US3777189A - Acoustic energy transmission device - Google Patents

Acoustic energy transmission device Download PDF

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Publication number
US3777189A
US3777189A US00250395A US3777189DA US3777189A US 3777189 A US3777189 A US 3777189A US 00250395 A US00250395 A US 00250395A US 3777189D A US3777189D A US 3777189DA US 3777189 A US3777189 A US 3777189A
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United States
Prior art keywords
transducer
guide
fibers
end portion
combination
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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
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US00250395A
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English (en)
Inventor
D Skinner
J Thompson
R Whittaker
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ABB Inc USA
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Westinghouse Electric Corp
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Assigned to ABB POWER T&D COMPANY, INC., A DE CORP. reassignment ABB POWER T&D COMPANY, INC., A DE CORP. ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: WESTINGHOUSE ELECTRIC CORPORATION, A CORP. OF PA.
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R15/00—Details of measuring arrangements of the types provided for in groups G01R17/00 - G01R29/00, G01R33/00 - G01R33/26 or G01R35/00
    • G01R15/14—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks
    • G01R15/26—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using modulation of waves other than light, e.g. radio or acoustic waves
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/18—Methods or devices for transmitting, conducting or directing sound
    • G10K11/24—Methods or devices for transmitting, conducting or directing sound for conducting sound through solid bodies, e.g. wires

