JPS6152168A - Twist and bent mode coupling type supersonic vibrator - Google Patents

Abstract

PURPOSE:To generate efficiently strong elliptical motion by deciding the relationship between the diameter and the thickness of a cylinder to parasitically bend and vibrate the cylindrical surface of a twist resonator. CONSTITUTION:A lead 2 is attached to the electrode of a piezoelectric thickness vibrator 1 made of ceramic, and the vibrator 1, a twist resonator 3 and a washer 4 are clamped by a cap bolt 5. The resonator 3 basically has a bottomed cylindrical shape so that the relationship between the diameter and the thickness of the cylinder is determined to parasitically bend and vibrate on the cylindrical surface. The height and the thickness of the resonator 3 are basic elements of twisting and bending mode coupling conditions, and when the diameter is varied, the way of coupling is altered, thereby arbitrarily performing various vibration modes at the vibrator.

Description

[Detailed Description of the Invention] [Field of Application and Purpose of the Invention] The present invention relates to the improvement of an ultrasonic vibrator, and a method that allows the vibrator to generate ultrasonic vibrations in an elliptical motion, and also facilitates the excitation. The purpose is to provide an ultrasonic transducer.

[Conventional technology]

The purpose of conventional ultrasonic transducers was to generate strong longitudinal vibrations, as typified by the Langevin type. on the other hand,
Recently, the development of technologies such as ultrasonic motors and ultrasonic parts feeders that utilize the powerful one-turn torque generated by ultrasonic scrap motion has been progressing. Although various methods for generating rotational torque have been proposed, the most excellent method is, for example, to generate elliptical motion on the surface of the motor's i1 element and rotate the rotor that is crimped thereto. Here, it is convenient to be able to directly use the vibration surface of the ultrasonic vibrator as a stator, but we have not been able to find a method to efficiently generate strong elliptical interlocking on the surface of one ultrasonic vibrator. It was not practical because it required a combination of multiple exciters, which produced only low-efficiency and weak vibrations.

[Means for solving problems]

This invention solves the above-mentioned drawbacks of the prior art.
In an ultrasonic transducer that excites torsional vibration in a cylindrical torsional resonator using a piezoelectric vibrator, the relationship between the diameter and wall thickness of the cylinder is selected so that the bending vibration is parasitic on the cylindrical surface. By doing so, the above objectives were achieved.

The inventor has already published an article titled ``Torsional mode ultrasonic transducer, pressure′; thickness FM exciter, longitudinal mode resonator.

We proposed a vibrator in which a torsion coupler and a torsion resonator are integrated. The principle is that a torsional resonator and a longitudinal vibration resonator are coupled by a torsional coupler, and it is necessary for both to resonate. However, it was subsequently discovered that torsional imaging could be oscillated simply by driving the torsional resonator with a piezoelectric thickness vibrator, and the present invention was created.

The main constituent element of the torsion/bending mode coupled ultrasonic transducer of the present invention is only a cylindrical torsional resonator, and there are no unnecessary restrictions such as a longitudinal vibrator or torsional resonator on the resonance conditions, so that the torsional mode can be efficiently twisted. - Flexural mode coupled vibration can be oscillated, making lifter design easier.

[Practical example]

FIGS. 1 and 2 are a front view and a side view of an example of an ultrasonic transducer. In the figure, 1 is a piezoelectric thickness vibrator made of ceramic, 2 is a lead wire attached to an electrode of the piezoelectric thickness vibrator 1, 3 is a torsion resonator, 4 is a washer, and 5 is a cap bolt for tightening these.

As shown in these figures, the torsional resonator 3 of the vibrator of the present invention is basically a cylindrical shape with a bottom, and has a basic shape or a slightly modified shape. The basic elements of the torsion/bending mode coupling condition are the height and wall thickness of the cylindrical torsional resonator 3, and the diameter of the cylinder couples the two. Since changing the diameter changes the way of coupling, it is possible to arbitrarily realize various vibration modes in the vibrator.

