摘要:
The invention relates to a sensor with integrated signal preconditioning and switching amplifier, whose switching point variably adjusts to slow variations in the output level of the sensor, in order to compensate for the slow influences of temperature and humidity on the sensor and to adjust the switching behavior to external conditions. For this, the invention uses a system for locking the control values to the switching threshold, obtained from the integrated sensor signal.
摘要:
The present invention relates to a device for indicating toxic substances in air that is supplied to accommodation used for personnel, preferably the cab of a motor vehicle, this having error compensation for humidity and temperature in one or a plurality of semiconductor gas sensors that are used, in which connection the sensor heating voltage is controlled to provide constant heating output and the sensor temperature pick up as well as the necessary amplifier (control stage) used to generate the temperature-varied heating voltage are arranged in a common housing, and that in the area of the sensors this housing is perforated. In order to permit compensation of the toxic substance, temperature, and humidity correlated output signals that are picked up, the present invention proposes that the characteristic curves of the sensor are reproduced in a voltage divider which, outside the sensor and jointly with the sensor forms a voltage divider for a common supply voltage, such that the influence factors compensate each other in equal proportional changes in value of both the sensor and of the outside wiring.
摘要:
A circuit for the evaluation of a signal produced by a semiconductor gas sensor provides a reliable control for manipulating a recirculated air valve in motor vehicles and their air-conditioning systems and includes a voltage divider connected with an integrator having a time constant bigger than time needed for reaching a peak of noxious gases outside of the motor vehicle.
摘要:
The present invention relates to a process for indicating toxic substances in air that is supplied to accommodation used for personnel, preferably the cab of a motor vehicle, this having error compensation for humidity and temperature in one or a plurality of semiconductor gas sensors that are used, in which connection the sensor heating voltage is controlled to provide constant heating output and the sensor temperature pick up as well as the necessary amplifier (control stage) used to generate the temperature-varied heating voltage are arranged in a common housing, and that in the area of the sensors this housing is perforated. In order to permit compensation of the toxic substance, temperature, and humidity correlated output signals that are picked up, the present invention proposes that the characteristics curves of the sensor are reproduced in a voltage divider which, outside the sensor and jointly with the sensor forms a voltage divider for a common supply voltage, such that the influence factors compensate each other in equal proportional changes in value of both the sensor and of the outside wiring.
摘要:
A motor vehicle ventilation system having a recirculation or air input mode in which when the rate of change of a signal from an outdoor gas pollution sensor exceeds a threshold limit, the system is adjusted to the recirculation mode.
摘要:
A device and method for detecting oxidizable and/or reducible gases in the air for controlling ventilation plants in buildings or motor vehicles and for monitoring combustion processes or waste gas analysis by a capacitance sensor that detects change in sensor capacities at two different frequencies. Alternating currents having at least two frequencies is passed through a heated sensor between contact electrodes of the sensor and a polycrystalline metal oxide sensor material and an evaluation circuit measures a change in capacitance between the electrodes and sensor material. A change in capacitance measured at a first frequency indicates the presence of reducible gases while a change in sensor capacitance at a second frequency indicates the presence of oxidizable gases. Variations in sensor ohmic resistance at the two frequencies are also considered.
摘要:
A pair of pollution sensors which react oppositely to exposure to respective different pollutants are connected together in one or more voltage-divider circuits so that a combined output voltage always becomes either more negative or more positive regardless of which sensor is responding to the presence of the respective pollutant. For example, a tin-dioxide sensor for gasoline exhaust and a tungsten-trioxide sensor for diesel exhaust can be connected in series as a voltage divider with a center tap connected to an evaluating circuit.
摘要:
The invention relates to a water faucet fixture (1, 1', 1"), especially for institutional kitchens and medical establishments, whereby a hot water line and a cold water line (3, 4) open into a mixing and shut-off unit (2) with a lever for manual control, by means of which water is supplied at a certain mixed temperature and flow volume to a spout (6), whereby the water faucet fixture (1, 1', 1") comprises another feed line (5) which, while bypassing the mixing and the shut-off unit (2), allows the supply of water from at least the cold water line (3) into the spout (6). This feed line (5) can be shut off by means of an electrically actuatable valve (9) that is controlled by the sensor signal of a proximity sensor (7, 7', 7"). The proximity sensor (7, 7', 7") is located in the upper area of the fixture in such a manner that movements that serve to operate the fixture manually do not fall within its detection range (20, 20', 20"). This makes it possible to operate the fixture contact-free as well as manually. Advantageously, the fixture comprises two additional sensors (15, 16) that serve to regulate the temperature contact-free.
摘要:
A gas sensor arrangement has at least a first sensor element which is primarily sensitive towards oxidizable gases and generates a corresponding measuring signal and an electric control and evaluation unit, wherein the measuring signal generated by the first sensor element is evaluated. In order to avoid inaccuracies when in addition to the oxidizable gases at the same time also reducible gases are present, the gas sensor arrangement is provided with at least one second sensor element, which is primarily sensitive to reducible gases and generates a corresponding measuring signal, which is fed to the control and evaluation unit for evaluation.
摘要:
The previously presented teaching of the invention describes a method for the evaluation of sensor signals with the purpose of producing plausible and physiologically satisfying switching impulses for interrupting or for opening the air supply in ventilation systems, particularly for the ventilation of passenger cabins in motor vehicles, depending on the pollutant content of the ambient air established by one or more sensors.