JPH0828985B2 - Ultrasonic motor rotor / mover - Google Patents

Description

The present invention relates to a rotor / mover of an ultrasonic motor that utilizes ultrasonic vibration. More specifically, the present invention relates to an improved rotor or mover capable of improving motor efficiency and increasing motor output in an ultrasonic motor that utilizes bending vibration (ultrasonic vibration) of a piezoelectric body. It is a thing.

[Conventional technology and its problems]

A new driving method utilizing the strong vibration energy of ultrasonic waves and a motor device based on this method have been proposed by the inventor of the present invention (Japanese Patent Publication No. 1-17353), and as the practical application thereof progresses, ultrasonic waves The excellent characteristics of motors have been widely noticed, and their application to various technical fields has been actively studied.

In this ultrasonic motor, a stator as an ultrasonic vibrator is composed of a plurality of piezoelectric bodies (electrostrictive elements) and an elastic body such as metal, and the piezoelectric elements (electrostrictive elements) arranged in parallel are temporally phased. Applying different high-frequency voltage to generate a vibration wave on the predetermined surface of this stator, and drive the rotor or mover that is in pressure contact with the stator surface in the predetermined direction by the surface vibration wave. Is the principle feature.

Since the inventor of the present invention has been making various improvements and improvements in the process of its practical use since proposing an ultrasonic motor composed of this basic principle and configuration, in this study, the efficiency as a motor was improved. Improving was one of the challenges. It was to improve the motor efficiency to a greater extent and to achieve higher output as a motor.

The present invention has been made for the purpose of solving the above problems.

[Means for solving the problem]

The present invention solves the above problems by contacting a stator in a rotor / mover that pressurizes and contacts the surface of a stator fixed to a piezoelectric body, which generates a vibration wave in which transverse and longitudinal waves are combined. The rotor / mover is composed of a flexible slide body (slider) made of a thin elastic body having a high friction coefficient and a flexible support body fixed to the slide body. There is provided a rotor / mover of an ultrasonic motor, characterized in that the whole is elastically deformed.

That is, in the case of the ultrasonic motors proposed so far, the energy loss due to the elastic deformation of the sliding member made of a rubber-like elastic body having a high friction coefficient brought into pressure contact with the ultrasonically vibrating stator is large, Although there was a limitation in improving the motor efficiency, the present invention has found that it is possible to make such a sliding body flexible and make it as thin as possible to reduce energy loss due to elastic deformation. It was made based on.

Further, conventionally, as the sliding body which constitutes the rotor / moving element, as the supporting body, one having rigidity that is not deformed even when the vibration pressure from the stator is received is used.
In the case of the present invention, as described above, since the sliding body is made as thin as possible, the supporting body is also made flexible, and the rotor / mover composed of the sliding body and the supporting body is elastically deformable as a whole. It was found that imparting the property is effective in improving the motor efficiency and increasing the output of the motor, and specifically completed the present invention.

Hereinafter, the configuration and operational effects of the present invention will be described in more detail with reference to the drawings.

First, FIG. 1 illustrates the operation of a conventional motor device in principle. As shown in FIG. 1, also in the case of the conventional device, an oscillating wave (bending wave) in which a transverse wave and a longitudinal wave are combined is formed on the surface of the stator 1 and propagates. Each vertex of the surface 1a of the stator 1 is elliptically oscillated as is generally known, and the oscillating wave is moving at the speed of sound U.

In addition, the sliding body 3 which constitutes the rotor / mover 2 is
While being in contact with the vibration wave formed on the surface of the stator 1, it is driven in the direction of arrow N by the frictional force. At this time, the frictional driving force is generated by the high friction coefficient of the sliding body 3 and the large elastic deformation of the sliding body 3 which is apparent from FIG.

However, when the electric input and the contact pressure to the piezoelectric body (not shown) fixed to the stator are constant, in this conventional motor structure, a large elastic deformation of the sliding body 3 made of rubber or the like occurs. As a result, the energy loss was large, and, after all, it was extremely difficult to improve the motor efficiency.

Therefore, the present invention is based on the configuration shown in FIG. Also in this case, the vibration waves on the surface generated in the stator 7 move at the speed of the sound velocity U as in the case of FIG.

However, as shown in FIG. 2, in the present invention, the sliding body 5 made of an elastic body having a high friction coefficient is made much thinner than the conventional one, and the sliding body 5 is made flexible. , Energy loss due to its elastic deformation is reduced.

Further, in the present invention, since the support body 6 that constitutes the rotor / mover 4 together with the slide body 5 has flexibility,
The rotor / mover 4 exhibits flexibility as a whole, and the stator 7
The contact area between the sliding wave on the surface and the sliding body 5 is the top 7b of the surface 7a of the stator 7 and its vicinity as in the conventional case, and the high friction coefficient of the sliding body 5 and the rotor / mover 4 as a whole Due to the flexibility, a high frictional force is generated, and the sliding body 5 is driven in the arrow N direction with high efficiency and high output.

FIG. 3 shows an embodiment of the present invention more specifically.

A piezoelectric body 9 is fixed to the stator 8 and a high frequency voltage is applied to the piezoelectric body 9 to generate bending vibration in the stator 8 and transmit the bending vibration to the sliding body 11. This slide body 11 has a high coefficient of friction and is made thin, and a flexible support body 12 allows the entire rotor / mover 13 composed of the slide body 11 and the support body 12 to be flexible. It also has sex.

Therefore, the consumption of deformation energy of the sliding body 11 is suppressed,
A highly efficient and high output motor is realized.

Of course, the present invention is not limited to the above examples. Various details are possible for the details.

〔The invention's effect〕

As described in detail above, according to the present invention, the motor efficiency is greatly improved and the output is increased.

[Brief description of drawings]

FIG. 1 is an enlarged perspective view showing the operation of a conventional ultrasonic motor, and FIG. 2 is an enlarged perspective view showing the operation of the present invention. FIG. 3 is a sectional view showing an embodiment of the present invention. 4 …… Rotator / mover 5 …… Sliding body 6 …… Supporting body 7 …… Stator 8 …… Stator 9 …… Piezoelectric body 10 …… Felt 11 …… Sliding body 12 …… Supporting body 13 …… Rotor / mover 14 …… Shaft 15 …… Bearing

Claims (1)

[Claims] 1. An oscillating wave in which transverse and longitudinal waves are combined is generated,
In a rotor / mover that comes into pressure contact with the surface of a piezoelectric-fixed stator, a flexible sliding body made of an elastic body with a high coefficient of friction that comes into contact with the stator, and a flexible sliding body fixed to this sliding body. A rotor / mover of an ultrasonic motor, characterized in that the rotor / mover is constituted by a flexible support, and the whole rotor / mover is elastically deformed.