JPS6038891A - Spiral-mode piezoelectric oscillator - Google Patents

Abstract

PURPOSE:To obtain the spiral oscillator in which an oscillation and a twisted oscillation are combined by a method wherein plural piezoelectric oscillation plates are overlapped in a manner the directions of a polarization of their thickness directions are not in parallel to that of the next one, and the elastic member whose compressive force works in the direction crossing obliquely the polarization direction and fastens those plates tightly. CONSTITUTION:The element 1 and 2 for Langevin type oscillator which are cylinders polarized in their thickness directions are sandwiched to be fixed by truncated-cone-shaped connectors 3 and 4. Then these are inserted between a wheel-shaped twist connects 5 and 6 which are arranged like two wheels of a car and the periphery of 6 and the periphery of 52 of 5 are fixed obliquely by impeller blades 7. The force which fastens firmly the whole oscillator by fitting the twist connector 5 in a screw of 52 is balanced with the tension working upon the impeller blades 7 so that a twisting force functions between the connectors 5 and 6. When an alternate signal of about 40kHz and 20V, for example, is applied between the electronic terminals 8 and 9 of the supersonic oscillator fastened to be set, a resonance phenomenon occurs at 42.7kHz and the end surfaces show an elliptical movement with the longitudinal direction as a longer axis.

Description

[Detailed Description of the Invention] An object of the present invention is to provide a piezoelectric pendulum in a twist mode in which a cylinder is twisted, and in a spiral mode in which the end face of the vibrator makes a thin circular motion with the normal to the surface as an axis. .

One type of piezoelectric motor uses circular motion as its driving force. As shown in Fig. 1, the rotor 15 and stator 14 are brought into close contact with each other under pressure, and the surface of the stator is made to move in a thin circle (indicated by a dotted line) with the main axis normal to the contact surface. If it is a clockwise rotation, move the rotor to the right and left &! If it is I, then it is a motor that moves it to the left. Since the driving force of this motor is determined by the speed and amplitude of circular motion (i), it is best to use a piezoelectric vibrator as a high-frequency resonator. Conventionally, the piezoelectric element that performs this pushing circular motion is As shown in Figure 1, the hλ principle is a oscillator that combines a vertical oscillator 1 and a left and right oscillator (travel mode oscillator) 2, in which 1 and 2 are excited with a phase different by 90 degrees.However, Since the vibrations are not coupled, the vibration direction of oscillators 1 and 2 is 9.
Because they are different by 0°, it is not possible to create a resonator that can perform strong thin circular motion without mutual interference.Moreover, it has the disadvantage that it must be driven using two signals with different phases. The lack of a sonic transducer was a deficiency in the prior art.

This invention solves the above-mentioned conventional technical deficiencies.
A plurality of disc-shaped piezoelectric vibrators that vibrate in the thickness direction in response to an electric signal applied in the thickness direction are stacked so that the directions of polarization are antiparallel to each other, and a compressive force is applied in a direction oblique to the polarization direction. By tightening with an elastic body on which a This objective was achieved by using a resonator in which the end face of the elastic body makes a thin circular motion with the polarization direction as the axis when excited. Embodiments of the present invention will be described below with reference to the drawings.

Embodiment] The second factor shows an embodiment of the present invention. Elements 1 and 2 for Langevin type resonators, which are polarized in the thickness direction of a PJ cylinder with an outer diameter of 30 mm, an inner diameter of 15 mm, and a thickness of 5 mm, are top-shaped. The connectors 3 and 4 are sandwiched and fixed, and this is inserted between the wheel-shaped torsion connectors 5 and 6 shown in FIG. 2(b). The torsion connectors 5 and 6 are arranged like the two wheels of a car, and the outer periphery of 6 and the outer periphery 52 of 5 are obliquely identified by the blades 7. Since 52 and 52 are cylindrical, the connector 3.4 made by sandwiching the ceramic 1.2 is set in the center of the cylinder. Here, by fitting the torsion connector 51 into the screw 52, the entire vibrator can be firmly tightened.

This tightening force is balanced with the tension acting on the blades 7, so if the blades are tightened too strongly, twisting force will act between the blades 5 and 6.

When a 20 volt alternating current signal of about 40 KJ],z was applied between the electronic terminals 8 and 9 of the mechanical ultrasonic transducer that had been tightened and set, a resonance phenomenon appeared at 42.7 K11z. When the end face of the vibrator was observed from the side with a microscope in this state, it was found that it was moving in a thin circular motion with the long axis being the longitudinal direction. The amplitude was 9 μnL in the long sleeve direction and 6 μm in the short axis direction.

In this way, we were able to obtain a spiral vibrator in which vertical vibration and torsional vibration were combined.

