CN101651431B - Cantilever longitudinal-bending composite transducer type cylindrical traveling-wave ultrasonic motor vibrator - Google Patents
Cantilever longitudinal-bending composite transducer type cylindrical traveling-wave ultrasonic motor vibrator Download PDFInfo
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- CN101651431B CN101651431B CN2009100728183A CN200910072818A CN101651431B CN 101651431 B CN101651431 B CN 101651431B CN 2009100728183 A CN2009100728183 A CN 2009100728183A CN 200910072818 A CN200910072818 A CN 200910072818A CN 101651431 B CN101651431 B CN 101651431B
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Abstract
The invention relates to a cantilever longitudinal-bending composite transducer type cylindrical traveling-wave ultrasonic motor vibrator belonging to the technical field of piezoelectric ultrasonic motors and solving the problems that the mechanical output capability of a motor is restricted because the prior ultrasonic motor vibrator adopts a metal elastic body to bond piezoelectric ceramic thin plates to excite, and the mechanical output capability and the controllability of an ultrasonic motor are lowered because a plurality of transducers are simultaneously driven. The cantilever longitudinal-bending composite transducer type cylindrical traveling-wave ultrasonic motor vibrator comprises a cylinder and a cantilever longitudinal-bending composite sandwich transducer which are connected into a whole by two cantilevers, a fastening screw is fixedly screwed with a rear end cover after passing through central through holes of a front end cover and the two cantilevers, four longitudinal vibration piezoelectric ceramic plates are arranged between the two cantilevers, two pairs of bending vibration piezoelectric ceramic plates are respectively arranged between the front end cover and the first cantilever and between the rear end cover and the second cantilever, and the adjacent bending vibration piezoelectric ceramic plates and the adjacent longitudinal vibration piezoelectric ceramic plates have opposite polarization directions. The cantilever longitudinal-bending composite transducer type cylindrical traveling-wave ultrasonic motor vibrator is used for the field of manufacturing ultrasonic motors.
Description
Technical field
The present invention relates to a kind of cantilever longitudinal-bending composite transducer type cylindrical traveling-wave ultrasonic motor oscillator, belong to the piezoelectric ultrasonic motor technical field.
Background technology
Ultrasound electric machine is a kind of ultrasonic vibrational energy of utilizing, and produces the motor of actuating force by the friction coupling.It utilizes the inverse piezoelectric effect of piezoelectric ceramic, in elastomer, motivate the vibration in the supersonic range, form particle movement at surface of elastomer specified point or specific region then, by the coupling of the friction between stator, the rotor microscopic motion of particle is converted to the macroscopic motion of rotor again with particular track.Ultrasound electric machine because have low speed high torque, need not gear, no electromagnetic interference, advantage such as response speed is fast and cut off self-lock, as a kind of piezoelectric actuator application is very widely arranged.
For the simplicity of exiting principle and the simplicity of theoretical analysis method, the piezoelectric ultrasonic motor oscillator adopts the mode of metallic elastic body stickup piezoelectric ceramic thin sheet to encourage mostly at present, and this energisation mode adopts the d of piezoelectric ceramic
31Vibration mode, d
31Vibration mode is the pattern of potsherd stretching vibration along its length, because this vibration mode Tensile strength is low and realize that the mechanical-electric coupling efficient of power conversion is low, pasted the intensity of glue-line and the restriction of fatigue life simultaneously, make the mechanical fan-out capability of ultrasound electric machine be subjected to serious restriction; For the piezoelectric ultrasonic motor that adopts a plurality of transducer drive, because it is in full accord that each transducer is difficult to guarantee in processes such as processing, stickup and assembling, vibration characteristics be there are differences, and then cause the distortion of oscillator surface particle vibration track, reduce the mechanical fan-out capability and the controllability of ultrasound electric machine equally.
Summary of the invention
The objective of the invention is the electromechanics fan-out capability to be restricted for the mode that solves present ultrasonic motor oscillator employing metallic elastic body stickup piezoelectric ceramic thin sheet encourages, and adopt a plurality of transducers to drive simultaneously to make the mechanical fan-out capability of ultrasound electric machine and the problem that controllability all reduces, a kind of cantilever longitudinal-bending composite transducer type cylindrical traveling-wave ultrasonic motor oscillator is provided.
