JPS63129871A - Vibrating-reed motor - Google Patents

Abstract

PURPOSE:To improve general applicability, by a method wherein a plurality of electromechanical conversion elements, for supporting ultrasonic vibration, is attached to a vibration reed while vibrations, having different directions respectively, are excited in these elements. CONSTITUTION:A cantilever type vibration reed 4 is projected from an ultrasonic vibration generation member 2, constituting a vibrating-reed motor, and a vertically vibrating member 8, constituted of two sheets of piezo-electric elements 6 polarized in the direction of the thickness thereof, is attached to the lower surface of a supporting end. A horizontally vibrating member 12, constituted of two sheets of piezo-electric elements 10, polarized in the direction of the thickness thereof in the same manner, is attached to the side surface of the supporting end. When a voltage in the direction of the thickness thereof is impressed on respective piezo-electric elements 6 of the vertically vibrating member 8 and an AC electric signal is inputted into the electric pole 6a, the vertical vibration of a vibration reed 4 is excited in accordance with the frequency and the amplitude of the signal. On the other hand, horizontal vibration is excited in the horizontally vibrating member 12 in the same manner. As a result, two vibrations are synthesized to excite vibration in the vibration reed 4 whereby a rotor may be driven by the vibration of elliptic track, which is realized in the vibration reed 4.

Description

[Detailed Description of the Invention] Purpose of the Invention [Industrial Field of Application] The present invention provides a vibrating piece type motor that can move a movable element in contact with a vibrating piece by exciting a substantially circular motion in the vibrating piece. Regarding.

[Prior Art] Conventionally, vibration from a single electromechanical transducer is transmitted to the vibrating element of a vibrating element type motor, and the ultrasonic vibration generated by this electromechanical transducer and the free vibration of the vibrating element are combined. 2
Elliptical motion is excited as a result of the vibrations of the seeds. If the movable element is brought into contact with this elliptically moving vibrating piece with a predetermined pressure,
The movable element receives a moving force in the same direction as the elliptical movement of the vibrating element, and is capable of linear movement, rotational movement, etc.

[Problems to be Solved by the Invention] However, in the above-mentioned photographing single wall motor, free vibration of the vibrating element itself is essential in order to obtain elliptical motion of the vibrating element.

For this reason, the direction and speed of the elliptical motion are uniformly determined depending on the shape of the vibrating piece, and therefore, with conventional vibrating piece type motors, the moving direction and speed of the movable element cannot be set to the desired specifications. , its application field was limited.

The present invention was made to solve the above problems, and it is possible to set the so-called motor characteristics such as the moving direction and moving speed of the mover to desired specifications, and it has excellent versatility and can be used in a wide range of applications. The purpose is to provide a vibrating piece type motor.

Structure of the Invention [Means for Solving the Problems] In order to solve the above problems, according to the present invention, ultrasonic vibrations are generated by applying an alternating current electric signal generated from an electric signal generating means. It has an electromechanical transducer, a vibrating piece to which strength is transmitted from the electromechanical transducing element, and a movable element that abuts the vibrating element with a predetermined pressure, the movable element that abuts the vibrating element. In a vibrating piece type motor that is moved by vibrations excited in a vibrating piece, a plurality of the electromechanical transducers are installed so as to excite ultrasonic imaging in different directions to the vibrating piece, and the electric signal generating means is , characterized in that an AC electrical signal having at least a predetermined amplitude, phase, or frequency is applied to the plurality of electromechanical transducers.

[Function] In the vibrating piece type motor of the invention, a plurality of electromechanical transducers that support the ultrasonic vibration vJ are attached to the vibrating piece, and each of these excites vibrations in different directions in the vibrating piece. Then, an AC electric signal of a predetermined amplitude, phase, or frequency is applied to the plurality of electromechanical transducers by an electric signal generating means, thereby changing the amplitude and direction of the ultrasonic vibration excited in the vibrating piece. etc. can all be set to desired specifications.

[Examples] Hereinafter, in order to explain the present invention more specifically, examples will be given and explained.

