Air brake system monitoring for pre-trip inspection

• US 20050273227A1
• Filed: 06/07/2004
• Published: 12/08/2005
• Est. Priority Date: 06/07/2004
• Status: Active Grant

• Current Assignee: International Truck Intellectual Property Co. LLC (Volkswagen AG)
• Original Assignee: International Truck Intellectual Property Co. LLC (Volkswagen AG)
• Inventors: Fogelstrom, Kenneth A.
• Granted Patent: US 7,363,127 B2
• Time in Patent Office: Days
• US Class Current: 701/29
• CPC Class Codes: B60T 13/26 Compressed-air systems
• CPC Class Codes: B60T 17/02 Arrangements of pumps or compressors, or control devices therefor
• CPC Class Codes: B60T 17/22 Devices for monitoring or checking brake systems; Signal devices

Abstract

Vehicles equipped with air brake systems and compressed air systems for supporting operation of the brakes provide for automated inspection of the air compressor system using an onboard vehicle or engine management computers. During vehicle operation, the system continuously monitors tank leakage, charge time, cut-in and cut-out pressures. Based on the results of this monitoring, the system can indicate whether or not a manual inspection is necessary. If not necessary provides driver with evidence of lack of need.

Claims

1. A motor vehicle comprising:

a compressed air storage tank and air distribution system;

an air compressor coupled to the compressed air storage tank and air distribution system for charging the air storage tank;

a governor responsive to pressure in the compressed air storage tank and air distribution system controlling cut-in and cut-out of the air compressor;

an air pressure sensor located in communication with the compressed air storage tank and air distribution system for sensing air pressure and generating an air pressure signal; and

a vehicle body computer connected to receive the air pressure signal and programmed to respond to values assumed by the air pressure signal for determining leakage rate and charging rate related values for the the compressed air storage tank and air distribution system and for providing warning signals where leakage and changing rate values fail predefined values.

2. The motor vehicle as set forth in claim 1, further comprising:

an air brake system connected to utilize compressed air from the compressed air storage tank and air distribution system;

a brake pedal for actuating the air brake system; and

a brake pedal position sensor connected to the information processor indicating status of the brake pedal.

3. The motor vehicle as set forth in claim 2, further comprising:

the vehicle body computer being further programmed to be responsive to status of the brake pedal for determining leakage in actuated and unactuated states of the air brake system.

4. The motor vehicle as set forth in claim 3, further comprising:

the vehicle body computer being further programmed to determine for leakage rate related values a current leakage rate for the actuated state of the air brake system and a current leakage rate for the unactuated state of the air brake system.

5. The motor vehicle as set forth in claim 4, further comprising:

the vehicle body computer being further programmed to determine for leakage rate related values a plurality of averages of the leakage rates for the actuated and unactuated states of the air brake system over predetermined periods of time.

6. The motor vehicle as set forth in claim 3, further comprising:

the vehicle body computer being further programmed to determine a current charging rate for the charging rate related values.

7. The motor vehicle as set forth in claim 6, further comprising:

the vehicle body computer being further programmed to determine charging rate related values based on averages of engine RPM'"'"'s over predetermined periods of time.

8. The motor vehicle as set forth in claim 5, wherein the motor vehicle is a combination vehicle.

9. The motor vehicle as set forth in claim 7, wherein the motor vehicle is a combination vehicle.

10. An air compression, storage and distribution system comprising:

a governor responsive to changes in air pressure in the air compression, storage and distribution system for pumping air into the system;

a pressure sensor coupled to a point in the air compression, storage and distribution system for generating a signal reporting pressure at that point;

data processing means responsive to the signal reporting pressure for determining rates of charging and leakage of the air compression, storage and distribution system; and

the data processing means providing for comparing the determined rates of charging and leakage against thresholds and generating warnings should either of the rates of charging or of leakage fail the comparisons.

11. An air compression, storage and distribution system as set forth in claim 10, further comprising:

the air compression, storage and distribution system being installed on a motor vehicle and coupled to support operation of an air brake system; and

a brake pedal position sensor connected to apply a brake pedal position signal to the data processing means.

12. An air compression, storage and distribution system as set forth in claim 11, the motor vehicle further comprising a combination vehicle including a truck and a tractor, both of which are equipped with the air brake system.

13. An air compression, storage and distribution system as set forth in claim 12, further comprising:

the data processing means being programmed for determining if a rate of leakage measurement occurred with air brake system actuated.

14. An air compression, storage and distribution system as set forth in claim 13, further comprising:

the data processing means being further programmed for developing various rates of leakage measurements including a most recent measurement rate and at least a first average including a contribution from the most recent measurement.

15. An air compression, storage and distribution system as set forth in claim 14, further comprising:

the data processing means being further programmed for developing various rates of charging measurements including a most recent measurement and at least a first average including a contribution from the most recent measurement.

16. A method of monitoring an air compression system for a motor vehicle, comprising the steps of:

obtaining air pressure readings from an air pressure sensor located in communication with the air compression system;

developing rates of leakage and charging of the air compression system, including rate averages based, at least in part, on recently obtained developed rates of leakage and charging; and

comparing the developed rates of leakage and charging against thresholds for determining possible fault conditions in the air compression system and indicating warning to an operator should fault conditions be met.