喜歡就充值下載吧。。資源目錄里展示的文件全都有，，請(qǐng)放心下載，，有疑問(wèn)咨詢QQ:414951605或者1304139763 ======================== 喜歡就充值下載吧。。資源目錄里展示的文件全都有，，請(qǐng)放心下載，，有疑問(wèn)咨詢QQ:414951605或者1304139763 ======================== Ultrasonics 38 (2000) 7276www.elsevier.nl/locate/ultrasOne-dimensional longitudinaltorsional vibration converterwith multiple diagonally slitted partsJiromaru Tsujino*, Tetsugi Ueoka, Kenichi Otoda, Atsushi FujimiFaculty of Engineering, Kanagawa University, Yokohama 221-8686, JapanAbstractFor increasing the available vibration velocity of the one-dimensional longitudinaltorsional vibration converter, a new typeof complex vibration converter with multiple slitted parts installed in the positions avoiding longitudinal nodal positions alongthe converter for decreasing the maximum vibration stress level at the vibration nodal part was studied. The free end of theconverter vibrates in an elliptical or circular locus. Complex vibration systems with elliptical to circular or rectangular to squareloci can be applied effectively for various high-power applications, including ultrasonic welding of metal or plastics, ultrasonicwire bonding of IC, LSI and electronic devices, and also ultrasonic motors. The converter with multiple slitted parts was improvedin the vibration stress level and the quality factor compared with the converter with single slitted part. 2000 Elsevier ScienceB.V. All rights reserved.Keywords: Circular vibration locus; Complex vibration; Complex vibration ultrasonic welding; Longitudinaltorsional vibration converter;Ultrasonic motor; Ultrasonic plastic welding; Vibration converter with diagonal slits1. Introductionvibration characteristics because the maximum vibrationstress along the converter is decreased in comparison tothe converter with a slitted part, and the maximumComplex vibration systems with elliptical to circularvibration amplitude of the converter increases signifi-or rectangular to square loci are effective for variouscantly. Vibration locus, and vibration velocity and phasehigh-power applications. A one-dimensional longitudi-distributions along the converter were measured by twonaltorsional vibration converter with a slitted part atlaser Doppler vibrometers. The new-type converterslongitudinal vibration nodal area driven by a longitudi-were used for ultrasonic plastic welding and ultrasonicnal vibration system is useful for high-power applica-motors.tions including ultrasonic welding of various materials,The maximum available vibration velocity increasedultrasonic wire bonding of bonding of IC, LSI andsignificantly with the new converter. Welding character-electronic devices, and also ultrasonic motors 14. Aistics of plastic materials were improved by the complexnew type of converter with multiple slitted parts, forvibration converter.improving the vibration characteristics and increasingThe longitudinal and torsional vibration amplitudesthe available vibration velocity of the converter, isof a 15 mm diameter of a new converter for an ultrasonicstudied. The slitted parts are installed in multiple posi-motor increased to about 12 mm (peak-to-zero value)tions avoiding longitudinal nodal positions along thefrom 6 mm with a former converter under the sameconverter for decreasing the maximum vibration stressdriving voltage 60 Vrms at 55 kHz.level at the vibration nodal part. Using multiple slittedThe converter with multiple slitted parts was foundparts, the maximum vibration stress along a converterto be effective for improving the vibration characteristicsdecreases and the quality factor increases, and theand increasing the available complex vibration velocity.maximum vibration amplitude increases significantly atthe same driving voltage 5. The converter has superior2. Configurations of vibration converters* Corresponding author. Tel.: +81-45-481-5661;Configurations of two examples of the vibrationfax: +81-45-491-7915.E-mail address: tsujinocc.kanagawa-u.ac.jp (J. Tsujino)converters 20 mm in diameter and 79 mm in length, with0041-624X/00/$ - see front matter 2000 Elsevier Science B.V. All rights reserved.PII: S0041-624X(99)00175-473J. Tsujino et al. / Ultrasonics 38 (2000) 72764. Complex vibration ultrasonic plastic welding4.1. Vibration characteristics of a complex vibrationconvertersFig. 2 shows the relationship between driving fre-quency and longitudinal and torsional vibration velocityof a complex vibration system with the vibration con-verter (a). The driving voltage is kept constant at20 Vrms. Longitudinal and torsional vibration velocitieshave maximum values at different frequencies at around26.3 and 26.4 kHz. The elliptical locus is obtained atthe free edge of the converter.Torsional and radial vibration velocity distributionsat 26.8 kHz along a complex vibration converter withFig. 