The present invention includes cylinder, it also comprises cantilever longitudinal-bending composite sandwich transducer, cantilever longitudinal-bending composite sandwich transducer is made up of first cantilever, second cantilever, trip bolt, four longitudinal vibration piezoelectric ceramic pieces, four curved piezoelectric ceramic pieces that shake, three insulating cases, seven electrode slices, front end housing and rear end caps
Trip bolt passes front end housing, the central through hole of first cantilever and second cantilever and rear end cap screw fixing, be with two curved piezoelectric ceramic pieces that shake between first cantilever and the front end housing and on the trip bolt between second cantilever and the rear end cap respectively, be with four longitudinal vibration piezoelectric ceramic pieces on the trip bolt between first cantilever and second cantilever, every two adjacent curved shaking between the piezoelectric ceramic piece, first cantilever and curved shake piezoelectric ceramic piece between adjacent with first cantilever, second cantilever and adjacent with second cantilever curved shaking are respectively equipped with an electrode slice between the piezoelectric ceramic piece and between every two adjacent longitudinal vibration piezoelectric ceramic pieces, curved shaking between piezoelectric ceramic piece and electrode slice and the trip bolt, be respectively arranged with insulating case between longitudinal vibration piezoelectric ceramic piece and electrode slice and the trip bolt;
The outer surface of first cantilever, second cantilever and cylinder is made one, and cylinder inner wall is along a plurality of pectination driving gears of circumferential even distribution, and a plurality of pectination driving gears are axially parallel with the central axis of cylinder along cylinder;
Every longitudinal vibration piezoelectric ceramic piece and the every curved piezoelectric ceramic piece that shakes polarize along thickness direction respectively, the polarised direction of two whenever adjacent longitudinal vibration piezoelectric ceramic pieces is opposite, the symmetrical cutting of the every curved piezoelectric ceramic piece that shakes and the polarised direction of a left side half sheet that reconfigures and right half sheet are opposite, every two an adjacent left side half sheet polarised directions of bending the piezoelectric ceramic pieces that shake are opposite, the every two adjacent right side half sheet polarised directions of bending the piezoelectric ceramic pieces that shake are opposite, and the polarised directions of two adjacent with second cantilever with first cantilever respectively curved piezoelectric ceramic pieces that shake are identical.Advantage of the present invention is:
Piezo ceramic element among the present invention adopts sandwich structure, adopts the d of the high mechanical-electric coupling efficient of piezoelectric ceramic
33Vibration mode work, d
33Vibration mode is the pattern of potsherd along the thickness direction stretching vibration, has solved the problem of pasting low, the mechanical fan-out capability difference of piezoelectric ceramic chip piezoelectric ultrasonic motor mechanical-electric coupling efficient; The present invention adopts the excitation that can realize the flexural vibrations of transducer along the curved piezoelectric ceramic piece that shakes of thickness direction polarization, adopts the excitation that realizes the extensional vibration of transducer along the longitudinal vibration piezoelectric ceramic piece of thickness direction polarization; Realize transducer longitudinal vibration natural frequency, curved natural frequency and the curved degeneracy that shakes between the natural frequency of cylinder of shaking of transducer by adjusting structural parameters; Adopt single transducer encourage the trip ripple in cylinder stator, the inconsistent and distortion of the surperficial particle vibration track of oscillator that causes of the vibration that has existed when having avoided adopting a plurality of transducer has improved the mechanical fan-out capability and the controllability of ultrasound electric machine.
But that the present invention has is simple in structure, flexible design, mechanical-electric coupling efficient height, can realize big moment output, stable performance, be easy to control the advantage of producing in serial form.
