Apparatus for controlling a windscreen wiping system
US5237249A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 23, 1992 |
| Grant date | Aug 17, 1993 |
| Priority date | — |
| Expiry date | Jun 23, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S318/02
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
Apparatus is provided for controlling a windscreen wiping system. The apparatus includes a circuit arrangement which includes a microcontroller, a clock generator unit comprising a switch and a clock-pulse generator, an I/V converter, a phase-selective rectifier and an amplifier with a low-pass characteristic. The apparatus also includes an optoelectronic apparatus having IR beam transmitters for transmitting useful signals in clocked form and IR beam receivers for receiving the transmitted useful signals. The IR beams which are transmitted are influenced between the IR beam transmitters and the IR beam receivers by a liquid or solid coating on the screen, such that the signals received by IR beam receivers are varied in dependence upon the coating present on the screen. The amplifier filters out the interference quantities of the ambient light to obtain a processed useful signal. The signal received by the IR beam receivers are converted by the circuit arrangement into control signals by means of which operation of the drive motor is controlled. The IR beam receivers are provided with at least one load resistor, and the voltage drop at the at least one load resistor caused by rapi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.