Abstract: An electric multispark ignition system, insensitive to moisture and wet, comprises a covering structure (1) for the piezoelectric crystals block (2) and an electric insulation means with electrodes (8, 9), completely insulated for their whole length (10) and with only one limited area (11) uncovered.

Abstract: A piezoelectric transformer inverter comprises: a piezoelectric transformer for performing voltage conversion of alternating voltage applied between primary electrodes to supply to a load connected to a secondary electrode; a driving-frequency control unit for controlling load current during driving of the load by changing the driving frequency of the piezoelectric transformer; a chopper unit for chopping input voltage applied into the driving-frequency control unit at a frequency of two or more times as high as the driving frequency and for controlling an average input voltage applied into the driving frequency control unit by changing a duty ratio of the chopping operation; and a dimming unit for intermittently stopping the driving frequency control unit by intermittently stopping the operation of the chopper unit at a frequency smaller than the driving frequency of the piezoelectric transformer, wherein even during a period in which the dimming unit is intermittently stopping the chopper unit, signals havi

Abstract: Fluorescent lamp excitation circuits are provided which use a resonating piezoelectric transformer along with complementary circuit components, to efficiently convert a DC first voltage to a transformer-output AC second voltage. In the preferred embodiment of the invention, A High Displacement Piezoelectric (HDP) transformer achieves sufficiently high voltage output to "cold fire" a gas discharge lamp. The disclosed circuit may be modified using conventional electrical sub-circuitry to pre-heat the cathodes of the lamp.

Abstract: A circuit arrangement for operating a lamp has circuit input terminals for connection to a supply voltage source. An inverter is coupled to the circuit input terminals for generating an AC voltage with a frequency f from a supply voltage supplied by the supply voltage source and includes inverter output terminals. A piezotransformer has input terminals coupled to the inverter output terminals. Terminals for lamp connection are coupled to the inverter output terminals. A detector detects whether the lamp has ignited. The transformer input terminals are connected to the inverter output terminals only by means of passive components and the inverter comprises means coupled to the detector for changing the frequency f in response to the ignition of the lamp. The circuit arrangement is simple and inexpensive and need not provide a device for switching the piezotransformer out of the circuit after ignition of the lamp.

Abstract: The application of a piezoceramic resonator (PR), connected in parallel to a discharge lamp and in series to cathode filaments of a lamp, provides reliable means of preheating of cathode filaments facilitating a soft start of a fluorescent lamp. The piezoceramic resonator is a polarized piezoceramic element formed in a form of rectangular plate, disk, cylinder, etc. The linear size and shape of the PR determine the type of oscillation, electromechanical resonant frequency and frequency characteristics. The PRs with radial, contour or longitudinal oscillations are best suited for application to a piezoelectronic ballast. Piezoceramic resonators and filters as frequency-selective elements in measuring and radio communication instruments are widely used in weak alternating electrical fields, where the intensity of field does not exceed an order of volts per mm.

Abstract: The invention relates to a circuit arrangement with a piezoelectric transformer having two electrodes arranged on the primary side of the transformer and such a piezoelectric transformer itself. Piezoelectric transformers of this type are used, for example, for the power supply or control of lamps or electron tubes. For controlling such a piezoelectric transformer directly on the primary side by a most frequently available DC voltage, instead of an AC voltage as is customary, according to the invention a DC voltage source is connected to the electrodes and a switching device is provided for interrupting the supply of voltage to at least one electrode, the positions of the switching device being dependent on the state of expansion of the primary side of the transformer. The switching device is thus periodically closed and opened, the applied DC voltage is thus interrupted periodically.

Abstract: A piezoelectric transformer drives a cold cathode tube under the control of a light controller; when the cold cathode tube is radiating in a small luminous intensity range, the light controller changes the duty factor of a driving signal supplied to the piezoelectric transformer so as to adjust the cold cathode tube at a target luminous intensity, and prevents the cold cathode tube from undesirable luminous gradient; when the cold cathode tube is radiating in a large luminous intensity range, the light controller changes the frequency of the driving signal so as to adjust the cold cathode tube to a target luminous intensity, and prevents a power supply unit from undesirable frequent load variation.