Definitions

  • ABSTRACT An apparatus for transmitting energy in the form of acoustic energy from one location to another, the energy being supplied at one location to the transmitting apparatus from an acoustic electric energy source through an electromechanical transducer and supplied at the other location by the transmitting apparatus to an electrical load through a second electromechanical transducer.
  • transmitters of this type were energized with energy derived from the transmission line.
  • energy storage devices charged by this derived energy were provided to energize the transmitter during periods when the transmission line was deenergized.
  • the energy storage devices while an improvement over the direct energy deriving devices left much to be desired because of the life expectancy of the storage devices and the difficulty of their replacement. Also there was a limit to energy which could be stored and to the time periods that the storage device could maintain the transmitter in operating condition with the transmission line deenergized.
  • FIG. I is an abbreviated view of a power supplying apparatus for delivering power from a potential supply which is substantially that of earth to an energy utilizing device operating at high potential with respect to earth potential and which embodies the invention;
  • FIG. 2 is an enlarged view of one end portion of a wave guide of FIG. 1 showing in greater detail the attachment of the piezoelectric transducer;
  • FIG. 3 is a view of a modified form of a wave guide embodying the invention.
  • FIG. 4 is an enlarged view of an end portion of a modified form of wave guide with a piezoelectric transducer attached;
  • FIG. 5 is a graph showing the relationship, at three different frequencies, between the percentage of glass vs the attenuation of the wave guide in DB/meter;
  • FIG. 6 is a view of a modified form of transducer for vibrating the wave guide
  • FIG. 7 is a sectional view taken substantially along the line VII-VII of FIG. 6 looking in the direction of the arrows;
  • FIG. 8 is a partial view showing the electrical connections to the wafers used in the modified form of FIGS. 6 and 7;
  • FIG. 9 is a partial view of a further modified form of transducer for vibrating the wave guide
  • FIG. 10 is a sectional view taken substantially along the line X-X of FIG. 9 looking in the direction of the arrows;
  • FIG. 11 is a partial view showing the electrical connections to the wafers used in the modified form of FIGS. 9 and 10.
  • the numeral 1 designates generally a transmission line conductor, the current in which, is monitored by a current transformer 2 which modulates a transmitter 4.
  • the transmitter 4 transmits a signal indicative of one or more characteristics of the current in line 1 to a receiver 6 at ground or earth potential.
  • the details of the transmitter 4 and of the receiver 6 may take any desired form.
  • a preformed foam is a type in which the output signal is transmitted as light through a light pipe diagrammatically illustrated by the dash line 8.
  • Power for energizing the transmitter 4 is derived from the power oscillator 10 the output of which is coupled to the input terminals 12, 14 and 14A of a transducer- 16 through a matching transformer 18. If desired, the operating frequency may be modulated by means of the feedback network 20 to provide a maximum power transmission to the elongated rod-like wave guide 22.
  • the transducer 16 comprises two annular piezoceramic wafers l9 and 19A having their end walls silvered and being longitudinally polarized.
  • the adjacent silvered end walls are connected to the input terminal 12 while the outwardly facing silvered end walls are connected to the input terminals 14 and 14A.
  • the wafer 19 is assembled in opposite polarization to the wafer 19A so that when the input terminals are energized with an alternating potential both wafers increase and decrease in thickness together.
  • a suitable material for the wafers l9 and 19A is lead zirconate titanate sold by Gulton Industries, Inc., Metuchen, New Jersey, designated by them as I-IDT-3l. This material is strong in compression but weak in tension and must therefore by prevented from exerting a tensile force.
  • the wafers l9 and 19A have first and second outer surfaces 24 and 26 clamped between the transducer head 28 and the transducer tail 33 by the nut 36 screwthreaded on a through bolt 30 and which compresses a belleville washer 31 against the outer end wall of the tail 33.
  • the bolt 30 extends axially through the transducer 16 and is screwthreadedly secured to the end wall 29 of the head 28.
  • the outer silvered end surfaces 24 and 26 of the wafers l9 and 19A are insulated from the head 28 and tail 33 by the insulating washers 34.
  • the head member 28 is cup-shaped and receives the adjacent end portions of the wave guide 22 which is suitably secured therein with the end portion of the guide 22 adjacent its bottom end wall 29.
  • the nut 36 threadedly carried by the bolt 30 stresses the resilient belleville washer 38 and resiliently clamps the wafers to the end wall 29.
  • the washer 38 must exert sufficient resilient force to prevent the transducer 16 from exerting a tensile force.
  • the tail member 33 acts as 2 reaction mass for the transducer 16, giving it something to push against.
  • the stress bolt 30 and belleville washer 38 have greater compliance than the transducer 16. Very little vibration energy exists on the stress bolt 30 beyond the tail nut 36.
  • the tail member 33 should be massive with respect to the head member 28. A weight ratio of greater than 2 to l is desirable and should be at least equal to l to l.
  • the upper head member 28 couples the upper transducer 16 to the upper end portion of the wave guide 22.
  • the guide 22 is suspended from its upper end by means of a nut 40 threaded on the end of the upper bolt which extends through an aperture in a supporting member 42.
  • the lower bolt 30 may if desired loosely extend through a locating hole in a lower supporting member 44. With the guide so supported, it is held with its ends restrained but not clamped. It will be apparent its lower end may move vertically relative to the member 44 to permit expansion and contraction of the guide 22 due to temperature changes or otherwise.
  • the wave guide material should be inorganic electrically non-conducting of high density and have a low loss factor.
  • a very suitable material is pyrex glass which has a'density of about 2,500 Kg/cubic meter or the more expensive quartz may be used. Such a material in long lengths is subject to breakage and is difficult to handle, however it may be usable under some conditions as for example when there is a straight vertical path between the supports 40 and 44 as illustrated in FIG. 1 and protected against being hit. r
  • FIGS. 3 and 4 illustrate a form of the invention in which a plurality of smaller diameter rods 122 are coupled in parallel between two heads 128.
  • This form as illustrated in FIG. 3 is more flexible than the single rod 22 illustrated in FIGS. 1 and '2 and may be coiled for its easy transporting and threading around any obstructions which would prevent a straight line run of rod.
