US3689783A - Ultrasonic transducer with half-wave separator between piezoelectric crystal means - Google Patents

Ultrasonic transducer with half-wave separator between piezoelectric crystal means Download PDF

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Publication number
US3689783A
US3689783A US123204A US3689783DA US3689783A US 3689783 A US3689783 A US 3689783A US 123204 A US123204 A US 123204A US 3689783D A US3689783D A US 3689783DA US 3689783 A US3689783 A US 3689783A
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transducer
crystal
accordance
metal
ultrasonic transducer
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David A Williams
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B06—GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS IN GENERAL
    • B06B—METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY, e.g. FOR PERFORMING MECHANICAL WORK IN GENERAL
    • B06B1/00—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency
    • B06B1/02—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy
    • B06B1/06—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction
    • B06B1/0607—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction using multiple elements
    • B06B1/0611—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction using multiple elements in a pile
    • B06B1/0618—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction using multiple elements in a pile of piezo- and non-piezoelectric elements, e.g. 'Tonpilz'

Definitions

  • An ultrasonic transducer comprises metal from and rear masses, two piezoelectric crystal means sandwiched therebetween, and a' thick metal separator nearly one half wavelength thick between the crystal means to provide improved cooling by conduction of heat from the crystals.
  • the transducer should-have a length equal to a multiple of half wavelengths, and at least two half wavelengths, from end to end.
  • a horn having a length equal to one half wavelength can comprise a part of the transducer, in which case the transducer length equals three half wavelengths.
  • the present invention relates to a novel ultrasonic transducer design, and particularly to such an ultrasonic transducer so constructed as to promote the cooling of the ceramic piezoelectric crystalline elements during operation of the transducer.
  • Ultrasonic transducers which comprise a metal front mass, a metal rear mass, and piezoelectric crystal means comprising one or more piezoelectric crystal elements sandwiched between the masses.
  • piezoelectric crystal means comprising one or more piezoelectric crystal elements sandwiched between the masses.
  • Such separators in the past have been so thin as to impart only limited cooling effect during operation of the transducer. Examples of prior art transducers are shown in U.S.' Pat. Nos. 3,328,610, 3,368,085, and
  • I provide an improved ultrasonic transducer design wherein the metal separator between two piezoelectric crystal means is of great thickness compared to the prior art so as to provide for the absorption and conduction of heat away from the crystal elements during operation of the transducer.
  • Such an improved ultrasonic transducer comprises a metal front mass, a metal rear mass, two piezoelectric crystal means sandwiched between the two masses and located at nodal points, and a metal separator having a thickness nearly equal to a half wavelength between the two crystal means.
  • a horn can extend from the front mass, either integral therewithor attached thereto.
  • the parts advantageously are cylindrical and can be clamped together by a single central bolt, by a number of peripheral bolts, or by a surrounding tension shell.
  • My improvements lie in constructing the transducer to have a length equal to a multiple of half wavelengths, and at least two half wavelengths, from end to end; locating the two crystal means at two difierent nodal points; constructing the metal separator between the two crystal means to be nearly one-half wavelength thick or long; and positioning the positively polarized surfaces of individual crystal elements so that the two crystal means do not buck each other when energized by high frequency alternating current such as 20-40 THE DRAWINGS
  • the Preferred Embodiments I Referring to FIG.
  • an ultrasonic along the line transducer comprising a driver sectioncomposed of a cylindrical rear mass 11, a cylindrical front mass 13, two like-polarized (note arrows) piezoelectric crystal discs 15 and 17 arranged in contact with flat faces of the rear and front masses respectively, and an intermediate metal separator 19 between the two crystal elements and having fiat faces in contact therewith.
  • the front mass 13 is integral with a metal velocity transformer or horn 21 which extends forwardly and is provided with an annular shoulder 23 terminating in an operating end 25 of greatly reduced diameter.
  • the whole assembly is held together by a longitudinal metal bolt 27 which extends through central bores in the assembled parts and is threaded at its forward end to front mass 13, care being taken to insulate the bolt internally from parts 15, 17 and 19 by suitable electrical insulation or by suitable spacing.
  • the front and rear masses 11 and 13 and the separator 19 can be constructed of the same or different metals, such as aluminum, titanium, steel and the like.
  • the crystal elements 15 and 17 can be any of the well known types suchas barium titanate or lead-zirconatetitanate (PZT), which have been purchased in the polarized condition and are mounted with their positively polarized surfaces facing in the same direction as long from end to end, and embodies a separator plate 19 which is nearly one-half wavelength thick, this being many times thicker than the conventional thin separator plate.
  • PZT barium titanate or lead-zirconatetitanate
  • the crystal discs 15 and 17 are located at (and preferably centered on) nodal points N (for maximum effectiveness in driving the transducer). Shoulder 23 also is located at a nodal point N.
  • nodal points N for maximum effectiveness in driving the transducer.
  • a typical transducer in accordance with FIG. 1 had a combined horn 21 and front mass 17 of titanium 3.212 inches long, an aluminum separator 19 2.125 inches long, and a steel back mass 11 0.917 inch long, and was successfully operated at 40 KHz. Crystals are 0.25 inch thick. Horn 25 has a 0.5 inch diameter,,and the rest of the transducer is 1.5 inches in diameter.
  • FIG. 2 there is shown another embodiment comprising similar front and rear masses 11, 13',
  • Each composite crystal means comprises a pair of thin piezoelectric crystal discs 15, '16 and 17, 18, with individual thin metal separator plates 31 and 33 between discs of the respective pairs, and each pair is located at a nodal point.
  • the two separator plates 31 and-33 are electrically connected in parallel to one side of the energizing electrical circuit, and the rear mass 11 and thick separator 19' are connected in parallel to the other side of the energizing circuit.
  • the crystals as purchased from the manufacturer are all polarized the same, and are so positioned in the transducer that the crystals of one pair do not buck the crystals of the other pair.
