[go: up one dir, main page]

US2692344A - Electromechanical transducing device - Google Patents

Electromechanical transducing device Download PDF

Info

Publication number
US2692344A
US2692344A US294844A US29484452A US2692344A US 2692344 A US2692344 A US 2692344A US 294844 A US294844 A US 294844A US 29484452 A US29484452 A US 29484452A US 2692344 A US2692344 A US 2692344A
Authority
US
United States
Prior art keywords
winding
vibrating
mechanical
members
electro
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
Application number
US294844A
Other languages
English (en)
Inventor
Burgt Cornelis Martinus Va Der
Klinkbamer Jacob Fredrik
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hartford National Bank and Trust Co
Original Assignee
Hartford National Bank and Trust Co
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Hartford National Bank and Trust Co filed Critical Hartford National Bank and Trust Co
Application granted granted Critical
Publication of US2692344A publication Critical patent/US2692344A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic elements; Electromechanical resonators
    • H03H9/46—Filters
    • H03H9/62—Filters comprising resonators of magnetostrictive material
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic elements; Electromechanical resonators
    • H03H9/02—Details
    • H03H9/125—Driving means, e.g. electrodes, coils
    • H03H9/135—Driving means, e.g. electrodes, coils for networks consisting of magnetostrictive materials
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic elements; Electromechanical resonators
    • H03H9/22—Constructional features of resonators consisting of magnetostrictive material