  • 12 rods of one-quarter inch diameter would have approximately the same total crosssectional area as a single rod of seven-eighths inch diameter and could be bent to a lesser radius.
  • FIG. 4 illustrates an assembly of four one-quarter inch rods in one dimension with three one-quarter inch rods in the second dimension secured to a transducer 16A which except for the head 128 is identical to the transducer 16. If great flexibility is desired for bending this rod in a single direction the twelve one-quarter inch rods could be in a row. This would, of course, decrease the flexibility for bending in the plane of the row and increase the flexibility in the plane perpendicular to the row. We have found that the acoustic energy can be transmitted along a flexed or curved rod or group of rods without substantially decreasing the power thereof below that of the straight run rod or rods.
  • the driving force would be 8.15 pounds per square inch peak and the movement of the head member 28 or 128 as the case may be would be 2.4 X 10 inches peak. If the frequency of the power source is reduced to 10 kHz the movement or displacement would be increased to 4.8 X 10 inches peak with the same driving force of 8.15 pounds per square inch. For most practical installations the driving or source frequency should be somewhat above the frequency normally heard by persons or above 16 kHz. Therefore 20 kHz or more is a preferred frequency since no audible noise will be produced.
  • the absolute power carrying capacity can be increased by increasing the rod area up to a diameter which approaches 0.3 times the wavelength of the acoustical energy. At diameters above this the propagation begins to deviate substantially from the longitudinal mode in that the Poissons contraction and expansion couples sideway motions into the main mode.
  • the choice of frequency depends upon the number of factors. If it is too low, the rod will not propagate a longitudinal mode because of the easily excited other modes such as flexure. If the rod is maintained in tension lower frequencies can be transmitted but the problems associated with the maintenance of the proper tension, even of a straight rod due, to temperature and other environmental conditions are troublesome and such frequencies are in the audible range and objectionable from that viewpoint. Also at the lower frequencies the flexing resonance at bends or curvatures of the rod tend to decrease the transmitted power and increase the losses which unduly heat these portions of the rod or rods.
  • the transducer 168 of FIGS. 6-8 have segmented wafers 1 19 and 119A each of which comprise four segments 119B, 119C, 119D and 119E.
  • the segments are polarized longitudinally of the transducer 168 and are insulated from the head 128A and tail 133A by the annular insulating washers 134A and 1348 respectively.
  • the transducer has an annular section 135 intermediate the segmented wafer 119 and 119A and insulated therefrom by annular insulating washers 136A and 1368.
  • a first annular insulating spool 137A has one end surface cemented to the head 128A and its other end surface cemented to the adjacent end surface of the section 135 by a high tensile epoxy such as epon 6.
  • a second annular in'sulating spool 1378 is cemented to the section 135 and tail 133A.
  • a suitable material for the spools is polytetrafluoroethylene.
  • the segments have their longitudinally extending side walls covered with an electrically conducting material 120 such as silver and they are longitudinally polarized.
  • the radially extending end walls unlike the wafers 19 and 19A are not covered with electrically conducting material.
  • the segments 119C and 119E are polarized in a first longitudinal direction while the segments 1198 and 119D are polarized in the second or opposite longitudinal direction.
  • the adjacent longitudinally-extending' side walls of the segments l19C-l 19D and 11915-1198 are electrically connected together by a conductor 121A which in turn is connected to a lead wire 122.
  • the adjacent longitudinally extending side walls of the segments ll9B-l19C and 119D-l19E are electrically connected together by a conductor 123A which is in turn connected to a lead wire 124.
  • the segments of the segmented wafer 119 are similarly connected to the conductors 122 and 124 by the conductors 121 and 123.
  • the segments 1198 and 119D are polarized in one longitudinal direction while the segments 119C and 119E are polarized in the opposite longitudinal direction.
  • the transducer When an alternating potential is applied to the leads 122 and 124 the transducer will deliver a rotational vibration to its head 128A which is cemented to one end portion of the wave guide 122A which may be of the type shown in FIG. 2 or FIG. 4; the type shown in FIG. 2 being illustrated.
  • the transducer 16C comprises a head 128B cemented to one end portion of a wave guide 1228 and at least one segmented wafer 11% sandwiched between the tail 1333 and head 1288 and insulated therefrom by the insulating washers 134C and 136C.
  • the segmented wafer 119F comprises two segments 1196 and 1191-1. These segments are longitudinally polarized and their outer end walls are coated with an electrically conducting material such as silver 1208 as are the wafers 19 and 19A.
  • the outer end walls of the segments 119G are energized at the opposite polarity to the segments 1191-1 as illustrated in FIG. 11 so that when the leads 1238 and 1248 are energized with an alternating potential one of the segments 119G and 1191-1 will tend to expand longitudinally and the other of the segments 1191-1 or 119G will tend to contrast longitudinally thereby giving a rocking vibratory motion to the wave guide 1228 for transmitting power therealong to the receiving transducer.
  • a spool 137C is positioned concentrically of the wafer 119F and has its opposite end walls cemented to the head 128B and the tail 133C.
  • the spool 137C like the spools 137A and B are preferably of insulating resilient material such as polytetrafluoroethylene.
  • segmented wafer 119F While only a single segmented wafer 119F is illustrated it will be apparent that a plurality thereof may be used. It will also be possible to reverse the polarization of the segments 1190 and 1191-1 and to energize the surface B thereof adjacent the washer 134C from the same lead 1238 or 1248 and the other surfaces 120B adjacent washer 136C from the other of the leads 1248 or 1238.
  • An acoustic energy transmission device comprising, first and second electro-acoustic transducers, each said transducer including an electrical circuit and a force exerting surface, an elongated substantially void free wave guide having first and second end portions, said guide comprising not less than 40% of inorganic electrically non-conducting low mass density fibers and a plastic binder bonding said fibers together, first means holding said surface of said first transducer to said first end portion and second means holding said surface of said second transducer to said second end portion.
  • each saidholding means includes a supporting member secured tothe end portion of said guide with which it is associated, each saidholding means further including means supported by its said supporting member and resiliently holding the said surface of the associated said transducer against the associated said end portion of said guide.