Description of drawings
Fig. 1 is a perspective view of the present invention; Fig. 2 is the vertical view cutaway drawing of Fig. 1; Fig. 3 is the polarised direction schematic diagram of curved shake piezoelectric ceramic piece and longitudinal vibration piezoelectric ceramic piece in the cantilever bending vibration sandwich converter shown in Figure 2; Fig. 4 is the schematic diagram that the present invention is connected with driving power; Fig. 5～Fig. 8 is that the vibration shape of oscillator of the present invention in a complete vibration period changes circumferentially deploying figure, the vibration shape that is cylinder five rank bending vibration modes changes schematic diagram, wherein Fig. 5 is the oscillator of the present invention vibration shape variation circumferentially deploying figure of one or four/one-period in a complete vibration period, the mode of oscillation of this vibration shape correspondence adopts the extensional vibration excitation cylinder flexural vibration mode of transducer, and this moment, the transducer vibrations state was for shrinking; Fig. 6 is the oscillator of the present invention vibration shape variation circumferentially deploying figure of two or four/one-period in a complete vibration period, and the mode of oscillation of this vibration shape correspondence adopts the flexural vibrations excitation cylinder flexural vibration mode of transducer; Fig. 7 is the oscillator of the present invention vibration shape variation circumferentially deploying figure of three or four/one-period in a complete vibration period, the mode of oscillation of this vibration shape correspondence adopts the extensional vibration excitation cylinder flexural vibration mode of transducer, at this moment, the transducer vibrations state is elongation; Fig. 8 is the oscillator of the present invention vibration shape variation circumferentially deploying figure of four or four/one-period in a complete vibration period, the mode of oscillation of this vibration shape correspondence and Fig. 6 are the flexural vibrations excitation cylinder flexural vibration mode that adopts transducer equally, and flexural vibrations state and Fig. 6 of transducer are opposite.
Embodiment
Embodiment one: present embodiment is described below in conjunction with Fig. 1～Fig. 8, present embodiment comprises cylinder 1, it also comprises cantilever longitudinal-bending composite sandwich transducer 2, cantilever longitudinal-bending composite sandwich transducer 2 is made up of the first cantilever 2-11, the second cantilever 2-12, trip bolt 2-2, four longitudinal vibration piezoelectric ceramic piece 2-3, four curved piezoelectric ceramic piece 2-4 that shake, three insulating case 2-5, seven electrode slice 2-6, front end housing 2-7 and rear end cap 2-8
Trip bolt 2-2 passes front end housing 2-7, central through hole and the rear end cap 2-8 of the first cantilever 2-11 and the second cantilever 2-12 screw fixing, be with two curved piezoelectric ceramic piece 2-4 that shake between the first cantilever 2-11 and the front end housing 2-7 and on the trip bolt 2-2 between the second cantilever 2-12 and the rear end cap 2-8 respectively, be with four longitudinal vibration piezoelectric ceramic piece 2-3 on the trip bolt 2-2 between the first cantilever 2-11 and the second cantilever 2-12, every two adjacent curved shaking between the piezoelectric ceramic piece 2-4, the first cantilever 2-11 and adjacent curved shaking between the piezoelectric ceramic piece 2-4, the second cantilever 2-12 and adjacent curved shaking are respectively equipped with an electrode slice 2-6 between the piezoelectric ceramic piece 2-4 and between every two adjacent longitudinal vibration piezoelectric ceramic piece 2-3, curved shaking between piezoelectric ceramic piece 2-4 and electrode slice 2-6 and the trip bolt 2-2, be respectively arranged with insulating case 2-5 between longitudinal vibration piezoelectric ceramic piece 2-3 and electrode slice 2-6 and the trip bolt 2-2;
The outer surface of the first cantilever 2-11, the second cantilever 2-12 and cylinder 1 is made one, cylinder 1 inwall is along a plurality of pectination driving gear of circumferential even distribution 1-1, a plurality of pectination driving gear 1-1 and cylinder 1 are integral piece, and a plurality of pectination driving gear 1-1 are axially parallel with central axis along cylinder 1;
Every longitudinal vibration piezoelectric ceramic piece 2-3 and the every curved piezoelectric ceramic piece 2-4 that shakes polarize along thickness direction respectively, the polarised direction of two whenever adjacent longitudinal vibration piezoelectric ceramic piece 2-3 is opposite, every two adjacent polarised directions of bending the piezoelectric ceramic piece 2-4 that shake are opposite, the symmetrical cutting of the every curved piezoelectric ceramic piece 2-4 that shakes and the polarised direction of a left side half sheet that reconfigures and right half sheet are opposite, and the polarised direction of two adjacent with the second cantilever 2-12 with the first cantilever 2-11 respectively curved piezoelectric ceramic piece 2-4 that shake is identical.
