US2161980A - Elastically oscillating oscillator - Google Patents

Elastically oscillating oscillator Download PDF

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Publication number
US2161980A
US2161980A US693078A US69307833A US2161980A US 2161980 A US2161980 A US 2161980A US 693078 A US693078 A US 693078A US 69307833 A US69307833 A US 69307833A US 2161980 A US2161980 A US 2161980A
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Prior art keywords
oscillator
support
quartz
elastically
oscillating
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Expired - Lifetime
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US693078A
Inventor
Runge Wilhelm
Roosenstein Hans Otto
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Telefunken AG
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Telefunken AG
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    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
    • H03H9/02—Details
    • H03H9/05—Holders; Supports
    • H03H9/09—Elastic or damping supports
    • G—PHYSICS
    • G04—HOROLOGY
    • G04F—TIME-INTERVAL MEASURING
    • G04F5/00—Apparatus for producing preselected time intervals for use as timing standards
    • G04F5/04—Apparatus for producing preselected time intervals for use as timing standards using oscillators with electromechanical resonators producing electric oscillations or timing pulses
    • G04F5/06—Apparatus for producing preselected time intervals for use as timing standards using oscillators with electromechanical resonators producing electric oscillations or timing pulses using piezoelectric resonators
    • G04F5/063—Constructional details
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
    • H03H9/02—Details
    • H03H9/05—Holders; Supports
    • H03H9/0504—Holders; Supports for bulk acoustic wave devices
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S116/00—Signals and indicators
    • Y10S116/18—Wave generators
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/42—Piezoelectric device making

Definitions

  • This invention relates to elastically oscillating oscillators, or resonators with small damping action.
  • these energy losses are limited to a minimum value in an arrangement in which the oscillator or resonator is fixedly connected with its support while the shape of the support is such that in comparison with the oscillator it can be considered to be of soft springiness. Due to the rigid connection between oscillator and its support the losses which are produced by the impacts between these two parts, are eliminated while at the place of transition between oscillator and support due to the suddenly changing elastic wave resistance which occurs at this place, a nearly total reflection of the oscillations occurs preventing the elastic oscillations to be transferred at considerable extent from the oscillator to the support.
  • the springy mounting of the support is chosen in order to suppress undesirable side phenomena, for instance oscillations of a different kind than the desired one.
  • Fig. 1 shows the construction of an oscillating quartz plate as often used in the high-frequency field, as modified in accordance with the inven- 5 tion.
  • the actual quartz oscillator O is conceived as an annular disk, while the support forms a thin annular disk U rigidly connected to the quartz by means of suitable binding material.
  • the material is reduced to a great extent in order to render the reflection of the oscillation more favorable at this place.
  • it must be endeavored to make the dimensions of the reduced place small in comparison with the wave length of the elastic oscillation in the material of the oscillator.
  • a particularly simple embodiment is obtained when the oscillator together with its support is cut by means of an angular-shaped grinding stone from a block of the same material. Due to the entire elimination of energy losses in the connecting material between oscillator and support a further damping reduction is thereby obtained. The damping is furthermore reduced if as shown in Fig. 1 the support of the oscillator is laid in a point which coincides as much as possible with the oscillation nodes (neutral zone) of the elastic oscillations.
  • Fig. 2 An arrangement accomplishing this is shown in Fig. 2.
  • the actual quartz oscillator O is conceived as an annular disk which together with its supports R1, R2, Z1, Z2, Z3 is cut by means of an angular-shaped grinding stone from a quartz block of the same material in any useful direction of the electrical axis.
  • the support is formed of one or several concentric rings R1, R2 etc. separated by means of thin intermediate rings Z1, Z2 etc. It must be thought of as a mechanical equivalent of an electrical filter chain consisting of capacities and inductances.
  • the electrodes E1 and E2 exciting the oscillator are suitably placed at a short distance from the quartz plate.
  • the functioning of this suspension is such that the slight movement transmitted from oscillator O to the intermediate ring Z1 is nearly entirely reflected back to the oscillator O at the place of transition of Z1 and R1. To the extent to which this action does not take place an utmost small movement of ring
  • the frequency determining formula is represented by the well-known quartz crystal equations, and owing to the improved support of this invention the frequency can be determined more accurately than when crystals are supported by other methods known in the prior art.
  • the oscillator is .used in a rarefied space.
  • Elastically oscillating oscillator having a small damping action comprising an oscillator cut from a block of material in such a manner that said block provides the support for said oscillator.
  • Elastically' oscillating oscillator having a small damping action comprising a central piezoelectric oscillator cut from a block of material in such a manner that said block provides the support for said oscillator.
  • a piezo-electric resonator comprising a vibrating. portion and a flexible member integral with. sai'd' portion. said flexible member serving to mountthe resonator on a support.
  • a crystal resonator comprising a vibrating portion,- a connecting element and a base portion.
  • a crystal resonator comprising a vibrating portion, a. connecting element, and a base portion, the connecting element being of less thickness 8.
  • a crystal resonator comprising a vibrating portion, a connecting element and a base portion all I formed. from a single crystal.

