摘要:
A device and method for testing seal tightness of a fuel tank system of a motor vehicle, wherein excess pressure is built up in the fuel tank system by an electrically operated pump and electric current consumption of the pump is compared to reference values in order to determine whether the seal tightness of the fuel tank system is sufficient, and wherein the fuel tank system includes a filler neck with a locking fuel tank cap. A control line is connected in parallel to the power supply line of the pump, the control line being guided across an electric tank cap switch, which assumes a different switch state when the filler neck is closed properly than when it is not closed properly. In at least one of these lines, an electric resistor is installed, which allows a determination of the switch state of the tank cap switch.
摘要:
An electronic circuit (10) for controlling a capacitive pressure sensor (1), which capacitive pressure sensor (1) comprises a plate electrode capacitor (C) with a capacity that varies in dependence on pressure changes exerted on a deflectable diaphragm (2) forming one plate electrode of the capacitor (C), wherein the electronic circuit (10) comprises a DC voltage source (12) being adapted to generate a DC bias-voltage (UDC) to be applied across the electrodes of the capacitor (C), an AC voltage source (13) being adapted to generate an AC voltage signal (UAC) to be applied across the electrodes of the capacitor (C) and a controller (18) being adapted to receive an output signal (OUT) of the capacitor (C) and to control the DC voltage source (12) such that the DC bias-voltage (UDC) applied to the capacitor (C) adopts a value that maintains the capacity of the capacitor (C) at a desired value.
摘要:
A compound membrane (100) for an acoustic device (200), the compound membrane (100) comprising a first layer (101) and a second layer (102), wherein a value of Young's modulus of the second layer (102) does not vary more than essentially 30% in a temperature range between essentially −20° C. and essentially +85° C.
摘要:
A MEMS transducer (10) for an audio device comprises a substrate (12), a membrane (14) attached to the substrate (12), and a back-electrode (18) attached to the substrate (12), wherein a resonant frequency of the back-electrode (18) is matched to a resonant frequency of the membrane (14). Further, a method of manufacturing a MEMS transducer (19) for an audio device comprises attaching a membrane to a substrate (12), attaching a back-electrode (18) to the substrate (12), matching a resonant frequency of the back-electrode (18) to a resonant frequency of the membrane (14).
摘要:
An electronic circuit (10) for controlling a capacitive pressure sensor (1), which capacitive pressure sensor (1) comprises a plate electrode capacitor (C) with a capacity that varies in dependence on pressure changes exerted on a deflectable diaphragm (2) forming one plate electrode of the capacitor (C), wherein the electronic circuit (10) comprises a DC voltage source (12) being adapted to generate a DC bias-voltage (UDC) to be applied across the electrodes of the capacitor (C), an AC voltage source (13) being adapted to generate an AC voltage signal (UAC) to be applied across the electrodes of the capacitor (C) and a controller (18) being adapted to receive an output signal (OUT) of the capacitor (C) and to control the DC voltage source (12) such that the DC bias-voltage (UDC) applied to the capacitor (C) adopts a value that maintains the capacity of the capacitor (C) at a desired value.
摘要:
The invention relates to a device (1) for generating a medium stream, having a chamber (4), which chamber (4) comprises chamber walls (2, 3) lying opposite one another and at least one medium opening (27, 28, 29, 30) for the medium stream, which medium stream can be generated in the chamber (4) by means of a diaphragm (5), which diaphragm (5), in an inactive operating state of the device (1), is arranged substantially untensioned in the chamber (4) between the chamber walls (2, 3) lying opposite one another, and associated with which diaphragm (5) is a drive device (6), responsive to electrical drive signals, for driving the diaphragm (5) to deform the same, the drive device (6) being designed to impose a deformation on the diaphragm (5) in an active operating state of the device (1), during which deformation the diaphragm (5) has an inner mechanical tension.
摘要:
A fast power diode with a soft switching-time response for use in a commutating branch containing a switchable semiconductor component is formed by at least three successive diffusions with p and n dopants and the heavy metal platinum, and for final incorporation of the parameters necessary for operation, the diode is irradiated with electrons.