JPH0717277Y2 - Ultrasonic motor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an ultrasonic motor for generating a rotational motion by generating a traveling wave by vibration of a piezoelectric body.

[Conventional technology]

Most of the various motor devices that have been widely used in the past apply electromagnetic force as a drive source, and are used for various purposes. On the other hand, instead of electromagnetic force,
As disclosed in Japanese Patent Application Laid-Open No. 58-148682, there is proposed an ultrasonic motor in which the powerful vibration energy of ultrasonic waves is converted into rotation or linear motion to facilitate miniaturization and weight reduction. In this ultrasonic motor, when a high frequency voltage is applied to the piezoelectric ceramics stretched on the back surface of the stator, the stator vibrates, and when viewed at one point of the stator, this vibration makes an elliptical motion. The rotor is pressed against the stator by a spring force via the lining. The rotor is rotated by the vibration of the stator, and the shaft that is frictionally connected to the rotor via the packing and the spring is rotated.

[Problems to be solved by the invention]

When high frequency power is supplied to the piezoelectric element, the rotor rotates and the shaft rotates, but when power supply is stopped, the rotor is pressed against the stator by spring force, and the rotating shaft is locked. . When an ultrasonic motor is used for an electric shutter in which a drive unit is arranged at a high place, the motor is usually turned on and off by a hand switch or a remote control. However, there is a drawback that the shutter cannot be opened manually in an emergency or during a power failure.

The present invention aims to eliminate this drawback.

[Means for solving problems]

In order to achieve the above object, the present invention provides a casing 2, a shaft 6 rotatably supported by the casing 2, a stopper 14 fixed to the shaft 6, and a piezoelectric body fixed to the casing 2. A stator 8 in which 10 is stretched and a rotor 12 which is rotatably supported by the shaft 6 and abuts on the stator 8.
And a spring 16 disposed between the stopper 14 and the rotor 12 to press the rotor 12 against the stator 8 with the stopper 14 as a fulcrum and to frictionally connect the rotor 12 and the stopper 14 to each other. An AC voltage is applied to the body 10 to generate ultrasonic vibrations in the stator 8 to rotate the rotor 12 in pressure contact with the stator 8.
In an ultrasonic motor configured to rotate a shaft 6 that is frictionally coupled with, the levers 24 and 32 for manual operation are swingably supported on the casing 2, and the levers 24 and 32 are
The pressure members 24a and 30 are connected to the pressure members 24a and 30, and the pressure members 24a and 30 press the spring force 16 by swinging the levers 24 and 32 to release the pressure contact force of the spring 16 with respect to the stopper 14. The pressing members 24a and 30 are arranged so as to face the spring 16.

[Action]

In the above configuration, when the ultrasonic motor is stopped,
When the lock release mechanism is activated to release the frictional coupling between the rotor 12 and the shaft 6, the shaft 6 becomes free to rotate with respect to the rotor 12.

〔Example〕

The structure of the present invention will be described below with reference to the embodiments shown in the accompanying drawings.

Reference numeral 2 denotes a casing, to which a shaft 6 is rotatably attached via a bearing 4. A stator 8 is integrally fixed to the casing 2. A piezoelectric element 10 made of piezoelectric ceramic is attached to one side surface of the stator 8 on the outer side in the radial direction. A rotor 12 is in contact with the other side surface of the stator 8. An inner diameter portion of the rotor 12 is rotatably fitted on the shaft 6. A stopper 14 is fixedly mounted on the shaft 6, and a bulky spring 16 and a packing 18 are arranged between the stopper 14 and the rotor 12. The spring 16 elastically presses the rotor 12 around the stopper 14 as a fulcrum, and the elastic force presses the rotor 12 against the stator 8. A cover 22 is fixed to the bearing 20 fitted to one end of the shaft 6 and the casing 2. The cover
A lever 24 is rotatably supported on the outside of 22. One end of the lever 24 is inserted into the cover 22 and the spring 16
Extends in the vicinity of the inner peripheral edge of the. The tip of the lever 24 is L-shaped.