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  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Apparatuses For Generation Of Mechanical Vibrations (AREA)
  • Transducers For Ultrasonic Waves (AREA)
  • Measurement Of Velocity Or Position Using Acoustic Or Ultrasonic Waves (AREA)
US00250395A 1972-05-04 1972-05-04 Acoustic energy transmission device Expired - Lifetime US3777189A (en)

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US25039572A 1972-05-04 1972-05-04

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US (1) US3777189A (enrdf_load_html_response)
BR (1) BR7303197D0 (enrdf_load_html_response)
CA (1) CA977865A (enrdf_load_html_response)
DE (1) DE2321989A1 (enrdf_load_html_response)
ES (1) ES414351A1 (enrdf_load_html_response)
FR (1) FR2183500A5 (enrdf_load_html_response)
GB (1) GB1434794A (enrdf_load_html_response)
IT (1) IT998104B (enrdf_load_html_response)

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3937990A (en) * 1974-05-28 1976-02-10 Winston Ronald H Ultrasonic composite devices
FR2402877A1 (en) * 1977-12-06 1979-04-06 Westinghouse Electric Corp Detector and locator for electrical discharges - uses acoustic waveguides connected to piezoceramic element in inductive enclosed windings
US4158169A (en) * 1977-12-06 1979-06-12 Westinghouse Electric Corp. Corona testing apparatus including acoustic waveguides for transmitting acoustic emissions from electrical apparatus
US4158168A (en) * 1977-12-06 1979-06-12 Westinghouse Electric Corp. Acoustic waveguides for sensing and locating corona discharges
US4352038A (en) * 1980-02-19 1982-09-28 Moreton Neal S Acoustical transmission wave guide assembly for predicting failure of structured members
EP0246460A1 (de) * 1986-05-05 1987-11-25 Siemens Aktiengesellschaft Verfahren zur Messung elektrischer oder magnetischer Wechselfelder und Anordnung zur Durchführung des Verfahrens
EP0480078A1 (de) * 1990-10-08 1992-04-15 Siemens Aktiengesellschaft Messvorrichtung mit nichtelektrischer Signal- und Energieübertragung
US5200666A (en) * 1990-03-09 1993-04-06 Martin Walter Ultraschalltechnik G.M.B.H. Ultrasonic transducer
EP0580304A1 (en) * 1992-07-22 1994-01-26 Hewlett-Packard Company Intracavity ultrasound diagnostic probe using fiber acoustic waveguides
US5400788A (en) * 1989-05-16 1995-03-28 Hewlett-Packard Apparatus that generates acoustic signals at discrete multiple frequencies and that couples acoustic signals into a cladded-core acoustic waveguide
ES2118042A1 (es) * 1996-10-03 1998-09-01 Univ Catalunya Politecnica Transductor piezoelectrico para medida de altas tensiones y su procedimiento de funcionamiento.
US5998908A (en) * 1996-05-09 1999-12-07 Crest Ultrasonics Corp. Transducer assembly having ceramic structure
US6653760B1 (en) 1996-05-09 2003-11-25 Crest Ultrasonics Corporation Ultrasonic transducer using third harmonic frequency

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS54162280A (en) * 1978-06-13 1979-12-22 Nippon Denshi Kogyo Kk Transmission cable of ultrasoniccwave device
GB8713314D0 (en) * 1987-06-06 1987-07-08 Brush Switchgear Current transformers
GB8819163D0 (en) * 1988-08-12 1988-09-14 Ass Elect Ind Current transformer