  • the marked positive surfaces of crystals 15, 16' are positioned facing toward one another and separator 31, while the marked positive surfaces of crystals 17', 18' are positioned facing away from one another and separator 33. Consequently, both crystals of one pair will expand axially when a positive voltage side of an alternating current is applied, while both crystals of the other pair will contract axially; and vice versa when the negative voltage side of an alternating current is applied.
  • positioning can be used as effectively, i.e., the marked positively polarized surfaces of crystals 15', 16 facing away from one another, and the marked positively polarized surfaces of crystals 17', 18' facing toward one another.
  • the construction is similar to that of FIG. 1 except that the intermediate half wave separator between crystals comprises two elements 35 and 37 of equal dimensions but of difierent metals having different densities, which are arranged face-to-face between the crystals.
  • the intermediate half wave separator between crystals comprises two elements 35 and 37 of equal dimensions but of difierent metals having different densities, which are arranged face-to-face between the crystals.
  • light weight titanium or aluminum can be used for the rear half section 35 (constituting the front part of the rear one-half wave section of the entire transducer)
  • a relatively heavy element 37 of steel can be used for the front half section 37 (constituting the rear part of the front one-half wave section of the entire transducer), to produce velocity increase through conservation of momentum.
  • ultrasonic apparatus comprising an ultrasonic transducer T mounted in a suitable support S to permit air cooling of the transducer.
  • the thick half wave metal separator 19" between crystal elements 15" and 17' carries a series of longitudinally extending radial fins 39 on its exterior for dissipating the heat generated in the crystals.
  • circumferential fins or flanges can be used.
  • the transducer T is positioned within a cylindrical housing 40 and is mounted thereon by a mounting plate or flange 41 which is clamped firmly between the front crystal 17" and the rear end of the front mass 13" by means of the central bolt 27".
  • mounting plate 41 can be considered as part of the front mass 13".
  • Mounting plate 41 is connected to housing 40 in any desired way,as by a series of small screws'or bolts 42.
  • the support plate 41 is provided with two series of circumferentially extending overlapping slots 43 and 45 arranged on different circumferences.
  • Cooling is improved by flowing cool air into the housing 40 through an inlet 49 to pass over the fins 19' and out through the slots 43 and 45.
  • Internal air cooling can also be employed as in U.S. Pat. No. 3,555,297 of CW. Pierson; or as in application Ser. No. 118,797
  • Such apparatus can be either stationary or can be designed to move the transducer along, as when performing a splicing operation on plastic sheets (as in U.S. Pat. No. 3,556,912 of Burgo and Pierson).
  • the ultrasonic transducers described above are simple in construction and easily manufactured because all elements are cylinders of equal diameter which are easily machined and can be clamped together by a single bolt. Cooling is greatly improved, especially for continuous duty high power applications such as the splicing of plastic webs.
  • the principles of the invention also apply to ultrasonic transducers which terminate at the front end of the front mass 13, for example as employed for the agitation of cleaning solutions for the for mixing of liquids by fastening the transducer to a tank wall.
  • A is one wavelength in inches, is the longitudinaln bar velocity of sound through the metal (inches/second), and f is the desired resonant frequency in Hz.
  • separator 19 is to be aluminum and the operating frequency is to be 40 KHz,
  • the physical length. of the separator 19 should be shortened to less than M2 to account for the portions of the transducer length occupiedby the driving elements.
  • an ultrasonic transducer comprising a metal front mass, a metal rear mass, two piezoelectric crystal means sandwiched between said masses, and a heat dissipating metal separator between and in contact with said two crystal means
  • the length of said transducer is a multiple of half wavelengths, and at least two half wavelengths, from end to end thereof; wherein said crystal means are located at different nodal points one half wavelength apart; and wherein said metal separator is nearly one half wavelength thick thereby presenting substantial surface area for heat disposal so as to provide for cooler and consequently higher power operation.
  • a metal horn projecting from said front mass, said horn including a terminal portion of reduced diameter, said horn having a length equal to one half wavelength, said horn having a free end located at an 6 f.'l% n uliasoni transducer in accordance with claim 2, said metal separator being a unitary metal body.
  • said metal separator comprising two aligned members formed of metals having different densities.
  • said two crystal means each comprising a single crystal element, each crystal element having a positively polarized surface facing in the same direction as the positively polarized surface of the othercrystal element.
  • said two crystal means comprising first and second pairs of crystal elements, and first and second metal electrical conductors ,therebetween, respectively, the crystal elements of said first pair having positively polarized surfaces facing toward said first conductor, the crystal elements of said second pair having positively polarized surfaces facing away from said second .conductor.
  • a transducer in accordance with claim 2 a support housing enclosing said transducer, and means for blowing cooling gas into said housing and over the exterior of said transducer.
  • a transducer in accordance with claim 2 a support housing enclosing said transducer, at least one perforate mounting plate means clamped between elements of said transducer at at least one nodal point, said mounting plate means I being also fastened to said support housing.
  • an ultrasonic transducer comprising a metal front mass, a metal rear mass, two piezoelectric crystal means sandwiched between said masses, and a heat dissipating metal separator between and in contact with said two crystal means, the improvement wherein the length of said transducer is a multiple of half wavelengths, and at least two half wavelengths, from end to end thereof; wherein said crystal means are located at different nodal points one half wavelength apart and are polarized and arranged to expand and contract in opposite phase relationship; and wherein said metal separator is nearly one half wavelength thick thereby presenting substantial surface area for heat disposal so as to provide for cooler and consequently higher power operation.
  • said crystal means being so polarized and so arranged relative to one another that when energized with high frequency alternating current, expansion of one crystal means occurs at the same time contraction of the other crystal means occurs, and vice versa.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Apparatuses For Generation Of Mechanical Vibrations (AREA)
  • Lining Or Joining Of Plastics Or The Like (AREA)
US123204A 1971-03-11 1971-03-11 Ultrasonic transducer with half-wave separator between piezoelectric crystal means Expired - Lifetime US3689783A (en)

