GB2284028A

GB2284028A - Parking aid with brake intervention

Info

Publication number: GB2284028A
Application number: GB9422339A
Authority: GB
Inventors: Peter Knoll; Gert Pollmann
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 1993-11-16
Filing date: 1994-11-04
Publication date: 1995-05-24
Anticipated expiration: 2014-11-04
Also published as: GB2284028B; DE4339066B4; DE4339066A1; JPH07165037A; GB9422339D0; FR2712548A1

Description

2284028 1 Parkinq aid with brake intervention

Prior art

The invention is based on a parking aid for a motor vehicle with a brake unit and with at least one sensor for detecting the distance between the motor vehicle and an obstacle according to the preamble of the main claim. A distance measuring device for motor vehicles in which an acoustic and/or visual warning signal is delivered when the vehicle arrives within a predetermined distance is already known from DE 34 20 004 Al. The driver may, however, fail to notice the visual or acoustic signal as a result of being distracted by his surroundings. He may also fail to react correctly, in spite of the warnings, so that the vehicle may come into contact with the obstacle. There is also no distance-dependent brake force regulation.

Advantages of the invention In contrast, the parking aid according to the invention for a motor vehicle which has the characterising features of the main claim provides the advantage that a brake intervention which can only be overcome by depressing the accelerator pedal further automatically takes place. It is thereby 1 2 impossible for the vehicle - for example on an incline - to automatically roll against the detected obstacle, so that damage is advantageously prevented. Parking is also simplified, since the driver no longer needs to depress the brake and accelerator pedal sensitively in order to park in the parking space. Since the vehicle is braked in accordance with the distance from the obstacle, the driver only needs to use the accelerator pedal and, if applicable, the clutch, so that manoeuvring in a parking space is also simplified.

Advantageous developments of and improvements to the parking aid presented in the main claim can be achieved as a result of the measures listed in the dependent claims. A particularly advantageous feature lies in the fact that the control unit predetermines the brake force in accordance with the distance, so that a brake force which is proportional to the distance is thus predetermined for the vehicle. In particular, the brake force increases as the distance decreases. The driver can therefore only move closer to the obstacle if he increases the drive power by depressing the accelerator pedal. If he takes his foot off the accelerator pedal, the vehicle is braked immediately and safely.

A further advantage lies in the fact that the brake intervention becomes so great at a predetermined minimum limiting distance that the vehicle movement is stopped as a result. There is thus no possibility of the vehicle coming into contact with the obstacle.

If, on the other hand, the driver wishes to move right up to an obstacle, particularly in a confined space, this can advantageously be carried out by disengaging the brake intervention. This can be effected with a simple switch, by means of which the control signal to the brake unit is interrupted.

3 The parking aid according to the invention may advantageously be connected to a control unit for anti-slip regulation (ASR), since the ASR unit already comprises the brake intervention function.

Drawings An embodiment of the invention is represented in the drawings and explained in detail in the following description. Figure 1 shows a first embodiment and Figure 2 a flow diagram.

Description of the embodiment

Figure 1 shows in diagrammatic form a motor vehicle 1, which is provided with a parking aid having two sensors 2 and a control unit 3. An acoustic and/or visual indicator 5 for delivering the distance d from an obstacle 4 is connected to the control unit 3. The motor vehicle 1 is provided with an anti-slip regulation unit 6 (ASR), by means of which the wheels 7 can be subjected to a brake intervention. The driver can control the drive force of the engine by means of an accelerator pedal 8 in order to overcome the brake force. A control line which can be interrupted by a switch 9 is provided between the control unit 3 and the anti-slip regulation unit (ASR unit) 6.

The mode of operation of this arrangement is explained in detail with reference to Figure 2. The distance measuring device 2, which is known per se, comprises, for example, two ultrasonic sensors which are mounted on the rear bumper of the motor vehicle 1 and measure the distance d from a wall W. The distance d is firstly measured at position 11 according to Figure 2. This distance is indicated at the indicator 5 according to position 12. At position 13 an interrogation takes place as to whether the switch 9 for interrupting the braking action is open or closed. If the 4 switch 9 is open, i.e. the brake intervention is disengaged, the program returns to position 11 and again measures the distance d. This then corresponds to the operating sequence of known parking aids. If, however, the switch 9 is closed, a brake force is taken, for example, from a table of a memory 21 according to position 14 and a corresponding signal is fed to the ASR unit 6, as shown by position 15. A predetermined limiting value is checked in a further interrogation at position 16. If the predetermined limiting value is not reached, the program returns to position 11, where it starts a new distance measurement d. If, however, the predetermined limiting value is reached, the vehicle is stopped, so that it cannot be moved, even if the accelerator pedal is depressed further.

Figure 3 shows the control unit 3 in diagrammatic form. The control unit 3 preferably comprises a microcomputer 20, to the input 22 of which the distance signal d is applied. The microcomputer 20 is connected to a memory 21, in which a table for the distance to brake intervention relation is stored, with the braXe forces preferably increasing as the distance d decreases, so that when a predetermined limiting value is reached the brake force becomes so strong that the vehicle cannot move any further. According to the brake force which is taken, a control signal is delivered via an output 23 of the microcomputer 20 and fed by means of the switch 9 to the ASR unit 6.

The brake intervention in the ASR unit 6 is interrupted by opening the switch 9, so that the vehicle can be moved freely.

1 Z claims 1. Parking aid for a motor vehicle with a brake unit for controlling or regulating the brake force, with at least one sensor for detecting the distance from an obstacle and with a control unit which delivers a control signal according to the detected distance, characterised in that the control unit (3) is formed to control the brake unit (6) of the motor vehicle (1), by means of the control signal, in accordance with the distance (d) of the motor vehicle (1) from the obstacle.

2. Parking aid according to claim 1, characterised in that the control unit (3) comprises a memory (21), in which values for the brake force in accordance with the distance (d) are stored.

3. Parking aid according to claim 2, characterised in that the control unit (3) is formed to boost the brake force as the distance (d) decreases.

4. Parking aid according to one of the preceding claims, characterised in that the control unit (3) stops the motor vehicle movement at a predetermined minimum limiting distance.

5. Parking aid according to one of the preceding claims, characterised in that the control unit (3) comprises a switch (9) which can interrupt the control of the brake unit (6).

6. Parking aid according to one of the preceding claims, characterised in that the brake unit (6) is connected with an anti-slip regulation unit (6), and that the anti-slip regulation unit (6) regulates the brake force.

i 7. A parking aid substantially as herein described with reference to the accompanying drawings 1