JPH11312017A - Position fine adjustment device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain a pressurizing load on an ultrasonic motor in a prescribed state, and to obtain a desired driving force without necessitating any troublesome adjusting work or the like or necessitating working precision or assembly precision in manufacturing. SOLUTION: This position fine adjustment device is provided with a fine moving stage 7 and an ultrasonic motor 1 using a piezoelectric effect for moving the fine moving stage 7 by vibration. Also, this device is provided with a compression spring 2 for allowing the ultrasonic motor 1 to develop a force for pressurizing the fine moving stage 7 in a direction orthogonally crossing the moving direction of the fine moving stage 7, set screw 3, and holder 6. In this constitution, a constant pressurizing force can act from the direction orthogonally crossing the moving direction of the fine moving stage 7 to a sliding board 5 all the time without being affected by the mounting precision of the sliding board 5 in the moving direction of the fine moving stage 7. Thus, the desired driving force by the ultrasonic motor 1 can be obtained allways without necessitating any troublesome adjusting work.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a position fine adjustment device used for a mechanism for adjusting a pressing force of an ultrasonic motor used as an actuator for driving a fine movement stage.

[0002]

2. Description of the Related Art FIG. 5 shows a general structure of a fine movement stage using an ultrasonic motor as an actuator.
In the same figure, the ultrasonic motor 1 has a sliding plate 5
With a predetermined pressing load. The ultrasonic motor 1 generates a traveling wave on the contact surface with the sliding plate 5, and the sliding plate 5 moves in the direction of the arrow A by the frictional force that makes the pressing load a vertical drag. Since the sliding plate 5 is adhered and fixed to the fine moving stage 7, the fine moving stage 7 can be moved together with the sliding plate 5 in the direction of arrow A.

[0003] As described above, the ultrasonic motor 1 moves the fine moving stage 7 by the frictional force that makes the pressing load a vertical reaction force. If the pressing load is too large, the fine moving stage 7 does not move. . Conversely, even if the pressing load is smaller than the appropriate value, the frictional force for moving the fine movement stage 7 becomes small, and the fine movement stage 7 also does not move. From the above, it can be seen that if the pressing load on the sliding plate 5 of the ultrasonic motor 1 is not appropriate, an appropriate driving force cannot be obtained and the fine movement stage 7 does not move.

[0004]

In the structure shown in FIG. 5, the sliding plate 5 of the ultrasonic motor 1 is used as described above.
The pressing load is set by the tightening position of the set screw 3. Therefore, for example, the ultrasonic motor 1 of the sliding plate 5
The surface of the fine contact stage 7 that is in contact with the moving shaft V-V
When the micro-motion stage 7 is not parallel, the distance between the sliding plate 5 and the ultrasonic motor 1 changes with the movement of the fine movement stage 7, and the member to which the set screw 3 is fixed, ie, the ultrasonic motor 1, the set The pressing force increases or decreases according to the rigidity of the series spring composed of the screw 3, the holder 6, the base 100, and the fine movement stage 7.

In general, the rigidity of these members is large, so that a slight change in the position causes a large change in the pressing load. For this reason, processing accuracy at the time of manufacturing these members and accuracy at the time of assembling are required, and there has been a problem that a large amount of labor is required for the adjustment work for ensuring the parallel state.

The present invention has been made in view of the above-mentioned circumstances, and has as its object the purpose of requiring no complicated adjustment work or the like, and not requiring much processing precision and assembly precision at the time of production. In addition, an object of the present invention is to provide a fine position adjustment device for a fine movement stage using an ultrasonic motor capable of obtaining a desired driving force while maintaining a pressing load on the ultrasonic motor in a predetermined state.

[0007]

According to the first aspect of the present invention,
In a fine position adjustment device having a fine moving body and a driving unit using a piezoelectric effect for moving the fine moving body by vibration,
The driving means includes a pressing force generating means for generating a force for pressing the fine moving body in a direction orthogonal to the moving direction of the fine moving body.

With this configuration, it is possible to obtain a desired driving force by applying a predetermined pressing load to the ultrasonic motor as the driving means. According to a second aspect of the present invention, in the first aspect of the present invention, the pressing force generating means is configured using an elastic body.

With this configuration, in addition to the operation of the first aspect of the present invention, it is possible to hold the pressing load on the fine moving body of the ultrasonic motor as the driving means in a predetermined state.

According to a third aspect of the present invention, in the second aspect of the present invention, the pressing force generating means has an adjusting means for adjusting the pressing force by the elastic body. With such a configuration, in addition to the effect of the invention described in claim 2, it is possible to hold the pressing load of the ultrasonic motor as the driving means on the fine moving body at an arbitrary value.

According to a fourth aspect of the present invention, in the first aspect of the present invention, the pressing force generating means is configured using a pantograph mechanism. With such a configuration, in addition to the operation of the invention described in claim 1,
The pressing load on the ultrasonic motor, which is the driving means, can be maintained in a predetermined state without requiring a complicated adjustment operation or the like and not requiring much processing accuracy and assembling accuracy at the time of manufacturing.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects of the present invention, a spherical seat for making point contact between the pressing force generating means and the fine moving body is further provided. .