FIG. 1 is an enlarged perspective view of an ultrasonic vibration generating member 2 constituting the vibrating piece type motor of the embodiment. As shown in the figure, a cantilever-shaped vibrating piece 4 is protruded from the ultrasonic vibration generating member 2, and two piezoelectric elements 6 polarized in the thickness direction are mounted on the lower surface of the supporting end of the vibrating piece 4. A vertical vibration member 8 composed of m-shaped members is installed, and a horizontal vibration member 12 made of two stacked piezoelectric elements 10 similarly polarized in the thickness direction is installed on the side surface of the support end. Therefore, if an alternating current electrical signal is input to the electrode 6a of each piezoelectric element 6 of the vertical vibration member 8 in order to apply a voltage in the thickness direction, the rotating piece 4 will change depending on the frequency and amplitude of the alternating electrical signal. vertical vibrations are excited. That is, the amplitude of vibration in the vertical direction of the drawing is controlled in proportion to the amplitude of the AC electric signal, and vibrations with a frequency matching the frequency of the AC electric signal are obtained. It is clear that the horizontal vibration member 12 has the same effect as described above, and if an arbitrary alternating current electric signal in the thickness direction is applied to the piezoelectric element 10 through the electrode 10a, the vibration element 4 changes depending on the frequency and amplitude of the electric signal. Horizontal vibrations in the front and back directions of the drawing are excited.

The combination of the vibrations in the above two directions becomes the vibration excited in the vibrating element 4, for example, the vertical vibration member 8.
AC electric signal 90' applied to the horizontal vibration member 12
If the vibrations have the same frequency and the same amplitude with a phase difference of , the tip of the vibrating element 4 performs a circular motion. In addition, if only the amplitude of the AC electric signal applied to the vertical vibration member 8 is increased in this state, the tip of the vibrating element 4 becomes an ellipse with the major axis in the vertical direction and the minor axis in the horizontal direction, as shown in FIG. Orbital vibrations appear.

In other words, the various vibrations appearing at the tip of the vibrating element 4 are a combination of vibrations in different directions independently excited by the vertical vibration member 8 and the horizontal vibration member 12, and are applied to these members. By controlling the phase difference, frequency, and amplitude of the AC electric signal, it is possible to obtain desired vibrations.

Figure 2 shows two ultrasonic vibration generating members configured as described above.
FIG. 2 is an explanatory cross-sectional view of an embodiment in which a vibrating piece type motor is constructed by using two vibrating pieces. The two ultrasonic vibration generating members 2A and 2B are mounted on a circular chassis 2 with their respective vibrating pieces 4A and 4B facing each other.
It is fixed to the peripheral wall of the chassis 20 using bolts 22A and 22B so as to match the diameter of the chassis 20. Also, Si1
! - A circular rotor 26 is rotatably attached to the central axis 24 of the housing 20 via a bearing 28, and is pressed by a spring 30 so as to come into contact with the top surface of the tip of the vibrating pieces 4A, 4B with a predetermined pressure. ing.

In the vibrating piece type motor having the above configuration, the tips of the vibrating pieces 4A and 4B of the ultrasonic vibration generating members 2A and 2B vibrate in an elliptical orbit with the major axis in the vertical direction in the same phase and with the same period as described above. If a predetermined alternating current electric signal is applied to a total of four vibrating members so as to occur in the rotor 26
It is clear that rotates in the same direction as the elliptical motion described above.

Furthermore, in the vibrating piece type motor of this embodiment, since the vibrations generated by the two ultrasonic vibration generating members 2A and 2B can be freely controlled as described above, the rotational movement of the rotor 26 can also be controlled. It becomes possible. That is, if the frequency of the AC electric signal applied to each photographing member is simply increased in order to shorten the period of the elliptical motion of the photographing pieces 4A and 4B from the rotational state of the rotor 26 described above, the rotor 26 will be more stable than before. Rotates at high speed. Similarly, if only the amplitude of the AC electric signal is controlled, the contact force between the vibrating pieces 4A, 4B and the rotor 26 becomes variable, so only the torque of the rotor 26 can be adjusted.

As described above, in the vibrating piece type motor of this embodiment, the so-called motor characteristics such as the rotational speed and the generated torque can be freely and independently adjusted, making it an excellent vibrating piece type motor with extremely high versatility.

3 and 4 are explanatory diagrams of the groove bottom of a vibrating piece type motor according to another embodiment, and FIG. 3 is an exploded perspective view thereof, and FIG.
The figure shows its longitudinal cross-section.