Description

June 13, 1939.
w. RUNGE ET AL ELASTICALLY OSCILLATLNG OSCILLATOR Filed Oct. 11, 1935 Egg- 1 INVENTORS WILHELM RUNGE HANS 0T OSENSTEIN BY I) ATTORNEY Patented June 13, 1939 UNITED STATES PATENT OFFICE ELASTIOALLY OSCILLATING OSCILLATOR Application October 11, 1933,Serial No. 693,078 In Germany October 12, 1932 9 Claims.
This invention relates to elastically oscillating oscillators, or resonators with small damping action.
It has been found in the practical operation with elastically oscillating oscillators and resonators that they lose a considerable amount of energy mostly about their supporting points which dissipates into the surrounding space. Since in general an undesirable increase in damping is thereby produced, the supporting points of such systems are placed in the known manner into the oscillation nodes of the desired frequency. As an example may be mentioned the tuning fork which is supported at the point of junction of the two tines. That also here a considerable amount of energy can be withdrawn over the support can be noted from the sound radiation which occurs when the fork is set with its handle upon a suitable resonant board.
In oscillators and resonators with extremely low damping action, in particular in piezo-electric or magneto-striction oscillators as used in the high-frequency field, this method of support meets with mechanical difflculties since it is a diflicult matter to arrange the point of support so as to coincide with sufficient accuracy with the oscillation nodes. Furthermore, in most of the cases the nodal movement is not equal to zero although it is a minimum. If the oscillator is supported at these places for instance clamped or carried upon knife edges, such bearing easily causes a considerable increase in damping.
In accordance with the invention these energy losses are limited to a minimum value in an arrangement in which the oscillator or resonator is fixedly connected with its support while the shape of the support is such that in comparison with the oscillator it can be considered to be of soft springiness. Due to the rigid connection between oscillator and its support the losses which are produced by the impacts between these two parts, are eliminated while at the place of transition between oscillator and support due to the suddenly changing elastic wave resistance which occurs at this place, a nearly total reflection of the oscillations occurs preventing the elastic oscillations to be transferred at considerable extent from the oscillator to the support. The springy mounting of the support is chosen in order to suppress undesirable side phenomena, for instance oscillations of a different kind than the desired one. The principles underlying the present invention will be more readily understood by reference to the following description, which is accompanied by a drawing wherein Figs. 1 and 2 show two embodiments of the invention.
Fig. 1 shows the construction of an oscillating quartz plate as often used in the high-frequency field, as modified in accordance with the inven- 5 tion. In this case the actual quartz oscillator O is conceived as an annular disk, while the support forms a thin annular disk U rigidly connected to the quartz by means of suitable binding material. At the place of transition U between the quartz and support, the material is reduced to a great extent in order to render the reflection of the oscillation more favorable at this place. At any case it must be endeavored to make the dimensions of the reduced place small in comparison with the wave length of the elastic oscillation in the material of the oscillator.
A particularly simple embodiment is obtained when the oscillator together with its support is cut by means of an angular-shaped grinding stone from a block of the same material. Due to the entire elimination of energy losses in the connecting material between oscillator and support a further damping reduction is thereby obtained. The damping is furthermore reduced if as shown in Fig. 1 the support of the oscillator is laid in a point which coincides as much as possible with the oscillation nodes (neutral zone) of the elastic oscillations.
