Koninklijke Philips Corporation N.v.

Siemens Aktiengesellschaft

U.S. Philips Corporation

Continental Automotive Gmbh

Christian Reichinger

Gerhard Diefenbach

Josef Lauter

Matthias Wendt

Harald Reiter

Olaf Such

Ralf Schmidt

Carsten Schuh

Harald Johannes Kastl

Francisco Morales Serrano

Andras Montvay

Hans Steinbusch

Hong Zhang

Gereon Vogtmeier

Maximilian H Kronberger

Claus Zumstrull

Christoph Hamann

Walter Schrod

Hans-Jörg Wiehoff

Horst H Rumpf

Christian Hopf

Stefan Kohn

Michael Denzler

Michael Perkuhn

Franz-Josef K&uuml;ppers

Norbert Dettmann

In a method for calibration, a piezo-actuator () is actuated in a motor vehicle by a control circuit and an output stage. The piezo actuator is, in particular, part of the injection valve. The piezo-actuator () is subjected to an electric calibration pulse that is in the high-level signal range thereof when the control circuit and the output stage are in operation, the frequency thereof being modified over time. The associated electric impendence curve over the frequency is determined and evaluated during the calibration pulse. The output stage is controlled by the control circuit in such a manner that the calibration pulse is generated.

Method and device for the calibration a piezo-actuator that is actuated in a motor vehicle for driving a switching valve

In a discharge process of the solid body actuator (), a current that discharges the solid body actuator () loaded with electrical energy is detected. A switching element () is switched from an open position to a closed position to short circuit the solid body actuator () for removal of electrical energy from the solid body actuator () through the switching element () depending on the current falling below a threshold of the current, wherein the magnitude of the threshold is specified.

Method and device for controlling a solid body actuator

A piezoelectric component with a monolithic stack, has electrode layers and piezoceramic layers arranged alternately one on top of the other, the piezoceramic layers have a piezoceramic, and having at least one porous security layer arranged in the stack for the formation of a crack if mechanical overload of the stack should occur. The piezoelectric component has an infiltration barrier arranged between the security layer and a lateral surface section of the stack for suppressing the penetration of a foreign substance into the security layer. The piezoelectric component can be as a piezoactuator for controlling a valve, particularly a valve of an internal combustion engine.

Piezoelectric component comprising a security layer and an infiltration barrier and a method for the production thereof

In a piezoelectric multilayer actuator () having micromechanical relief zones () and an insulation layer () as well as in a method for producing said actuator, as a result of the micromechanical relief zones (), poling cracks are concentrated in these relief regions (). This makes it possible to provide the sections I, II, III of the multilayer actuator () with an insulation layer () which only has an extension behavior similar to the multilayer actuator () without poling cracks.

Piezoceramic multilayer actuator with stress relief sections and insulation layers in sections without relief zones

A system for monitoring a physiological condition of an individual. The system () comprises sensing means () arranged to pick up a first signal (M) in a first mode of the system, said first signal being representative of the physiological condition and to forward the first signal to a signal processing unit (). The system comprises an actuatable control unit () positioned remote from the signal processing unit, the control unit () being suitable to generate a second signal (T) arranged to be superimposed on the first signal (M). The signal processing unit () is arranged to decode the second signal and to make the system enter into a second mode upon receipt of the second signal (T).

Power saving uplink for biosensors

The system () according to the invention is arranged to support an automatic informing of callers (S, S, . . . , SN) upon an event of an interrupt in a telecommunication line engaged with a receiving station () according to a telecommunication protocol. In order to carry out said automatic informing the receiving station () is adapted with a computer program () arranged to transmit a prerecorded message to all engaged parties upon an event of the interrupt. The computer program is further arranged to carry out background interaction with a caller who is put on hold, so that the caller is not left behind unattended.

Telematic system with an automatic reconnection support

A starting-process controller for starting a piezomotor, having a voltage-controlled oscillator, a power output stage, and a resonant converter. The oscillator generates the control signals required for the power output stage and the resonance converter converts the stepped output voltage from the power output stage into a sinusoidal voltage at the output. The resonance converter drives the piezomotor with the voltage. The motor current that flows when the piezomotor is driven is measured and compared with the phase of the drive voltage in a phase comparator. The comparison output signal is a measure of the phase difference at the time between current and voltage. A phase-locked loop filter smoothes the phase-difference signal for controling the oscillator. The controller includes a start-assisting circuit element that fixes the output voltage from the phase-locked loop filter at start-up and thus applies a constant voltage to the input of the voltage-controlled oscillator.

