US3747326A - Clock drive with piezoelectric tuning fork - Google Patents
Clock drive with piezoelectric tuning fork Download PDFInfo
- Publication number
- US3747326A US3747326A US00162227A US3747326DA US3747326A US 3747326 A US3747326 A US 3747326A US 00162227 A US00162227 A US 00162227A US 3747326D A US3747326D A US 3747326DA US 3747326 A US3747326 A US 3747326A
- Authority
- US
- United States
- Prior art keywords
- tuning fork
- wheel
- oscillator
- frequency
- clock drive
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 230000010355 oscillation Effects 0.000 claims description 44
- 230000005540 biological transmission Effects 0.000 claims description 26
- 238000010168 coupling process Methods 0.000 claims description 21
- 238000005859 coupling reaction Methods 0.000 claims description 21
- 230000007246 mechanism Effects 0.000 claims description 20
- 230000008878 coupling Effects 0.000 claims description 19
- 230000006872 improvement Effects 0.000 claims description 15
- 230000033001 locomotion Effects 0.000 claims description 14
- 238000003475 lamination Methods 0.000 claims description 11
- 230000003534 oscillatory effect Effects 0.000 claims description 11
- 230000010287 polarization Effects 0.000 claims description 6
- 230000000694 effects Effects 0.000 claims description 5
- 230000009347 mechanical transmission Effects 0.000 claims description 5
- 239000002184 metal Substances 0.000 claims description 4
- 230000011664 signaling Effects 0.000 claims description 4
- 229910010293 ceramic material Inorganic materials 0.000 claims description 2
- 230000002596 correlated effect Effects 0.000 claims description 2
- 230000008901 benefit Effects 0.000 description 3
- 230000005284 excitation Effects 0.000 description 3
- 239000000919 ceramic Substances 0.000 description 2
- 230000000875 corresponding effect Effects 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000002441 reversible effect Effects 0.000 description 2
- 230000006978 adaptation Effects 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 238000013016 damping Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
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- 238000005259 measurement Methods 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G04—HOROLOGY
- G04C—ELECTROMECHANICAL CLOCKS OR WATCHES
- G04C3/00—Electromechanical clocks or watches independent of other time-pieces and in which the movement is maintained by electric means
- G04C3/08—Electromechanical clocks or watches independent of other time-pieces and in which the movement is maintained by electric means wherein movement is regulated by a mechanical oscillator other than a pendulum or balance, e.g. by a tuning fork, e.g. electrostatically
- G04C3/12—Electromechanical clocks or watches independent of other time-pieces and in which the movement is maintained by electric means wherein movement is regulated by a mechanical oscillator other than a pendulum or balance, e.g. by a tuning fork, e.g. electrostatically driven by piezoelectric means; driven by magneto-strictive means
-
- G—PHYSICS
- G04—HOROLOGY
- G04C—ELECTROMECHANICAL CLOCKS OR WATCHES
- G04C3/00—Electromechanical clocks or watches independent of other time-pieces and in which the movement is maintained by electric means
Definitions
- ABSTRACT A clock drive in which a piezoelectric tuning fork actuates the driving wheel of a clockwork includes a second tuning fork serving as a narrow-band, frequencydetermined time standard coupled with the wheelactuating tuning fork.
- CLOCK DRIVE WITH PIEZOELECTRIC TUNIN FORK This invention relates to a frequency-stabilized clock drive, and is more particularly concerned with driving force as generated by a piezoelectric tuning fork operating as an oscillator.
- a principal purpose of the present invention is to improve clock driving means especially in battery-driven smallclocks in which a piezoelectrically excitable tuning fork has a part of the resonance oscillation energy transferred by means of a transmission pawl or the like to a drive wheel by which the hands of the clock are driven through a suitable gearwork.
- An important object of the present invention is to overcome the foregoing and other disadvantages, defects, inefficiencies, shortcomings and problems in prior clock drives of this type and to attain important advantages and improvements in the operation of piezoelectric tuning fork clock drives. 7
- Another object of the invention is to provide a new and improved piezoelectric tuning fork clock driving system.
- a further object of the invention is to provide new and improved means 'for controlling the frequency constancy of a piezoelectric tuning fork oscillator in a clock drive.
- Still another object of the invention is' to provide a new and advantageous electrical clock drive attaining unusual driving ability with low battery voltage.
- Yet another object of the invention is to .provide a clock drive of the character-indicated which is unusually stable under variable temperature conditions.