Abstract: There is provided an inverter circuit for a discharge tube which does not degrade a lighting brightness of a discharge tube even if a driving frequency is increased in order to miniaturize a step-up transformer and so forth, or which does not degrade a lighting brightness of a discharge tube, this is because a voltage applying to a discharge tube is decreased even if peripheral parasitic capacitance of the discharge tube is increased. The inverter circuit for the discharge tube comprises a high frequency oscillating circuit OS and a step-up transformer for boosting an output of the OS, and the discharge tube DT is connected to a secondary side thereof.

Abstract: A circuit arrangement for operating a discharge lamp comprising an oscillator for generating a high frequency input voltage and a piezo-electric transformer with input terminals coupled to the oscillator and output terminals. A load circuit is coupled to the output terminals of the piezo-electric transformer and includes terminals for lamp connection. The load circuit comprises an adjustable capacitor which forms a very simple device for controlling the light output of the discharge lamp over a wide range.

Abstract: In a driver of a CCFL for lightening the CCFL by using a piezoelectric transformer, a current supplied from a power source or a power consumption of the CCFL is detected and the piezoelectric transformer is on-off driven at a frequency different from an operating frequency of the piezoelectric trabsformer by a pulse width modulation signal having a duty cycle ratio corresponding to the detected value. The current supplied from the power source does not exceed a predetermined value, so that a capacity of the power source can be small and thus the cost of the power source can be reduced.

Abstract: A motion activated and light sensitive multi-purpose safety light, having a housing for supporting: a motion sensor; a light emitting diode which serves as both a light source and a light detector; an electronic circuit which further comprises; a motion sensor amplifier to condition the motion signal received from the motion sensor, a driver for illuminating the light emitting diode in a flashing manner, a timer enabling the operation of the driver and a photo-amplifier providing amplification of the input signal received from the light emitting diode. A user-selected control components for providing parameters relating to the conditioning and the flash rate. A printed circuit board providing an area to mount the electrical components and electric circuit and a system power source.

Abstract: A power transformer circuit (100) includes a capacitor (120) and a resonator (140). The resonator (140) is coupled in series with the capacitor (120) and is operable to provide a substantially inductive impedance between its terminals (142,144). Resonator (140) is preferably implemented as a piezoelectric lithium niobate resonator that is operated in a thickness-shear mode. In a preferred embodiment, power transformer circuit (100) is employed as a series resonant output circuit in an electronic ballast (500) for powering at least one gas discharge lamp (30).

Abstract: An inverter power source apparatus using a piezoelectric transformer, has: variable oscillating device for oscillating a pulse signal; pulse-width changing device for changing a width of said pulse signal of said variable oscillating device; driving device for generating a driving signal on the basis of an output of said pulse-width changing device; a piezoelectric transformer which is driven by said driving signal, drives a predetermined load, and has input and output electrodes; detecting device for detecting a relationship between said driving signal and a resonance frequency of said piezoelectric transformer, and for, on the basis of a result of the detection, controlling a frequency of said oscillation signal of said variable oscillating device so that a difference between said resonance frequency and a frequency of said driving signal is substantially within a preset range; and pulse-width controlling device for, when a detection results of said detecting device shows that said difference between said r

Abstract: A booster is constructed with a piezoelectric transducer including a combination of a primary side piezoelectric element and a secondary side piezoelectric element wherein input electrodes and an output electrode are provided in the thickness direction and length direction, respectively. The booster is contained in a plug cap. The plug cap covers one end of a spark plug. Using this arrangement, a primary voltage having a natural resonance frequency of the piezoelectric element or a waveform identical to a component waveform thereof is applied from a primary voltage generator to the input electrodes. At this time, the booster directly imparts a secondary high voltage from the output electrode to the spark plug by the piezoelectric effect, to generate a spark discharge in a discharge gap of the spark plug. This ignition system can be made smaller in size and weight at a low manufacturing cost.

