CN103036472B - Screw-type linear ultrasonic motor - Google Patents
Screw-type linear ultrasonic motor Download PDFInfo
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- CN103036472B CN103036472B CN201210497227.2A CN201210497227A CN103036472B CN 103036472 B CN103036472 B CN 103036472B CN 201210497227 A CN201210497227 A CN 201210497227A CN 103036472 B CN103036472 B CN 103036472B
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Abstract
The present invention discloses a kind of screw-type linear ultrasonic motor, comprise stators and rotators, wherein, described stator comprises stator base and pastes longitudinal vibration piezoelectric chip thereon and torsional vibration piezoelectric chip, described stator base is, cuts out uniform four plane on hollow circular cylinder, for pasting longitudinal vibration piezoelectric chip and torsional vibration piezoelectric chip, described longitudinal vibration piezoelectric chip and torsional vibration piezoelectric chip are all symmetrical installs, and uses in pairs; Described rotor is through stator, and is matched by the internal thread of the outside screw of rotor with two screw drive ends on stator; Described longitudinal vibration piezoelectric chip and torsional vibration piezoelectric chip motivate longitudinal vibration on stator and turn round the compound vibration shaken so that the particle motion trace on stator screw drive end is oval, and stator is rotated by friction-driven rotor, and is translational motion by convert rotational motion. The present invention can realize speed governing and bi-directional drive, and have that cost is low, precision height, make the advantages such as simple, is beneficial to miniatureization and industrialization.
Description
Technical field
The present invention relates to ultrasonic applications device technique field, specifically a kind of screw-type linear ultrasonic motor.
Background technology
Ultrasound electric machine is a kind of piezoelectricity motor, and it utilizes the inverse piezoelectric effect of piezoelectric, electric energy is converted into the vibrational energy of ultrasonic motor stator, then by rubbing effect, vibrational energy is converted into rotation or the translational motion of moving parts. It generally forms primarily of stator, rotor (mover) and pre-pressure mechanism etc. Compared with traditional electrical magneto, supersonic motor has many features and advantage, and such as: compact construction, energy density (torque/quality) is big, is easy to miniatureization; Low-speed and large-torque, it is not necessary to gear reduction, it is possible to realize Direct driver; Motor fast response time, and power-off self-locking can be realized; Position and speed control are good, displacement resolution height; Supersonic motor carries out energy transformation by vibration friction, does not produce magnetic field, also not disturb by external magnetic field in switching process, and anti-electromagnetic interference capability is strong; Quiet noiseless, supersonic motor is operated in supersonic range, owing to not needing the retarding mechanisms such as gear, it is possible to the operation of quiet noiseless; Flexible design, structure formation variation.
Drive surfaces between thread ultrasonic motor stators and rotators is flat of thread, can be directly translational motion by the convert rotational motion of rotor, and the frictional force of the threadingly line needing in conventional threads transmission to overcome is turned into motivating force, there is power amplification, and improve the efficiency of system.
Thread ultrasonic motor has occurred two types, one is the bar-shaped thread ultrasonic motor of swing type, put forward in US Patent No. 7170214B2 by people such as DavidHanderson, it constructs screw drive end at the two ends of a piezoelectric ceramic metal multiple-unit tube stator, the internal thread of screw drive end is coordinated with the outside screw on rotor spindle, excitation signals motivates yaw motion on piezoelectric ceramic metal multiple-unit tube, drive end drives screw thread rotor to rotate, and the translational motion by translating rotation rotor. Stator one-piece construction is longer. Another type is slim expert's ripple screw thread motor, and the people such as Zhou Tieying propose a kind of screw thread motor adopting the piezoelectric ceramic metal compound stator of nut shape to drive in Chinese patent 200510114849 (US Patent No. 7902723B2).
Low-speed and large-torque is an important development direction of Miniature ultrasonic motor. The screw thread motor scheme existed at present, motor is when driving, and the contact of stator and rotor is point cantact or linear contact lay, and it is not very big for exerting oneself. Therefore, the thread ultrasonic motor still needing to develop new principle is with the demand of the relatively large motivating force that meets in small space.
Summary of the invention
The present invention is directed to above shortcomings in prior art, it provides a kind of screw-type linear ultrasonic motor.
