Abstract: A method for operating an electric arc furnace having at least one electrode, the method including the following steps: introducing material that is to be melted in the form of an actual mass flow into the electric arc furnace and feeding electrical energy via at least one electrode into the electric arc furnace in order to melt the introduced material depending on a previously determined, necessary electrical energy input. The necessary electrical energy input into the arc furnace is determined depending on the mass flow input into the furnace.

Abstract: A micromechanical sound transducer system includes a substrate that includes (a) a cavity with a cavity edge area, (b) a front side, and (c) a rear side; a piezoelectric vibrating beam that is elastically suspended on the front side and that extends across the cavity; and, for the piezoelectric vibrating beam, a respective deflection limiting device that is on a front edge area of the respective vibrating beam and that is configured to limit a deflection of the respective vibrating beam to a limiting deflection by causing the respective front edge area of the respective vibrating beam to interact with the cavity edge area or an opposing front edge area of another vibrating beam.

Abstract: A micromechanical sound transducer system includes a substrate that includes (a) a cavity with a cavity edge area, (b) a front side, and (c) a rear side; a piezoelectric vibrating beam that is elastically suspended on the front side and that extends across the cavity; and, for the piezoelectric vibrating beam, a respective deflection limiting device that is on a front edge area of the respective vibrating beam and that is configured to limit a deflection of the respective vibrating beam to a limiting deflection by causing the respective front edge area of the respective vibrating beam to interact with the cavity edge area or an opposing front edge area of another vibrating beam.

Abstract: Measures for regulating the electrical bias voltage at the measuring capacitor of a MEMS sensor element are described. A base voltage is applied to the measuring capacitor and regulated in such a way that the potential difference between the two electrode sides of the measuring capacitor corresponds to the setpoint voltage. The base voltage is regulated in a low-voltage range.

Abstract: A MEMS loudspeaker device and a corresponding manufacturing method are described. The MEMS loudspeaker device includes a first substrate having a first front side and a first rear side, which includes a first rear side cavity, which is at least partially covered by a sound generation device; a second substrate having a second front side and a second rear side, which includes a second rear side cavity, which is covered by a first perforated plate device; the second rear side being bonded to the first front side in such a way that the second rear side cavity is situated above the sound generation device; and a second perforated plate device, which is attached above the first perforated plate device; at least one of the first perforated plate device and of the second plate device being elastically deflectable in such a way that a passage of sound of the sound generation device may be modulated by an interaction of the first perforated plate device and the second perforated plate device.

Abstract: A method for the precise measuring operating of a micro-mechanical rotation rate sensor, including at least one seismic mass, at least one drive device for driving the seismic mass in the primary mode (q1) and at least three trimming electrode elements which are jointly associated directly or indirectly with the seismic mass. An electric trimming voltage (u1, u2, u3, u4) is set respectively between the trimming electrode elements and the seismic mass. Each of the electric trimming voltages (u1, u2, u3, u4) are adjusted in accordance with a resonance frequency variable (?T, ?T,0), a quadrature variable (?c, ?C,0) and a restoring variable (?S).

Abstract: Measures for regulating the electrical bias voltage at the measuring capacitor of a MEMS sensor element are described. A base voltage is applied to the measuring capacitor and regulated in such a way that the potential difference between the two electrode sides of the measuring capacitor corresponds to the setpoint voltage. The base voltage is regulated in a low-voltage range.

Abstract: A method for setting the dynamic range of a rotation rate sensor includes exciting a mass of the rotation rate sensor mounted such that the mass is configured to vibrate linearly using a drive signal. The drive signal is provided at a resonant frequency of the mass. The method further includes influencing the vibration by using an amplification signal. The amplification signal is provided at a multiple of the resonant frequency in order to set a dynamic range.

Abstract: In a method for operating a rotation rate sensor including a substrate and a seismic mass, the seismic mass is driven in a drive direction in parallel to the main extension plane of the sensor to carry out a drive movement, and, during a rotation of the rotation rate sensor, the seismic mass is moved in a detection direction perpendicular to the drive direction and perpendicular to the rotation rate as a result of the action of force caused by the Coriolis force. The movement in the detection direction has a deflection amplitude, and the rotation rate sensor includes a deflection support element acting on the seismic mass in such a way that the deflection amplitude in the detection direction is increased.

Abstract: A device for measuring yaw rate, having a mechanical yaw rate sensor, which has an inert mass that can be set into a primary vibration along a primary axis by means of an excitation device and can be deflected along a secondary axis extending transversely with respect to the primary axis so that when a yaw rate occurs about a sensitive axis extending transversely with respect to the primary and to the secondary axis, said device carries out a secondary vibration excited by the Coriolis force. A sensor element detects an amplitude-modulated signal for the secondary vibration. A sigma-delta modulator has a low pass filter connected to the sensor element, a quantizer and a secondary actuator disposed in a feedback path for applying a force which counteracts the Coriolis force.

Abstract: A measuring device has a micro-electromechanical capacitive sensor which has electrodes which move toward and away from each other for measurement of a mechanical deflection of a test mass. The measuring device has a charge integrator which has an operating amplifier which has at least one amplifier input connected to the sensor and an amplifier output which is fed back to the amplifier input via an integration capacitor. The amplifier input is connected via a high-resistance electrical resistor to a terminal for an electrical common-mode reference potential. In addition to the amplifier input, the operating amplifier has an auxiliary input. The amplifier output is connected to the auxiliary input via a deep pass.

Abstract: A method for the precise measuring operating of a micro-mechanical rotation rate sensor, including at least one seismic mass, at least one drive device for driving the seismic mass in the primary mode (q1) and at least three trimming electrode elements which are jointly associated directly or indirectly with the seismic mass. An electric trimming voltage (u1, u2, u3, u4) is set respectively between the trimming electrode elements and the seismic mass. Each of the electric trimming voltages (u1, u2, u3, u4) are adjusted in accordance with a resonance frequency variable (?T, ?T,0), a quadrature variable (?c, ?C,0) and a restoring variable (?S).

Abstract: A measuring device has a micro-electromechanical capacitive sensor which has electrodes which move toward and away from each other for measurement of a mechanical deflection of a test mass. The measuring device has a charge integrator which has an operating amplifier which has at least one amplifier input connected to the sensor and an amplifier output which is fed back to the amplifier input via an integration capacitor. The amplifier input is connected via a high-resistance electrical resistor to a terminal for an electrical common-mode reference potential. In addition to the amplifier input, the operating amplifier has an auxiliary input. The amplifier output is connected to the auxiliary input via a deep pass.