Finally it is also possible by a second application of the inventive idea to cause the remaining energy which would be dissipated across the support into the surrounding space to be again reflected towards the quartz oscillator. An arrangement accomplishing this is shown in Fig. 2. In this arrangement the actual quartz oscillator O is conceived as an annular disk which together with its supports R1, R2, Z1, Z2, Z3 is cut by means of an angular-shaped grinding stone from a quartz block of the same material in any useful direction of the electrical axis. In this case the support is formed of one or several concentric rings R1, R2 etc. separated by means of thin intermediate rings Z1, Z2 etc. It must be thought of as a mechanical equivalent of an electrical filter chain consisting of capacities and inductances. The electrodes E1 and E2 exciting the oscillator are suitably placed at a short distance from the quartz plate. The functioning of this suspension is such that the slight movement transmitted from oscillator O to the intermediate ring Z1 is nearly entirely reflected back to the oscillator O at the place of transition of Z1 and R1. To the extent to which this action does not take place an utmost small movement of ring The frequency determining formula is represented by the well-known quartz crystal equations, and owing to the improved support of this invention the frequency can be determined more accurately than when crystals are supported by other methods known in the prior art.
The still remaining damping of such oscillator is caused to a considerable portion'by the friction of the gas surrounding the oscillator. Therefore,
it will be advantageous if the oscillator is .used in a rarefied space.
We claim:
1. Elastically oscillating oscillator having a small damping action comprising an oscillator cut from a block of material in such a manner that said block provides the support for said oscillator.
2. Elastically' oscillating oscillator having a small damping action comprising a central piezoelectric oscillator cut from a block of material in such a manner that said block provides the support for said oscillator.
-. than the vibrating portion.
3. Elastically oscillating oscillator having a small damping action comprising a central disklike piezo-electric oscillator having a plurality of concentric rings cut from a block of material in such a manner that said concentric rings pros s El y q for id 9$F=il t -142'fiilasticallytoscillating oscillator having a small damping action comprising a 'piezo-electric oscillator cut from a block of quartz material in such a manner that said quartz provides the support; for said oscillator.
5. A piezo-electric resonator comprising a vibrating. portion and a flexible member integral with. sai'd' portion. said flexible member serving to mountthe resonator on a support.
6. A crystal resonator comprising a vibrating portion,- a connecting element and a base portion. 7. A crystal resonator comprising a vibrating portion, a. connecting element, and a base portion, the connecting element being of less thickness 8.-.A-resonator comprising a vibrating portion, a connecting element and a base portion all I formed. from a single crystal.
:9. .A resonator comprising a vibrating portion, a connecting-element and-a base portion, all
WILHEIM RUNGE; HANS OTI'O ROOSENSTEIN.
DISCLAIMER 2,161,980.Wt'lhelm Range and Hans Otto Roosenste'in, Berlin, Germany. ELASTI- CALLY OSCILLATING OSCILLATOR. Patent dated June 13, 1939. Disclaimer filed May 24, 1940, by the inventors; the assignee, Telefunken Gesellschaft fur Drahtlose Telegraphic, m. b. H., consenting.
Hereby disclaim claims 1, 5, 8, and 9 of said patent, and disclaim from the scope of clalms 4, 6, and 7 all resonators except those wherein the vlbratmg or oscillating portion is centrally located with respect to the support or base portion.
[Ofiicial Gazette June 25, 1.940.]
DISCLAIMER 2,161 ,980.Wz'lhelm Runge and Hans Otto Roosenstein, Berlin, Germany. ELASTI- CALLY OSOILLATING OSCILLATOR. Patent dated June 13, 1939. Disclaimer filed May 24, 1940, by the inventors; the assignee, Telefunk'en Gesellschafl fur Drahtlose Telegraphic, m. b. H., consenting.
Hereby disclaim claims 1, 5, 8, and 9 of said patent, and disclaim from the scope of claims 4, 6, and 7 all resonators except those wherein the vibrating or oscillating portion is centrally located with respect to the support or base portion.
[Ofiicial Gazette June 25, 1 940.]
US693078A 1932-10-13 1933-10-11 Elastically oscillating oscillator Expired - Lifetime US2161980A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DET41490D DE664983C (en) 1932-10-13 1932-10-13 Oscillator or resonator designed as a piezoelectric crystal with low radiation damping
DE447665X 1934-12-10

