US3718870A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Driving circuit for electro-mechanical oscillators
Assignee: TDK Micronas GmbH
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Filing: 1971-08-12
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Granted: 1973-02-27
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Expires: 1991-08-12
Abstract
Abstract This invention relates to a circuit for driving an electromechanical oscillator (balance wheels, pendula, tuning forks) in an electronic watch. In a circuit with only one coil and two transistors, a forward biased diode is provided in series with the coil which results in sparing one of two batteries.
Inventors
- 👤 H Keller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 11:14
CPC Classifications
H; H03; H03B; H03B5/00; H03B5/30; G; G04; G04C; G04C3/00; G04C3/04; G04C3/06; G04C3/065; G04C3/069
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
206 words
A circuit arrangement for driving an electro-mechanical oscillator, said oscillator including a magnet system and single coil magnetically coupled thereto, a single source of supply voltage, a drive transistor, a control transistor of complimentary conductivity type to that of said drive transistor, said single source of supply voltage having one side connected to the emitter of said drive transistor and the other side coupled to the collector of said drive transistor and the emitter of the said control transistor said coil coupled to the collector of said drive transistor, the base of said control transistor being coupled to the collector of said drive transistor, the base of said drive transistor being coupled to the collector of said control transistor wherein the improvement comprises: a diode connected in series with said coil, said diode being polarized in the forward direction of the collector current of said drive transistor; and an additional transistor, the collector of said additional transistor being connected to the common point between one end of said coil and one end of said diode, the emitter of said additional transistor being connected to the other end of said diode and the base of said additional transistor being coupled to the other end of said coil.
Claim 2
Dependent Claim
206 words
A circuit arrangement for driving an electro-mechanical oscillator, said oscillator including a magnet system and single coil magnetically coupled thereto, a single source of supply voltage, a drive transistor, a control transistor of complimentary conductivity type to that of said drive transistor, said single source of supply voltage having one side connected to the emitter of said drive transistor and the other side coupled to the collector of said drive transistor and the emitter of the said control transistor said coil coupled to the collector of said drive transistor, the base of said control transistor being coupled to the collector of said drive transistor, the base of said drive transistor being coupled to the collector of said control transistor wherein the improvement comprises: a diode connected in series with said coil, said diode being polarized in the forward direction of the collector current of said drive transistor; and an additional transistor, the collector of said additional transistor being connected to the common point between one end of said coil and one end of said diode, the emitter of said additional transistor being connected to the other end of said diode and the base of said additional transistor being coupled to the other end of said coil.
Claim 3
Dependent Claim
21 words
A circuit arrangement according to claim 1 wherein said diode is connected between said Coil and said source of supply voltage.
Claim 4
Dependent Claim
22 words
A circuit arrangement according to claim 1 wherein said diode is connected between the collector of said drive transistor and said coil.
Claim 5
Dependent Claim
17 words
A circuit arrangement according to claim 1, wherein said additional transistor is complementary to said driving transistor.
Claim 6
Dependent Claim
17 words
A circuit arrangement according to claim 1, wherein said additional transistor is complementary to said control transistor.
Claim 7
Dependent Claim
204 words
A circuit arrangement according to claim 3, wherein the emitter of said control transistor is AC coupled to said source of supply voltage and DC coupled to the common connection between said coil and said diode. In FIGS. 4 and 5 there are shown further embodiments of the inventive type of circuit arrangement serving to reduce the voltage drop of the diode D in cases where the driving transistor T1 is driven into saturation and which, when using silicon components, the voltage drop a cross diode of amounts to about 0.7 volt, and is thus only half as large as the usually employed supply voltage of about 1.35 volt. In this case the diode D is bridged by the collector-emitter path of the auxiliary transistor T3 or T4 respectively, which is connected in such a way as to be automatically driven into saturation together with the driving transistor T1. According to FIG. 4 it is provided in this connection, that the auxiliary transistor T3 is complementary to the driving transistor T1. The collector of the auxiliary transistor T3 is connected to the point connecting both the diode D and the coil L, while the emitter is applied to the source of supply voltage UB.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-02-27 | 1976-08-28 | 1977-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-27 | 1980-08-28 | 1981-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-27 | 1984-08-28 | 1985-02-27 | $7700.00 | Window Closed / Lapsed |