- a still further object of the invention is to provide a new andimproved clock drive embodying a plurality of cooperative piezoelectric devices.
- a yetfurther object of the invention is to provide a simplified transmission of oscillatory to rotary driving movement in piezoelectric tuning fork clock drives.
- FIG. 1 is a schematic illustration representing one practical embodiment of the invention.
- FIG. 2 is a performance curve diagram.
- FIG. 1 a representative clock drive with means for maintaining frequency and oscillation amplitude constant according to the present invention.
- a tuning fork Aserving as the principal driving means has its prongs coupled vibrationally and mounted on a mounting block -I.
- the principal driving means has its prongs coupled vibrationally and mounted on a mounting block -I.
- prongs of the fork A comprise respective pairs of ceramic laminations 2 and 3 having opposite piezoelectric effect of different or opposite polarization.
- the individual laminations are switched electrically parallel, but in respect to their mechanical effect one behind the other, so that, in spite of low voltage, a great deflection results.
- the laminations may be adhesively connected, where they are superficially metallized they may be welded to each other. I
- a second, smaller tuning fork Z is provided and coupled mechanically and/or acoustically to the fork A and serves as a narrow-band, frequencydetermined time standard.
- the fork Z is desirably made of a material relatively unaffected by temperature, and more particularly made of metal, so that its resonance frequency is unaffected by temperature in contrast to the fork A which may be affected in its resonance frequency by temperature variations.
- Optimum frequency-selective properties of the tuning forks in the oscillator circuit are utilized by a preferred electrical coupling, wherein the right-hand prong of the tuning fork A, as visualized in FIG. 1, is connected in the collector circuit of a transistor Tr, while the left-hand prongof the fork A and the frequencyand amplitude-determined fork member Z and a coil S are in the base circuit of the transistor Tr and thus in the reverse-coupling branch of the oscillator.
- an inductor coil L the collector circuit of the transistor Tr is completed via the battery B in a directcurrent manner, while the working point of the transistor is adapted to be adjusted with the assistance of aresistor R.
- Coupling between the tuning fork A and the tuning fork Z is effected by means of a coupling resistance R I
- the fork Z comprising a metallic oscillator 4
- the fork Z carries on the oscillating ends of its prongs respective loading weights 5 and piezoelectric transducers 6.
- the weights 5 may serve as respective electrical connections, as shown.
- the wheel perimeter is made of a suitable wear-resistant plastic material of sufficient softness and resilience such that the driving tip of the pawl digs into the wheel perimeter when the pawl is thrust toward the wheel in the fork oscillations to thus cause the wheel to rotate a predetermined increment.
- the driving tip of the pawl digs into the wheel perimeter when the pawl is thrust toward the wheel in the fork oscillations to thus cause the wheel to rotate a predetermined increment.
- This is a substantially more economical driving coupling between the pawl and the drive wheel than a toothed arrangement of the wheel requiring a costly attachment of formation of teeth to the wheel.
- the present invention there are, further, provided means for generating electrical signals in the rotation of the drive wheel 8 fed into the oscillator in such a manner that the amplitude of the driving tuning fork A and thus the speed of rotation of the drive wheel 8 are maintained constant.
- Measurement of the speed of the drive wheel 8 applied for regulation of the oscillation amplitude is adapted to be effected without physical contact between relatively moving parts.
- the drive wheel 8 and the coil S are desirably cooperative as an alternating current generator.
- the wheel 8 is provided with electric signal producing areas 9 located equidistantly spaced along or adjacent to its circumference, equal in number with the desired oscillation frequency of the oscillator A.
- the areas 9 may be, as shown, narrow spaced radially elongated, comprising, respective magnetic layers of alternating polarity.
- the coil detects the respective area and a respective electrical impulse is effected, resulting in the induction of an electrical alternating current voltage in the coil S as the wheel 8 rotates.
- the frequency of this voltage corresponds exactly to the frequency of the time standard oscillator Z.
- the sum of the voltages which are supplied by the time standard fork Z and by the coil S is applied.
- the result is a simple regulator circuit involving switching the coil electrically in line with'the frequency-determining tuning fork Z whereby a phase-correct addition of the voltages produced in both switching elements is enabled in a simple manner.
- a field plate or similar magnetic-field responsive component may be utilized instead of a coil such as S.