The present invention is achieved by the following technical solutions.
A kind of screw-type linear ultrasonic motor, comprise stators and rotators, wherein, described stator comprises stator base and the longitudinal vibration piezoelectric chip being pasted onto on stator base and torsional vibration piezoelectric chip, described stator base is, cuts out uniform four plane on hollow circular cylinder, for pasting longitudinal vibration piezoelectric chip and torsional vibration piezoelectric chip, described longitudinal vibration piezoelectric chip and torsional vibration piezoelectric chip are all symmetrical installs, and uses in pairs; Described rotor is through stator, and is matched by the internal thread of the outside screw of rotor with two screw drive ends on stator; Described longitudinal vibration piezoelectric chip and torsional vibration piezoelectric chip motivate longitudinal vibration on stator and turn round the compound vibration shaken so that the particle motion trace on stator screw drive end is oval, and stator is rotated by friction-driven rotor, and is translational motion by convert rotational motion.
Described stator forms a rank longitudinal vibration by longitudinal vibration piezoelectric chip and torsional vibration piezoelectric chip and the compound vibration mode shaken is turned round as operation mode in two rank, a described rank longitudinal vibration mode and two rank torsional oscillation mode frequencies are close, with same frequency excitation signal, motor is encouraged, thus the phase differential that vertical, the torsion that motivate on stator are vibrated is close to 90 degree.
Described torsional vibration piezoelectric chip, its upper surface electrode is divided into left and right two portions, lower surface is by full electrode, and bond together with stator base, torsional vibration piezoelectric chip left and right two portions direction of polarization is contrary, applies identical alternation actuation signal, it is attached to the both sides of stator base, when monolithic uses, piezoelectricity sheet encourages two rank flexural deformations, then the flexural deformation of torsional vibration piezoelectric chip is converted into when using in pairs two rank torsional deformations of stator base.
Described longitudinal vibration piezoelectric chip, through-thickness polarizes, and its upper and lower surface is by full electrode, and bond together with stator base, it is attached to the both sides of stator base, when using in pairs, apply identical alternation actuation signal, thus on stator base, motivate a rank longitudinal vibration distortion.
The outside screw tooth type of described rotor is trilateral, trapezoidal, rectangle or circular arc.
Described stator and/or rotor are provided with friction pair.
Described longitudinal vibration piezoelectric chip and torsional vibration piezoelectric chip are piezoceramic material or piezoelectric monocrystal.
Screw-type linear ultrasonic motor provided by the invention, becomes motivating force by the frictional force between the screw thread originally needing to overcome in conventional linear drives scheme, and is translational motion by the convert rotational motion of rotor; Stator adopts SMD structure, and technique is simple, be easy to miniatureization; Owing to the contact between stator and rotor is face contact, bigger motivating force can be provided, and speed governing and bi-directional drive can be realized, have that cost is low, precision height (micron is nano-precision even), make the advantages such as simple. The unusual effect of the program overcomes in conventional longitrorse driving pattern, and torsional vibration piezoelectric chip is difficult to the difficulty of miniatureization, is beneficial to miniatureization, and the relatively large moment that can provide stable in small space exports.
Accompanying drawing explanation
Fig. 1 is longitudinal vibration ceramic plate and modification schematic diagram thereof, and wherein, (a) is direction of polarization figure, and (b) is distortion figure, and in figure, 11 is longitudinal vibration piezoelectric chip, and 12,13 is electrode surface, and 14 is direction of polarization, and 15 is direction of an electric field;
Fig. 2 is two subregion twisting vibration ceramic plate and modification schematic diagram thereof, and (a) figure is subregion and direction of polarization figure, and (b) figure is distortion figure, in figure, 21 is torsional vibration piezoelectric chip, and 22,23,24 is electrode surface, 25,26 is direction of polarization, and 27,28 is direction of an electric field;
Fig. 3 is the structural representation of stator, and in figure, 31 is stator base, and 32 is screw drive end, and 33 is internal thread;
Fig. 4 is two rank torsion modes schematic diagram of stator;
Fig. 5 is a rank longitudinal vibration mode schematic diagram of stator;
Fig. 6 is the structural representation of this motor, and in figure, 61 is rotor, and 62 is the outside screw on rotor.