Abstract: An ignition apparatus for providing energy to a spark plug (601) is described including electromagnetic means (121, 103, 133, 119) having a north pole (137) and an opposing south pole (139). A piezoelectric crystal (129) is located between the north pole (137) and the opposing south pole (139). The electromagnetic means (121, 103, 133, 119) compresses the piezoelectric crystal (129), thereby causing an ignition energy to be provided from the piezoelectric crystal (129) for igniting the spark plug (601).

Abstract: A driving circuit including a single transformer drives a piezoelectric transducer and an electroluminescent lamp. The circuit is coupled to the driving circuit for limiting the peak current through the transformer.

Abstract: A spark igniter circuit is provided for igniting a flammable gas mixture in devices such as gas torches, lanterns, stoves and the like. A piezoelectric spark generator imposes a voltage on an electrically conductive circuit which is discontinuous in two locations for creating a pair of spark gaps in the circuit. The first spark gap eliminates the need of stripping insulation from a pair of wires and providing a connector therebetween and possibly enhances the effectiveness of a spark at the second spark gap for igniting the gas mixture.

Abstract: A high voltage generating device with a PZT element is disclosed. The device includes an energization control unit for generating an energization voltage, a PZT element unit for performing voltage conversion in response to an output from the energization control unit, and a load unit for receiving an output from the PZT element unit. The PZT element unit is provided with a resonating member and an electrostrictive element, and a period of an output voltage from the energization control unit is controlled so that a primary voltage from the PZT element unit becomes maximum at a timing when the output voltage from the energization control unit is not supplied.

Abstract: A light-emitting diode is energized by converting a mechanical energy by means of a piezoelectric element into electrical charges which are transformed in a transformer into current pulses sufficient for activating the light-emitting diode. The component parts of a device of this invention include a rotation-symmetrical housing enclosing a striking member which is spring-biased against an opening in the housing, a piezoelectric element cooperating with the striking member and having two opposite electrodes connected to a primary winding of a pulse transformer. The secondary winding of the transformer is connected to the leads of the light-emitting diode. The piezoelectric element is pressed against the compression spring of the striking member by a connection spring leading to a terminal of the primary winding. All component parts are aligned along the center axis of the housing.

Abstract: Methods and apparatus for electronically igniting gas discharge lamps, such as hot- or cold-cathode fluorescent lamps, various high-pressure, metal-gas, and halogen-gas lamps.The initial heater current, in the case of hot-cathode lamps, or the initial high voltage across the unignited lamp, in the case of cold-cathode lamps, is used to heat a positive temperature coefficient resistor. The heat generated by this resistor causes a striker mechanism, consisting in essence of a pre-tensioned bi-metal disc or strip, to buckle, the said buckling striking a piezo-electric crystal, thereby inducing a high voltage, which ignites the lamp.Various coupling circuits between the mechanism and the lamp are described.The important features, compared to presently known igniters relate to the flickerless and reliable ignition of the lamp, more reliable igniter structure, and lengthened life time of the lamps.

Abstract: An electronic flash unit for igniting a gas discharge flash lamp by means of a piezoelectric element. The unit input terminals are interconnected by a series circuit comprising a rectifier and an undercritically damped parallel LC circuit. The lamp starting electrode is coupled to one main electrode via the inductor (L) and exclusive of the rectifier. The unit produces a lamp ignition signal consisting of a pulse train of alternating polarity which provides more reliable ignition of the flash lamp.

Abstract: An electronic flash unit for use with a flash-trigger mechanism having a piezoelectric generator. An RF coil or inductor interconnects the piezo crystal and flash-trigger electrode and operates to modify the energy distribution of the piezo output pulse so as to more reliably fire the flashtube for a given amount of charge on the flash unit firing capacitor.