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US51738A Expired - Lifetime US2077204A (en) 1932-10-13 1935-11-27 Piezoelectric oscillating crystal

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US51738A Expired - Lifetime US2077204A (en) 1932-10-13 1935-11-27 Piezoelectric oscillating crystal

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Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2543500A (en) * 1946-06-27 1951-02-27 Gen Motors Corp Means for suppressing transverse modes of oscillation in a piezoelectric crystal
US2774892A (en) * 1951-05-29 1956-12-18 Bendix Aviat Corp Annular vibrator with lumped loading
US2799789A (en) * 1949-04-06 1957-07-16 John M Wolfskill Piezoelectric crystal apparatus and method of making the same
US2802955A (en) * 1953-05-04 1957-08-13 Donald M Kitterman Piezoelectric unit
US2956184A (en) * 1954-11-01 1960-10-11 Honeywell Regulator Co Transducer
US3360664A (en) * 1964-10-30 1967-12-26 Gen Dynamics Corp Electromechanical apparatus
US3382841A (en) * 1964-09-14 1968-05-14 Gen Dynamics Corp Flexural disc transducer
US3516052A (en) * 1965-01-27 1970-06-02 Gen Dynamics Corp Acoustic apparatus
US3576453A (en) * 1969-05-02 1971-04-27 Bell Telephone Labor Inc Monolithic electric wave filters
US3617780A (en) * 1967-10-26 1971-11-02 Hewlett Packard Co Piezoelectric transducer and method for mounting same
US3906260A (en) * 1971-09-22 1975-09-16 Suwa Seikosha Kk Crystal vibrator
US4631437A (en) * 1985-01-10 1986-12-23 The United States Of America As Represented By The Secretary Of The Army Stress compensated piezoelectric crystal device
US4814662A (en) * 1985-06-14 1989-03-21 Etat Francais As Represented By The Delegue General Pour L'armement Piezoelectric resonator with either minimal or extreme sensitivity to external pressure stresses
US4972389A (en) * 1973-01-02 1990-11-20 The United States Of America As Represented By The Secretary Of The Navy Electroacoustic transducer
US5198716A (en) * 1991-12-09 1993-03-30 The United States Of America As Represented By The United States Department Of Energy Micro-machined resonator
US5339051A (en) * 1991-12-09 1994-08-16 Sandia Corporation Micro-machined resonator oscillator
US6016025A (en) * 1997-05-15 2000-01-18 M-Tron Industries, Inc. Selected overtone resonator with channels
US20030132811A1 (en) * 2000-07-17 2003-07-17 Yoshiaki Nagaura Piezoelectric device and acousto-electric transducer and method for manufacturing the same
US20040036380A1 (en) * 2002-06-25 2004-02-26 Seiji Oda Crystal unit