1. Various one-dimensional longitudinal to torsional vibrationdouble slitted parts (a) and (b) are shown in Fig. 3. Oneconverters with double slitted parts.torsional vibration velocity nodal part is within a leftslitted area, and the vibration velocities have maximumvalues at the free edge.The radial vibration velocity distribution along aslitted parts that were installed avoiding a longitudinalcomplex vibration converter with double slitted partsnodal part, are shown in Fig. 1. The cylindrical longitu-dinaltorsional vibration converters, made of aluminumalloy (JISA7075B), had two slitted parts on both sidesof a longitudinal vibration nodal part at its circumfer-ence. The converters were driven by a longitudinalvibration source. Various converters with (a) differentand (b) the same angle diagonally slitted parts weremade in the trials. The vibration converter part had 18diagonal slits of 45 or 135, 10 mm width and 0.5 mmwidthwerecut alongitscircumferenceusinganelectrosparking machine. The slit depth was altered from1.0 to 3.0 mm. The free edge part of the convertervibrated longitudinally and torsionally and vibrated inan elliptical locus.Fig. 2. Torsional and radial vibration velocity distributions along com-plex vibration converters (a) and (b). Driving voltage: 20 Vrms.3. Vibration characteristics of the converters with twoslitted partsThe free admittance loops of the total vibrationsystems with the converters Fig. 1(a) and (b) weremeasured. The quality factor and motional admittance,|Ymo|, of the vibration system with a converter withdifferent angle slitted parts (a) and the same angle slittedparts (b) were about 600 and 30 mS under weldingconditions of two 1.0 mm thick polypropyrene sheetswith a static pressure of 890 kPa. The admittance loopsof the vibration system with the converters show singlecircular shapes because the resonance frequencies of thelongitudinal and torsional vibrations are close. Thequality factors and motional admittances of the bothFig. 3. Relationship between driving frequency, and longitudinal andsystems are large. Elliptical loci were obtained at thetorsional vibration velocity of a complex vibration system with a vibra-tion converter (A). Driving voltage: 20 Vrms.free edges of the converters.74J. Tsujino et al. / Ultrasonics 38 (2000) 7276(a) is also shown in Fig. 3 (dotted line). A radialand double slitted parts. In the case of the converterwith single slitted part, the slitted part is positioned atvibration velocity maximum position means a longitudi-a nodal position of the longitudinal vibration along thenal vibration nodal position, and the longitudinal nodalcylindrical longitudinaltorsional vibration converters.position is positioned between two slitted parts. TheOn the contrary, in the case of the converter with twotwo slitted areas exist out of the longitudinal nodalslitted parts, the slitted parts are positioned avoidingposition where the vibration stress has a maximum valuethe longitudinal vibration nodal position. The converteralong the converter.with diagonal slits is driven by a longitudinal vibrationsource of two piezoelectric ceramic (leadzircontita-4.2. Welding characteristics of complex vibrationnate; PZT) disks, 15 mm in diameter and 5.0 mm inultrasonic plastic weldingthickness. The vibration converter slitted part has 12diagonal slits of 45 or 135 and 0.5 mm in width and 10The relationship between welding time, specimenor 5 mm in length, cut by an electrosparking machinedeformed thickness at the welded parts and the weldalong the circumference of these converters fabricatedstrength of the lapped polypropyrene sheets (1.0 mm infrom aluminum alloy (JISA7075B). The slit depths ofthickness), welded using a 27 kHz complex vibrationthe 15 mm diameter converter are altered from 1.5 tosystem with a converter (a) and (b), is shown in Fig. 4.3.5 mm. The free edge of the converter vibrates longitu-The weld strengths obtained by the system with con-dinally and torsionally and vibrates in an elliptical locus.verter (a) are larger than those with a converter (b).The PZT longitudinal vibration transducers, a longi-The welding time required becomes shorter using thetudinal vibration rod with a flange for supporting thevibration system (a) with a larger torsional vibrationmotor and a slitted cylinder are clamped by a connectingcomponent. The decrease in specimen deformed thick-bolt. The driving part of the converter and the rotorness at the welded parts roughly corresponds to thepart are statically pressed using corned disk springs byobtained weld strength. Specimens were welded in aa center bolt and nuts. The driving surfaces of theshorter welding time using a complex vibration systemconverter (JISA7075B) and the