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3140859A (en) * 1961-01-17 1964-07-14 Internat Ultrasonics Inc Electroacoustic sandwich transducers
US3166840A (en) * 1961-06-28 1965-01-26 Aeroprojects Inc Apparatus and method for introducing high levels of vibratory energy to a work area
US3173034A (en) * 1960-09-16 1965-03-09 Singer Inc H R B Ultrasonic device
US3546498A (en) * 1969-06-13 1970-12-08 Univ Ohio Curved sonic transmission line
US3584327A (en) * 1969-04-04 1971-06-15 Fibra Sonics Ultrasonic transmission system
US3591862A (en) * 1970-01-12 1971-07-06 Ultrasonic Systems Ultrasonic motor transmission system

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3173034A (en) * 1960-09-16 1965-03-09 Singer Inc H R B Ultrasonic device
US3140859A (en) * 1961-01-17 1964-07-14 Internat Ultrasonics Inc Electroacoustic sandwich transducers
US3166840A (en) * 1961-06-28 1965-01-26 Aeroprojects Inc Apparatus and method for introducing high levels of vibratory energy to a work area
US3584327A (en) * 1969-04-04 1971-06-15 Fibra Sonics Ultrasonic transmission system
US3546498A (en) * 1969-06-13 1970-12-08 Univ Ohio Curved sonic transmission line
US3591862A (en) * 1970-01-12 1971-07-06 Ultrasonic Systems Ultrasonic motor transmission system

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3937990A (en) * 1974-05-28 1976-02-10 Winston Ronald H Ultrasonic composite devices
FR2402877A1 (en) * 1977-12-06 1979-04-06 Westinghouse Electric Corp Detector and locator for electrical discharges - uses acoustic waveguides connected to piezoceramic element in inductive enclosed windings
US4158169A (en) * 1977-12-06 1979-06-12 Westinghouse Electric Corp. Corona testing apparatus including acoustic waveguides for transmitting acoustic emissions from electrical apparatus
US4158168A (en) * 1977-12-06 1979-06-12 Westinghouse Electric Corp. Acoustic waveguides for sensing and locating corona discharges
US4352038A (en) * 1980-02-19 1982-09-28 Moreton Neal S Acoustical transmission wave guide assembly for predicting failure of structured members
EP0246460A1 (de) * 1986-05-05 1987-11-25 Siemens Aktiengesellschaft Verfahren zur Messung elektrischer oder magnetischer Wechselfelder und Anordnung zur Durchführung des Verfahrens
US5400788A (en) * 1989-05-16 1995-03-28 Hewlett-Packard Apparatus that generates acoustic signals at discrete multiple frequencies and that couples acoustic signals into a cladded-core acoustic waveguide
US5200666A (en) * 1990-03-09 1993-04-06 Martin Walter Ultraschalltechnik G.M.B.H. Ultrasonic transducer
EP0480078A1 (de) * 1990-10-08 1992-04-15 Siemens Aktiengesellschaft Messvorrichtung mit nichtelektrischer Signal- und Energieübertragung
EP0580304A1 (en) * 1992-07-22 1994-01-26 Hewlett-Packard Company Intracavity ultrasound diagnostic probe using fiber acoustic waveguides
US5998908A (en) * 1996-05-09 1999-12-07 Crest Ultrasonics Corp. Transducer assembly having ceramic structure
US6653760B1 (en) 1996-05-09 2003-11-25 Crest Ultrasonics Corporation Ultrasonic transducer using third harmonic frequency
ES2118042A1 (es) * 1996-10-03 1998-09-01 Univ Catalunya Politecnica Transductor piezoelectrico para medida de altas tensiones y su procedimiento de funcionamiento.

Also Published As

Publication number Publication date
FR2183500A5 (enrdf_load_html_response) 1973-12-14
GB1434794A (en) 1976-05-05
CA977865A (en) 1975-11-11
IT998104B (it) 1976-01-20
BR7303197D0 (pt) 1974-07-11
DE2321989A1 (de) 1973-11-15
ES414351A1 (es) 1976-02-01

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AS Assignment

Owner name: ABB POWER T&D COMPANY, INC., A DE CORP., PENNSYLV

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:WESTINGHOUSE ELECTRIC CORPORATION, A CORP. OF PA.;REEL/FRAME:005368/0692

Effective date: 19891229