Method of controlling a wiper motor

• US 6,825,629 B2
• Filed: 03/14/2003
• Issued: 11/30/2004
• Est. Priority Date: 04/26/2000
• Status: Expired due to Fees

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Herrmann, Wolfgang
• Primary Examiner(s): Gibson, Randy W.
• Assistant Examiner(s): Santana, Eduardo Colon
• Application Number:
  US10/258,297
• Publication Number:
  US 20030169008A1
• Time in Patent Office: 627 Days
• Field of Search: 318/443, 318/444, 318/445, 318/465, 318/483, 318/DIG.2, 152/500.01, 152/501.2, 152/501.3, 152/501.6, 340/602, 340/604, 340/438
• US Class Current: 318/483
• CPC Class Codes: B60S 1/0818 including control systems responsive to external conditions, e.g. by detection of moisture, dirt or the like
• CPC Class Codes: Y10S 318/02 Windshield wiper controls

Abstract

A method and a device for controlling a wiper motor of a motor vehicle. A rain sensor sends signals to a control device and the wiper motor is switched off when a first threshold is exceeded or is not reached. After a defined time period after switching off the wiper motor, the wiper motor is switched on in order to remove residual wetness when the signals exceed or drop below a lower, second threshold.

Claims

1. A method of controlling a wiper motor of a motor vehicle, comprising:

transmitting a signal from a rain sensor to a control device;

determining an ambient brightness using a brightness sensor;

switching off the wiper motor if the signal satisfies a first threshold condition;

switching on the wiper motor to remove a residual wetness after a defined time period for which the wiper motor is switched off;

switching on the wiper motor at a defined change in the ambient brightness when the wiper motor has already be actuated at least before a predeterminable time period;

wherein the wiper motor is switched on in the switching steps only when a moisture threshold of the rain sensor satisfies a second threshold condition.

2. The method according to claim 1, wherein:

the wiper motor is switched on after the defined time period only when the signal satisfies a third threshold condition.

3. The method according to claim 2, wherein the third threshold condition corresponds to the signal exceeding a second threshold, the second threshold lower than a first threshold of the first threshold condition.

4. The method according to claim 2, wherein the third threshold condition corresponds to the signal dropping below a second threshold, the second threshold lower than a first threshold of the first threshold condition.

5. The method according to claim 1, wherein:

the wiper motor is switched on the switching step for a single wiper cycle.

6. The method according to claim 1, wherein the first threshold condition corresponds to the signal exceeding a first threshold.

7. The method according to claim 1, wherein the first threshold condition corresponds to the signal falling below a first threshold.

8. The method according to claim 1, wherein the second threshold condition corresponds to a moisture threshold of the rain sensor being exceeded.

9. The method according to claim 1, wherein the second threshold condition corresponds to a moisture threshold of the rain sensor being not reached.

10. A device for controlling a wiper motor, comprising:

a rain sensor that transmits a signal;

a timer; and

a trigger stage that switches on the wiper motor, the wiper motor having been switched off after the signal satisfies a first threshold condition, after a defined time period, to remove a residual wetness;

wherein;

the trigger stage is configured to switch on the wiper motor after the defined time only when the signal satisfies a second threshold condition, a second threshold of the second threshold condition lower than a first threshold of the first threshold condition; and

the trigger stage includes a first threshold value analyzer that compares the signal to the first threshold condition, the threshold value analyzer being connected, via a delay element connected to the timer, to a second threshold value analyzer that compares the signal to the second threshold condition and triggers a single wiper cycle when the signal satisfies the second threshold condition.

11. The device according to claim 10, further comprising:

a brightness sensor;

wherein the trigger stage actuates the wiper motor at a defined change in brightness when the wiper motor has already been actuated at least before a predetermined time period.

12. The device according to claim 11, wherein:

the trigger stage actuates the wiper motor for only one wiper cycle.

13. The device according to claim 11, wherein:

the trigger stag includes a brightness analysis stage that compares a change in a signal from the brightness sensor to a defined change in brightness.

14. The device according to claim 10, wherein:

one of the timer and the delay element includes a flag indicating a wiper cycle which is reset only after a predetermined time period has elapsed.

15. The device according to claim 14, wherein:

the trigger stage is configured to trigger a single wiper cycle for removing a residual wetness when a defined change in ambient brightness satisfies a predetermined condition and the flag is set.

16. The device according to claim 15, wherein the predetermined condition corresponds to the defined change in the ambient brightness being exceeded.

17. The device according to claim 15, wherein the predetermined condition corresponds to the defined change in ambient brightness being not reached.

18. The device according to claim 10, wherein the first threshold condition corresponds to the signal exceeding a first threshold.

19. The device according to claim 10, wherein the first threshold condition corresponds to the signal dropping below a first threshold.

20. The device according to claim 10, wherein the second threshold condition corresponds to the signal exceeding the second threshold.

21. The device according to claim 10, wherein the second threshold condition corresponds to the signal dropping below the second threshold.