Monitoring method and apparatus for a brake system of heavy-duty vehicles

• US 4,964,679 A
• Filed: 02/23/1989
• Issued: 10/23/1990
• Est. Priority Date: 02/23/1988
• Status: Expired due to Fees

• Current Assignee: Lucas Industries Public Limited Company Great King Street West Midlands Birmingham 19
• Original Assignee: Lucas Industries Limited (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Inventors: Rath, Heinrich-Bernhard
• Primary Examiner(s): Butler, Douglas C.
• Application Number:
  US07/314,019
• Time in Patent Office: 607 Days
• Field of Search: 303/100, 303/93, 303/20, 303/94-97, 303/102, 303/104, 303/113, 303/103, 303/109, 303/110, 303/92, 303/105, 303/112, 303/2-3, 303/DIGS. 3-4, 340/438, 340/439, 340/441, 340/442, 340/451, 73/9, 180/171, 180/179, 180/175-178, 180/197, 188/181 A, 188/11, 188/1.11, 364/426.02, 364/426.04, 364/426.05
• US Class Current: 303/146
• CPC Class Codes: B60G 2600/04 Means for informing, instructing or displaying
• CPC Class Codes: B60G 2800/012 Rolling condition
• CPC Class Codes: B60G 2800/0124 Roll-over conditions
• CPC Class Codes: B60G 2800/24 Steering, cornering
• CPC Class Codes: B60G 2800/70 Estimating or calculating vehicle parameters or state variables
• CPC Class Codes: B60G 2800/9124 Roll-over protection systems, e.g. for warning or control
• CPC Class Codes: B60G 2800/922 EBV - Electronic brake force distribution
• CPC Class Codes: B60K 31/02 including electrically actuated servomechanism including an electric control system or a servomechanism in which the vehicle velocity affecting element is actuated electrically
• CPC Class Codes: B60T 8/00 Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force by changing number of effective brake cylinders in power brake systems B60T17/10
• CPC Class Codes: B60T 8/1708 for lorries or tractor-trailer combinations
• CPC Class Codes: B60T 8/268 using the valves of an ABS, ASR or ESP system
• CPC Class Codes: F16D 2066/001 Temperature
• CPC Class Codes: F16D 66/021 using electrical detection or indication means

Abstract

A method of and an apparatus for controlling a brake system in a heavy-duty vehicle provide for continuously measuring parameters which are characteristics of the state of the vehicle, such as the velocity of the vehicle, the inclination of the roadway, the axle load, and the transverse acceleration. Furthermore, the braking capability is being monitored continuously. To that end the temperature of the brakes, their condition of wear, the state of a compressed air reservoir, and the tire pressure are measured. For any given state of the vehicle and brakes it is determined whether or not the stopping distance to be expected will be longer than a predetermined rated stopping distance. If that is so, the driver is warned and/or a reduction of the travelling speed is initiated automatically.

Claims

1. A method of monitoring a brake system in a heavy-duty vehicle, the method comprising the steps of

measuring the velocity (V) of the vehicle,

measuring the inclination (N) of the roadway,

measuring the axle load (A),

measuring the transverse acceleration (Q) of the vehicle,

measuring the temperature (T) of the brakes,

measuring the condition of wear (S) of the brakes,

measuring the condition (P) of a brake pressure source, and

measuring the tire pressure (P_R) of the tires of the vehicle, and

determining on the basis of said measured velocity (V), inclination (N), axle load (A), transverse acceleration (Q), temperature (T), wear (S), condition (P) of a brake pressure source, and tire pressure (P_R), a stopping distance (X_ist) to be expected,

comparing said stopping distance (X_ist) to be expected with a maximum permissible stopping distance (X_soll), and

generating a warning signal if said stopping distance (X_ist) to be expected exceeds said maximum permissible stopping distance (X_soll).

2. A method according to claim 1, characterized in that said maximum permissible stopping distance (X_soll) is varied in response to said measured velocity (V) of the vehicle.

3. A method according to claim 1, characterized in that the method further comprises

determining on the basis of said measured inclination (N), axle load (A), transverse acceleration (Q), temperature (T), wear (S), condition (P) of brake pressure source, and tire pressure (P_R) a maximum rated vehicle speed at which the expected stopping distance (X_ist) does not exceed the maximum permissible stopping distance (X_soll) and

indicating said maximum rated vehicle speed.