Starting-process controller for starting a piezomotor

The invention relates to a wearable device arranged for enabling a bioelectrical interaction with an individual when being brought into contact with the individual's skin I, said device comprising electrodesarranged to carry out said interaction by means of a first electrical signal, said electrodes comprise motion artifact detection meansThe electrode assemblycomprises electrodearranged to carry out a bioelectrical interaction with the individual by means of measuring an electrical signal on the body of the individual I and/or applying an electrical signal to the body of the individual. In order to enable said bioelectrical interaction the electrodeis provided with an electrical cableAccording to the invention, the electrodeis arranged with a prThe pressure sensoris arranged to measure a normal force component of an external force applied to the electrode due to movement of the individual. Preferably the pressure sensoris a force/pressure sensitive resistor or a capacitive pressure sensor. The pressure sensor is arranged to produce an electrical signal, referred to as the second signal, the magnitude of the second signal being proportional to the pressure load. The pressure sensoris arranged with cablesfor purposes of signal proce

Wearable device for bioelectrical interaction with motion artifact correction means

A piezoelectric driving device and a regulation method for a piezoelectric driving device are proposed. Piezoelectric driving devices known so far show a characteristic with which the electric power applied to the motor drops when the load increases. This behavior, which leads to a strong reduction of the range of use of such motors, is counteracted by predefining the amplitude of the excitation voltage so that the effective power does not drop with increasing load. For this purpose the electrical effective power is determined from the excitation voltage and the current flowing through the piezoelectric resonator. Alternatively, with a predefined fixed phase angle between excitation voltage and current a regulation may also be effected in the way that the current is kept to the constant value. A further aspect of the invention relates to a unit for limiting the current flowing through the piezoelectric resonator, so as to avoid this component being damaged.

Piezoelectric driving device and a regulation method for a piezoelectric driving device

The invention relates to an inserting and extracting device for rotatable data carrier plates which mechanically moves the data carrier plate () from an inserting position into a playing position before playing and back into the inserting position again after playing, with parallel guide rails () which extend over the full range of movement for insertion and extraction and which guide the data carrier plate () in grooves () at diagonally mutually opposed edge regions, wherein at least one of the guide rails () transmits to the data carrier plate () motion pulses in one of its directions of movement, by means of which pulses the data carrier plate () is moved in the insertion or extraction direction.

Inserting and extracting device for rotatable data carrier plates

The invention relates to a piezoelectric drive device with a bimodal piezoelectric resonator, with at least a first control electrode for triggering the resonator in a first drive direction, with at least a second control electrode for triggering the resonator in a second drive direction, and with a trigger circuit for supplying control signals to the first and the second control electrode. The invention is characterized in that a regulating circuit is provided for regulating the control signals, the second control electrode is designed for supplying a feedback signal to the regulating circuit when the resonator is being triggered in the first drive direction by means of the first control electrode, and the first control electrode is designed for supplying a feedback signal to the regulating circuit when the resonator is being triggered in the second drive direction by means of the second control electrode.

Piezoelectric drive device

The invention relates to a piezoelectric actuator ( ) for driving a movable part ( ), for example a rotor, having an elongate piezoelectric resonator ( ), which serves to perform longitudinal vibrations and which is acted upon by elastic means ( ), for example a spring ( ). The elastic means ( ) acts upon the piezoelectric resonator ( ) mainly in the longitudinal direction ( ) and serves to exert a force on the resonator ( ) in a direction towards the movable part ( ), the resonant frequency of the elastic means ( ) being substantially smaller than the resonant frequency of the piezoelectric resonator ( ), and the piezoelectric resonator ( ) is guided by at least one guide element ( ) in a direction perpendicular to its longitudinal direction ( ). This enables the resonator ( ) to vibrate as freely as possible, which leads to a higher efficiency.

Piezoelectric actuator

The invention relates to a motor having a cuboid piezoelectric element ( ) which carries an actuating member ( ) for transmitting a force in an actuating direction (x). In known motors the piezoelectric element ( ) is restrained by four restraining elements which are disposed in the plane of vibration (x/y plane) and which exert a preloading force on the piezoelectric element ( ) in a direction perpendicular to the actuating direction (x). However, this gives rise to a frictional force between the restraining elements and the piezoelectric element, which reduces the vibration quality and, as a consequence, the motor power. This is avoided by means of the invention, where the piezoelectric element ( ) is restrained by means of restraining elements ( ) without preloading, i.e. with maximal slidability in the directions (y, z) perpendicular to the actuating direction (x). Preferably, such a motor is used in drive apparatuses, particularly for driving the read/write unit on a pivotable arm or on a translatable slide.

Piezoelectric motor

Electrical circuit for the control of piezoelectric drives

The invention relates to a driving device for at least two rotation elements, which device comprises at least one piezoelectric driving element. The object of the invention is to provide such a driving device having a high efficiency and allowing a more flexible positioning of the rotation elements. The invention is characterized in that the piezoelectric driving element comprises a piezoelectric resonator and at least two friction elements arranged on the piezoelectric resonator and disposed opposite one another, the piezoelectric resonator with the friction elements is arranged between the two rotation elements and is restrained by means of a pre-loading force, each one of the friction elements acts upon one of the rotation elements, and electrical means for the excitation of a vibration mode of the piezoelectric resonator have been provided.

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Neutraubling, Germany

Christian Reichinger