As shown in the figure, the vibrating piece type motor of this embodiment has a stator 4
Cantilever-shaped vibrating pieces 42 and 44 are formed protruding from 0 in both the left and right directions, and on the side and bottom surfaces of the central part of each vibrating piece 42 and 44, vibrations in the long axis direction of the imaging piece are provided in accordance with AC electric signals. Piezoelectric elements 42a, 42b and 44 that perform expansion and contraction movements
a and 44b are installed. Therefore, the vibrating piece 42
．． Due to the expansion and contraction movement of the piezoelectric elements 42a and 44a attached to the side surfaces of the vibrating element 42, 44, bending vibration in the front and back directions of the drawing is excited with both ends of the imaging element as nodes and the center thereof as the maximum displacement position. be done. Similarly, a piezoelectric element 42b is attached to the bottom surface of the vibrating piece 42,44.

- Due to the expansion and contraction movement of the vibrating pieces 14b, the vibrating pieces 42 and 44 are excited to bend in the vertical direction in the drawing with both ends as nodes and the center as the position of maximum displacement.

In other words, the vibrations excited in the vibrating pieces 42 and 44 are
This is a composite of seed photography, with piezoelectric elements 42 on the side and bottom surfaces.
By applying an AC electric signal with a predetermined phase, frequency, and amplitude to a, 42b and 44a, 44b, the vibrating element 42.4
The bending vibration of No. 4 can be controlled in any way. Therefore,
A rotor 50 is placed on the upper surface of this vibrating piece 42, 44, and a bolt 52 screwed onto the stator 40 and a spring 54 loosely fitted to the bolt 52 are used to connect the rotor 50 and the vibrating piece 4.
2.44 with a predetermined pressure, the vibrating piece 42
．． A vibrating piece type motor can be constructed in which rotational force is transmitted to the rotor 50 by desired vibrations generated in the rotor 44. In addition, even with the vibrating piece type motor of this embodiment, the vibration state of the vibrating pieces 42 and 44 can be freely controlled as in the above-mentioned embodiment, so the motor characteristics can be adjusted, making it highly versatile. It becomes a photographing single type motor.

In the above two embodiments, all piezoelectric elements were used as electromechanical transducers, but other electromechanical transducers such as electrostrictive elements or LA electrostrictive elements may be used instead. It is clear that the same action and effect can be achieved. Furthermore, the present invention is not limited to the above embodiment in which two electromechanical transducers are attached to one vibrating element so that the directions of their excited vibrations are orthogonal; The present invention may be embodied in various ways without departing from the gist of the present invention, such as by attaching the elements to one imaging piece.

The effects of the invention will be described in detail with reference to examples.As shown in JL7, the vibrating piece type motor of the present invention can freely control the imaging excited in the vibrating piece by a plurality of electromechanical transducers, and the so-called motor characteristics are independent. It can be adjusted to Therefore, it is an excellent vibrating piece type motor that is extremely versatile and has a wide range of applications.

[Brief explanation of the drawing]

Fig. 1 is an enlarged perspective view of an ultrasonic vibration generating member constituting the vibrating piece type motor of the example, and Fig. 2 is a cross-sectional view of a photographing piece type motor using the same ultrasonic vibration generating member. The figure shows an exploded perspective view of a moving piece type motor according to another embodiment, and FIG. 4 shows a longitudinal sectional view of the embodiment. 4.4A, 4B, 42, 44... system moving piece 6.10.4
2a, 42b, 44a, 44b...Piezoelectric element 26.50...Rotor

Claims (1)

[Scope of Claims] An electromechanical transducer that generates ultrasonic vibrations when an alternating current electrical signal generated by an electrical signal generating means is applied, and a vibrating element that transmits the vibrations from the electromechanical transducer. a movable element that comes into contact with the vibrating piece at a predetermined pressure;
In a vibrating piece type motor that moves a movable element in contact with the vibrating element by vibrations excited by the movable element, the electromechanical transducer includes a plurality of electromechanical transducers that excite ultrasonic vibrations in different directions to the vibrating element. A vibrating piece type motor, wherein the electric signal means applies an AC electric signal having at least a predetermined amplitude, phase, or frequency to the plurality of electromechanical transducers.