Device and method for preventing rollback of a vehicle on an incline

• US 6,814,414 B1
• Filed: 09/30/1999
• Issued: 11/09/2004
• Est. Priority Date: 09/30/1998
• Status: Expired due to Term

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Koch, Matthäus, Schmitt, Johannes
• Primary Examiner(s): Butler, Douglas C.
• Assistant Examiner(s): KING, BRADLEY T
• Application Number:
  US09/409,583
• Time in Patent Office: 1,867 Days
• Field of Search: 303/191, 303/192, 303/198, 303/186, 303/9.62, 303/9.69, 303/9.67, 303/9.68, 303/9.71, 303/9.63, 303/21.1, 303/113.5, 188/DIG.2
• US Class Current: 303/191
• CPC Class Codes: B60T 2201/06 Hill holder; Start aid systems on inclined road
• CPC Class Codes: B60T 7/122 for locking of reverse movement
• CPC Class Codes: B60T 8/172 Determining control parameters used in the regulation, e.g. by calculations involving measured or detected parameters B60T8/17551 takes precedence
• CPC Class Codes: B60T 8/245 Longitudinal vehicle inclination
• CPC Class Codes: B60T 8/266 using valves or actuators with external control means B60T8/261 takes precedence
• CPC Class Codes: B60W 30/18118 Hill holding
• CPC Class Codes: Y10S 188/02 Hill holder

Abstract

A device for preventing a rollback of a vehicle on an incline. The vehicle is equipped with a brake system, via which at least the braking pressure in the wheel brakes of a rear wheel is influenced in order to distribute the braking action between at least one front wheel and one rear wheel by actuating actuators assigned to the rear wheels so that a differential is set between the pressure of the front wheel and the rear wheel (e.g., an EBD braking). The device has a first arrangement for determining whether vehicle standstill is occurring due to braking where a differential in the braking pressure of the front wheel and the rear wheel has been set. The device also includes a second arrangement for determining whether the vehicle is rolling back from a standstill. If the second arrangement detects a vehicle rollback, the braking pressure in at least one rear wheel is increased to inhibit rollback.

Claims

1. A device for preventing a rollback of a vehicle on an incline, the vehicle including a brake system, at least one front wheel and at least one rear wheel, the brake system being utilized for influencing a first braking pressure in a first wheel brake of the at least one rear wheel to distribute a braking action between the at least one front wheel and the at least one rear wheel, the braking action being distributed by actuating actuators assigned to the at least one rear wheel so that a differential is set between a second braking pressure in a second wheel brake of the at least one front wheel and the first braking pressure in the first wheel brake of the at least one rear wheel, the device comprising:

a first arrangement determining whether the vehicle is at a standstill due to the braking action in which the differential between the first braking pressure and the second braking pressure has been set;

a second arrangement determining whether the vehicle is rolling back from the standstill, and increasing the first braking pressure in the first wheel brake of the at least one rear wheel to inhibit the rollback of the vehicle if the rollback is detected;

a sensor arrangement generating at least one wheel rotational speed signal which is associated with a rotation of the at least one front wheel and the at least one rear wheel, the sensor arrangement being assigned to the front and rear wheels;

a third arrangement determining a velocity quantity as a function of the at least one wheel rotational speed signal, the velocity quantity being indicative of a velocity of the vehicle, the first arrangement evaluating the velocity quantity for detecting the standstill; and

a fourth arrangement detecting at least one wheel speed quantity as a function of the at least one wheel rotational speed signal, the at least one wheel speed quantity being indicative of wheel speeds of individual wheels of the front and rear wheels, the second arrangement evaluating the at least one wheel speed quantity for detecting the rollback;

wherein the rollback occurs when the at least one wheel speed quantity of the at least one front wheel is equal to or less than a second predefinable comparison value, and the at least one wheel speed quantity of the at least one rear wheel is greater than the second predefinable comparison value.