Example 2 FIG. 3 shows an example in which the spiral oscillator shown in FIG. 2 is made highly efficient. The outline of the structure is as follows: 10 ceramic discs are stacked at a pressure 1 of 30 trtv, φ/12 to φ , is a Langevin type vibrator using ordinary duralumin connectors 3 and 4 and tightened with bolts 8. The difference from a normal Langevin type vibrator is that the laminated piezoelectric rings 1 and 20 are sandwiched with twisted connectors 5, and when the bolts are tightened, the connectors 3 and 2
A twist occurs between the two. The screw connector 5 is a metal in the shape of an impeller, and the blades are metal plates with a thickness of 2 mm, and are arranged 4 at an angle of several degrees with respect to the bolt tightening direction. When an AC signal of 48.3 KJ (z, 5V) was applied to the electric equalizers 9 and 10, the end face of the connector 6 was aligned with the long axis 15.
It was confirmed that it operated as a spiral oscillator that performed a circular motion with a short axis of 10 μm. Vibration speed approximately 700TI
V'81 city power is approximately 5 W, and therefore a highly efficient and powerful spiral ultrasonic transducer can be provided. 11.
12 is a ball bearing.

Embodiment 3 In Embodiment 2, the two connectors generate torsional vibrations in opposite directions, but when one connector is fixed in order to extract mechanical output from this vibration, it also affects the other. The fixing method is difficult. Here, a π structure for obtaining a large output by fixing a vibrator to an official seal is disclosed.

Fig. 4 shows its front view. Roughly speaking, the element shown in Figure 3 is divided into two parts from the center plane, and the left and right sides are symmetrical.
The whole can be supported and fixed by the fixing plate 13 having a symmetrical surface; (4.1) The angle of inclination of the blades of the connector is symmetrical. (2) Since the connectors 3 and 4 deform in the same direction relative to the fixing plate, they can be directly bolted and fixed, and there is no need for a latch mechanism using ball bearings or the like as in the case of FIG. 3.

Except for the above three points, the configuration may be the same as in the second embodiment.

The spiral mode piezoelectric vibrator assembled in this way is caused by a high frequency signal of about 40 KHz applied to the lead wire 9.10, and as a result, the couplers 3.4 align against the fixed plate 13, causing torsional vibration. , a strong spiral mode vibration could be excited. This spiral mode pressure 1E vibrator can be firmly held by a fixed plate, so strong mechanical output can be easily extracted. As explained above, multiple piezoelectric diaphragms are stacked so that the direction of polarization in the thickness direction is antiparallel to each other, and then tightened with an elastic body that applies compressive force in a direction diagonal to the direction of polarization. In addition, since the structure is configured so that the elastic force generated in the polarization direction when electrically excited and the twisting force generated around the polarization axis combine to resonate, the end face of the vibrator is located within the column with the polarization direction as the axis. The great effect is that we were able to provide an element for a new technology that was lacking in conventional high-intensity ultrasonic generation technology, which is a spiral mode piezoelectric vibrator that is characterized by motion. Furthermore, since this element is a two-mode coupling element, it has the feature of being highly efficient and capable of generating a large torsion torque.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the operating principle of a pressure 1TL motor that uses in-column motion as driving force. (a) is an explanatory diagram of the principle; (b) is a front view of a conventional piezoelectric element for generating partial motion; FIG. 2 is a front view (,) and side view showing an embodiment of the present invention; Front view showing another embodiment of the invention FIG. 4 is a front view showing another embodiment of the invention. 1.2...Piezoelectric diaphragm 3.4...Coupler 5.6.
7... Twisting blade 8... Bolt nut (a) No. [a] (b) Figure 8 5 M4 diagram

Claims (1)

[Claims] (1) An elastic body in which a plurality of piezoelectric diaphragms are stacked so that the directions of polarization in the thickness direction are antiparallel to each other, and a compressive force is applied in a direction oblique to the direction of polarization. By tightening, the elastic force generated in the polarization direction when electrically excited and the P1 deer generated in the rotation of the polarization axis combine and resonate, resulting in the end face of the vibrator forming a thin circle with the polarization direction as its axis. A spiral mode piezoelectric vibrator that is characterized by motion. (2. In the spiral mode piezoelectric vibrator described in claim 1, the elastic body causes torsional deformation around the axis when expanded and contracted in the axial direction, and this is caused by a plurality of piezoelectric vibrators. A spiral mode piezoelectric vibrator characterized in that it is bolted in a sandwiched state with a vibration coupler. (3) In the spiral mode piezoelectric vibrator according to claim 2, a torsional deformation elastic coupling is provided. By making a pair of a ceramic resonator, a ceramic resonator, and a vibration coupler and coating them with a thin acid in a planar symmetrical shape on a central support plate, both end faces of the vibration coupler are twisted in the same direction with respect to the support plate. A spiral mode piezoelectric vibrator that is characterized by