- Other structuresin the signal producing areas 9 may be employed, such as piezoelectric layers of alternating polarization to produce a corresponding signal in a suitable receiver which reacts to changing electrical fields. Further, due to the electrical areas 9, a non-magnetic behavior of the clock is assured.
- Operation of the regulated clock drive is as follows.
- the right-hand prong of the driving oscillator fork A is deflected, and due to its elastic properties starts to oscillate.
- These oscillations are transferred vibrationally to the left-hand prong of the fork A by way of the mounting block 1 and produce a voltage which is transferred by means of the coupling resistor R onto the righthand prong of the time standard fork Z.
- a voltage is produced in the left piezoelectric transformer 6 which is checked against the voltage formed in the coil S, and serves the purpose of switching on and off the transistor Tr.
- the voltages are conducted in such a manner that the transistor Tr is switched on and off at the correct moment.
- the transistor Tr is not switched, and no voltage affects the drive oscillator fork A. Oscillation amplitude of the fork A and thus the speed of the wheel 8 will diminish until the phase difference has changed to the extent that the resulting reverse-coupling voltage is just sufficient to maintain the correct speed of rotation of the wheel 8. It is important that the wheel 8 have enough operational mass to bridge the delays in reaction due to the oscillator quality of the fork A. Further, it is advantageous not to provide too great resonance quality for the tuning fork A.
- FIG. 2 assists in explaining a further advantage arising from a low oscillator quality of the fork A.
- D the oscillation amplitude of the two tuning forks A and Z, in dependence on the frequency f.
- F is the narrowband excitation function of the time standard fork Z, and F is the broad-band excitation function of the tuning fork A.
- the resonance frequenciesf, of the two tuning forks coincide.
- the curve F' only a small amplitude difference occurs, represented by AD with a broadband resonance curve of the driving oscillator A, whereby this amplitude difference, depending on the temperature, is the smaller the more broad-banded the resonance curve of the driving oscillator A becomes.
- the coil S can, of course, be omitted.
- the voltage which is formed in the left-hand prong of the time standard fork Z is then directly coupled to the basic circuit of the transistor Tr.
- amplifying elements may be employed instead of the bipolar transistor Tr, such as field-effect transistors, bipolar transistors in a Darlington switch, or the like, without departing from the present invention.
- the individual voltages which are generated in the coil S or in the left prong of the time-standard fork Z may also be amplified first, if necessary. To avoid too high a cur rent consumption, skillful selection of the individual component parts should be practiced.
- a frequency-stabilized clock drive including a piezoelectric tuning fork which transfers oscillation energy by means of a mechanical transmission mechanism directly coupled therein to a drive wheel and is connected in an oscillator circuit including an electrical energy supplying battery, the improvement comprising:
- a clock drive according to claim 1, wherein said v oscillator comprises a second, smaller tuning fork made 4.
- the prongs of said tuning fork comprise laminations made of ceramic material with opposite piezoelectric effect.
- a clock drive according to claim 1, wherein one prong of the tuning fork is connected to said transmission mechanism, said oscillator comprises a smaller tuning fork, a second prong of 'said driving tuning fork being electrically coupled with one prong of said smaller tuning fork, and the remaining prong of said smaller tuning fork being coupled in the electrical circuit with said battery.
- a clock drive according to claim 1, wherein one prong of the tuning fork is connected to said transmission, said oscillator comprises a smaller tuning form, a second prong of said driving tuning fork being electrically coupled with one prong of said smaller tuning fork, an alternating current generator including said wheel and a coil, and said coil being connected at one end in said electrical circuit with said battery and at its opposite end connected with the remaining prong of said smaller tuning fork.
- a clock drive including an alternating current generator comprising said wheel and a coil, and means electrically connecting said coil with said oscillator.
- a clock drive according to claim 9 said wheel having circumferentially spaced signal producingareas numerically correlated to the driving oscillations of said tuning fork.
- a clock drive according to claim 10 wherein said areas comprise piezoelectric layers of alternating polarization.
- v g 13 A clock drive according to claiml, including an alternating current generator including a coilswitched electrically in series'with said oscillator, and electrical signalling means carried by said wheel and cooperatively related to said coil in the rotation of the wheel. 5 14. A.
