JP3235907B2 - Ultrasonic drive - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art The applicant of the present invention has formed electrodes on both sides of a ring-shaped vibrator or a disk-shaped vibrator, provided a groove at the center of these electrodes, divided each electrode into two, and formed an angle of the groove. The ultrasonic drive device that generates a traveling wave on the side and both sides of the ring-shaped vibrator or the disk-shaped vibrator by applying an AC voltage to one electrode of each of the two divided two-sided electrodes. Proposed (Japanese Patent Laid-Open No.
Reference).

[0003]

However, the efficiency of this ultrasonic driving device is as low as about 5%.

[0004]

According to the present invention, there is provided a ring-shaped piezoelectric vibrator in which electrodes are provided on both sides and an AC voltage is applied to the electrodes to generate a traveling wave. A stator provided with a plurality of fan-shaped or rectangular resonance plates integrally protruding from the diameter of the ring-shaped piezoelectric vibrator and having an inner end bonded with a ring-shaped synthetic resin, and a ring-shaped stator; A rotating shaft is supported by a case in which the center hole of the piezoelectric vibrator is fixed to the projecting portion, and a bearing provided in the center hole of the case, and a slider at the end of a cylinder supported by the rotating shaft is the resonance plate. And a rotor pressed against the side surface by a leaf spring.The resonance plate may be coated with an insulating film, or the resonance plate may be provided with a radial cut in a disk and left by the cut. A fan-shaped resonance plate may be used. The ring-shaped piezoelectric vibrator which is provided with an electrode, and which is adapted to generate a traveling wave by applying an AC voltage to the electrode, is fixed to both sides in a circular shape, protrudes from the diameter of the ring-shaped piezoelectric vibrator, and has an inner end. Provided with a plurality of fan-shaped or rectangular resonance plates integrally formed by bonding together with a ring-shaped synthetic resin, and a case in which the center hole of the ring-shaped piezoelectric vibrator of the stator is fixed to the protruding portion. A protrusion is inserted between the resonance plates, and a ring-shaped elastic member is inserted into a groove formed in a portion opposed to the protrusion, and the vicinity of one end of each of the plurality of sliders pressed radially is near each end. And the other end is fixed to a rotating shaft, and the rotating shaft is composed of a rotor attached to the case.The ring-shaped elastic member may be a rubber band, and the ring elastic member is A ring-shaped spring may be used. The plate may be coated with an insulating film, or electrodes may be provided on both surfaces, and the ring may be fixed to one surface of a ring-shaped piezoelectric vibrator in which an AC voltage is applied to the electrodes to generate a traveling wave. A stator provided with a plurality of rectangular resonance plates protruding symmetrically from the diameter of the piezoelectric vibrator, a case to which a ring-shaped piezoelectric vibrator of the stator is fixed, and the case mounted to the stator and fixed to the stator. A rod-shaped linearly-moving driven body pressed against one outer end of the resonance plate by a spring mounted on the case may be provided, and the resonance plate may be coated with an insulating film.

[0005]

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

The traveling wave is transmitted to a fan-shaped resonance plate fixed to the side surface of the piezoelectric vibrator. Since the resonance plate protrudes beyond the diameter of the ring-shaped piezoelectric vibrator, each fan-shaped resonance plate is protruded. The plate becomes a traveling wave resonance member, and the amplitude is enlarged.

Therefore, when the rotor is pressed against the resonance plate, the driving body is driven by the amplified traveling wave, and the efficiency is increased 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. FIG. 2 is a side view of FIG.
A large number of fan-shaped resonance plates 2 are adhered to the side surface of the resonance plate 2 in a ring shape with a ring-shaped synthetic resin 3 so that the inner end 2a is substantially aligned with the hole 1a of the piezoelectric vibrator 1, and the outer end of the resonance plate 2 is formed. Is 2
b is formed to be substantially circular, protruding from the diameter of the piezoelectric vibrator 1, and the stator 4 is formed.

FIG. 3 is a plan view of a stator of an ultrasonic driving apparatus according to another embodiment of the present invention, and FIG. 4 is a side view of FIG. A large number of resonance plates 2 are aligned such that their inner ends 2a substantially coincide with the holes 1a of the piezoelectric vibrator 1, and a large number of fan-shaped resonance plates 2 are bonded with a synthetic resin 3a. 2b is formed in a substantially circular shape by projecting from the diameter of the piezoelectric vibrator 1, and
Is formed.