Embodiment
Do embodiments of the invention to illustrate in detail below: the present embodiment is implemented under premised on technical solution of the present invention, gives detailed enforcement mode and concrete operating process, but protection scope of the present invention is not limited to following embodiment.
The present embodiment comprises stators and rotators, wherein, stator comprises stator base 31 and pastes longitudinal vibration piezoelectric chip 11 thereon and torsional vibration piezoelectric chip 21, stator base 31 is, hollow circular cylinder cuts out uniform four plane, for pasting longitudinal vibration piezoelectric chip 11 and torsional vibration piezoelectric chip 21, longitudinal vibration piezoelectric chip 11 and torsional vibration piezoelectric chip 21 are all symmetrical installs, and uses in pairs; Rotor 61 is through stator, and is matched by the internal thread 33 of the outside screw 62 of rotor with two screw drive ends 32 on stator; Longitudinal vibration piezoelectric chip 11 and torsional vibration piezoelectric chip 21 motivate longitudinal vibration on stator and turn round the compound vibration shaken so that the particle motion trace on stator screw drive end 32 is oval, and stator is rotated by friction-driven rotor 61, and is translational motion by convert rotational motion.
Stator is by the excitation of longitudinal vibration piezoelectric chip 11 and torsional vibration piezoelectric chip 21, form a rank longitudinal vibration and two rank and turn round the compound vibration mode shaken as operation mode, one rank longitudinal vibration mode and two rank torsional oscillation mode frequencies are close, by same frequency, motor is encouraged, thus the phase differential that vertical, the torsion that motivate on stator are vibrated is close to 90 degree.
The upper surface electrode of torsional vibration piezoelectric chip 21 is divided into left and right two portions, lower surface is full electrode, and bond together with stator base 31, torsional vibration piezoelectric chip about 21 two portions direction of polarization is contrary, apply identical alternation actuation signal, it is attached to the both sides of stator base 31, when monolithic uses, torsional vibration piezoelectric chip 21 encourages two rank flexural deformations, then the flexural deformation of torsional vibration piezoelectric chip 21 is converted into when using in pairs two rank torsional deformations of stator base 31.
The upper and lower surface of longitudinal vibration piezoelectric chip 11 is by full electrode, and bonds together with stator base 31, is attached to the both sides of stator base 31, when using in pairs, applies identical alternation actuation signal, thus motivates a rank longitudinal vibration distortion on stator base 31.
The outside screw 62 tooth type of rotor 61 is trilateral, trapezoidal, rectangle or circular arc.
Stator and/or rotor 61 are provided with friction pair.
Longitudinal vibration piezoelectric chip 11 and torsional vibration piezoelectric chip 21 are piezoceramic material or piezoelectric monocrystal.
It is specially, stator comprises two panels longitudinal vibration piezoelectric chip 11, two panels torsional vibration piezoelectric chip 21, stator base 31 and two screw drive ends 32, two panels longitudinal vibration piezoelectric chip 11 symmetry is attached to the both sides of stator base 31, for encouraging a rank longitudinal vibration of stator, two panels torsional vibration piezoelectric chip 21 symmetry is attached to the both sides of stator base 31, for encouraging two rank twisting vibrations of stator. Two screw drive ends 32 there is threaded central aperture 33. One rank longitudinal vibration model frequency and the two rank torsion modes Frequency Design of stator are identical, during excitation, alternation actuation signal (sinusoidal or square wave) motivates phase differential as far as possible close to longitudinal vibration and the twisting vibration of 90 degree on stator, but the phase differential of actuation signal might not be 90 degree. On stator screw drive end, the motion track of particle is oval. Rotor 61, through stator, it has outside screw 62, matches with the internal thread 33 on the screw drive end 32 on stator. Stator is rotated by friction-driven rotor 61, and is translational motion by convert rotational motion, it is achieved high precision drives.
Longitudinal vibration piezoelectric chip 11 polarizes along thickness direction 14, upper and lower surface 12,13 by electrode, as shown in Figure 1. When applying an alternating electric field 15 between upper/lower electrode 12,13, the distortion elongated or shortened along its length can be produced.
