Sensing device for detecting wetness on a glass pane

• US 6,744,371 B1
• Filed: 04/17/2002
• Issued: 06/01/2004
• Est. Priority Date: 07/17/1999
• Status: Expired due to Term

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Gille, Andreas, Meier, Hans, Schmitt, Patrick, Burkart, Manfred, Michenfelder, Gebhard, Blitzke, Henry, Hodapp, Bruno, Hog, Norbert, Pientka, Rainer
• Primary Examiner(s): La, Anh V.
• Application Number:
  US10/030,836
• Time in Patent Office: 776 Days
• Field of Search: 340/602, 340/604, 340/603, 250/574, 250/216, 250/227.25, 250/239, 250/341.8, 250/575, 250/573, 318/483, 318/DIG.2
• US Class Current: 340/602
• CPC Class Codes: B60Q 1/1423 Automatic dimming circuits, i.e. switching between high beam and low beam due to change of ambient light or light level in road traffic
• CPC Class Codes: B60Q 2300/314 Ambient light
• CPC Class Codes: B60Q 2300/337 Tunnels or bridges
• CPC Class Codes: B60Q 2300/42 oncoming vehicle
• CPC Class Codes: B60S 1/0822 characterized by the arrangement or type of detection means
• CPC Class Codes: B60S 1/0837 with a particular arrangement of the optical elements
• CPC Class Codes: B60S 1/0881 characterized by the attachment means on the windshield

Abstract

A sensor arrangement for detecting a wetting, in particular a precipitation and dirt accumulation, on a window (13) is proposed, with at least one transmitter (14) and at least one receiver (15) for the transmitter light (17) emitted by the transmitters (14), where the transmitters (14) and receivers (15) are disposed on the vertex points of an imaginary trapezoid. As a result, the external dimensions of the sensor are reduced, the ratio of sensitive area (19) and base area (18) of the sensor is improved, and a coherent sensitive area is produced, where there is also space available for a receiving element of an automatic light control.

Claims

1. A sensor arrangement for detecting a wetting, of a precipitation and/or direct accumulation on a window (13), of motor vehicles, comprising at least one transmitter (14), at least one receiver (15), and at least one optical body (10) between the window (13) and the at least one transmitter (14) and the at least one receiver (15) for a radiation emitted by the at least one transmitter (14), wherein the projections of the at least one transmitters (14) and the at least one receivers (15), by being projected onto the window (13), constitute the vertex points of a trapezoid, wherein there are two each of the at least one transmitter (14) and the at least one receiver (15), and wherein the transmitters (14) are disposed on a first parallel of the trapezoid, wherein said first parallel is at the bottom in an installed position and the receivers (15) are disposed on a secod parallel of the trapezoid, wherein said second parallel is at the top of in the installed position.

2. The sensor arrangement according to claim 1, wherein between the at least one transmitters (14) and the at least one receiver (15), the radiation is reflected at least once against a surface of the window (13), where the at least one transmitter (14) emits radiation in different directions and the reflection surfaces thus produced form an at least approximately coherent sensitive area (19).

3. The sensor arrangement according to claim 1, wherein the at least one transmitter (14) emits radiation in two directions to two receivers (15).

4. The sensor arrangement according to claim 1, wherein the at least one receiver (15) receives radiation emitted by two transmitters (14), from two directions.

5. The sensor arrangement according to claim 1, wherein the trapezoid is a symmetrical trapezoid, where the distances of the two transmitters (14) differ from the distances of the two receivers (15) so that the one distance is approximately twice the other distance.

6. The sensor arrangement according to claim 1, wherein the sensor arrangement has four measurement paths.

7. The sensor arrangement according to claim 1, wherein centers of the reflection surfaces of the radiation cones (20) of the at least one transmitter (14) in the window (13) are spaced apart from one another by an at least approximately uniform distance on a line disposed between the two parallels of the trapezoid.

8. The sensor arrangement according to claim 1, wherein the optical body (10), transmitters (14), and receivers (15) are embodied and disposed in such a way that only a single total reflection of the transmitter light (17) occurs in the window (13).

9. The sensor arrangement according to claim 1, wherein each transmitter (14) and each receiver (15) on the optical body (10) is associated with an optical element (16), wherein each optical element has several separate lenses.

10. The sensor arrangement according to claim 9, wherein the lenses transition into one another.

11. The sensor arrangement according to claim 1, wherein each transmitter (14) and each receiver (15) on the optical body (10) is associated with an optical element (16), wherein each optical element has a single lens.

12. The sensor arrangement according to claim 5, wherein one set of receiving optics (21) for an automatic light control (ALS) is disposed centrally in the optical body (10) or shifted slightly toward the a longer parallel.

13. A sensor arrangement for detecting a wetting of a precipitation and/or direct accumulation on a window (13) of motor vehicles, comprising at least one transmitter (14), at least one receiver (15), and at least one optical body (10) between the window (13) and the at least one transmitter (14) and the at least one receiver (15) for radiation emitted by the at least one transmitter (14), wherein the projections of the at least one transmitter(14) and the at least one receiver (15), by being projected onto the window (13), constitute the vertex points of a trapezoid, wherein the optical body (10), transmitters (14), and receivers (15) are embodied and disposed in such a way that only a single total reflection of the transmitter light (17) occurs in the window (13), and wherein one set of receiving optics (21) for an automatic light control (ALS) is shifted slightly toward a longer parallel.

14. The sensor arrangement according to claim 13, wherein the receiving optics (21) includes an element (23), wherein said element is formed such that it determines the total brightness in a surrounding environment of a vehicle without direction sensitivity, and wherein further elements (22) are provided, wherein said further elements determine the brightness ratio in front of the vehicle with a light facet structure.