FIG. 5 is a structural view of an ultrasonic drive device using these stators 4, and FIG. 6 is a plan view of a rotor of the ultrasonic drive device of FIG. 4 is formed of a sliding member, a rotating shaft 7 is fixed to the center of the cylindrical portion 6 of the rotor 8, and a 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 a thrust bearing 11 is attached to the rotating shaft 7.
Is mounted so that the slider 6 a of the cylindrical portion 6 of the rotor 8 is pressed against the resonance plate 2 of the stator 4 by a leaf spring 12 provided between the thrust bearing 11 and the rotor 8.

In the ultrasonic driving apparatus according to the present 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 expanded by the expanded traveling wave. It rotates efficiently and its rotation torque is large, so that it is possible to efficiently drive another driving body connected to the rotating shaft 7.

FIG. 7 is a sectional view of an ultrasonic driving apparatus according to still another embodiment of the present invention, wherein 1 is an ultrasonic vibrator, 2 is a resonance plate,
5 is a case, 6 is a cylindrical part, 7 is a rotating shaft, 8 is a rotor,
Reference numerals 9 and 10 denote bearings, and their configurations are the same as those in the above embodiment. Therefore, in this embodiment, a coil spring 112 is used instead of the leaf spring 12 in order to press the rotor 8 against the resonance plate 2. I'm using

In this embodiment constructed as described above, the rotor 8 is efficiently rotated by the traveling wave expanded by the resonance plate 2 as in the above embodiment, the torque is large, and the rotor 8 is connected to the rotating shaft 7. Can be efficiently driven.

Further, in the ultrasonic driving apparatus of this embodiment, the thickness of the ring-shaped piezoelectric vibrator 1 is 1 mm to 1.5 mm, and the thickness of the resonance plate 2 is also 1 mm to 2 mm. Therefore, such an ultrasonic drive device can be stopped immediately when the power supply is cut off. It can be used to rotate a volume or used for other control equipment.

In the above embodiment, the gap between the two resonance plates is made to match the electrode dividing line of the piezoelectric vibrator 1, and a large number of fan-shaped resonance plates 2 are placed above the electrodes of the piezoelectric vibrator 1. Even if it is directly bonded to the substrate, it is insulated by the ring-shaped synthetic resin 3 and the synthetic resin 3a for bonding. However, a thin insulating plate such as anodized aluminum is provided on the electrodes, or a thin insulating plate is provided. Can be used to insulate the fan-shaped resonance plate 2, and furthermore, the resonance plate can be integrally molded by this method.

In the above-described embodiment, the resonance plate 2 is formed in a fan shape. However, rectangular resonance plates may be arranged in a circle, and the outer periphery may be made circular.

FIG. 8 is a plan view of an ultrasonic driving apparatus according to another embodiment of the present invention, and FIG. 9 is a side view of FIG. 8, wherein a circular fan-shaped resonance plate 2 is provided on both surfaces of a ring-shaped piezoelectric vibrator 1. Glued,
The inner end is fixed with the synthetic resin 3 to form a stator 13, and the stator 13 is fixed by inserting the protruding portion 5 a of the case 5 into the hole 1 a of the piezoelectric vibrator 1.

Also, a number of sliders 14 (eight in the figure) provided with protrusions 14a so as to be sandwiched between the resonance plates 2 on both surfaces of the piezoelectric vibrator 1 are formed in grooves formed in opposing portions of the protrusions 14a. 14
b, the rubber band 15 is inserted into the stator 1.
3 is pressed against the resonance plate 2.

Further, two protrusions 16 are fixed to the side surface of the slider 14 at intervals, and one end of each of a plurality of supports 17 is radially supported between the protrusions 16. The other end of the body 17 is fixed to the rotating shaft 7 to form a rotor 18. The rotating shaft 7 of the rotor 18 is supported by bearings 9 and 10 provided on the case 5.

In the ultrasonic driving apparatus according to the present embodiment, the rotor 18 is rotated with a higher torque by the expanded traveling wave of the resonance plates 2 on both surfaces of the piezoelectric vibrator 1 and the efficiency is high. There are advantages.

The slider 14 may be pressed against the resonance plate 2 of the stator 13 by a ring-shaped spring instead of the rubber band 15.

FIG. 10 is a plan view of an ultrasonic driving apparatus according to another embodiment of the present invention, in which a cover is opened. FIG. 11 is a side sectional view of FIG. Board 1
9 is bonded symmetrically to form a stator 20, and the piezoelectric vibrator 1 of the stator 20 is fixed to the case 5 by inserting the protruding portion 5a of the case 5 into the hole 1a. A portion of the resonance plate 19 protruding from the piezoelectric vibrator 1 is inserted into a groove 21 a of a driving body 21 which moves linearly, and the driving body 21 is fixed to the stator 2 by springs 22 and 23.
0 is pressed against the resonance plate 19.