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Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3974681A (en) * 1973-10-23 1976-08-17 Jerry Namery Ultrasonic bubble detector
US4153201A (en) * 1976-11-08 1979-05-08 Sono-Tek Corporation Transducer assembly, ultrasonic atomizer and fuel burner
FR2454351A1 (fr) * 1979-04-19 1980-11-14 Mecasonic Sa Emetteur de machine a souder par ultra-sons
US4352459A (en) * 1979-11-13 1982-10-05 Sono-Tek Corporation Ultrasonic liquid atomizer having an axially-extending liquid feed passage
US4490640A (en) * 1983-09-22 1984-12-25 Keisuke Honda Multi-frequency ultrasonic transducer
DE3521687A1 (de) * 1984-07-05 1986-02-06 ŠKODA koncernový podnik, Pilsen/Plzen Akustischer piezoelektrischer wandler fuer hohe leistungen
EP0245671A1 (en) * 1986-05-09 1987-11-19 Sono-Tek Corporation Central bolt ultrasonic atomizer
US4723708A (en) * 1986-05-09 1988-02-09 Sono-Tek Corporation Central bolt ultrasonic atomizer
US4962330A (en) * 1989-03-21 1990-10-09 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Acoustic transducer apparatus with reduced thermal conduction
US5686776A (en) * 1989-02-10 1997-11-11 Nikon Corporation Ultrasonic motor having high drive efficiency
WO1997045078A1 (en) * 1996-05-29 1997-12-04 Allergan Sales, Inc. Ultrasonic handpiece with multiple piezoelectric elements and heat dissipator
EP0894562A1 (en) * 1997-07-22 1999-02-03 Emerson Electric Co. Ultrasonic apparatus
US20060175935A1 (en) * 1996-09-30 2006-08-10 Bran Mario E Transducer assembly for megasonic processing of an article
US20070034011A1 (en) * 2005-07-25 2007-02-15 Pai-Chi Li Method and apparatus for dynamic focusing in ultrasonic imaging
JP2008529777A (ja) * 2005-02-15 2008-08-07 ウェーバー、ディーター 超音波棒変換器
US20090236938A1 (en) * 2008-02-22 2009-09-24 Piezolnnovations Ultrasonic torsional mode and longitudinal-torsional mode transducer system
US8303613B2 (en) 2007-12-07 2012-11-06 Zevex, Inc. Ultrasonic instrument using langevin type transducers to create transverse motion
US8905689B2 (en) 2010-04-29 2014-12-09 Edison Welding Institute Ultrasonic machining assembly for use with portable devices
EP2845541A1 (en) * 2013-08-29 2015-03-11 Samsung Medison Co., Ltd. Probe for ultrasonic diagnostic apparatus
CN106102622A (zh) * 2014-07-18 2016-11-09 奥林巴斯株式会社 治疗用超声波振子