The height of cylinder 1 is identical with the thickness of cantilever longitudinal-bending composite sandwich transducer 2 in the present embodiment, can make in the process of reality processing technology simpler.
Operation principle: the curved piezoelectric ceramic piece 2-4 that shakes among the present invention is equal with longitudinal vibration piezoelectric ceramic piece 2-3 employing amplitude, frequency is oscillator self resonance frequency, phase difference is ac voltage signal when excitation of+90 °, utilize the extensional vibration of piezoelectric ceramic piece in sandwich converter, to motivate extensional vibration and flexural vibrations, and then be implemented in by two cantilevers that connect cantilever longitudinal-bending composite sandwich transducers 2 and cylinder 1 and motivate two amplitudes on the cylinder 1 and equate, on time and space, all differ the bending vibration modes response of pi/2, two bending vibration modes responses are superimposed upon and form the row ripple on the cylinder 1, cylinder vibration shape circumferentially deploying figure such as Fig. 5～shown in Figure 8, driving gear surface particle produces elliptical trajectory, realizes the macroscopic motion output of rotor by the coupling of the friction between driving gear and the rotor.If adjusting the phase difference of excitation signals is-90 °, can change capable wave line of propagation, finally realize the rotor counter motion.
The cantilever longitudinal-bending composite transducer type cylindrical traveling-wave ultrasonic motor oscillator of present embodiment is when using, referring to shown in Figure 4, at four longitudinal vibration piezoelectric ceramic piece 2-3 centers and the curved electrode slice 2-6 between piezoelectric ceramic piece 2-4 and the cantilever and the common port V of driving power of shaking
0Connect two other electrode slice 2-6 and drive signal V between adjacent longitudinal vibration piezoelectric ceramic piece 2-3
1Connect, at adjacent two curved two electrode slice 2-6 and drive signal V that shake between the piezoelectric ceramic piece 2-4
2Connect.
Embodiment two: the difference of present embodiment and execution mode one is that the cross section of described longitudinal vibration piezoelectric ceramic piece 2-3 and the curved piezoelectric ceramic piece 2-4 that shakes is a rectangle.Other composition and annexation are identical with execution mode one.
Claims (2)
1. cantilever longitudinal-bending composite transducer type cylindrical traveling-wave ultrasonic motor oscillator, it comprises cylinder (1), it is characterized in that: it also comprises cantilever longitudinal-bending composite sandwich transducer (2), cantilever longitudinal-bending composite sandwich transducer (2) is by first cantilever (2-11), second cantilever (2-12), trip bolt (2-2), four longitudinal vibration piezoelectric ceramic pieces (2-3), four curved piezoelectric ceramic pieces (2-4) that shake, three insulating cases (2-5), seven electrode slices (2-6), front end housing (2-7) and rear end cap (2-8) are formed
Trip bolt (2-2) passes front end housing (2-7), the central through hole of first cantilever (2-11) and second cantilever (2-12) and rear end cap (2-8) screw fixing, be with two curved piezoelectric ceramic pieces (2-4) that shake between first cantilever (2-11) and the front end housing (2-7) and on the trip bolt (2-2) between second cantilever (2-12) and the rear end cap (2-8) respectively, be with four longitudinal vibration piezoelectric ceramic pieces (2-3) on the trip bolt (2-2) between first cantilever (2-11) and second cantilever (2-12), every two adjacent curved shaking between the piezoelectric ceramic piece (2-4), between first cantilever (2-11) and the curved piezoelectric ceramic piece that shakes (2-4) adjacent with first cantilever, be respectively equipped with an electrode slice (2-6) between second cantilever (2-12) and the curved piezoelectric ceramic piece that shakes (2-4) adjacent and between every adjacent two longitudinal vibration piezoelectric ceramic pieces (2-3), curved shaking between piezoelectric ceramic piece (2-4) and electrode slice (2-6) and the trip bolt (2-2) with second cantilever, be respectively arranged with insulating case (2-5) between longitudinal vibration piezoelectric ceramic piece (2-3) and electrode slice (2-6) and the trip bolt (2-2);
