir.

9. The pneumatic brake device of claim 5 , wherein the indirect electro-pneumatic brake further has an electro-pneumatic control of the main air line pressure in the main air line, which control is carried out by a control valve arrangement including a discharge solenoid valve and a brake solenoid valve, a control inlet of a relay valve being controlled by the main air line pressure controlled by the electro-pneumatic control device, which relay valve modulates the braking pressure delivered via the at least one brake pressure line to the at least one brake actuator in dependence on the controlled main air line pressure.

10. The pneumatic brake device of claim 9 , wherein the at least one brake pressure line is formed by a brake pressure hose for supplying the at least one brake actuator of an axle of a bogie having two axles with braking pressure.

11. The pneumatic brake device of claim 9 , wherein at least one anti-slip valve is arranged between the relay valve and the at least one brake actuator.

12. The pneumatic brake device of claim 5 , further comprising a direct electro-pneumatic brake having an electro-pneumatic pressure regulator which, with the aid of a brake solenoid valve and a discharge solenoid valve, generates from the main air reservoir line pressure a pilot control pressure for a further control inlet of the relay valve, which relay valve modulates the braking pressure delivered to the at least one brake actuator in dependence on the pilot control pressure.

13. The pneumatic brake device of claim 12 , wherein the indirect electro-pneumatic brake is provided for rapid braking and the direct electro-pneumatic brake is provided for service braking.

Assignees

• Knorr Bremse Systeme
• Knorr-Bremse Systeme Fur Schienenfahrzeuge Gmbh

Inventors

• Kull Alexander
• Minnecker Bodo
• Feucht Daniel

Classifications

• G01M17/08

  Railway vehicles · CPC title

• G01M3/26

  by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors · CPC title

• G01L5/28

  for testing brakes · CPC title

• B60T17/228 Primary

  for railway vehicles · CPC title

• B60T13/741

  acting on an ultimate actuator · CPC title