Definitions

  • This invention relates to electro-mechanical transducing devices, more particularly, to electro-mechanical transducing devices which make use of a member having magneto-strictive properties'.
  • electro-mechanical transducing devices comprised a vibrating member in expansi'onal-vibration, i. e., the diameter of the member varied in accordance with a magnetic alternating field surrounding the member.
  • these devices have had the disadvantages that the resonant peak of the Vibrations was very broad and, furthermore, that the entire member wasvibrating so that it was exceedingly dfiCllt to support ⁇ the Vibrating member without materially dampening or otherwise interfering with the vibrations unless extremely critical flexible supports were utilized.
  • an electro-mechanical transducing device comprises a vibrating member in torsional-vibration, i. e., the upper surface of the member exhibits a periodically changing twist relative to its bottom surface.
  • the electro-mechanical transducing device comprises a magneto-strictive, substantialy radially symmetrical,
  • annular member consisting of a highly' magnetically permeable, substantially electrically non-conductive material placed in a uni-drectonal polarizing field.
  • the annular member is provided with a winding about a portion thereof so that when an alternating current passes through the Winding the member is set into torsional-vibration.
  • FIG. 1 is a View, in cross-section of one form 2 of an electro-mechanical vibrating. device in accordance with the invention
  • Fig. 2 is a curve of the impedance characteristic of the device shown in Fig. 1;
  • Figs. 3 and 4 are a cross-sectional and plan view, respectively, of another form of electromechanical vibrating device according to the in vention;
  • Figs. 5 and 6 are ⁇ a cross-sectional and plan View, respectively, of sti-ll another form of electro-mechanical vibratng device according to the invention.
  • Fig'. a is a cross -secti'onal View of a further modification
  • Fig. 7 is a schematic view of one form of circui t arrangement ior compensating for the initial impedance Zo of the device shown intFig. 1,;
  • Figs. 8 and 9 are a cross-sectional and plan View, respectively, of two mechanically coupled vibrating devices
  • Fig. IO- is a curve of the impedance characteristic of the device shown in Figs. ⁇ 8 and 9.
  • Figs. 11 and 12 show two embodiments, wherein permanent magnets of non-conductive material rest against the vibrator member.
  • An electro-mechanical' transducng device as shown in Fig. 1 comprises a vibrator member I arranged in a p'olarizing magnetic field Ha pro **d by a pair of disc-shaped permanent magnetic members 3 and 4 having a direction of magnetization N-S substantially parallel with a central axis 5' of the member I.
  • the magneto-strictive member I is set in torsional vi'bration, i. e., the upper surface of the member l exhibits a periodically changing twist relatively to its bottom surface.
  • the curve a in Fig. 2' indicates the impedance measured between the ends of the winding 2: for different frequencies of alternating current suppliedthereto.
  • a considerable impedance Zm Will be measured between the ends of the ⁇ winding 2, and at frequencies below' and above this resonant frequency, this impedance acquires substantially a constant value Zu which depends upon the Volume and the permeability of the member l.
  • the impedance curve may be regarded as the sum of a constant impedance Zo and an impedance according to the curve C shown in dash lines in Fig. 2, which curve C corresponds to the impedance of a tuned circuit.
  • the permanent field Ho produced by the flat annular permanent magnets 3 and 4 will, if these permanent magnets are supported by non-magnetic supports, be comparatively weak due to the large reluctance of such supports.
  • the supporting members ll, !2, l3 for the permanent magnets 3 and 4 preferably consist of ferromagnetic material.
  • FIGs. 3 and 4 show a modification of the device shown in Fig. l, in which a more compact construction and a stronger polarizing field Ho is obtained.
  • FIG. 4 is a plan View of the device shown in Fig. 3 with the top disc removed.
  • a permanent magnet l 5 of annular shape is arranged about an annular vibrating member IS so that the polarizing field for the member 16 is produced betwen two rngor discshaped ferromagnetic bodies ll and IB.
  • a coil form 29 about which is wound a winding 2l is arranged about the member [6 at an interruption of the permanent magnet
  • Figs. 5 and 6 show a further modification of the device shown in Fig. 1.
  • a discshaped permanent magnet 23 is arranged within an annular vibrating member 24, the combination being sandwiched between a pair of ferromagnetic plates 25 and 26, thereby producing a sufficient permanent magnetic field Ho at the member 24.
  • a cylindrical support 21 contains bolts 28, 29 and 33 for supporting the vibrating member 24, which supports preferably consist of non-magnetic material.
  • the support 27 may carry a ferromagnetic shunt 21', as shown in Fig. Ga, by means of which the strength of the field Ho can be adjusted between plates 25 and 26.
  • a coil form 31 about which is wound a winding 32 is ftted in interruptions of the permanent magnet 23, of the ferromagnetic discs 25 and 26 and of the support 21.
  • the impedance Zo increases. Therefore, it is also advantageous, according to Fig. 11, to place two permanent magnets 63 and 64 of substantially non-conduetive material against the vibrator member 6l.
  • the winding 62 may then be simply arranged about the assembly of the vibrator member Bl and the nonconductive permanent magnets 63 and 64 without incurring additional Foucault current losses.
  • Fig. 7 shows diagrammatically how the initial impedance zo shown in Fig. 2 can be compensated for in the device shown in Fig. 1.
  • two windings 2, 2' are arranged around the vibrating member l and are connected to a primary 38 and a secondary 39 winding, respectively, of a transformer 40 having a given transformation ratio.
  • the connections are arranged so that the input current traversing the winding 2, traverses the primary 38 of transformer l5 in the opposite direction to that of the output current traversing the winding 2' and the secondary 39 of transformer 40.
  • the number of turns of the windings 38 and 39 are suitably chosen to produce a voltage across the secondary winding 39 in relation to the input current through windings 2 and 38 corresponding to the said impedance Zo to be compensated.
  • the voltages across windings 2' and 39 compensate each other involving a transfer characteristic of the device corresponding to curve c of Fig. 2.
  • Figs. 8 and 9 show a device comprising two vibrating members 50 and 5l supported at points of their respective nodal planes, an input winding 52 being arranged around the vibrating member 50 and an output winding 53 surrounding the vibrating member El, while both vibrating members 50 and 5! are mechanically intercoupled by non-magnetic, for example, aluminium, coupling elements 54, 55, 56 which transmit the vbrations of the vibrating member 50 to the vibrating member 5l.
  • non-magnetic for example, aluminium
  • coupling elements 54, 55, 56 which transmit the vbrations of the vibrating member 50 to the vibrating member 5l.
  • the band-width chiefiy depending upon the size of the contact surfaces that is to say, the smaller the area of the contact surfaces, the looser the coupling, and the narrower the bandwidth.
  • a point or knife blade contact will have practically zero coupling, and the characteristic of Fig. 10 will be practically reduced to a straight line.
  • the windings 52 and 53 are shown in the same plane. However, they may be provided in different planes in order that the height of the coupling elements 54, 55, 56 may be as small as possible.
  • a pair of dsc-shaped permanent magnets 59, se enclose the vibrating members 50 and l.
  • the vibrating members 50, 5I may be supported by bolts at points along their nodal planes, respectively, or by pieces of paper, as described above in connection with the embodiment illustrated in Fig. 1.