″The apparent shape of the actual vibrator also uses the helical torsion coupler 14 as shown in FIGS. This is a means for improving the efficiency of generating torsional vibration in the torsional resonator 13, and does not need to be used as shown in FIGS. 1 and 2.

In other words, the resonant frequency of torsional vibration generated in the vibrator is not affected by the torsional coupler. The M oscillator was found to be completely unnecessary, so it was excluded.

The torsion coupler 14 is attached to the bottom of the bottomed cylindrical torsion resonator 13,
When the joint is tightened with bolt 15, it is surprisingly bolt 15 that affects the excitation conditions of the resonance state the most.
is the length of A. The beam/bending mode coupled ultrasonic transducer of the present invention can excite vibrations in various modes depending on how it is designed, and has different functions, so it has a wide range of uses.

It is not easy to explain how the excited vibration mode changes depending on the design method and how the function of the resonator changes, so we selected 30 representative examples from the actual examples and summarized in the table below. It was shown to. These practical examples are the twists and turns of the present invention.
This figure shows how the vibration mode excited by the perturber and the transducer function change as the dimensions of each part of the bending mode coupled ultrasonic transducer change. First, in order to clarify the parts whose dimensions are to be changed, the dimension numbers of each part are shown in FIG. 4. In addition, in each practical example shown in the table,
The dimensions that were made the same throughout all the examples were the thickness of the torsional resonator, which had a thickness of 7, and the thickness of the piezoelectric vibrator, which had two thicknesses. If these changes were made, the result would be tedious and may cause confusion, and we could not find any essentially new information to be added, so we omitted the examples.

In the table, the dimensions to be changed are roughly divided into five groups: torsional resonators, torsional couplers, piezoelectric vibrators, washers, and bolts. Dimension changes for resonators, couplers, and piezoelectric vibrators are W F&
Each section has been subdivided into separate sections. An example of actual rotation is shown on a stone with the diameter of the resonator, and each group is distinguished by a double ruled line. The resonance frequency, vibration mode, and function of the vibration mode excited by the dimension change are shown in the right column.

The configuration of the torsion/bending mode coupled acoustic wave transducer of the present invention can be roughly divided into 3W1 types as shown in Figures 3, 4, and 5. The vibrators shown in FIG. 3 and FIG. 5 are made of the same parts and differ only in the way they are constructed. That is, the vibrator shown in FIG. 5 has a torsion coupler 14 inside a torsion resonator 13. It is a W55- that houses a piezoelectric resonator 11 made of ceramic and a washer 16, and is fixed from the inside with bolts 15, and is characterized by being more compact and convenient for utilizing the vibration of the outer surface of the bottom of the resonator. It is.

On the other hand, in the vibrator shown in Fig. 4, the cylinder of the torsional resonator 13 is not a blood line, but the side shape is trapezoidal. , model shown in Figure 5) or H# Hw (model shown in Figure 4).

In the table, examples A4 and 6 are type A shown in FIG. 3, and examples A4 and 7 are type C shown in FIG. Jiori Teiya 8 to 16 are H-Hw-7 heads, and are classified as A-type because they are A-type with a chamfered bottom rather than B-type. Examples A1.2, 3 and Example Graves 17-3
0 is type B shown in FIG. The model name is shown on the right side of the table.

Example of A-type vibrator & 6, Implementation height measurement of B-type vibrator 1
．． In Example No. 2 and C-type vibrator No. 7, when a disc-shaped rotor is pressed onto the bottom surface during excitation, the rotor rotates. In the embodiment IFx 1, the torsion resonator 13 as shown in FIG.
When a disk 6 with a small diameter is pressed onto the center of the disk, it rotates to the left. Next, if you change it to a disk with a larger diameter of 50 mm, it will no longer rotate. When the disk 7 was changed to a disk 7 with a larger diameter, clockwise rotation occurred as shown in Figure 7. In practical example 7fL2, a disk with a diameter of 50wn rotated clockwise with strong torque.