Torsional vibration piezoelectric chip 21 upper surface 22,24 and lower surface 23 are by electrode, and as shown in Figure 2, wherein upper surface electrode is divided into left half 24 and right half 22. The polarization of bending vibration piezoelectric ceramic piece 21 the right and left is contrary, and left side direction of polarization 25, direction, 26, the right is contrary. During excitation, upper surface 22,24 connects identical alternating voltage, lower surface 23 ground connection, can motivate the flexural deformation as shown in Fig. 2 (b) on piezoelectric ceramics. This torsional vibration piezoelectric chip 21 is attached to the both sides of cylindrical metal substrate, and electrode surface 23 and metallic matrix bond together. After using in pairs, flexural deformation will be converted into the torsional deformation of stator.
Stator base 31 is the hollow circular cylinder of four sides trimming, cuts out uniform four plane on the cylinder, for pasting piezoelectricity sheet. Stator base 31 is made up of copper or other metallic substance. The longitudinal vibration piezoelectric chip 11 that two panels symmetry is installed applies alternation actuation signal, a rank longitudinal vibration as shown in Figure 5 will be motivated on stator. The torsional vibration piezoelectric chip 21 that two panels symmetry is installed applies alternation actuation signal, two rank twisting vibrations as shown in Figure 4 will be motivated on stator. If being designed to identical by a rank longitudinal vibration model frequency of stator and two rank torsion mode vibrational frequencies, encouraged by motor by same frequency, then the compound vibration shaken is turned round on a rank longitudinal vibration and two rank that can motivate stator. Phase differential vertical, that turn round vibration is 90 degree, and the performance of motor is best. Therefore, it should the phase differential of adjustment two-phase actuation signal so that vertical, to turn round vibration phase differential is as far as possible close to 90 degree.
Two screw drive ends 32 are arranged on the two ends of stator base, and screw drive end centre hole is threaded hole, has internal thread 33. Stator, under the effect of the two-phase actuation signal of same frequency, forms Hybrid transducer vibration, and now the motion track of the particle on internal thread 33 is oval.
Rotor, through stator, it has outside screw 62, matches with the internal thread 33 on the screw drive end 32 on stator. Stator is rotated by friction-driven rotor 61, and is translational motion by convert rotational motion.
Friction materials is had, it is possible to the upper friction materials of process simultaneously on stators and rotators, forms friction pair on stator or on rotor.
The form of thread of screw drive end 32 can be any one in triangle thread, trapezoidal thread, square thread, circular thread.
Above specific embodiments of the invention are described. It is understood that the present invention is not limited to above-mentioned particular implementation, those skilled in the art can make various distortion or amendment within the scope of the claims, and this does not affect the flesh and blood of the present invention.
Claims (6)
1. a screw-type linear ultrasonic motor, it is characterized in that, comprise stators and rotators, wherein, described stator comprises stator base and the longitudinal vibration piezoelectric chip being pasted onto on stator base and torsional vibration piezoelectric chip, and described stator base is, hollow circular cylinder cuts out uniform four plane, for pasting longitudinal vibration piezoelectric chip and torsional vibration piezoelectric chip, described longitudinal vibration piezoelectric chip and torsional vibration piezoelectric chip are all symmetrical installs, and uses in pairs; Described rotor is through stator, and is matched by the internal thread of the outside screw of rotor with two screw drive ends on stator; Described longitudinal vibration piezoelectric chip and torsional vibration piezoelectric chip motivate longitudinal vibration on stator and turn round the compound vibration shaken so that the particle motion trace on stator screw drive end is oval, and stator is rotated by friction-driven rotor, and is translational motion by convert rotational motion;
Described stator is by the excitation of longitudinal vibration piezoelectric chip and torsional vibration piezoelectric chip, form a rank longitudinal vibration and two rank and turn round the compound vibration mode shaken as operation mode, a described rank longitudinal vibration mode and two rank torsional oscillation mode frequencies are close, with same frequency excitation signal, motor is encouraged, thus the phase differential that vertical, the torsion that motivate on stator are vibrated is close to 90 degree.