  • Fig. 12 shows a similar device as shown in Fig. 11, comprising two vibrator members 'H and 'I I whose mechanical resonance frequencies may be slightly diiTerent from one another, so that the impedance measured between the ends of winding 12 in the frequency range between these two resonance frequencies varies only slightly with the frequency, in other words it has a band-pass filter characteristic.
  • the winding 12 is loosely arranged on the permanent magnets 13, '13' and 'M projecting from the vibrator members 'H and 'H so that it does not damp the mechanical Vibration. If a sufficiently strong polarizing field is available, the magnet 13' may, if desired, be omitted.
  • disc-shaped vibrating members are used.
  • the invention also applies to devices comprising tubular or other hollow vibrating members having rotational symmetry by giving them different heights and/ or diameters.
  • a suitable material for the vibrating members of the various embodiments shown in the drawing is nickel-Zinc ferrite of the high-permeable, substantially non-conductive type having a composition of approximately 18 mol per cent of Ni O, 32 mol per cent of ZnO and 50 mol per cent of Fe2O3.
  • This and other types of materials such as those described in U. S. Patents Nos. 2,452,529; 2,452,530; 2,452,531; 2,551,711; 2,579,- 978, are suitable for and may be used for the purpose of this invention.
  • a suitable material for the permanent magnets particularly in the examples shown in Figs. 3, 5, 11 and 12 reference is made to the materials described in a U. S. patent application filed July '7, 1951, Serial No. 239364. These materials are characterised by a composition of substantially non-cubic' crystals of polyoxides of iron and at least one of the metals barium, strontium, lead and, if desired, calcium.
  • An electro-mechanical vibrating device comprising a magneto-strictive hollow member consisting of a highly megnetically permeable substantially electrically non-conductive material and being substantially radially symmetrical about a given axis of rotation extending through the center thereof, means to produce a uni-directioral polarizing field in a direction substantially parallel to said axis of rotation, and a winding wound about a portion of said hollow member and surrounding an axial section thereof so that when alternating current is passed through said winding said member is torsionally vibrated.
  • An electro-mechanical vibrating device comprising a magneto-strictive hollow annular member consisting of a highly magnetically permeable substantially electrically non-conductive material and being substantially radially symmetrical about a given axis of rotation extending through the center thereof, means to produce a oni-directional polarizing field in a direction substantially parallel to said axis of rotation, a winding wound about a portion of said annular member and surrounding an axial section thereof so that when an alternating current is passed through said winding said member is torsionally vibrated about its nodal plane, and means for supporting said member along its nodal plane.
  • An electro-mechanical vibrating device comprising a magneto-strictive hollow annular member consisting of a highly magnetically permeable substantially electrically non-conductive material and being substantially radially symmetrical about a given axis of rotation extending through the center thereof, means including a permanent magnet to produce a uni-directional polarizing field in a direction substantially parallel to said axis of rotation, a winding wound about a sector of said annular member so that when an alternating current is passed through said winding said member is torsionally vibrated about its nodal plane, and means for supporting said member at three points along its nodal plane.
  • An' electro-mechanical vibrating device comprising a magneto-strictive hollow annular member consisting of a highly magnetically permeable substantially electrically non-conductive material and being substantially radially symmetrical about a given axis of rotation extending through the center thereof, an annular permanent magnet magnetized in the direction of said axis surrounding said member, a pair of annular ferromagnetic disc-shaped bodies disposed on opposite sides of said member and providing with said magnet a uni-directional polarizing field in a direction substantially parallel to said axis of rotation, and a winding wound about a sector of said annular member so that when an alternating current is passed through said winding said member is torsionally vibrated.
  • An electro-mechanical vibrating device comprising a magneto-strictive hollow annular member consisting of a highly magnetically permeable substantially electrically non-conductive material and being substantially radially symmetrical about a given axis of rotation extending through the center thereof, a cylindrically shaped permanent magnet disposed within said hollow member, a pair of ferromagnetic disc-shaped bodies disposed on opposite sides of said member and providing with said magnet a uni-directional polarizing field in a direction substantially parallel to said axis of rotation, and a winding wound about a sector of said annular member so that when an alternating current is passed through said winding said member is torsionally vibrated.
  • An electro-mechanical vibrating device comprising a magneto-strictive hollow annular member consisting of a highly magnetically permeable substantially electrically non-conductive material and being substantially radially symmetrical about a given axis of rotation extending through the center thereof, means to produce a unidirectional polarizing field in a direction substantially parallel to said axis of rotation, a winding wound about a sector of said annular passed through said winding said member is torsionally vibrated, and means for compensating for the impedance measured between the ends of said winding at frequencies different from the resonant f'equency thereof.
  • An electro-mechanical vibrating device comprising a pair of spaced magneto-strictive hollow annular members each consisting of a highly nagnetically permeable substantially electrically non-conductive material, said members being substantally radiaily symmetrical about a common axis of rotation extending through the Centers thereof, a plurality of non-magnetic coupiing elements each affixed to each of said members, means to produce a uni-directional polarizing field in a direction substantially parallel to said axis of rotation, an output winding wound about a sector of one of said members, and an input winding wound about a sector of the other of said members so that when an alternating current is passed through said input winding said members are torsionally vibrated.
  • An electro-mechanical vibrating device comprising a magneto-strictive substantially radially symmetrical hollow annular member consisting of a highly magnetically permeable substantially electrically non-conductive material and having a given axis of rotation extending through the center thereof, two annular permanent magnets of substantially non conductive material provided at both sides of and against said annular member to produce a uni-directional polarizing field in a direction substantially parallel to said axis of rotation, and a winding Wound about a portion of said annular member and surrounding an axial section of the assembly of said annular member and said permanent magnets so that when an alternating current is passed through said winding said member is torsionally vibrated.
  • a device as claimed in claim 8 in which the impedance, measured between the ends of the winding, exhibits a band-pass filter characteristic, characterzed in that a plurality of ringshaped vibrator members having different mechanical resonance frequencies are provided between a plurality of ring-shaped permanent magnets, the winding surrounding the assembly of an axial section of vibrator members and magnets.

