Brake system which maintains brake force distribution upon system malfunction while partially disabling anti-lock and traction slip
First Claim
1. A brake system for a vehicle comprising:
- a plurality of wheel sensors individually associated with front wheels and rear wheels of the vehicle for determining the rotational behavior of the individual wheels;
a plurality of wheel brakes individually associated with the front wheels and the rear wheels of the vehicle;
a plurality of valves for controlling pressure fluid flow to and from said wheel brakes;
means for evaluating determinations of the rotational behavior of the individual wheels to determine a vehicle reference speed and to generate braking pressure controls for said valves;
at least one of;
(a) an anti-lock control system, and(b) a traction slip control system;
means for controlling distribution of pressure fluid flow to said wheel brakes;
means for monitoring the brake system and;
(a) for at least partially disconnecting control of the brake system in response to at least one of;
(1) defects and malfunctions, and(2) control and driving situations, and(b) upon at least one of;
(1) failure of a wheel sensor, and(2) presence of an incorrect wheel sensor determination;
(i) the vehicle reference speed determination is based on the rotational behavior determinations of those wheel sensors which are intact, and(ii) both wheel brakes associated with the rear wheels are controlled synchronously when a wheel sensor associated with a rear wheel is defective, for controlling distribution of pressure fluid flow to said wheel brakes while at least limiting at least one of anti-lock control and traction slip control, and(c) when a supply voltage drops below a first predetermined limit value, but remains in excess of a second predetermined lower limit value, for controlling distribution of pressure fluid flow to said wheel brakes while at least limiting at least one of anti-lock control and traction slip control.
1 Assignment
0 Petitions
Accused Products
Abstract
A circuit for a brake system with pressure fluid distribution, anti-lock control, and traction slip control. The circuit includes circuits to monitor the brake system and to change over or disconnect the control in response to defects and/or the respective control situation or driving situation. Upon failure of any one of the sensors which sense wheel rotation behavior or one sensor per axle or in the presence of an incorrect sensor signal, the vehicle reference speed is produced on basis of the intact sensors, and an electronic brake force distribution control function is still possible, however, an anti-lock control or a traction slip control is prevented. When the defective sensor is a rear-wheel sensor, both rear wheels are controlled synchronously. Upon the occurrence of a defect or a malfunction of a hydraulic pump system or when the supply voltage drops, an electronic brake force distribution control function is possible until a defined limit value, however, an anti-lock control/traction slip control is prevented.
-
Citations
9 Claims
-
1. A brake system for a vehicle comprising:
-
a plurality of wheel sensors individually associated with front wheels and rear wheels of the vehicle for determining the rotational behavior of the individual wheels; a plurality of wheel brakes individually associated with the front wheels and the rear wheels of the vehicle; a plurality of valves for controlling pressure fluid flow to and from said wheel brakes; means for evaluating determinations of the rotational behavior of the individual wheels to determine a vehicle reference speed and to generate braking pressure controls for said valves; at least one of; (a) an anti-lock control system, and (b) a traction slip control system; means for controlling distribution of pressure fluid flow to said wheel brakes; means for monitoring the brake system and; (a) for at least partially disconnecting control of the brake system in response to at least one of; (1) defects and malfunctions, and (2) control and driving situations, and (b) upon at least one of; (1) failure of a wheel sensor, and (2) presence of an incorrect wheel sensor determination; (i) the vehicle reference speed determination is based on the rotational behavior determinations of those wheel sensors which are intact, and (ii) both wheel brakes associated with the rear wheels are controlled synchronously when a wheel sensor associated with a rear wheel is defective, for controlling distribution of pressure fluid flow to said wheel brakes while at least limiting at least one of anti-lock control and traction slip control, and (c) when a supply voltage drops below a first predetermined limit value, but remains in excess of a second predetermined lower limit value, for controlling distribution of pressure fluid flow to said wheel brakes while at least limiting at least one of anti-lock control and traction slip control. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. A brake system for a vehicle comprising:
-
a plurality of wheel sensors individually associated with front wheels and rear wheels of the vehicle for determining the rotational behavior of the individual wheels; a plurality of wheel brakes individually associated with the front wheels and the rear wheels of the vehicle; a plurality of valves for controlling pressure fluid flow to and from said wheel brakes; means for evaluating determinations of the rotational behavior of the individual wheels to determine a vehicle reference speed and to generate braking pressure controls for said valves; at least one of; (a) an anti-lock control system, and (b) a traction slip control system; means for controlling distribution of pressure fluid flow to said wheel brakes; means for monitoring the brake system and; (a) for at least partially disconnecting control of the brake system in response to at least one of; (1) defects and malfunctions, and (2) control and driving situations, and (b) upon at least one of; (1) failure of any of said front-wheel sensors and any of said rear-wheel sensors, and (2) presence of an incorrect wheel sensor determination from any of said front-wheel sensors and any of said rear-wheel sensors; (i) the vehicle reference speed determination is based on the rotational behavior determinations of those wheel sensors which are intact, and (ii) both wheel brakes associated with the rear wheels are controlled synchronously when a wheel sensor associated with a rear wheel is defective, for controlling distribution of pressure fluid flow to said wheel brakes while at least limiting at least one of anti-lock control and traction slip control, and (c) when a supply voltage drops below a first predetermined limit value, but remains in excess of a second predetermined lower limit value, for controlling distribution of pressure fluid flow to said wheel brakes while at least limiting at least one of anti-lock control and traction slip control.
-
Specification