2. screw-type linear ultrasonic motor according to claim 1, it is characterized in that, described torsional vibration piezoelectric chip, its upper surface electrode is divided into left electrode and right electrode two portions, lower surface is a monoblock electrode, the left electrode of torsional vibration piezoelectric chip upper surface and right electrode two portions direction of polarization are contrary, apply identical alternation actuation signal; Described torsional vibration piezoelectric chip is two panels, symmetry is attached on the two sides of stator base, when using a slice torsional vibration piezoelectric chip, torsional vibration piezoelectric chip encourages two rank flexural deformations, when using the two rank torsional deformations that then flexural deformation of torsional vibration piezoelectric chip is converted into during two panels torsional vibration piezoelectric chip stator base in pairs.
3. screw-type linear ultrasonic motor according to claim 1, it is characterised in that, described longitudinal vibration piezoelectric chip through-thickness polarizes, and its upper and lower surface is a monoblock electrode; Described longitudinal vibration piezoelectric chip is two panels, and bonds together with stator base, and symmetry is attached on the two sides of stator base, when using two panels longitudinal vibration piezoelectric chip in pairs, applies identical alternation actuation signal, thus motivates a rank longitudinal vibration distortion on stator base.
4. screw-type linear ultrasonic motor according to any one of claim 1 to 3, it is characterised in that, the outside screw tooth type of described rotor is trilateral, trapezoidal, rectangle or circular arc.
5. screw-type linear ultrasonic motor according to any one of claim 1 to 3, it is characterised in that, described stator and/or rotor are provided with friction pair.
6. screw-type linear ultrasonic motor according to any one of claim 1 to 3, it is characterised in that, described longitudinal vibration piezoelectric chip and torsional vibration piezoelectric chip are piezoceramic material or piezoelectric monocrystal.
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CN201210497227.2A CN103036472B (en) | 2012-11-28 | 2012-11-28 | Screw-type linear ultrasonic motor |
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CN107707150A (en) * | 2017-11-09 | 2018-02-16 | 南京航空航天大学 | The ultrasound electric machine and method of work of screw thread pair driving based on bending vibration modes |
CN109398685B (en) * | 2018-11-13 | 2024-05-28 | 南京航空航天大学 | Patch type piezoelectric driving rotor wing flying device |
CN112217417B (en) * | 2019-07-09 | 2024-07-02 | 重庆邮电大学 | Three-foot plane three-degree-of-freedom piezoelectric resonance self-actuating mechanism and excitation method thereof |
CN112953298B (en) * | 2021-03-26 | 2022-09-13 | 重庆第二师范学院 | Flat ultrasonic motor |
CN116690627B (en) * | 2023-07-31 | 2023-11-07 | 季华实验室 | Mechanical clamping jaw and excitation method thereof |
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CN1667934A (en) * | 2005-04-08 | 2005-09-14 | 清华大学 | Composite ultrasonic micromotor with slotted metal square column piezoelectric sheet |
CN1964175A (en) * | 2006-11-24 | 2007-05-16 | 清华大学 | A screw thread driving polyhedral supersonic micro motor with pre-pressure mechanism |
CN101022257A (en) * | 2007-03-20 | 2007-08-22 | 哈尔滨工业大学 | Double-driving foot sandwich converter type longitudinal and bending linear ultrasonic motor |
CN201075845Y (en) * | 2007-09-05 | 2008-06-18 | 清华大学 | Screwed cap type ultrasound electric machine |
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JP2012196094A (en) * | 2011-03-17 | 2012-10-11 | Olympus Corp | Piezoelectric actuator |
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Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1667934A (en) * | 2005-04-08 | 2005-09-14 | 清华大学 | Composite ultrasonic micromotor with slotted metal square column piezoelectric sheet |
CN1964175A (en) * | 2006-11-24 | 2007-05-16 | 清华大学 | A screw thread driving polyhedral supersonic micro motor with pre-pressure mechanism |
CN101022257A (en) * | 2007-03-20 | 2007-08-22 | 哈尔滨工业大学 | Double-driving foot sandwich converter type longitudinal and bending linear ultrasonic motor |
CN201075845Y (en) * | 2007-09-05 | 2008-06-18 | 清华大学 | Screwed cap type ultrasound electric machine |
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