Process and device for operating a rain sensor

• US 6,329,923 B2
• Filed: 09/09/1999
• Issued: 12/11/2001
• Est. Priority Date: 07/08/1997
• Status: Expired due to Fees

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH GMBH
• Inventors: Hog, Norbert
• Primary Examiner(s): Lieu, Julie
• Application Number:
  US09/380,924
• Publication Number:
  US 20010038335A1
• Time in Patent Office: 824 Days
• Field of Search: 340/601, 340/602, 318/480, 318/483, 152/500.01, 152/501.2
• US Class Current: 340/601
• 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: B60S 1/0833 Optical rain sensor

Abstract

An apparatus and a method for operating a rain sensor (10) that outputs a sensor signal (18, 22) as a function of the wetting of a window (11) are proposed, having a controller (16) which as a function of the sensor signal (18, 22) outputs a control signal (28) to the rain sensor (10) for regulating the sensor signal (18, 22); for signal evaluation, the sensor signal (18, 22) and in addition the control signal (28) are used for tripping switching events of a device.

Claims

1. An apparatus for operating a rain sensor (10) which is used for automatic triggering of a device, in particular a windshield wiper for motor vehicles, having a transmitter (12), a receiver (14) whose sensor signal (18) as a function of detected moisture is delivered to a signal processor (20) and to an evaluation arrangement (34) downstream thereof, and a controller (16), which has a function of the sensor signal (18, 22) outputs a control signal (28) to the rain sensor (10), wherein in addition to outputting the control signal to the rain sensor (18, 22), the control signal (28) is also separately delivered to the evaluation arrangement (34) for tripping switching events of the device, and the controller (16) regulates a transmission power of the rain sensor (10).

2. The apparatus of claim 1, wherein the evaluation arrangement (34) is disposed spatially remotely from the rain sensor (10) and/or the controller (16), and preferably forms part of a central electronic system of a motor vehicle.

3. The apparatus of claim 1, wherein the controller (16) regulates the transmission power of the transmitter (12) continuously or in stages, in particular upon attainment of limit values for the working range of the rain sensor.

4. The apparatus of claim 1, wherein the controller (16) is constructed as an ASIC (application-specific IC).

5. The apparatus of claim 1, wherein it has a differential amplifier 30 for amplifying the sensor signal 22.

6. The apparatus of claim 1, wherein the control signals 28 or sensor signals 18, 22 delivered to the evaluation arrangement 34 are analog or digital.

7. The apparatus of claim 1, wherein it is intended for use for triggering a wiper motor (42) of a windshield wiper system.

8. A method for operating a rain sensor (10) which is used for automatic triggering of a device, in particular a windshield wiper for motor vehicles, having a transmitter (12), a receiver (14) whose sensor signal (18) as a function of detected moisture is delivered to a signal processor (20) and to an evaluation arrangement (34) downstream thereof, and a controller (16), which is a function of the sensor signal (18, 22) outputs a control signal (28) to the rain sensor (10), wherein in addition to outputting the control signal to the rain sensor (18, 22), the control signal (28) is also separately delivered to the evaluation arrangement (34) for tripping switching events of the device, and the controller (16) regulates a transmission power of the rain sensor (10).

9. The method of claim 8, wherein the evaluation arrangement (34) evaluates the control signal (28) and/or the sensor signal (18, 22).

10. A method for operating a rain sensor (10) which is used for automatic triggering of a device, in particular a windshield wiper for motor vehicles, having a transmitter (12), a receiver (14) whose sensor signal (18) is delivered to a signal processor (20) and to an evaluation arrangement (34) downstream thereof, and a controller (16), which is a function of the sensor signal (18, 22) outputs a control signal (28) to the rain sensor (10), wherein in addition to the sensor signal (18, 22), the control signal (28) is also delivered to the evaluation arrangement (34) for tripping switching events of the device, the evaluation arrangement (34) evaluates the sensor signal (18, 22) if the control signal (28) is constant, and if the control signal (28) is varying, it evaluates the control signal (28) independently of the sensor signal (18, 22) for tripping switching events of the device.