Abstract: An apparatus for driving a piezoelectrically controlled fuel injection valve includes a piezoelectric actuator having a discharging device and preferably a power MOSFET switch connected in parallel therewith. The discharging device is turned on by a monitoring device that is likewise connected in parallel with the piezoelectric actuator if an opening time of the piezoelectric actuator exceeds a predetermined monitoring time. The discharging device and the monitoring device are constructed as an integrated circuit (ASIC) and are integrated in a valve housing. A method for operating the apparatus is also provided.

Abstract: In a driving operation, a capacitive actuator is charged from a series circuit of two capacitors having a charging voltage. An actuator voltage established at the actuator is controlled to a prescribed desired value in a course of a subsequent driving operation; the same procedure occurs for further actuators.

Abstract: A power MOSFET switch is connected in parallel to a capacitive actuator for the purpose of protecting the actuator against over-voltage. The protective power MOSFET switch is rendered conductive by a supplemental circuit when the actuator voltage exceeds a predetermined threshold limit voltage or when the control circuit emits a corresponding signal.

Abstract: A device for driving at least one capacitive actuator contains two capacitors C1 and C2 connected in parallel. The two parallel-connected capacitors C1, C2 are charged to an output voltage U.sub.SNT of a voltage source SNT. The actuator is charged with a voltage U.sub.C1+C2 =2*U.sub.SNT by the capacitors, and thereafter discharged into the capacitors, which are again connected in parallel and are subsequently recharged to the output voltage U.sub.SNT of the voltage source SNT.

Abstract: A device for driving at least one capacitive actuator contains a charge capacitor C1 and a discharge capacitor C2. According to the method, the actuator is charged with a desired voltage U.sub.s by the capacitors C1+C2 connected in series, and is then discharged into the discharge capacitor C2. The charge capacitor is then recharged to a voltage U.sub.C1 =U.sub.s -U.sub.C2 by a voltage source which can be regulated.

Abstract: One or more capacitive actuators are controlled by a device that charges the actuators via a capacitor and from a switched mode power supply SMPS that operates according to the flyback converter principle. The secondary coil of the switched mode power supply functions as the charging coil and the discharging coil, i.e., it simultaneously undertakes the function of the large, heavy charging coil. This saves space and weight.

Abstract: A device and a method are provided for regulating the fuel pressure in a high-pressure accumulator. A volumetric flow regulation and a pressure regulation combine the advantages of regulation of volumetric flow and regulation of pressure with one another and thus achieve increased dynamics and higher efficiency.

Abstract: An internal combustion engine is constantly monitored for overrun mode. When the overrun mode is detected, the fuel injection to the cylinders is shut off. After the shutoff of fuel injection has been accomplished, the ignition is shut off as well, but only after the (complete) degradation of a fuel wall film in the intake tube. This increases the service life of the ignition system (ignition coil, ignition end stages, spark plugs) and reduces the consumption of electrical energy.

Abstract: A process for selective graphic representation and/or evaluation of the Doppler spectrum of objects limitedly resistant to sonic intensity, for example biological organs and tissues, by an ultrasonic process wherein a material is introduced in the examination area to be acoustically irradiated, nonlinear oscillations are produced in the examination area by irradiated ultrasonic waves and the signal is evaluated by an ultrasonic converter. Also, a circuit for carrying out the above process is disclosed.

Abstract: In the exemplary embodiments, the sound signals are converted into electrical signals, which are wirelessly transmitted to an implanted receiver, and from the latter, electric stimuli in electrode channels are brought to act on the auditory nerve. The transmission proceeds in the time division multiplex technique in such a manner that the electrical signals are subjected to a pulse modulation and are transmitted in an HF-channel. Thus, the receiver can be reduced with regard to the volume of its construction as well as with regard to its energy requirement. The disclosed method and hearing prostheses for its realization are particularly suited for attending to the needs of the extremely hard of hearing.

Abstract: In the illustrated embodiments, the signals to be transmitted are converted into electrical signals and are divided by means of filters into a plurality of frequency bands. The envelopes of the signals coming out of the filters are then employed for the modulation of tones. Finally, the original tones and the modulated tones are supplied to the hearing-impaired person as an audio signal. To this end, the disclosure provides that the original signal to be transmitted is transmitted together with the modulated tones, and that the ratio of the volumes of the original tones and those of the modulated tones is set to a ratio which is comfortable for the hearing-impaired person. The transmission of the modulated tones is at least partially interrupted for voiced sounds. Standard ear sets or implanted devices with direct electrical transmission of the signals to the auditory nerve can be employed for transmission to the hearing-impaired person.

Abstract: In an exemplary embodiment, the point of departure is that of a substitute signal system for deaf individuals which codes acoustical signals, in particular speech sound, into electrocutaneous stimulation patterns. Current pulse patterns serve as substitute signals which, via skin surface electrodes, e.g. on the forearm, bring about sensory patterns which can be interpreted as speech information. To this end, the sound signal is separated with band pass filters into e.g. twelve component signals characteristic for the recognition of speech, whose levels are converted into pulse durations, whereby the dependency of the sensation intensity upon the stimulation parameters is taken into account. The mean frequencies of the band pass filters are associated with a corresponding number of locations on the forearm (i.e. in the present example twelve). A simulation of lateral inhibition suppresses irrelevant spectral components and thus acts in a selectivity-increasing (or enhancing) fashion.

Abstract: In an exemplary embodiment, the signals to be transmitted are converted into electric signals and resolved into a multiplicity of frequency bands by means of filters. The signals coming from the filters are then employed for the modulation of tone signals. Finally, original tones are supplied to the person hard of hearing together with the modulated tones as the auditory signal. To this end, the disclosure provides that the resolution ensues into at least three frequency bands and that the frequencies of the modulated tones are adapted to the residual frequency band of the person hard of hearing and that all of the signals to be transmitted are transmitted together with the modulated tones and that the ratio of the loudness of the original tones and that of the modulated tones is set at a ratio which is useful for the person hard of hearing.