JPH06319271A - Ultrasonic driving device - Google Patents

Abstract

PURPOSE:To provide an ultrasonic driving device by mounting a resonance plate on the side of a ring-shaped piezoelectric vibrator to enlarge and transmit progressive wave. CONSTITUTION:An ultrasonic vibrator 1 is mounted in the projecting part 5a of a case 5 and a fan-shaped resonance plate 2 is bonded to the ultrasonic vibrator 1 and formed into a circle so that a stator 4 is constituted. Also, a rotating shaft 7 is secured to the center of the cylindrical part 6 of a rotor 8 and rotatably mounted by bearings 9, 10 mounted in the case 5, and a spring 12 is provided between the rotor 8 and a thrust bearing 11 so that the slider 6a of the cylindrical part 6 of the rotor 8 is pressure-welded to the resonance plate 2 of the stator 4. In an ultrasonic driving device constituted in this manner, progressive wave generated in the ultrasonic vibrator 1 by the resonance plate 2 is enlarged and transmitted so that the rotor 8 can be driven efficiently.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic drive device for expanding a traveling wave by mounting a resonance plate on a side surface of a thin ring-shaped piezoelectric vibrator.

[0002]

2. Description of the Related Art The applicant of the present invention forms electrodes on both sides of a ring-shaped vibrator or a disk-shaped vibrator, forms a groove in the center of these electrodes to divide each electrode into two, and determines the angle of the groove. And an ultrasonic drive device in which traveling waves are generated on the side surface and both sides of the ring-shaped oscillator or the disc-shaped oscillator by applying an AC voltage to one electrode of each of the two divided electrodes on both sides. Proposed (Japanese Patent Laid-Open No. 64-30477)
(See the official gazette).

[0003]

By the way, since the efficiency of this ultrasonic driving device is as low as about 5%, it has been desired to improve the efficiency.

[0004]

DISCLOSURE OF THE INVENTION The present invention is an ultrasonic drive system in which electrodes are provided on both sides of a ring-shaped piezoelectric vibrator, and ring-shaped piezoelectric vibrators that generate a traveling wave by applying an AC voltage to the electrodes are provided. In the device, a plurality of fan-shaped resonance plates protruding from the diameter of the ring-shaped piezoelectric vibrator are fixed to one surface of the ring-shaped piezoelectric vibrator in a circular shape to form a stator, and the rotor is pressed against the side surface of the resonance plate. It is a thing.

[0005]

According to the present invention, the piezoelectric vibrator is provided with four divided electrodes provided on the side surface of the ring-shaped piezoelectric vibrator, and AC power having a phase difference of 90 degrees is supplied to each two of the four divided electrodes. A traveling wave is generated at the end face or side face of the.

This traveling wave is transmitted to a fan-shaped resonator plate fixed to the side surface of the piezoelectric vibrator. Since this resonator plate protrudes from the diameter of the ring-shaped piezoelectric vibrator, each fan-shaped resonance plate is resonated. The plate becomes a traveling wave resonance member, and the amplitude is expanded.

Therefore, when the rotor is pressed against the resonance plate, the driving body is driven by the amplified traveling wave, and the efficiency thereof is expanded from 5% to 20%.

[0008]

1 is a plan view of a stator of an ultrasonic driving apparatus according to an embodiment of the present invention, and FIG. 2 is a side view of FIG.
A large number of fan-shaped resonance plates 2 are attached to the side surfaces of the resonator plate 2 with ring-shaped synthetic resin 3 in such a manner that the inner ends 2a thereof are substantially aligned with the holes 1a of the piezoelectric vibrator 1, and the outer ends of the resonance plates 2 are Is 2
b is projected from the diameter of the piezoelectric vibrator 1 and has a substantially circular shape to form the stator 4.

FIG. 3 is a plan view of a stator of an ultrasonic wave drive device according to another embodiment of the present invention, and FIG. 4 is a side view of FIG. 3, showing a fan-shaped side surface of the piezoelectric vibrator 1 as in the above embodiment. The plurality of resonance plates 2 are aligned so that the inner ends 2a thereof are substantially aligned with the holes 1a of the piezoelectric vibrator 1, and a plurality of fan-shaped resonance plates 2 are bonded with a synthetic resin 3a to form the outer ends of the resonance plates 2. 2b protrudes from the diameter of the piezoelectric vibrator 1 and is formed into a substantially circular shape.
Is formed.

FIG. 5 is a block diagram of an ultrasonic driving device using these stators 4, FIG. 6 is a plan view of a rotor of the ultrasonic driving device of FIG. 5, and a rotor 8 has a cylindrical portion 6 and a stator. The slider 6a contacting the resonance plate 2 of No. 4 is composed of a sliding member, the rotating shaft 7 is fixed to the center of the cylindrical portion 6 of the rotor 8, and the case 5 is provided in the hole 1a of the piezoelectric vibrator 1. Of the rotor 8 is rotatably supported by bearings 9 and 10 provided on the case 5, and the thrust bearing 11 is attached to the rotary shaft 7.
Is mounted, and the leaf spring 12 provided between the thrust bearing 11 and the rotor 8 presses the slider 6a of the cylindrical portion 6 of the rotor 8 against the resonance plate 2 of the stator 4.