In the practical case 6, the bottom surface of the resonator 13 is flat as shown in FIG.
．． Left rotation occurred at a resonant frequency of 79 KHz.

Practical example A7, as shown in FIG. 9, has a cylindrical torsional resonator [3] with a chamfered bottom surface, and since the connector and the like are housed within the cylinder, it looks like a simple cylinder.

This was excited with the bottom facing up, and a disc rotor 8 with a diameter of 45 pieces was pressed onto the outer surface of the bottom. A bearing 9 is fitted in the center of the rotor 8, and a bolt 15 protruding from the center of the bottom surface of the vibrator is fitted and crimped onto the rotating shaft of the bearing 9. The rotor 8 had a resonant frequency of 29.93K H2 and performed a powerful clockwise rotation of several 1 Orpm. Next, Example 1
Looking at a 8, 769, it is similar to leprosy genus 6,
Although the diameter and length of the torsional resonator 13 were only slightly changed, no rotation occurred.

For height measurement 3 and height measurement 10, Figures 10 and 11
As shown in the figure, two rotors 72 and 73 are attached to the end face of a cylindrical torsion resonator 71 on a specific diameter of the torsion resonator 71.
When the two rotors 72 and 73 were brought into contact with each other with their rotational axes oriented in the diametrical direction, both rotors 72 and 73 rotated violently in the same direction. This is thought to be due to the occurrence of vibration in a mode in which the cylinder axis of the cylindrical torsional resonator 71 is bent. In Examples A4 and 5, unlike the other cases, strong resonance occurred at approximately 21.5 KH2 and approximately 30.5 KHz, respectively. occurred, but the disk placed on the bottom did not rotate and floated up. That is, when a disk was set and excited as shown in FIG. 8 in Practical Example 4 and as shown in FIG. 9 in Practical Example 5, it levitated without rotating as in the other cases. In this floating state, the disk can be freely rotated clockwise or counterclockwise. Once it is turned either clockwise or counterclockwise, it continues to rotate forever, and not only is it floating, but it seems to be in a state where there is no rotational friction.

Here, as shown in FIG. 12, a steel ball 8 with a diameter of 3 trrm is placed inside the cylinder of the resonator 83 of the practical example/764.
When I tried putting in a 7, the ball 87 moved around and bounced around like a drop of water on a heated 7-river.
In Examples 17 and A 21, in which the whole surface stood out quietly at a specific frequency, four pieces of shi-yu similar to those used in Examples j≦3 and A10 were prepared, and the 15th
As shown in the figure, a rotor 112 is attached to the first end face of the torsional resonator.
．． When IL3.114 and 115 were placed at four orthogonal diameter locations, all rotors rotated violently toward the center as indicated by the arrows.

In Examples &25, 27, and Black 29, as shown in FIG. 16, when a disk 122 having a trapezoidal cross section was placed on the end face of a cylindrical torsional resonator 121, the disk 122 rotated smoothly. On the other hand, Example 1≦13.18,22
, 23, 26, 28 and 30, the disc 122 did not turn as shown in Fig. 16, but it did not turn, but when a disc 124 with an inverted trapezoidal cross section was set as shown in Fig. 17, In all cases, it rotated violently, and the one that rotated most strongly was Example A30. The excitation wavenumbers are shown in the table. In these cases, the resonator 123 and the disk 12
4 is on the circumferential line of the inner corner of the resonator 123 (I
It is thought that the surface of the colander 123 moves in an elliptical manner along this line.

I thought that it would be difficult to receive large torque with line contact, so why not use Example 20? As shown in Figure A18, chamfering is performed along the inner corner of the cylindrical torsional resonator 125 as shown in Fig.
J#515 will change, so be careful, but Tomoka<'3
! : [Permutation] In the I620, when I put a disk 124 (one side of which has an inverted trapezoidal shape) in close contact with the surface +1V and the V and J parts, it rotated smoothly. When I increased the pressure, rattling and irregular vibrations occurred and smooth rotation could not be obtained.

