DE1943994A1 - Clock drive with piezoelectric tuning fork - Google Patents

Description

Clock drive with piezoelectric tuning fork.,

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The invention relates to a frequency-stabilized clock drive, especially for small watches with battery power ο

Wristwatches of the above-mentioned type with an electromagnetic oscillator in the manner of a tuning fork to drive the anchor wheel are known that of an elaborate Spu ~; / :: " ¹ one.

The object of the invention is to provide a power-saving electrical Clock drive, especially for the dimensions of a Wristwatch to indicate.

'Jie: for each task, a clock- • intx'ii.b . solved, the erfindungsgernäß characterized is that a piezoelectrically driven tuning fork with a mechanism connected to it * for the transmission of a Proportion of:; dor ochwingungsenorgie provided on a gear is where ijüi diu tuning fork the electrical 3 oscillating circuit of a Oscillator ^ in a circuit in the manner of a Vöratärkers in Uarlin .- 'ton-ochul tion or in a circuit with a peIdeffekt tranuiutor forms.,

In particular, the tuning fork has metal prongs .. Vortoilhafterv; ei.'iü if a metal is used for this purpose, a tumperaturkompensierte o oscillation behavior aufweiüta AIa

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However, the prongs can also be used in the principle "bekaraiteia bimorphs, each consisting of two ceramic strips connected to one another, which are either polarized to one another in different directions, or are electrically excited to one another when they are polarized opposite one another".

The following ffoerlegiongen led to the invention: Compared to the principle of the electromagnetiscketi a setting, the piezoelectric is more power-saving because practically any loss of heat is avoided. Represents capacitance, essentially only the capacitive current flows. The small additional active part of the current, apart from the inevitable loss of Sehwiaagoiigs energy even with the electromagnetically driven tuning fork, is practically completely converted into mechanical drive energy Piezoelectrically driven tuning fork as a resonant circuit of an oscillator, switched according to the principle »Darlington amplifier or with a field effect transistor · - resistance off. By choosing these circuits, a particularly good adaptation to the very high-pitched (some .M Γϊ j pin fork described here!

Further details of the invention will become apparent from the figures, and the description - ^r u a particularly preferred Ausfiihrungsbeiapiel out "

Figure 1 shows a piezoelectrically driven tuning fork with the metal prongs 1 and 2 and your WnE 3, with 4 are

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on the side surfaces of the prongs attached to plates made of a piezoelectric ceramic referred to. You are in essentially in the area of the greatest bend in the prongs 5 are electrode coatings on the ceramic, which are arranged so that an electrical voltage between These electrodes and the prongs 1, 2 enable an electric field to occur in the ceramic 4. 6, 7 and are electrical supply lines for connecting the electrical voltages.

With 11 attached to the prong 1 pawl 11 is referred to, which engages in a gear 12 = when starting the The tuning fork transmits the oscillation of the prong 1 to the wheel 12, which advances by one tooth with each oscillation stroke will. In particular, a thin spring leaf is used as the pawl provided that can absorb the thrust and transmit it to the wheel "

Figure 2 shows the electrical circuit diagram of the Darlington oscillator for a tuning fork as shown in Fig. 1, the same in the circuit by electrical oscillation " circles 21 and 22 corresponding to the mechanical partial oscillators 1,4 and 5 and 2,4_u.5 of the tuning fork are designated o 16, 17 and 18 are the terminals 6, 7 and 8 corresponding to Points of the 'circuit. 23 and 24 are tandem connected transistors and 25 are electrical resistors that are dimensioned in a manner known in principle so that they affect the transistors and the electrical values of the equivalent circuits the mechanical partial oscillators are dimensioned in a coordinated manner. 26 is the connection for the electrical DC voltage to supply the oscillator with electrical Energy ο

Figure 3 shows the proper to the invention circuit diagram for the tuning fork in a circuit having a field effect transistor 3'J · The remaining elements 21, 22 and 25 and points 16, V (18 entaprechen mutatis mutandis ^ ue ^ dye * giin |. Guidance according to FIG _o 2 "

ORIGINAL INSPECTBD

Claims (1)

Frequently stabilized clock drive, especially for small clocks with battery power, characterized in that a piezoelectrically driven tuning fork ν ',' I »2,3,4,5) with a mechanism (11) connected to it for transferring a portion of the vibration energy to a Gear (12) is provided, wherein the tuning fork the electrical oscillating circuits (21,22). a Darlington pair oscillator (Fig. 2) Frequency stabilized clock drive, especially for Small clocks with battery feed, characterized in that a piezoelectrically driven Tuning fork (1, 2, 3, 4, 5) with an attached mechanism (11) for transferring a portion of the Schwin * - energy is provided on a gear (12), the tuning fork the electrical oscillating circuits (21,22) an oscillator with a field effect transistor (Fig. 3) forms » Frequency-stabilized clock drive according to Claim 1 or 2, characterized in that the Mechanism a latch attached to the drive tine is ο Frequency-stabilized clock drive according to claim 3, characterized in that a thin i'ec'er leaf is provided as the ridge ο 1098 11 / 09A2 . ORiQINAL INSPECTSD