In the ultrasonic driving apparatus of this embodiment having the above-described structure, the slider 6a of the rotor 8 is pressed against the resonance plate 2 by the leaf spring 12, so that the rotor 8 is moved by the expanded traveling wave. It efficiently rotates, its rotation torque is large, and it is possible to efficiently drive other driving bodies connected to the rotating shaft 7.

FIG. 7 is a sectional view of an ultrasonic wave drive device according to still another embodiment of the present invention, in which 1 is an ultrasonic transducer, 2 is a resonance plate,
5 is a case, 6 is a cylindrical portion, 7 is a rotating shaft, 8 is a rotor,
Reference numerals 9 and 10 are bearings, and the constructions thereof are the same as those in the above-mentioned embodiment, so that the description thereof will be omitted. I'm using it.

In this embodiment thus constructed, the rotor 8 is efficiently rotated by the traveling wave expanded by the resonance plate 2 similarly to the above-described embodiment, the torque is large, and the rotor 8 is connected to the rotating shaft 7. The driving body can be efficiently driven.

Further, in the ultrasonic driving device of the present embodiment, the ring-shaped piezoelectric vibrator 1 has a thickness of 1 mm to 1.5 mm, and the resonator plate 2 has a thickness of 1 mm to 2 mm. Therefore, it can be made very small, and such an ultrasonic drive device stops as soon as the power supply is cut off, so it does not require braking means like an ordinary electric motor, It can be used to rotate a volume or other control equipment.

In the above-described embodiment, the gap between the two resonance plates is aligned with the electrode dividing line of the piezoelectric vibrator 1, and a large number of fan-shaped resonance plates 2 are arranged on the electrodes of the piezoelectric vibrator 1. Although it is insulated by the ring-shaped synthetic resin 3 and the synthetic resin 3a for adhesion even if it is directly adhered to the electrode, a thin insulating plate for treating aluminum with alumite is provided on the electrode, or a thin insulating plate. The fan-shaped resonator plate 2 can be insulated even by bonding, and the resonator plate can be integrally molded by this method.

In the above embodiment, the resonator plate 2 is formed in a fan shape, but rectangular resonator plates may be arranged in a circle so that the outer circumference is circular.

FIG. 8 is a plan view of an ultrasonic wave driving device according to another embodiment of the present invention, and FIG. 9 is a side view of FIG. 8, in which circular fan-shaped resonance plates 2 are provided on both sides of a ring-shaped piezoelectric vibrator 1. Glued or
The inner end is fixed by the synthetic resin 3 to form the stator 13, and the stator 13 is fixed by inserting the protrusion 5a of the case 5 into the hole 1a of the piezoelectric vibrator 1.

Further, a large number of sliders 14 (eight in the figure) provided with protrusions 14a so as to be sandwiched between the resonance plates 2 on both sides of the piezoelectric vibrator 1 are grooves formed in the opposing portions of the protrusions 14a. 14
By inserting the rubber band 15 into b, the stator 1
However, instead of the rubber band 15, a ring-shaped spring may be used to press the slider 14 against the resonance plate 2 of the stator 13.

Further, two projections 16 are fixed to the side surface of the slider 14 with a space therebetween, and between the projections 16, a plurality of supports 17 are radially supported in the vicinity of one end thereof. The other end of the body 17 is fixed to the rotary shaft 7 to form a rotor 18, and the rotary shaft 7 of the rotor 18 is supported by bearings 9 and 10 provided in the case 5.

In the ultrasonic driving device of this embodiment having the above-described structure, the rotor 18 is rotated with a higher torque by the enlarged traveling wave of the resonant plates 2 on both sides of the piezoelectric vibrator 1, and the efficiency is high. There are advantages.

FIG. 10 is a plan view of an ultrasonic drive device according to another embodiment of the present invention with the cover opened, and FIG. 11 is a side sectional view of FIG. The resonance plate 19 is symmetrically bonded to form the stator 20, and the piezoelectric vibrator 1 of the stator 20 is fixed to the case 5 by inserting the projecting portion 5a of the case 5 into the hole 1a.

Further, one resonance plate 19 of this stator 20
The portion projecting from the piezoelectric vibrator 1 is inserted into the groove 21a of the driving body 21 that moves linearly, and the driving body 21 is pressed against the resonance plate 19 of the stator 20 by the springs 22 and 23.

In the ultrasonic driving device of this embodiment having the above-described structure, the rectangular resonator plate 19 magnifies the traveling wave of the piezoelectric vibrator 1 to drive the driving body 21, so that the driving body 21 is driven.
Can be driven with high torque.

In the above embodiment, the disassembled resonator plates 2 are integrated to form a stator. However, as shown in FIG. 11, notches 25 are radially formed from the outer end 24a toward the inner end 24b. A stator can be formed in the same manner by bonding the resonator plate 24, which is provided and left between the cuts 25, which is connected at the inner end portion 24b, to the piezoelectric vibrator 1.