- said wheel has a resiliently yieldable plastic perimeter
- said transmission comprises a pawl attached to said tuning fork and having a driving tip which bites into the wheelperimeter for driving the wheel rotatably in each driving oscillatorymovement and slides over the wheel piezoelectric tuning fork which transfers oscillationena narrow-band, frequency-determined time standard oscillator tuned to the basic oscillation frequency v of said tuning fork; and means operatively coupling said oscillator with the tuning fork;
- said oscillator comprising a second, smaller tuning fork made of metal and carrying piezoelectric transducers and additional weights at its free oscillating. ends. 17.
- a frequency-stabilized clock drive including a piezoelectric tuning fork which transfers oscillation en ergy by means of a transmission mechanism to a drive wheel and is connected in an oscillator circuit including coupled in the electrical circuit with said battery.
- a frequency-stabilized clock drive including a piezoelectric tuning fork which transfers oscillation en-. ergy by means of a transmission mechanism to a drive wheel and is connected in an oscillator circuit including an electrical energy supplying battery, the improvement comprising:
- a narrow-band, frequency-determined time standard oscillator tuned to the basic oscillation frequency of said tuning fork; 1 means operatively coupling said oscillator with the tuning fork; one prong of said tuning fork being connected to said transmission; a said oscillator comprising a smaller tuning fork; a second prong of said driving tuningfork being electrically coupled with one prong of said smaller tuning fork; an alternating current generator including said wheel and a coil; and 1 i said coil being connected at one end in said electrical circuit with said battery and at its opposite end connected with the remaining prong of said smaller tuning fork.
- a frequency-stabilized clock drive including a piezoelectric tuning fork which transfers oscillation energy by means of a transmission mechanism to a drive wheel and is connected in an oscillator circuit including an electrical energy supplying battery, the improvement comprising:
- an alternating current generator comprising said wheel and a coil
- a frequency-stabilized clock drive including a piezoelectric tuning fork which transfers oscillation energy by means of a transmission mechanism to a drive wheel and is connected in an oscillator circuit including an electrical energy supplying battery, the improvement comprising:
- an alternating current generator including a coil switched electrically in series with said oscillator
- electrical signalling means carried by said wheel and cooperatively related to said coil in the rotation of the wheel.
- a frequency-stabilized clock drive including a piezoelectric tuning fork which transfers oscillation energy by means of a transmission mechanism to a drive wheel and is connected in an oscillator circuit including an electrical energy supplying battery, the improvement comprising:
- said wheel having a resiliently yieldable plastic perimeter
- said transmission comprising a pawl attached to said tuning fork and having a driving tip which bites into the wheel perimeter for driving the wheel rotatably in each driving oscillatory movement and slides over the wheel perimeter during retraction oscillatory movement.
- a frequency-stabilized clock drive including a piezoelectric tuning fork which transfers oscillation energy by means of a mechanical transmission mechanism to a drive wheel and is connected in an oscillator circuit including an electrical energy supplying battery, the improvement comprising:
- said wheel having a resiliently yieldable plastic perimeter
- said transmission comprising a pawl attached to said tuning fork and having a driving tip which bites into the wheel perimeter for driving the wheel rotatably in each driving oscillatory movement and slides over the wheel perimeter during retraction oscillatory movement.
- a clock drive according to claim 22, wherein said oscillator circuit includes an oscillator operatively coupled with said tuning fork, electric signal producing area's regularly spaced circumferentially on said wheel by means of which the speed of rotation of the wheel can be measured, and a device stimulated by said areas in the rotation of the wheel to generate an electrical signal transmitted to said oscillator whereby the amplitude of the tuning fork and the speed of the drive wheel are maintained constant.