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2427754A1 (fr) * 1978-06-02 1979-12-28 Commissariat Energie Atomique Capteur d'emission acoustique notamment pour guide d'ondes
JPH03505807A (ja) * 1989-04-18 1991-12-12 ミンスキ　ラディオテフニチェスキ　インスティテュト 電子アコースティック・トランスデューサ
US6434244B1 (en) * 2000-04-26 2002-08-13 Branson Ultrasonics Corporation Electroacoustic converter
DE10027264C5 (de) * 2000-05-31 2004-10-28 Dr. Hielscher Gmbh Ultraschallwandler
RU2452586C1 (ru) * 2011-02-22 2012-06-10 Общество с ограниченной ответственностью "УльтраТехМаш" Ультразвуковой пьезокерамический преобразователь
DE102017122511B3 (de) 2017-09-27 2018-11-22 SCHOTT Diamantwerkzeuge GmbH Kühlsystem für eine Ultraschall-Handbohrmaschine, Ultraschall- Handbohrmaschine sowie Verfahren zum Kühlen einer Schwingungserregereinheit einer Ultraschall-Handbohrmaschine

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2572313A (en) * 1949-03-30 1951-10-23 Rca Corp Magnetostriction device
US3004424A (en) * 1957-10-11 1961-10-17 Sperry Prod Inc Tandem piezoelectric transducers
US3022814A (en) * 1957-02-04 1962-02-27 Jr Albert G Bodine Method and apparatus for sonic bonding
US3117768A (en) * 1960-11-21 1964-01-14 Branson Instr Ultrasonic transducers
US3140859A (en) * 1961-01-17 1964-07-14 Internat Ultrasonics Inc Electroacoustic sandwich transducers
US3183378A (en) * 1960-01-11 1965-05-11 Detrex Chem Ind Sandwich transducer
US3394274A (en) * 1964-07-13 1968-07-23 Branson Instr Sonic dispersing device

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2572313A (en) * 1949-03-30 1951-10-23 Rca Corp Magnetostriction device
US3022814A (en) * 1957-02-04 1962-02-27 Jr Albert G Bodine Method and apparatus for sonic bonding
US3004424A (en) * 1957-10-11 1961-10-17 Sperry Prod Inc Tandem piezoelectric transducers
US3183378A (en) * 1960-01-11 1965-05-11 Detrex Chem Ind Sandwich transducer
US3117768A (en) * 1960-11-21 1964-01-14 Branson Instr Ultrasonic transducers
US3140859A (en) * 1961-01-17 1964-07-14 Internat Ultrasonics Inc Electroacoustic sandwich transducers
US3394274A (en) * 1964-07-13 1968-07-23 Branson Instr Sonic dispersing device