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE763208C (en) * 1938-07-10 1953-06-01 Heinz Evertz Holder for piezoelectric crystals
DE927748C (en) * 1944-02-20 1955-05-16 Lorenz C Ag Arrangement for holding a vibrating crystal
DE945702C (en) * 1944-09-17 1956-07-12 Lorenz C Ag Piezoelectric switching element
US2472179A (en) * 1947-06-11 1949-06-07 Tibbetts Lab Inc Piezoelectric device
US2482730A (en) * 1947-06-23 1949-09-20 Premier Crystal Lab Inc Piezoelectric crystal unit
US2657320A (en) * 1948-12-30 1953-10-27 Bell Telephone Labor Inc Piezoelectric crystal unit
US2700738A (en) * 1951-05-05 1955-01-25 Ibm Delay-line end cell
US2699508A (en) * 1951-12-21 1955-01-11 Selectronics Inc Method of mounting and construction of mounting for low frequency piezoelectric crystals
NL97839C (en) * 1953-06-15
DE1101032B (en) * 1954-04-27 1961-03-02 Dr Hans Karl Hach Ceramic electrostrictive transducer and process for its manufacture
US2856549A (en) * 1955-06-06 1958-10-14 Int Standard Electric Corp Method of mounting piezo-electric crystals
DE2703334A1 (en) * 1976-01-29 1977-08-04 Seiko Instr & Electronics PIEZOELECTRIC SWINGER
FR2445029A1 (en) * 1978-12-19 1980-07-18 France Etat PIEZOELECTRIC DRAWER RESONATOR
DE3724290A1 (en) * 1987-07-22 1989-02-02 Siemens Ag ELECTRODE FOR PIEZOELECTRIC COMPOSITES
DE4321949C2 (en) * 1992-07-03 1997-07-10 Murata Manufacturing Co Vibrator unit
JP3003429B2 (en) * 1992-10-08 2000-01-31 富士電機株式会社 Torsional vibrator and optical deflector

Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2543500A (en) * 1946-06-27 1951-02-27 Gen Motors Corp Means for suppressing transverse modes of oscillation in a piezoelectric crystal
US2799789A (en) * 1949-04-06 1957-07-16 John M Wolfskill Piezoelectric crystal apparatus and method of making the same
US2774892A (en) * 1951-05-29 1956-12-18 Bendix Aviat Corp Annular vibrator with lumped loading
US2802955A (en) * 1953-05-04 1957-08-13 Donald M Kitterman Piezoelectric unit
US2956184A (en) * 1954-11-01 1960-10-11 Honeywell Regulator Co Transducer
US3382841A (en) * 1964-09-14 1968-05-14 Gen Dynamics Corp Flexural disc transducer
US3360664A (en) * 1964-10-30 1967-12-26 Gen Dynamics Corp Electromechanical apparatus
US3516052A (en) * 1965-01-27 1970-06-02 Gen Dynamics Corp Acoustic apparatus
US3617780A (en) * 1967-10-26 1971-11-02 Hewlett Packard Co Piezoelectric transducer and method for mounting same
US3576453A (en) * 1969-05-02 1971-04-27 Bell Telephone Labor Inc Monolithic electric wave filters
US3906260A (en) * 1971-09-22 1975-09-16 Suwa Seikosha Kk Crystal vibrator
US4972389A (en) * 1973-01-02 1990-11-20 The United States Of America As Represented By The Secretary Of The Navy Electroacoustic transducer
US4631437A (en) * 1985-01-10 1986-12-23 The United States Of America As Represented By The Secretary Of The Army Stress compensated piezoelectric crystal device
US4814662A (en) * 1985-06-14 1989-03-21 Etat Francais As Represented By The Delegue General Pour L'armement Piezoelectric resonator with either minimal or extreme sensitivity to external pressure stresses
US5198716A (en) * 1991-12-09 1993-03-30 The United States Of America As Represented By The United States Department Of Energy Micro-machined resonator
US5339051A (en) * 1991-12-09 1994-08-16 Sandia Corporation Micro-machined resonator oscillator
US6016025A (en) * 1997-05-15 2000-01-18 M-Tron Industries, Inc. Selected overtone resonator with channels
US20030132811A1 (en) * 2000-07-17 2003-07-17 Yoshiaki Nagaura Piezoelectric device and acousto-electric transducer and method for manufacturing the same
US6952074B2 (en) * 2000-07-17 2005-10-04 Yoshiaki Nagaura Piezoelectric device and acousto-electric transducer and method for manufacturing the same
US20060016065A1 (en) * 2000-07-17 2006-01-26 Yoshiaki Nagaura Piezoelectric device and acousto-electric transducer and method for manufacturing the same
US20040036380A1 (en) * 2002-06-25 2004-02-26 Seiji Oda Crystal unit
US7012355B2 (en) * 2002-06-25 2006-03-14 Nihon Dempa Kogyo Co., Ltd. Crystal unit

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Publication number Publication date
GB447665A (en) 1936-05-22
US2077204A (en) 1937-04-13
DE664983C (en) 1938-10-01

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