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- General Electrical Machinery Utilizing Piezoelectricity, Electrostriction Or Magnetostriction (AREA)
- Electromechanical Clocks (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19702035587 DE2035587A1 (de) | 1970-07-17 | 1970-07-17 | Uhrenantneb mit piezoelektrischer Stimmgabel |
Publications (1)
Publication Number | Publication Date |
---|---|
US3747326A true US3747326A (en) | 1973-07-24 |
Family
ID=5777110
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US00162227A Expired - Lifetime US3747326A (en) | 1970-07-17 | 1971-07-13 | Clock drive with piezoelectric tuning fork |
Country Status (8)
Country | Link |
---|---|
US (1) | US3747326A (de) |
AT (1) | AT315082B (de) |
CH (1) | CH987271A4 (de) |
DE (1) | DE2035587A1 (de) |
FR (1) | FR2099428A5 (de) |
GB (1) | GB1353176A (de) |
IT (1) | IT997021B (de) |
NL (1) | NL7109410A (de) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN113572387A (zh) * | 2021-07-27 | 2021-10-29 | 杭州电子科技大学 | 一种音叉型结构的压电致动器及其工作方法 |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
SU1278994A1 (ru) * | 1974-07-05 | 1986-12-23 | Киевский Ордена Ленина Политехнический Институт Им.50-Летия Великой Октябрьской Социалистической Революции | Пьезоэлектрический двигатель |
Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1849271A (en) * | 1929-01-25 | 1932-03-15 | Ward E Bower | Oscillation generator |
US2015410A (en) * | 1934-02-05 | 1935-09-24 | Continental Oil Co | Vibrating system |
GB993140A (en) * | 1961-02-16 | 1965-05-26 | Suwa Seikosha Kk | Improvements in or relating to electric timepieces |
US3207965A (en) * | 1962-08-11 | 1965-09-21 | Lavet Marius Jean | Adjustable mechanical oscillator for time-measuring apparatus |
FR1539922A (fr) * | 1967-08-09 | 1968-09-20 | Lip Sa | Appareil horaire portatif |
DE1523958A1 (de) * | 1965-08-28 | 1969-07-31 | Kienzle Uhrenfabriken Gmbh | Uhr mit Torsions- oder Biegeschwinger |
DE1809223A1 (de) * | 1968-11-15 | 1970-06-04 | Junghans Gmbh Geb | Armbanduhr mit einem piezoelektrischen Kristall als zeithaltendem Schwinger |
US3579974A (en) * | 1967-04-08 | 1971-05-25 | Gehap Gmbh & Co Kg | Electronically-controlled drive mechanism particularly for clocks |
US3636469A (en) * | 1969-11-10 | 1972-01-18 | Bunker Ramo | Beat frequency time standard |
-
1970
- 1970-07-17 DE DE19702035587 patent/DE2035587A1/de active Pending
-
1971
- 1971-06-30 AT AT565871A patent/AT315082B/de active
- 1971-07-05 CH CH987271D patent/CH987271A4/de unknown
- 1971-07-07 NL NL7109410A patent/NL7109410A/xx unknown
- 1971-07-13 US US00162227A patent/US3747326A/en not_active Expired - Lifetime
- 1971-07-14 IT IT7318/71A patent/IT997021B/it active
- 1971-07-15 GB GB3326071A patent/GB1353176A/en not_active Expired
- 1971-07-16 FR FR7126074A patent/FR2099428A5/fr not_active Expired
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1849271A (en) * | 1929-01-25 | 1932-03-15 | Ward E Bower | Oscillation generator |
US2015410A (en) * | 1934-02-05 | 1935-09-24 | Continental Oil Co | Vibrating system |
GB993140A (en) * | 1961-02-16 | 1965-05-26 | Suwa Seikosha Kk | Improvements in or relating to electric timepieces |
US3207965A (en) * | 1962-08-11 | 1965-09-21 | Lavet Marius Jean | Adjustable mechanical oscillator for time-measuring apparatus |
DE1523958A1 (de) * | 1965-08-28 | 1969-07-31 | Kienzle Uhrenfabriken Gmbh | Uhr mit Torsions- oder Biegeschwinger |
US3579974A (en) * | 1967-04-08 | 1971-05-25 | Gehap Gmbh & Co Kg | Electronically-controlled drive mechanism particularly for clocks |
FR1539922A (fr) * | 1967-08-09 | 1968-09-20 | Lip Sa | Appareil horaire portatif |
DE1809223A1 (de) * | 1968-11-15 | 1970-06-04 | Junghans Gmbh Geb | Armbanduhr mit einem piezoelektrischen Kristall als zeithaltendem Schwinger |
US3636469A (en) * | 1969-11-10 | 1972-01-18 | Bunker Ramo | Beat frequency time standard |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN113572387A (zh) * | 2021-07-27 | 2021-10-29 | 杭州电子科技大学 | 一种音叉型结构的压电致动器及其工作方法 |
Also Published As
Publication number | Publication date |
---|---|
GB1353176A (en) | 1974-05-15 |
CH987271A4 (de) | 1974-06-28 |
NL7109410A (de) | 1972-01-19 |
DE2035587A1 (de) | 1972-01-20 |
FR2099428A5 (de) | 1972-03-17 |
AT315082B (de) | 1974-05-10 |
IT997021B (it) | 1975-12-30 |
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