In the ultrasonic driving apparatus according to the present embodiment, the traveling wave of the piezoelectric vibrator 1 is expanded by the rectangular resonance plate 19 and the driving body 21 is driven.
Can be driven with high torque.

In the above embodiment, the stator is formed by integrating the separated resonance plates 2, but as shown in FIG. 11, cuts 25 are formed radially from the outer end 24 a toward the inner end 24 b. A stator can be similarly formed by bonding the resonance plate 24 provided and the fan-shaped resonance plate 26 left between the cuts 25 at the inner end 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. Therefore, the resonance plate 24 is coated with an insulating film.

[0026]

As described above, in the ultrasonic driving apparatus according to 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 the power is expanded, the efficiency is improved from 5% to 20%, and when the power supply is stopped, the power is immediately stopped, so that the power can be used as it is for positioning control and rotation of a volume and the like. There is an advantage.

[Brief description of the drawings]

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

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

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

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

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

FIG. 6 is a plan view of the rotor of FIG. 5;

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

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

FIG. 9 is a side sectional view of the ultrasonic driving device of FIG. 7;

FIG. 10 is a plan view of an ultrasonic driving apparatus according to another embodiment of the present invention with a cover opened.

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

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ring-shaped piezoelectric vibrator 2 Resonance plate 3, 3a Synthetic resin 4, 13 Stator 5 Case 6 Cylindrical part 6a, 14 Slider 7 Rotating shaft 8 Rotor 9, 10 Bearing 11 Thrust bearing 12 Spring 15 Ring rubber 16 Projection 17 Support Reference Signs 18 rotor 19 resonance plate 20 stator 21 driver 22, 23 spring 24 resonance plate

Claims (9)

(57) [Claims] 1. A ring-shaped piezoelectric vibrator which is provided with electrodes on both sides thereof, and which is applied with an AC voltage to generate a traveling wave by applying an AC voltage to the electrodes, is fixed in a circular shape on one surface thereof and has a diameter larger than that of the ring-shaped piezoelectric vibrator. A stator provided with a plurality of fan-shaped or rectangular resonance plates integrally formed by projecting and bonding the inner ends thereof with a ring-shaped synthetic resin, and projecting through a center hole of a ring-shaped piezoelectric vibrator of the stator. A rotating shaft is supported by a case fixed to the portion and a bearing provided in a center hole of the case, and a slider at an end of a cylinder supported by the rotating shaft is pressed against a side surface of the resonance plate by a leaf spring. An ultrasonic drive device comprising: a rotor. 2. The ultrasonic driving device according to claim 1, wherein said resonance plate is coated with an insulating film. 3. The ultrasonic driving apparatus according to claim 1, wherein said resonance plate is provided with a radial cut in a disk, and comprises a fan-shaped resonance plate left by said cut. 4. A ring-shaped piezoelectric vibrator which is provided with electrodes on both sides thereof and which is adapted to generate a traveling wave by applying an AC voltage to the electrodes and which is fixed in a circular shape on both sides to a diameter of the ring-shaped piezoelectric vibrator. A stator provided with a plurality of fan-shaped or rectangular resonance plates integrally formed by projecting and bonding an inner end portion thereof with a ring-shaped synthetic resin, and a center hole of a ring-shaped piezoelectric vibrator of the stator. A projecting portion is inserted between the case fixed to the projecting portion and the resonance plate, and a ring-shaped elastic member is inserted into a groove formed in an opposing portion of the projecting portion. An ultrasonic drive device comprising: a radially fixed end near one end; a second end fixed to a rotating shaft; and a rotating shaft attached to the case. 5. The ultrasonic driving device according to claim 4, wherein said ring-shaped elastic member is a rubber band. 6. The ultrasonic driving device according to claim 4, wherein said ring elastic member is a ring-shaped spring. 7. The ultrasonic drive device according to claim 4, wherein said resonance plate is coated with an insulating film. 8. An electrode is provided on both surfaces, and is fixed to one surface of a ring-shaped piezoelectric vibrator that generates an advancing wave by applying an AC voltage to the electrode and is symmetrical with respect to the diameter of the ring-shaped piezoelectric vibrator. A stator provided with a plurality of protruding rectangular resonance plates, a case to which a ring-shaped piezoelectric vibrator of the stator is fixed, and one outer end of the resonance plate mounted to the case and fixed to the stator; An ultrasonic drive device comprising: a driven body that moves linearly in a rod shape pressed by a spring mounted on a case. 9. The ultrasonic driving device according to claim 8, wherein said resonance plate is coated with an insulating film.