rotor (steel: SKD-61 orcompared with a longitudinal vibration system. ComplexSK-4: tempered) are ground to be flat and smooth usingvibration is effective for ultrasonic welding of plastic15002000 mesh polishing powder.materials as for metal materials.5.2. Vibration characteristics of 15 mm diameterultrasonic motors5. Ultrasonic motors with a longitudinaltorsionalconverterThe longitudinal and torsional vibration amplitudesat the free edge of these converters were measured by5.1. Configuration of ultrasonic motorstwo laser Doppler vibrometers when the driving fre-quency was altered. These converters have near-reso-The configurations of the ultrasonic motors andnance frequencies of the longitudinal and torsionalvibration converters, 15 mm in diameter, are shown invibrations similar to Fig. 2. The largest longitudinalFig. 5. Fig. 5(a) and (b) show the configurations ofvibration amplitudes of the converter of single and two15 mm diameter motors using a converter with singleslitted parts without a rotor part were about 6 and12 mm (peak-to-zero value) at frequencies of 5055 kHz.The largest longitudinal vibration amplitudes of theseconverters with a rotor part are about 3 and 9 mm atfrequencies near to 55 kHz. The largest vibration ampli-tudes of a converter with double slitted parts are abouttwo to three times compared with the amplitudes of aconverter with single slitted part.5.3. Vibration loci at the driving surface of the converterIn these cases, the longitudinal vibration is partiallyconverted to torsional vibration at the slitted parts, andthe cylinder part of the converter vibrates longitudinallyand torsionally. The vibration locus at the free edge isdetermined by the vibration phase difference betweenFig. 4. Relationship between welding time, deformed weldment heightthese vibrations. Vibration loci at the driving surfacesand weld strength of the lapped polypropyrene sheets (1.0 mm in thick-of longitudinaltorsional converters were measuredness), weldedusing a 27 kHz complexvibration systemwith a converter(a) and (b).using two laser Doppler vibrometers (20 MHz) that75J. Tsujino et al. / Ultrasonics 38 (2000) 7276Fig. 5. Configurations of 15 mm diameter ultrasonic motors using a longitudinaltorsional vibration converter with single slitted part (a) anddouble slitted parts (b).detect longitudinal and torsional vibrations indepen-length of the ultrasonic motor of 15 mm diameter in thedriving frequency 55.1 kHz (without a rotor) anddently. The vibration locus is shown on a digital memoryoscilloscope screen as a Lissajous figure. Fig. 6 shows54.26 kHz (with a rotor). The vibration locus amplitudeat the driving surfaces of converter decreases slightlythe vibration loci at the driving surfaces of converterswith double slitted parts of 3.3 mm depth and 5 mmwhen the ultrasonic motor rotates.Fig. 6. Vibration loci at a driving part of a 15 mm diameter converter with and without a rotor part.76J. Tsujino et al. / Ultrasonics 38 (2000) 72766. Conclusionmaterials.The15 mmdiameterultrasonicmotor,together with a converter with double slitted parts,rotated at over 300 rpm.For increasing the available vibration velocity of thecomplex vibration converter, a new type of converterThe converters with multiple slitted parts were foundto be effective for improving the vibration characteristicswith multiple slitted parts was studied.This converter has multiple slitted parts that areand increasing the available complex vibration velocity.installed in multiple positions, avoiding nodal positionsalong the converter for decreasing the maximum vibra-tion stress level at the vibration node part. The weldingReferencescharacteristics of ultrasonic plastic welding using com-plex vibrations were studied. Also, 15 mm diameter1 J. Tsujino, T. Ueoka, T. Shiraki, K. Hasegawa, R. Suzuki, M.ultrasonic motors using converters with double slittedTakeuchi, Proc. Int. Congress on Acoustics (1995) 447450.parts were tested.2 J. Tsujino, Proc. IEEE 1995 Ultrasonics Symp., IEEE, New York,The longitudinal vibration nodal part was located1996, pp. 10511060.between two slitted parts of the converters. The driving3 J. Tsujino, T. Uchida, K. Yamano, T. Iwamoto, T. Ueoka, Proc.2nd World Congress on Ultrasonics, Yokohama, Japan (1997)surface of the converter and the ultrasonic motor with152153.double slitted parts vibrated at higher vibration velocities4 J. Tsujino, T. Uchida, K. Yamano, T. Iwamoto, T. Ueoka, Proc.than those with a single slitted part at the same driv-IEEE1997UltrasonicsSymp.,IEEE,NewYork,1998,ing voltage.pp. 855860.The converter with double slitted parts significantly5 J. Tsujino, T. Ueoka, Proc. IEEE 1999 Ultrasonics Symp., IEEE,New York, 1999, pp. 723728.improved the ultrasonic welding characteristics of plastic