JP2703182B2 - Equipment with built-in ultrasonic motor - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device having a built-in ultrasonic motor utilizing ultrasonic vibration, such as a camera. BACKGROUND OF THE INVENTION A prototype of this type of ultrasonic motor has been published in the Asahi Shimbun on August 18, 1985.
In this structure, as shown in FIG. 3, a copper plate 3 is sandwiched between a circular piezoelectric element 1 and a circular piezoelectric element 2, further, they are sandwiched between aluminum rings 4 and 5, and an aluminum torsion connection is made. The child 6 is mounted on the aluminum wheel 4 and is tightened with bolts (not shown). As a driving principle, when the piezoelectric elements 1 and 2 generate longitudinal vibration in the thickness direction, the longitudinal vibration is transmitted to the torsion connector 6 via the aluminum ring 4,
Here, it is converted into torsional vibration. The torsion connector 6 has a wide groove formed in the diameter direction of the connector 6 on the contact surface with the aluminum ring 4 so that the connector 6 is easily bent up and down. The principle is that the rotor 8 pressed against the torsion connector 6 rotates by the torsional vibration. An object of the present invention is to provide an ultrasonic motor built-in device whose configuration is simplified by taking two outputs from a single vibration source by utilizing the characteristics of the ultrasonic motor. Aim. SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, referring to FIG. 2, an ultrasonic motor-equipped device according to the present invention is arranged along the longitudinal direction of the device and has a single unit. And a first output unit (3) that is pressurized at one end of the vibration source and generates a driving force using the vibration of the vibration source.
3) and a rod-shaped ultrasonic motor having a second output section (34) pressurized at the other end of the vibration source and generating a driving force using the vibration of the vibration source. (31) and the output of the first output section (33) and the second output section (34) in a direction substantially orthogonal to the longitudinal direction of the rod-shaped ultrasonic motor, respectively. First and second converting means (38, 39, 41, 42) for converting to an output, first converting means (38, 39) and second converting means (41, 42)
Clutch means (35, 3) for permitting the conversion of one of the conversion means and prohibiting the conversion of the other of the first conversion means (38, 39) and the second conversion means (41, 42).
6). In the ultrasonic motor-equipped device of the present invention, the clutch means may be configured to prohibit the conversion,
One of the first output section (33) and the second output section (34) is in a no-load state. Furthermore, the ultrasonic motor-equipped device of the present invention comprises a first converting means (38, 39).
The output converted by the second conversion means (41, 42) is used for driving the film. According to the present invention, the clutch means (35, 36)
Means that the first conversion means (38, 39) outputs the first output unit (3
When the output of (3) is being converted, the second conversion means (4
, 42), the conversion of the output of the second output section (34) is prohibited, and the second conversion section (41, 42) converts the output of the second output section (34). The conversion of the output of the first output unit (33) by the first conversion means (38, 39) is prohibited. Therefore, it is easy to use and
An ultrasonic motor built-in device having a simple configuration can be realized. When the first converter (38, 39) is converting the output of the first output unit (33), the clutch unit (35, 36) disables the second output unit (34). In the state of the load, the second conversion means (41, 42) outputs the second output unit (3
While converting the output of 4), the second output unit (3
3) is in a no-load state. Therefore, the present invention
It is suitable for use in driving a film of an optical device. FIGS. 1 and 2 show an embodiment of the present invention.
FIG. 2 is a perspective view of an ultrasonic motor, and FIG. 2 is an explanatory diagram when the ultrasonic motor is used for driving a film of a camera.
In FIG. 1, the structure of the ultrasonic motor is a common electrode plate 1.
3 is sandwiched between two piezoelectric elements 11 and 12, and the two piezoelectric elements 11 and 12 are further sandwiched between two horns 14 and 15 from both sides thereof. And the torsion connectors 16 and 1 are attached to the male screw portions 20a and 20b cut at both ends of the bolt 20.