Next, the recommended height measurements are 11, 12, 1.1, 15, 16
and! ≦19, when the disk is set as shown in Figure 17, it will rattle and vibrate irregularly, and sometimes it will turn clockwise, but then it will turn counterclockwise. These are the A-type resonators with a diameter of 60-1, an inner diameter of 46 mm, a wall thickness of 7 nan, and a bolt length of 4S to 50 mm, which produces exactly stable torsional bending waves. It is considered to be a situation where mining waves with opposite phases are in conflict.

The genus IO has a long circular surface, so the vibration must have changed to the bending vibration of the axis. By the way, in these oscillators, the first
With the disk 124 set as shown in Figure 9, press the knife 126 so as to cut into the external edge of the cylindrical torsional resonator 123.The disk 124 rotates to the right or to the left. In other words, when you want to rotate the knife to the left, put the knife 126 at a specific control center.
If you hit the knife 126, it will rotate to the left, and if you want to rotate it to the right, you can hit another specific location with the knife 126. i.e. knife 1
By selecting a pressing location, it is possible to rotate in any direction, whether clockwise or counterclockwise, and the strength of rotation is strong, with Example 16 being the strongest in both left and right rotations. The reason why the disk 124 is set on these vibrators causes rotation is thought to be because when the knife 126 is pressed, one of the traveling waves with opposite phases that are conflicting in the torsional resonator 123 disappears or attenuates. ,
It is thought that the disk 124 is rotated by the surviving traveling wave.

Example A24 is a typical example in which the rotor can be rotated by the outwardly facing part of the torsional resonator. As shown in FIGS. 20 and 21, when the axis of the rotor 142, 143, 144 is made parallel to the axis of the cylindrical torsional resonator 141 and the rotor surface contacts the outside 11 of the torsional resonator 141, the rotor 142 ~
144 rotates. The strength of rotation varies depending on the contact area, and the areas where no rotation occurs are weak, and the areas where rotation does not occur are on the line dividing the outer circumference into 6 equal parts, and the abdominal positions that rotate most strongly between these nodal lines are 60 degrees from each other. Exist at a distance. Rotor 1
Since the rotations 42 to 144 are opposite to each other on both sides of the nodal line, the ventral lines making the same rotation are 120 degrees apart from each other.

Now, when three rotors I42, 143 and 144 were crimped onto these abdominal lines as shown in FIG. 20, all three rotors 142 to 144 rotated violently in the same direction.

Next, when these rotors 142, 143, and 144 are moved to the locations 60 degrees apart shown by the dotted lines, the rotors 14
2”, 143°, and 144° turned violently in the opposite direction.

From this, a standing wave with a wave number n-3 in the torsion/bending mode is generated on the cylindrical surface of the cylindrical torsional resonator 141, and in the six abdomens separated by half a wavelength, the trajectory of the double line becomes an elliptical motion. It can be seen that there is a sonic vibration. This torsional resonator 1
4 has an outer diameter of 50 rrrm and an inner diameter of 36 mm, n-3
The wavelength of the standing wave is close to 37.7 M, which is obtained by dividing the inner circumference into three equal parts. Thickness 7#n.

When both ends of a beam of length j are fixed, the value of l that resonates at 26.4 KH7 is 38 mm, so the above 37.7 rran
There is weak agreement with . In a cylinder with an outer diameter of 60-1 and an inner diameter of 36 mm, there is a standing wave of n-4 at about 32 KHz as in Example &22, but the wavelength of 2πr/4 object 36# is
This almost coincides with the resonant wavelength 34 order at 32 KHz of the beam fixed at both ends.

