FR2500692A1 - ELECTRIC POWER GENERATING DEVICE - Google Patents

Abstract

THIS DEVICE CONTAINS A MECHANICAL ENERGY SOURCE, A MECHANICAL-ELECTRIC PIEZO-ELECTRIC CRYSTAL CONVERTER AND A CHARGING CIRCUIT CONNECTED TO THE ELECTRODES OF THIS CONVERTER. THIS CHARGING CIRCUIT INCLUDES THE SERIAL ASSEMBLY OF A CAPACITOR 3, A RECTIFIER 4 AND A SPARKLIST 5, A CONSUMPTION CIRCUIT 7 BEING CONNECTED TO THE CONDENSER TERMINALS. THIS DEVICE ALLOWS A CONDENSER OF RELATIVELY LARGE CAPACITY TO BE CHARGED AT SUFFICIENT VOLTAGES TO SUPPLY FOR EXAMPLE A RELATIVELY COMPLEX ELECTRONIC CIRCUIT, OR TO RELIABLY TRIGGER A DESTRUCTION DEVICE.

Description

The present invention relates to a current generator device

  electrical apparatus comprising a source of mechanical energy, a piezoelectric crystal mechano-electric converter and an electric charge circuit connected to the electrodes of this converter, wherein the charging circuit comprises the series connection of a capacitor, a a rectifier and a peaked spark gap, a consumption circuit being connected to the

capacitor terminals.

  The aim of the invention is to provide a device generating a current independent of a battery or other source of external electrical energy, thus making it possible to avoid

  disadvantages related to the usual feeding devices.

  In particular, in the case of devices that must operate after a relatively long storage or inactivity period or in the case of devices in

  which the life, price, weight and encumbrance

  The use of a battery is a significant disadvantage and the present device is an extremely interesting solution. Thus, the invention can in particular be applied to a device for triggering an explosive primer, to a device for supplying an electronic circuit such as a logic circuit or to a power supply device for a device. portable electronic device subject to mechanical actions such as shock, acceleration or deceleration

  isolated or repeated, depending on the case.

  The invention will be better understood in the light of

  following description illustrated by the attached drawing, which

  represents, by way of example, an embodiment of the

device according to the invention.

  The single figure shows schematically a piezoelectric crystal 2 contained in a capsule 1 that can be subjected to the force F of a source of mechanical energy. In series with the piezoelectric crystal are connected a capacitor 3, a diode 4 and a spark gap - 2 -

  5. Another phase 6 is connected in paral-

  to the piezoelectric crystal 2 and the spark gap 5.

  7 is connected in parallel with the condenser 3.

  The piezoelectric crystal can be of a standard type as described, for example, in the book "Piezoelectric Ceramics" edited by J. van Randeraat and N.V. Philips' Gloeilampenfabrieken, Eindhoven, 2nd edition 1974, for a

  ignition device (chapter 3, pages 23 to 39).

  According to the invention, the series connection of a

  5 and the capacitor 3, in combination with the diodes 4 and 6, collects on capacitor 3 a capacity for example of the order of 1uF, a voltage of a few volts to a few tens of volts. In some exemplary embodiments, capacitances of λF were used to collect a voltage of 10 V, or capacitances of 0.1 μF to collect a voltage of 140 V, that is,

  a quantity of energy of about 1 mJ was accumulated.

  The spark gap 5 plays a crucial role in this device, since it is not possible to charge directly from a piezoelectric crystal a capacitor of relatively large capacity at voltages sufficient to supply, for example, a relatively complex electronic circuit. .

  Diodes 4 and 6 are used to charge the condensate

  sator 3 by positive and negative current pulses. The consumption circuit 7 can be for example a high impedance electronic circuit or, in a particular case, the beginning of a detonation device or any

other suitable circuit.

  The excitation of the piezoelectric crystal 2 can for example come from an isolated shock to trigger a detonator or come from an accelerated or decelerated movement 34 of a mobile carrier of the supply device; For example, the device can be mounted on a projectile and control a security device, or it can be carried by a

  person or mounted on a vehicle.

  In all cases of application, the source of energy

  electricity has an indefinite lifespan and is

  very high operational safety.

-4-

Claims (2)

  Electrical power generating device comprising a mechanical energy source, a piezoelectric crystal mechano-electric converter (1) and an electric charge circuit connected to the electrodes of this converter, characterized in that the charging circuit comprises the series connection of a capacitor (3), a rectifier (4) and a spike arrester (5), a circuit   of consumption (7) being connected across the capacitor.   2. Device generating electric current according to claim 1, characterized in that it comprises a   two-phase rectification device (4, 6).