7 are screwed together and integrally tightened. Here, since the drawing is a diagram in which the ultrasonic motor is divided, the axis of the bolt 20 does not appear to be shown where the piezoelectric element and the common electrode plate are drawn. Axis passes from the horn 14 to the horn 15. In addition, the end faces 16 of the torsion connectors 16 and 17
Rotors 18 and 19 are brought into pressure contact with d and 17d by bolts 21 and 22, respectively, using a pressing member (not shown) and a thrust bearing. This torsion connector 1
6, 17 are contact surfaces 16e, 17 with the horns 14, 15;
5e, grooves 16a, 17a wide in the diametric direction and cylindrical portions 16b, 17b having the grooves 16a, 17a.
And at the contact surfaces with the rotors 18 and 19, the grooves 16a,
The projections 16c and 17c are formed by being twisted at a constant angle with respect to the diameter direction of the projection 17a. In this method of supporting the ultrasonic motor, a point at which the vibration displacement of the horns 14 and 15 in the axial direction is zero or nearly zero, that is, a vibration node, may be supported by the external fixed portion using a support. Next, the operation principle of the ultrasonic motor will be described. The two piezoelectric elements 11 and 12 are both polarized so as to vibrate in the thickness direction by applying a voltage (ie,
(One surface of the piezoelectric element is polarized so that one surface is a positive electrode, and the other surface is a negative electrode.) As shown in FIG. 1 using the signs of (+) and (−) with the common electrode plate 13 interposed therebetween. Are arranged in different directions. Accordingly, when an AC voltage having a frequency in the ultrasonic range is applied to the electrodes of the common electrode plate 13 and the horns 14 and 15 of the piezoelectric elements 11 and 12, the piezoelectric elements 11 and 1 are applied.
2 expands and contracts in the thickness direction at the same time, and longitudinal vibration occurs in the horns 14 and 15. The longitudinal vibrations of the horns 14 and 15 are transmitted to the torsional connectors 16 and 17. The contact surface 14 of the horn
The contact surfaces 16e, 17e of the a, 14b, 15a, 15b and the torsional coupler are surfaces that transmit vibration of a displacement of several microns generated by the longitudinal vibration of the piezoelectric elements 11, 12, so that both the flatness and the surface roughness are high. Finished with high precision. As described above, the torsion connectors 16 and 17 have their central portions fastened by the bolts 20 and twisted at a constant angle with respect to the diametrical direction of the grooves 16a and 17a to form the projections 16c and 17c. The torsional couplers 16 and 17 can convert longitudinal vibrations of the horns 14 and 15 into torsional vibrations. Then, the convex portion 1 is formed by the torsional vibration.
When the points on the end faces 16d, 17d of 6c, 17c draw a locus of elliptical motion, the rotors 18, 19, which are in pressure contact with the end faces 16d, 17d, are rotated in a predetermined direction.
The direction of rotation is determined by the grooves 1 of the torsion connectors 16 and 17.
This is determined by the relationship between the radial directions of the projections 16a and 17c and the radial directions of the protrusions 16c and 17c. As shown in FIG. The protrusions 1 are made by matching the radial directions of 16a and 17a.
When the radial directions of 6c and 17c cross each other, the rotation of the rotor 18 in the direction A and the rotation of the rotor 19 in the direction B can be obtained in directions opposite to each other. In order to rotate the two rotors together in the same direction, the radial direction of the grooves 16a and 17a should be set in the same direction in the assembled state of the ultrasonic motor, and the protrusions 16c and 17c should be in the same direction. It is easy to see that the radial directions may be configured in the same direction. The characteristics of this type of ultrasonic motor are high efficiency, low rotation and high torque, so that it can be used as a DD (direct drive) motor for film winding / rewinding of a camera, arm driving of a robot, etc. It can be expected to be applied to those requiring low weight and small space. FIG. 2 shows an embodiment in which the ultrasonic motor is applied to film winding / rewinding of a camera according to the present invention. An ultrasonic motor 31 according to the present invention is provided at the bottom of the camera 30. When the ultrasonic motor 31 is assembled, the groove 32a and the projection 32c of the torsion connector 32 are connected to the groove 1 of the torsion connector 16.
