Abstract: A device for operating a windshield wiper with an automatic wiper control. The wiping operation is optimally adapted to the wetting conditions of a windshield as soon as the automatic wiper control is turned on. This is achieved by a control stage which, during the switching on, triggers at least one initial wiping action when responding to an activation signal emitted by an input stage. Following the initial wiping action, the wiping operation takes place on the basis of the wetting conditions detected by the sensor unit.

Abstract: The invention concerns a method and an arrangement for monitoring a computing unit, such as is used, for example, in control devices. The monitoring device generates a reset signal if the supply voltage drops below a voltage level, below which a defined operation is not ensured. Following the occurrence of a reset signal, a fixedly predetermined code is compared with the content of a volatile memory unit and a signal is emitted based on the comparison result, which determines the further process sequence. A fast and secure determination of the continued optimum process sequence is obtained by continuing with the control of the operating state as it exists at the time when the reset signal occurs, provided the content of the volatile memory unit coincides with the code, whereas a new initialization is carried out if the content of the volatile memory unit deviates from the code.

Abstract: The invention relates to an apparatus for operating a windshield wiper, having a sensor device for detecting the state of wetness of a windshield, an evaluation device that receives the sensor signal and an actuating unit for the windshield wiper that can be actuated by the evaluation device to effect suitable wiping operation. Even when individual drops impact the windshield, appropriate wiping operation can be initiated during a drying phase of the windshield, because it is provided that current measured values of the sensor signal can be supplied to both the difference-initiating stage and a drop-recognition device that is provided in the evaluation device and in which the sensor signal can be evaluated with respect to individual drops using signal breaks, and that an adapted control signal can be generated by the control-signal-generating stage when a minimum signal break is detected, with which signal corresponding wiping operation can be initiated by way of the actuating unit.

Abstract: A device for operating a windshield wiper with an automatic wiper control. A fast reaction to a suddenly occurring heavy wetting event is assured without adversely affecting the sequence of intermittent wiper operation. This is achieved by an evaluation unit which has a surge detection stage that makes it possible to detect, during intermittent operation when a sensor signal falls short of a surge threshold and by triggering a control signal for at least one wiping action when the signal falls short of the surge threshold.

Abstract: A arrangement for operating a windshield wiper in a direct mode, an intermittent mode or a continuous mode, having a sensor device for detecting a degree of moisture on the windshield, an evaluation device for the sensor signal and an actuation unit for the windshield wiper. A non-disturbing smoothing of the interval times is accomplished in a simple manner in that an interval time control has a smoothing stage for the interval time with which it can be determined during which time segment of predetermined time segments within the interval time a wetting event occurs, starting from the beginning of the interval, and with which the second interval time can be shortened all the more, the earlier the time segment appears during which the wetting event occurs.

Abstract: The invention relates to an apparatus for operating a windshield wiper, having a sensor device for detecting the state of wetness of the windshield, an evaluating device that receives the sensor signal and in which an adjusting device is provided for updating a reference value, and an actuator unit for the windshield wiper that is actuated by the evaluating device for initiating a wiping process if the difference between the reference value and a current measured value exceeds a predetermined threshold value. The evaluation and analysis of an event that influences the sensor signal, such as a slow buildup on the windshield under drizzly or foggy conditions, are facilitated by the fact that the adjusting device includes at least one adjusting stage whose time constant is in an order of magnitude of one second to a few seconds, and that the reference value can be followed step-wise, taking into consideration all current measured values received at intervals of fractions of a second.

Abstract: A sensor device for detecting a wetting condition on a windshield where radiation emitted by a radiation transmitter is coupled with the windshield by a coupling element with a beam acceptance surface designed as focusing lens and where, following at least one total reflection from the windshield via a decoupling element which has a beam emission surface that is also a focusing lens. The radiation is decoupled to a radiation receiver and the axial transmitter radiation is totally reflected on a level first limiting surface, and the radiation acceptance surface has a spherical shape. The radiation transmitter is arranged such that the diverging transmitter radiation is essentially focused axis-parallel toward the first limiting surface and that the dimensions of the first limiting surface are at least big enough so that it detects the complete parallel-focused beam of rays.