When the resonance plate 24 is directly adhered to the electrodes of the piezoelectric vibrator 1, the electrodes are short-circuited, so the resonance plate 24 is coated with an insulating film.

[0026]

As described above, in the ultrasonic driving device of the present invention, by adhering the resonance plate to the thin ring-shaped piezoelectric vibrator, the traveling wave generated in the piezoelectric vibrator is generated at the end face of the resonance plate. Since it is expanded, the efficiency is improved from 5% to 20%, and when the power supply is stopped, it immediately stops, so it can be used as it is for positioning control or rotation of the volume etc. There is an advantage.

[Brief description of drawings]

FIG. 1 is a plan view of a stator of an ultrasonic wave drive device according to an embodiment of the present invention.

FIG. 2 is a side view of a stator of the ultrasonic drive device of FIG.

FIG. 3 is a plan view of a stator of an ultrasonic drive device according to another embodiment of the present invention.

FIG. 4 is a side view of a stator of the ultrasonic drive device of FIG.

FIG. 5 is a side sectional view of an ultrasonic drive device according to still another embodiment of the present invention.

FIG. 6 is a plan view of the rotor of FIG.

FIG. 7 is a side sectional view of an ultrasonic driving device according to still another embodiment of the present invention.

FIG. 8 is a plan view of a stator of an ultrasonic drive device according to another embodiment of the present invention.

9 is a side sectional view of the ultrasonic wave drive device of FIG. 7. FIG.

FIG. 10 is a plan view of an ultrasonic drive device according to another embodiment of the present invention with a cover open.

FIG. 11 is a side sectional view of the ultrasonic driving device.

FIG. 12 is a plan view of a resonator plate according to another embodiment of the present invention.

[Explanation of symbols]

 1 ring-shaped piezoelectric vibrator 2 resonance plate 3, 3a synthetic resin 4, 13 stator 5 case 6 cylindrical portion 6a, 14 slider 7 rotary shaft 8 rotor 9, 10 bearing 11 thrust bearing 12 spring 15 rubber band 16 protrusion 17 support 18 rotor 19 resonance plate 20 stator 21 driver 22 and 23 spring 24 resonance plate

Claims (9)

[Claims] 1. An ultrasonic drive device comprising electrodes provided on both surfaces of a ring-shaped piezoelectric vibrator, and a ring-shaped piezoelectric vibrator for applying an alternating voltage to the electrodes to generate a traveling wave. A plurality of fan-shaped or rectangular resonance plates protruding from the diameter of the ring-shaped piezoelectric vibrator are fixed to one surface of the ring-shaped piezoelectric vibrator in a circular shape to form a stator, and the rotor is pressed against the side surface of the resonance plate. Ultrasonic drive device. 2. The ultrasonic drive device according to claim 1, wherein the resonator plate is integrally formed in a ring shape by bonding an inner end portion thereof with a ring-shaped synthetic resin. 3. The ultrasonic drive device according to claim 2, wherein the resonator plate is coated with an insulating film. 4. A ring-shaped piezoelectric vibrator, wherein an electrode is provided on both surfaces of the ring-shaped piezoelectric vibrator, and the ring-shaped piezoelectric vibrator is provided to apply an AC voltage to the electrodes to generate a traveling wave. A disk protruding from the diameter of the ring-shaped piezoelectric vibrator is formed by forming a notch at the inner end from the outer end to form a fan shape or a rectangular shape in which the inner end is connected and coated with an insulating film. An ultrasonic drive device, comprising a stator fixed to one side in a circular shape, and a rotor being pressed against a side surface of the resonance plate. 5. An ultrasonic wave drive device, comprising electrodes provided on both surfaces of a ring-shaped piezoelectric vibrator, and a ring-shaped piezoelectric vibrator for applying an alternating voltage to the electrodes to generate a traveling wave. A plurality of fan-shaped resonance plates protruding from the diameter of the ring-shaped piezoelectric vibrator are fixed to both side surfaces of the stator in a circular shape, and the outer ends of the resonance plates on both side surfaces of the piezoelectric vibrator of the stator. An ultrasonic drive device comprising: a rotor including a slider that is pressed against a ring-shaped elastic member and a support body that is connected to a rotating shaft. 6. The resonator plate is integrally formed in a ring shape by adhering an inner end portion thereof with a synthetic resin.
The ultrasonic drive device described. 7. The ultrasonic drive device according to claim 5, wherein the ring-shaped elastic member is a rubber band. 8. The ultrasonic drive device according to claim 5, wherein the elastic member of the ring is a ring-shaped spring. 9. An ultrasonic wave drive device, comprising electrodes provided on both surfaces of a ring-shaped piezoelectric vibrator, and a ring-shaped piezoelectric vibrator for applying an alternating voltage to the electrodes to generate a traveling wave. A plurality of rectangular or fan-shaped resonance plates protruding from the diameter of the ring-shaped piezoelectric vibrator are symmetrically fixed to the side surface of the ring-shaped piezoelectric vibrator to form a stator, and one outer end of the resonance plate of the stator is linearly rod-shaped. An ultrasonic drive device, wherein a moving driven body is brought into pressure contact.