Cited By (33)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3974681A (en) * 1973-10-23 1976-08-17 Jerry Namery Ultrasonic bubble detector
US4153201A (en) * 1976-11-08 1979-05-08 Sono-Tek Corporation Transducer assembly, ultrasonic atomizer and fuel burner
FR2454351A1 (fr) * 1979-04-19 1980-11-14 Mecasonic Sa Emetteur de machine a souder par ultra-sons
US4352459A (en) * 1979-11-13 1982-10-05 Sono-Tek Corporation Ultrasonic liquid atomizer having an axially-extending liquid feed passage
US4490640A (en) * 1983-09-22 1984-12-25 Keisuke Honda Multi-frequency ultrasonic transducer
DE3521687A1 (de) * 1984-07-05 1986-02-06 ŠKODA koncernový podnik, Pilsen/Plzen Akustischer piezoelektrischer wandler fuer hohe leistungen
EP0245671A1 (en) * 1986-05-09 1987-11-19 Sono-Tek Corporation Central bolt ultrasonic atomizer
US4723708A (en) * 1986-05-09 1988-02-09 Sono-Tek Corporation Central bolt ultrasonic atomizer
US5990597A (en) * 1989-02-10 1999-11-23 Nikon Corporation Ultrasonic motor having high drive efficiency
US5686776A (en) * 1989-02-10 1997-11-11 Nikon Corporation Ultrasonic motor having high drive efficiency
US4962330A (en) * 1989-03-21 1990-10-09 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Acoustic transducer apparatus with reduced thermal conduction
WO1997045078A1 (en) * 1996-05-29 1997-12-04 Allergan Sales, Inc. Ultrasonic handpiece with multiple piezoelectric elements and heat dissipator
US5843109A (en) * 1996-05-29 1998-12-01 Allergan Ultrasonic handpiece with multiple piezoelectric elements and heat dissipator
US20060175935A1 (en) * 1996-09-30 2006-08-10 Bran Mario E Transducer assembly for megasonic processing of an article
US20060180186A1 (en) * 1996-09-30 2006-08-17 Bran Mario E Transducer assembly for megasonic processing of an article
US8771427B2 (en) 1996-09-30 2014-07-08 Akrion Systems, Llc Method of manufacturing integrated circuit devices
US7211932B2 (en) * 1996-09-30 2007-05-01 Akrion Technologies, Inc. Apparatus for megasonic processing of an article
US7268469B2 (en) * 1996-09-30 2007-09-11 Akrion Technologies, Inc. Transducer assembly for megasonic processing of an article and apparatus utilizing the same
US8257505B2 (en) 1996-09-30 2012-09-04 Akrion Systems, Llc Method for megasonic processing of an article
US7518288B2 (en) 1996-09-30 2009-04-14 Akrion Technologies, Inc. System for megasonic processing of an article
EP0894562A1 (en) * 1997-07-22 1999-02-03 Emerson Electric Co. Ultrasonic apparatus
CN101142619B (zh) * 2005-02-15 2011-06-08 迪特尔·韦伯 用于在液体中产生超声的超声棒式振荡器
US7688681B2 (en) * 2005-02-15 2010-03-30 Dieter Weber Ultrasonic rod transducer
US20080212408A1 (en) * 2005-02-15 2008-09-04 Dieter Weber Ultrasonic Rod Transducer
JP2008529777A (ja) * 2005-02-15 2008-08-07 ウェーバー、ディーター 超音波棒変換器
US20070034011A1 (en) * 2005-07-25 2007-02-15 Pai-Chi Li Method and apparatus for dynamic focusing in ultrasonic imaging
US8303613B2 (en) 2007-12-07 2012-11-06 Zevex, Inc. Ultrasonic instrument using langevin type transducers to create transverse motion
US20090236938A1 (en) * 2008-02-22 2009-09-24 Piezolnnovations Ultrasonic torsional mode and longitudinal-torsional mode transducer system
US8395299B2 (en) * 2008-02-22 2013-03-12 Piezo-Innocations Ultrasonic torsional mode and longitudinal-torsional mode transducer system
US8905689B2 (en) 2010-04-29 2014-12-09 Edison Welding Institute Ultrasonic machining assembly for use with portable devices
EP2845541A1 (en) * 2013-08-29 2015-03-11 Samsung Medison Co., Ltd. Probe for ultrasonic diagnostic apparatus
CN106102622A (zh) * 2014-07-18 2016-11-09 奥林巴斯株式会社 治疗用超声波振子
EP3170467A4 (en) * 2014-07-18 2018-03-21 Olympus Corporation Ultrasonic vibrator for medical treatment

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GB1379955A (en) 1975-01-08
FR2128798A1 (enExample) 1972-10-20
DE2211774A1 (de) 1972-09-28

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