2. A device for preventing a rollback of a vehicle on an incline, the vehicle including a brake system, at least one front wheel and at least one rear wheel, the brake system being utilized for influencing a first braking pressure in a first wheel brake of the at least one rear wheel to distribute a braking action between the at least one front wheel and the at least one rear wheel, the braking action being distributed by actuating actuators assigned to the at least one rear wheel so that a differential is set between a second braking pressure in a second wheel brake of the at least one front wheel and the first braking pressure in the first wheel brake of the at least one rear wheel, the device comprising:

a first arrangement determining whether the vehicle is at a standstill due to the braking action in which the differential between the first braking pressure and the second braking pressure has been set;

a second arrangement determining whether the vehicle is rolling back from the standstill, and increasing the first braking pressure in the first wheel brake of the at least one rear wheel to inhibit the rollback of the vehicle if the rollback is detected;

a sensor arrangement generating at least one wheel rotational speed signal which is associated with a rotation of the at least one front wheel and the at least one rear wheel, the sensor arrangement being assigned to the front and rear wheels;

a third arrangement determining a velocity quantity as a function of the at least one wheel rotational speed signal, the velocity quantity being indicative of a velocity of the vehicle, the first arrangement evaluating the velocity quantity for detecting the standstill; and

a fourth arrangement determining at least one detection quantity for the individual wheels as a function of the at least one wheel rotational speed signal, wherein the at least one wheel rotational speed signal alternates between a first signal value and a second signal value as a function of rotation characteristics of a respective wheel of the front and rear wheels, the at least one detection quantity being indicative of an alternation of the at least one wheel rotational speed signal between the first signal value and the second signal value, wherein the at least one detection quantity is evaluated in at least one of;

the first arrangement to detect the standstill, and

the second arrangement to detect the rollback;

wherein at least one of;

the standstill occurs if the velocity quantity is equal to or less than a first predefinable comparison value, and if the at least one detection quantity of the front wheels indicates that no alternation between the first signal value and the second signal value is occurring, and

the rollback occurs when the at least one detection quantity of the at least one front wheel indicates that no alternation between the first signal value and the second signal value is occurring for the at least one front wheel, and when the at least one detection quantity of one of the at least one rear wheel indicates that the alternation is occurring between the first signal value and the second signal value.

3. A device for preventing a rollback of a vehicle on an incline, the vehicle including a brake system, at least one front wheel and at least one rear wheel, the brake system being utilized for influencing a first braking pressure in a first wheel brake of the at least one rear wheel to distribute a braking action between the at least one front wheel and the at least one rear wheel, the braking action being distributed by actuating actuators assigned to the at least one rear wheel so that a differential is set between a second braking pressure in a second wheel brake of the at least one front wheel and the first braking pressure in the first wheel brake of the at least one rear wheel, the device comprising:

a first arrangement determining whether the vehicle is at a standstill due to the braking action in which the differential between the first braking pressure and the second braking pressure has been set;

a second arrangement determining whether the vehicle is rolling back from the standstill, and increasing the first braking pressure in the first wheel brake of the at least one rear wheel to inhibit the rollback of the vehicle if the rollback is detected;

a sensor arrangement generating at least one wheel rotational speed signal which is associated with a rotation of the at least one front wheel and the at least one rear wheel, the sensor arrangement being assigned to the front and rear wheels;

a third arrangement determining a velocity quantity as a function of the at least one wheel rotational speed signal, the velocity quantity being indicative of a velocity of the vehicle, the first arrangement evaluating the velocity quantity for detecting the standstill; and

a fourth arrangement determining at least one detection quantity for the individual wheels as a function of the at least one wheel rotational speed signal, wherein the at least one wheel rotational speed signal alternates between a first signal value and a second signal value as a function of rotation characteristics of a respective wheel of the front and rear wheels, the at least one detection quantity being indicative of an alternation of the at least one wheel rotational speed signal between the first signal value and the second signal value, wherein the at least one detection quantity is evaluated in at least one of;

the first arrangement to detect the standstill, and

the second arrangement to detect the rollback;

wherein the rollback occurs;

when the at least one detection quantity of the at least one front wheel indicates that no alternation between the first signal value and the second signal value is occurring for the at least one front wheel, and

when the at least one detection quantity of the at least one rear wheel indicates that the alternation is occurring between the first signal value and the second signal value for two of the at least one rear wheel.