First cantilever (2-11), second cantilever (2-12) are made one with the outer surface of cylinder (1), cylinder (1) inwall is along a plurality of pectination driving gears of circumferential even distribution (1-1), and a plurality of pectination driving gears (1-1) are axially parallel with the central axis of cylinder along cylinder (1);
Every longitudinal vibration piezoelectric ceramic piece (2-3) and the every curved piezoelectric ceramic piece (2-4) that shakes polarize along thickness direction respectively, the polarised direction of whenever adjacent two longitudinal vibration piezoelectric ceramic pieces (2-3) is opposite, the symmetrical cutting of the every curved piezoelectric ceramic piece (2-4) that shakes and the polarised direction of a left side half sheet that reconfigures and right half sheet are opposite, every two an adjacent left side half sheet polarised directions of bending the piezoelectric ceramic pieces (2-4) that shake are opposite, the every two adjacent right side half sheet polarised directions of bending the piezoelectric ceramic pieces (2-4) that shake are opposite, and the polarised directions of two adjacent with second cantilever (2-12) with first cantilever (2-11) respectively curved piezoelectric ceramic pieces (2-4) that shake are identical.
2. cantilever longitudinal-bending composite transducer type cylindrical traveling-wave ultrasonic motor oscillator according to claim 1 is characterized in that: the cross section of described longitudinal vibration piezoelectric ceramic piece (2-3) and the curved piezoelectric ceramic piece (2-4) that shakes is a rectangle.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009100728183A CN101651431B (en) | 2009-09-08 | 2009-09-08 | Cantilever longitudinal-bending composite transducer type cylindrical traveling-wave ultrasonic motor vibrator |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009100728183A CN101651431B (en) | 2009-09-08 | 2009-09-08 | Cantilever longitudinal-bending composite transducer type cylindrical traveling-wave ultrasonic motor vibrator |
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| Publication Number | Publication Date |
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| CN101651431A CN101651431A (en) | 2010-02-17 |
| CN101651431B true CN101651431B (en) | 2011-06-08 |
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| CN2009100728183A Expired - Fee Related CN101651431B (en) | 2009-09-08 | 2009-09-08 | Cantilever longitudinal-bending composite transducer type cylindrical traveling-wave ultrasonic motor vibrator |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102594199A (en) * | 2012-02-24 | 2012-07-18 | 南京航空航天大学 | Torsional-vibration traveling wave rotary ultrasonic motor based on d15 effect |
| CN103560694B (en) * | 2013-10-11 | 2018-02-06 | 浙江工商大学 | One kind indulges curved compound ultrasonic motor |
| CN106113097A (en) * | 2016-08-19 | 2016-11-16 | 杭州驰飞超声波设备有限公司 | Hand-held composite ultraphonic ripple food carving knife |
| CN109245604B (en) * | 2018-08-08 | 2024-03-29 | 南京航空航天大学 | Sandwich type piezoelectric mechanical arm and driving method thereof |
| CN111146971B (en) * | 2020-02-24 | 2024-05-28 | 南京航空航天大学 | Sandwich type multi-mode composite rotary piezoelectric actuator and working method thereof |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101262188A (en) * | 2008-04-29 | 2008-09-10 | 哈尔滨工业大学 | Vertical vibration sandwich energy converter cylinder stator and ultrasonic electromotor using this stator |
| CN101262186A (en) * | 2008-04-29 | 2008-09-10 | 哈尔滨工业大学 | Vertical bending layer energy converter cylinder stator and ultrasonic electromotor using this stator |
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Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101262188A (en) * | 2008-04-29 | 2008-09-10 | 哈尔滨工业大学 | Vertical vibration sandwich energy converter cylinder stator and ultrasonic electromotor using this stator |
| CN101262186A (en) * | 2008-04-29 | 2008-09-10 | 哈尔滨工业大学 | Vertical bending layer energy converter cylinder stator and ultrasonic electromotor using this stator |
Non-Patent Citations (1)
| Title |
|---|
| JP特开昭64-85583A 1989.03.30 |
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