Landscapes

  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • General Electrical Machinery Utilizing Piezoelectricity, Electrostriction Or Magnetostriction (AREA)
  • Oscillators With Electromechanical Resonators (AREA)
  • Apparatuses For Generation Of Mechanical Vibrations (AREA)
  • Piezo-Electric Or Mechanical Vibrators, Or Delay Or Filter Circuits (AREA)
US294844A 1951-07-02 1952-06-21 Electromechanical transducing device Expired - Lifetime US2692344A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
NL313249X 1951-07-02

Publications (1)

Publication Number Publication Date
US2692344A true US2692344A (en) 1954-10-19

Family

ID=19783704

Family Applications (1)

Application Number Title Priority Date Filing Date
US294844A Expired - Lifetime US2692344A (en) 1951-07-02 1952-06-21 Electromechanical transducing device

Country Status (7)

Country Link
US (1) US2692344A (fi)
BE (2) BE512514A (fi)
CH (1) CH313249A (fi)
DE (2) DE969549C (fi)
FR (2) FR1068674A (fi)
GB (1) GB714118A (fi)
NL (5) NL77918C (fi)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2770782A (en) * 1952-08-30 1956-11-13 Rca Corp Frequency selective coupling system
US2876419A (en) * 1954-12-01 1959-03-03 Bell Telephone Labor Inc Magnetostriction devices
US2895113A (en) * 1954-06-23 1959-07-14 Marconi Wireless Telegraph Co Magneto-strictive resonators
US3020426A (en) * 1956-02-14 1962-02-06 Philips Corp Ferromagnetic material
US3283184A (en) * 1963-11-04 1966-11-01 Phillips Petroleum Co Detonation pickup