In the above structure, when an AC voltage is applied to the piezoelectric element 10, the stator 8 vibrates and the rotor 12 rotates by the force of the traveling wave. The rotation of the rotor 12 is transmitted to the stopper 14 by a frictional force through the packing 18 and the spring 16, and the shaft 6 rotates.

When the power supply to the piezoelectric element 10 is stopped, the vibration of the stator 8 is stopped, the rotor 12 is pressed against the stator 8 by the elastic force of the spring 16, and the shaft 6 is locked on the side of the stator 8.

To release this locked state, rotate the lever 24 about 90 degrees. By this rotation, the L-shaped portion 24 at the tip of the lever 24
As a rotates, the L-shaped portion 24a presses the vicinity of the inner diameter of the spring 16. As a result, the spring 16 is separated from the stopper 14, and the shaft 6 is free from the stator 8.

The lever 24 constitutes a lock release mechanism. next,
Another embodiment of the lock release mechanism will be described with reference to FIG.

Reference numeral 28 denotes a ring-shaped cam receiver fixedly provided on the inner surface of the cover 22, and a disc-shaped cam 30 is rotatably provided along the lower cam surface of the ring-shaped cam receiver. The cam 30 is provided with the cam receiver 28.
It is configured to move in the axial direction when it is rotated in the circumferential direction along the cam surface. A lever 32 is attached to one end of the cam 30, and a tip end of the lever 32 is arranged outside through a long hole formed in the cover 22 in a circumferential direction. The lower surface of the cam 30 is arranged on the upper surface of the inner diameter portion of the spring 16. The lever 32 has a cam
30 is positioned so as to be the most retracted position (the highest position in FIG. 3). Normally, the lower end (tip) of the cam 30 is the spring 16
No pressure is applied to. When releasing the lock, when the lever 32 is rotated approximately 90 degrees in a predetermined direction along the long hole of the cover 22, the cam 30 moves forward along the cam surface of the cam receiver 28 in the downward direction along the shaft 6 along the shaft 6. Then, the cam 30 presses the spring 16 to release the pressure contact force of the spring 16 with respect to the stopper 14,
The shaft 6 is free from the stator 8.

As described above, according to the present invention, the ultrasonic motor is provided with the manual unlocking mechanism for releasing the locked state of the shaft. Therefore, it is desired to freely move the transmission shutter in which the ultrasonic motor is arranged at a high place from the stopped state. In this case, there is an effect that this can be easily and inexpensively performed by setting the shaft of the ultrasonic motor in a free state.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view, FIG. 2 is a plan view, and FIG. 3 is a sectional view of another embodiment. 2 ... Casing, 8 ... Stator, 10 ... Piezoelectric ceramics, 12 ... Rotor, 16 ... Spring, 18 ... Packing, 6 ...
Shaft, 4 …… Bearing, 14 …… Stopper, 22 …… Cover, 24 ……
lever

Claims (1)

[Scope of utility model registration request] 1. A casing (2) and the casing (2).
A shaft (6) rotatably supported by the shaft, a stopper (14) fixed to the shaft (6), and a piezoelectric body (10) fixed to the casing (2). (8),
The stator (8) is rotatably supported by the shaft (6).
A rotor (12) that abuts against the rotor (12), and the rotor (12) is disposed between the stopper (14) and the rotor (12) with the stopper (14) as a fulcrum to press the rotor (12) to the stator (8), 12) and a spring (16) for frictionally coupling the stopper (14), an alternating voltage is applied to the piezoelectric body (10) to generate ultrasonic vibrations in the stator (8), In an ultrasonic motor in which the rotor (12) pressed against 8) is rotated and the shaft (6) frictionally coupled to the rotor (12) is rotated, the casing (2) is manually operated. Lever (24)
(32) is swingably supported, the pressure members (24a) (30) are connected to the levers (24) (32), and the levers (24) (3) are connected.
By the swinging of (2), the pressing members (24a) (30) pressurize the spring force (16) and the stopper (1) of the spring (16).
4) The pressing member (24
a) An ultrasonic motor in which (30) is arranged so as to face the spring (16).