The direction is the same as the radial direction of each of the projections 6a and the projections 16c. Therefore, the rotors 33 and 34 rotate in the same direction. The power transmission members 35 and 36 for transmitting power from the rotors 33 and 34 are gears with a clutch mechanism. The clutch mechanism connects and disconnects the power transmission member and the rotor of the ultrasonic motor. The clutch mechanism connects one of the power transmission members 35 and 36 to the corresponding rotor by a member. Bevel gears 37 and 40 are coaxially arranged on the power transmission members 35 and 36, and bevel gears 37 and 40 are provided with bevel gears 38 and a film rewinding shaft fixed to a film winding shaft. The fixed bevel gear 41 meshes with each other. When winding the film, the clutch mechanism of the power transmission member 35 operates (at this time, the clutch mechanism of the power transmission member 36 is released), and the power transmission member 35 and the rotor 33 are engaged. At this time, since the bevel gear 37 of the power transmission member 35 is engaged with the bevel gear 38 provided on the film winding shaft 39, the film winding shaft 39 is driven to wind the film. When the film is rewound, the clutch mechanism of the power transmission member 36 operates in conjunction with the operation of the externally rewound external operation member (commonly referred to as an R button) of the camera (at this time, power transmission). The clutch mechanism of the member 35 is released), and the power transmission member 36 and the rotor 34 mesh. At this time, since the bevel gear 40 of the power transmission member 36 is engaged with the bevel gear 41 provided on the film rewind shaft, the film rewind shaft 42 is driven to rewind the film. As described above, when one of the rotors is functioning by the clutch mechanism, the other rotor is idle, but the other rotor is configured so that no load (torque) is applied. , There is almost no reduction in efficiency. Further, since this ultrasonic motor does not require a deceleration mechanism, drastic reduction of driving noise, small space, low weight, and low cost can be expected. As described above, according to the present invention, the clutch means permits the conversion of one of the first conversion means and the second conversion means, and the first conversion means and the second conversion means Since the conversion of the other of the conversion means is prohibited, convenience is good,
In addition, a device with a built-in ultrasonic motor having a simple configuration can be realized. Also, the clutch means, in response to the inhibition of the conversion,
Since one of the first output unit and the second output unit is in a no-load state, the efficiency of the ultrasonic motor does not deteriorate. Further, according to the present invention, when the present invention is used for driving a film, it is possible to realize an ultrasonic motor-equipped device having a compact and simple structure.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of an embodiment of an ultrasonic motor according to the present invention. FIG. 2 is an explanatory diagram of an embodiment in which the ultrasonic motor is used for winding and rewinding a film of a camera. FIG. 3 is a perspective view of a prototype example of a conventional ultrasonic motor. [Description of References] 11, 12 ... Piezoelectric elements 14, 15 ... Horn 16, 17 ... Torsional coupler 18, 19 ... Rotor

Claims (1)

(57) [Claims] A single source of vibration located along the length of the instrument
And pressurized at one end of the vibration source to utilize the vibration of the vibration source
A first output section for generating a driving force, and the other end of the vibration source
To generate driving force using the vibration of the vibration source.
A rod-shaped ultrasonic motor having a second output section , and a first output section and a second output section , respectively.
And each output of the first and second output units is
First and second conversion means for converting the output into a direction substantially orthogonal to the longitudinal direction of the ultrasonic motor, and the conversion of one of the first conversion means and the second conversion means And the first conversion means and the second
And a clutch means for inhibiting the other one of the conversion means. 2. 2. The supersonic sound according to claim 1, wherein the clutch unit sets one of the first output unit and the second output unit to a no-load state in response to the inhibition of the conversion. 3.
Equipment with built-in wave motor . 3. 3. The ultrasonic motor according to claim 1, wherein the output converted by the first conversion unit and the second conversion unit is used for driving a film.
-Equipment with built-in data .