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL225484A (fi) * 1957-03-22
DE1616692B1 (de) * 1962-03-22 1970-03-05 Telefunken Patent Als Laufzeitkette verwendbare frequenzselektive Anordnung nach Art eines elektromagnetischen Filters
DE1279863B (de) * 1962-07-28 1968-10-10 Ibm Deutschland Elektroakustischer Wandler fuer eine Torsionsschwingungen uebertragende Verzoegerungsleitung

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2249835A (en) * 1937-11-11 1941-07-22 Bell Telephone Labor Inc Magnetostrictive vibrator
US2452531A (en) * 1943-05-31 1948-10-26 Hartford Nat Bank & Trust Co Process of manufacturing a magnetic material and magnetic core

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB576275A (en) * 1944-01-10 1946-03-27 High Duty Alloys Ltd Improvements in apparatus for exciting or detecting torsional oscillations in elastic bodies
US2521136A (en) * 1949-04-28 1950-09-05 Commerce National Bank Of Hydrophone

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2249835A (en) * 1937-11-11 1941-07-22 Bell Telephone Labor Inc Magnetostrictive vibrator
US2452531A (en) * 1943-05-31 1948-10-26 Hartford Nat Bank & Trust Co Process of manufacturing a magnetic material and magnetic core

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2770782A (en) * 1952-08-30 1956-11-13 Rca Corp Frequency selective coupling system
US2895113A (en) * 1954-06-23 1959-07-14 Marconi Wireless Telegraph Co Magneto-strictive resonators
US2876419A (en) * 1954-12-01 1959-03-03 Bell Telephone Labor Inc Magnetostriction devices
US3020426A (en) * 1956-02-14 1962-02-06 Philips Corp Ferromagnetic material
US3283184A (en) * 1963-11-04 1966-11-01 Phillips Petroleum Co Detonation pickup

Also Published As

Publication number Publication date
NL170958B (nl)
BE521272A (fi)
GB714118A (en) 1954-08-25
DE970150C (de) 1958-08-21
NL162356B (nl)
FR1068674A (fr) 1954-06-30
CH313249A (de) 1956-03-31
FR64457E (fr) 1955-11-10
DE969549C (de) 1958-06-19
NL162357B (nl)
BE512514A (fi)
NL77918C (fi)
NL83690C (fi)

Similar Documents

Publication Publication Date Title
US2501488A (en) Magnetostrictively driven mechanical wave filter
US2834943A (en) Mechanically coupled electromechanical and magnetomechanical transducers
US2249835A (en) Magnetostrictive vibrator
US2503155A (en) Variable inductance device
US2692344A (en) Electromechanical transducing device
US2636135A (en) Stress-coupled core and crystal transformer
US2592721A (en) Filter using magnetostrictive rings
US2994016A (en) Magnetic translating device
US2736824A (en) Magnetostrictive ferrites
US2167078A (en) Electromechanical system
US2915637A (en) Tuning system for toroid inductors
US2740941A (en) Variable reactors
US3044028A (en) Magnetic circuit element transducer
US2755468A (en) Antenna combined with magnetic coupling core
US2059393A (en) Magnetic core for high frequency inductances
Hathaway et al. Survey of mechanical filters and their applications
US2652543A (en) Electromechanical filter
US2463778A (en) Magnetic shielding
US2607814A (en) Magnetostrictive four-pole
US1982690A (en) Selective radio circuit
US2305626A (en) Electroacoustic apparatus
US2820161A (en) Electromagnetic vibration generator
US2738386A (en) Magnetostrictive amplifier
US2322722A (en) Permeability tuning system
US2451444A (en) Adjustable wave coupling system