Abstract: A circuit arrangement, in particular for a wiper arrangement for motor vehicle windshields, having an electric wiper motor and a step-switching unit for the wiper motor that can be actuated via a control device, and wherein at least one output of the control device that is assigned to a specific wiper speed is connected to at least one input of the step-switching unit that determines this wiper speed.A switching means (18) is parallel-connected to the outputs (20, 24) of the control device (12), by way of which a voltage source (U.sub.bat) can be connected with the inputs (22, 26) of the step-switching unit (14), which are assigned to the outputs (20, 24) of the control device (12).

Abstract: A rain sensor in which an optical effective radiation (11) is subjected to at least one total reflection in a sheet of glass (16). The effective radiation (11) coupled out of the sheet of glass (16) into a coupling-out part (22) at the end of a measuring segment (24) and possibly present interference radiation (31') impact a separating surface (25) of the coupling out part, at which surface only one of the two radiations (11, 31') is totally reflected. The separating surface (25) permits a separation of the interference radiation (31') from the effective radiation (11) before it impacts a radiation-measuring device (30). The rain sensor of the invention is particularly suited for use in motor vehicles in connection with a windshield-wiping system which is operated automatically as a function of the rain sensor.

Abstract: A sensor device for detecting the degree of wetting and/or contamination of windows, especially windshields of motor vehicles, which device has a radiation source (12) emitting a radiation into the window (10) from the inside of the window (10), and a radiation measuring device detecting the radiation reflected many times by total reflection in the window (10) between outer surface (17) and inner surface (18). A heating device (33) is arranged on at least one contact surface between the sensor device and the window (10) or in the window. As a result, the measurement path (19) of the window (10) is deliberately heated with a low energy requirement, so that no measurement impairment is to be feared as a result of condensation on the inner surface (18) of the window and a mirrored reflection surface on this inside is not necessary.

Abstract: An arrangement for operating a wiper includes a sensor for detecting a wetting state of a pane and outputting a sensor signal based thereon, an evaluator for receiving the sensor signal from the sensor, and evaluating the sensor signal, and an actuator for actuating the wiper, the actuator being actuated by the evaluator to produce one of a plurality of wiping modes, including a stage II wiping mode for heavy wetting conditions. The evaluator includes an evaluation stage for determining whether a degree of wetting corresponding to a stage II wiping condition occurs after a prolonged wiping break, for example after passing through a tunnel, and a processing stage. If a degree of wetting corresponding to a stage II wiping condition is determined to occur after a prolonged wiping break, the processing stage is actuated by the evaluation stage to cause a change-over to stage II wiping within a shorter time period than in a case where a prolonged wiping break is not present for a comparable degree of wetting.

Abstract: The invention relates to an arrangement for the automatic operation of a windshield wiper, having a sensor device for detecting the degree of moisture on a windshield, an evaluation device, and an actuation unit for the windshield wiper which is actuated by the evaluation device. The degree of moisture on the windshield can be analyzed better in that the evaluation device in has a recognition stage for recognizing drying moisture that is present on the windshield. By means of this recognition stage, whether the level of the measured values is rising as a result of the drying process can be determined from a time sequence of measured values derived from the sensor signal. In this manner, unnecessary wiping actions can be prevented.

Abstract: An apparatus for operating a windshield wiper having a sensor device for determining the state of wetness of a windshield, an evaluation device which receives the sensor signal, a dirt-recognition stage and an adjusting device for updating a reference value when dirt is present on the windshield, and an actuating unit for the windshield wiper which can be actuated by the evaluation device in order to initiate a wiping process if the difference between the reference value and a current measured value of the sensor signal exceeds a predetermined threshold value. The measured values can be evaluated by the dirt-recognition stage with respect to signal breaks of the sensor signal caused by the wiping action of the wiper across the sensor surface.

Abstract: Proposed is a device for operating a windshield wiper in the intermittent and continuous modes. To do this, at least one sensor (12) is provided, which emits signals in dependence on the coat of moisture or the amount of rain on a windshield to be cleaned, as well as an electronic control (16) for operating the windshield wiper (11) in dependence of the signal from sensor (12). The number for the sensor signals (E) per wiping interval (WP) is recorded as control signal (n) in one evaluating mechanism (14). Furthermore and depending on whether at least one threshold value (S1, S2) is exceeded or not reached by the control signal (n) or a signal (M1, M2), derived from control signals, there is a changeover between intermittent and continuous modes by means of a changeover device (21, 22).