According to this structure, in addition to the operation of the invention described in any one of the first to fourth aspects, the ultrasonic motor, which is the driving means, is surely provided on the fine moving body in the direction perpendicular to the moving direction. Can be pressed.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A one-axis fine movement stage using an ultrasonic motor according to a first embodiment of the present invention will be described below with reference to the drawings. FIG.
Shows the structure of the ultrasonic motor 1. The ultrasonic motor 1 has a sliding plate 5 having several kilograms by two compression springs 2 arranged inside a holder 6.
It is pressed and contacted with a predetermined pressing load on the order of gf. The pressing force of the compression spring 2 is arbitrarily set by adjusting the screwing amount of the set screw 3 screwed to the holder 6.

The sliding plate 5 is fixed to the fine movement stage 7 by bonding. The ultrasonic motor 1 has a concave portion formed on the upper surface thereof, and a pin 4 attached to a corresponding portion of the holder 6.
As a result, it is loosely fitted to such an extent that the movement in the left-right direction and the rotation around the pin 4 in FIG.

A hemispherical spherical seat 8 is attached to each end of each compression spring 2 on the side that comes into contact with the ultrasonic motor 1. The pressing force due to the elasticity of the compression spring 2 is superimposed by point contact. It is transmitted to the sound wave motor 1.

In the above configuration, the ultrasonic motor 1 is bonded to the fine movement stage 7 with a predetermined pressing force of the order of several kgf by the two compression springs 2 arranged in the holder 6. It is pressed against the plate 5.

Here, the pressing force generated by the compression spring 2 is
Each is set by adjusting the screwing amount of the set screw 3. Note that the movement axis II of the fine moving stage 7 and the sliding direction of the sliding plate 5 are not exactly parallel, and when the fine moving stage 7 moves in the direction indicated by the arrow A in the figure, the sliding plate 5 Even if it oscillates on the order of several tens of μm in the left-right direction of the figure, the variation of the pressing force of the compression spring 2 set by the screwing amount of the set screw 3 given on the order of mm is sufficiently small so that kgf / mm It goes without saying that the spring constant of the compression spring 2 is selected on the order.

Further, as described above, since the ultrasonic motor 1 is loosely fitted by the pins 4 to such an extent that the movement in the left-right direction in FIG. The ultrasonic motor 1 does not receive a moment load due to the inaccurate parallelism between the moving axis II and the longitudinal direction of the sliding plate 5. The pressing force is applied only to the friction surface in the direction perpendicular to the moving direction.

Further, a hemispherical spherical seat 8 is attached to the distal end of the compression spring 2, and the pressing force of the spring 2 is transmitted to the ultrasonic motor 1 by point contact, so that the sliding plate 5
The pressing force is exerted on the friction surface of the first member only in a direction perpendicular to the moving direction.

From the above points, a constant pressing force is always applied to the sliding plate 5 from a direction orthogonal to the moving direction without being influenced by the mounting accuracy of the sliding plate 5 in the moving direction of the fine movement stage 7. It is possible to always obtain a desired driving force by the ultrasonic motor 1 without requiring a complicated adjustment operation.

(Second Embodiment) Hereinafter, a one-axis fine movement stage using an ultrasonic motor according to a second embodiment of the present invention will be described with reference to the drawings. FIG. 2 shows the configuration, which is basically the same as that shown in FIG. 1 above. Therefore, the same parts are denoted by the same reference numerals and description thereof is omitted.

Thus, in place of the compression spring 2 and the set screw 3, the holder 6 is provided with a pantograph mechanism 11 including a tension spring 9 and four pivots 10, and this pantograph mechanism 11 is provided on the distal end side. Spherical seat 8 mounted
Then, the ultrasonic motor 1 is pressed against the sliding plate 5 via the.

In the above configuration, the ultrasonic motor 1 is attached to the fine movement stage 7 by the tension spring 9 of the pantograph mechanism 11 provided on the holder 6 with a predetermined pressing force of the order of several kgf. The moving plate 5 is pressed.

Further, since the ultrasonic motor 1 is loosely fitted by the pins 4 to such an extent that the movement in the left-right direction in the figure and the rotation around the pins 4 are not restricted, the fine movement stage 7
The ultrasonic motor 1 does not receive a moment load due to the inaccurate parallelism between the moving axis II and the longitudinal direction of the sliding plate 5.
A pressing force is applied only to a direction indicated by an arrow B in the figure, which is orthogonal to the moving direction, on the opposed friction surface.

Further, using the pantograph mechanism 11 described above,
Further, a hemispherical spherical seat 8 is attached to the tip of the sliding plate 5 by transmitting the pressing force of the tension spring 9 of the pantograph mechanism 11 to the ultrasonic motor 1 by point contact.
In this case, the pressing force is applied to the friction surface only in a direction perpendicular to the moving direction.