Although not shown in the table shown in the practical example of the present invention, various modifications based on these may be considered. For example, FIG. 13 shows a ring-shaped projection 9 on the outer bottom of the torsional resonator 13 shown in FIG.
3 is provided, and if the rotor is placed on this ring 93 in the same manner as shown in FIG. Ta.

Further, FIG. 14 is a modification of the vibrator shown in FIG. 4 in which the bolt 15 is lengthened, but when a disk is set on this bolt 15, the disk rotates smoothly. These are only examples of the deformation m that utilizes the effect of the ultrasonic elliptical imaging occurring in the torsion/bending mode combined ultrasound imaging of the present invention, and other examples will be omitted.

〔Effect of the invention〕

As explained above, the present invention
In a cylindrical ultrasonic torsional resonator excited by a cylindrical waveform, the relationship between the diameter and wall thickness with respect to the length of the cylinder is selected such that bending vibration is parasitic on the cylindrical surface. Therefore, by changing the diameter and wall thickness conditions for the length of the cylindrical torsional resonator, the ultrasonic sensor can be used to control various surfaces of the resonator, such as side surfaces, end surfaces, inner surfaces, inner bottom surfaces, and outer bottom surfaces. Since it is possible to generate various modes of elliptical vibration on the tangent to a surface, it is ideally suited for use as a vibrator for ultrasonic motors, for example, and is highly effective in compensating for defective technologies that did not exist in the past.

[Brief explanation of drawings]

All of the figures are for explaining an ultrasonic transducer according to an embodiment of the present invention, and FIGS. 1 and 2 are a front view and a side view showing an example of an ultrasonic transducer, and FIG. Figure, 5th
Figures 13 and 14 are explanatory diagrams showing other examples of ultrasonic transducers, Figures 6, 7, 8, 9, and 10.
Figure, Figure 11, Figure 12, Figure 15, Figure 16, Figure 17
FIG. 18, FIG. 19, FIG. 20, and FIG. 21 are diagrams explaining the principles of each practical example of the present invention. 1.11.81...Piezoelectric thickness vibrator, 3,13
．． 71.83 horoscope 11.121, 123, 125.141
...Torsional resonator, 5, 15.85...
bolt. Figure 1 Figure 2 A1: Piezoelectricity/! Seven gripping movement pins 3: Resisting resonator 5: Bolt Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 70 Fig. 1/Fig. 12 Fig. 73 Figure 74 Figure 15 Figure 16 Figure 1? Figure 18 Figure 20 Three expansions of swords with threads (spontaneous) January 1980 ≠ Day

Claims (1)

[Claims] 1. In a cylindrical ultrasonic torsional resonator excited by a piezoelectric vibrator, the relationship between the diameter and wall thickness with respect to the length of the cylinder is selected so that bending vibration is parasitic on the cylindrical surface. An ultrasonic transducer that combines torsion and bending modes. 2. In the ultrasonic transducer according to claim 1, the relationship between the diameter and wall thickness of the torsional resonator cylinder with respect to the length is as follows:
A torsion/bending mode coupled ultrasonic transducer characterized by a cylindrical surface selected so that a bending traveling wave is generated. 3. In the ultrasonic transducer according to claim 1, the relationship between the diameter and wall thickness of the torsional resonator cylinder with respect to its length is as follows:
A torsion/bending mode coupled ultrasonic transducer characterized by having a cylindrical surface selected such that a symmetrical bending standing wave is generated along the circumference. 4. In the ultrasonic transducer according to claim 1, the relationship between the diameter and wall thickness of the torsional resonator cylinder with respect to its length is as follows:
A torsion/bending mode coupled ultrasonic transducer characterized in that at least one pair of locations on an axially symmetrical end face of a cylinder are selected so that elliptical vibrations in opposite directions relative to the axis occur. 5. Claims 1, 2, 3, and 4
2. An ultrasonic transducer coupled to torsional and bending modes, characterized in that the ultrasonic transducer according to any one of the above items uses a torsional coupler to increase vibration excitation efficiency.