From the above points, a constant pressing force is always applied to the sliding plate 5 from a direction perpendicular to the moving direction without being influenced by the mounting accuracy of the sliding plate 5 in the moving direction of the fine movement stage 7. It is possible to always obtain a desired driving force by the ultrasonic motor 1 without requiring a complicated adjustment operation.

(Third Embodiment) Hereinafter, a one-axis fine movement stage using an ultrasonic motor according to a third embodiment of the present invention will be described with reference to the drawings. FIG. 3 shows the configuration, which is basically the same as that shown in FIGS. 1 and 2 above. Therefore, the same portions are denoted by the same reference numerals and description thereof will be omitted.

The pantograph mechanism 1 shown in FIG.
Instead of 1, a compression spring 2 and a lever mechanism 12 are provided. The lever mechanism 12 has two ends formed of a fixed pivot 12A and a free pivot 12B fixed to the base 100, and the free pivot 12B side on which the ultrasonic motor 1 is mounted is pivotally mounted about the fixed pivot 12A as a rotation center. The other end of the compression spring 2 having one end fixed to the holder 6 is in contact with a position near the free pivot 12B of the coupling portion, and the compression spring 2 is fixed to the free pivot 12B by the elasticity of the compression spring 2. Ultrasonic motor 1 is sliding plate 5
Is pressed.

In the above configuration, the ultrasonic motor 1 is bonded to the fine movement stage 7 with a predetermined pressing force of the order of several kgf by the compression spring 2 disposed on the holder 6 via the lever mechanism 12. It is pressed by the sliding plate 5.

That is, the lever mechanism 12 is
The free pivot 12B side is swingably provided around a fixed pivot 12A fixed to the compression spring 12A.
With this pressing force, the ultrasonic motor 1 attached to the free pivot 12B is pressed against the sliding plate 5 with a constant load.

As described above, the movement axis I-
The ultrasonic motor 1 does not receive a moment load caused by the fact that I is not parallel to the longitudinal direction of the sliding plate 5 accurately, and the ultrasonic motor 1
Exerts a pressing force only on the opposing friction surface of the sliding plate 5 in a direction perpendicular to the moving direction.

From the above points, a constant pressing force is applied to the sliding plate 5 from a direction which is always perpendicular to the moving direction regardless of the mounting accuracy of the sliding plate 5 with respect to the moving direction of the fine movement stage 7. It is possible to always obtain a desired driving force by the ultrasonic motor 1 without requiring a complicated adjustment operation.

(Fourth Embodiment) Hereinafter, a one-axis fine movement stage using an ultrasonic motor according to a fourth embodiment of the present invention will be described with reference to the drawings. FIG. 4 shows the configuration, which is basically the same as that shown in FIGS. 1 to 3 above. Therefore, the same portions are denoted by the same reference numerals and description thereof will be omitted.

Thus, an elastic hinge spring mechanism 13 is provided in place of the lever mechanism 12, the compression spring 2, and the holder 6 of FIG. In the elastic hinge spring mechanism 13, a pair of legs 13a, 13b fixed to the base 100 by screws 14a, 14b with internal through holes, respectively, and a connecting portion 13c connecting the tops of the legs 13a, 13b are integrated. The central portion of the connecting portion 13c is pressed against the ultrasonic motor 1.

The connecting portion 13c has legs 13a, 13b.
(A) are formed at both ends close to, so that rigidity other than the direction of arrow B in the figure, that is, the direction perpendicular to the moving direction of the slide plate 5 and the fine movement stage 7 is reduced. Has been adjusted.

In the above configuration, the ultrasonic motor 1 is pressed by the elastic hinge spring mechanism 13 with a predetermined pressing force on the order of several kgf against the sliding plate 5 adhered to the fine movement stage 7.

That is, in the elastic hinge spring mechanism 13, each leg 13a, 13b is formed on the base 1 by the screws 14a, 14b.
The rigidity in the direction other than the arrow B is reduced by notches formed at both ends of the connecting portion 13c, and the ultrasonic wave is generated only by a simple pressing force that does not generate a moment load or the like. The motor 1 is pressed against the sliding plate 5 with a constant load.

As described above, the moving axis I-
The ultrasonic motor 1 does not receive a moment load caused by the fact that I is not parallel to the longitudinal direction of the sliding plate 5 accurately, and the ultrasonic motor 1
Exerts a pressing force only on the opposing friction surface of the sliding plate 5 in a direction perpendicular to the moving direction.

From the above points, a constant pressing force is applied to the sliding plate 5 from a direction which is always perpendicular to the moving direction of the fine moving stage 7 regardless of the mounting accuracy of the sliding plate 5 in the moving direction. It is possible to always obtain a desired driving force by the ultrasonic motor 1 without requiring a complicated adjustment operation.

It should be noted that the present invention is not limited to those described in the first to fourth embodiments, but can be variously modified and implemented without departing from the gist thereof. .

[0042]

According to the first aspect of the present invention, it is possible to obtain a desired driving force by applying a predetermined pressing load to the ultrasonic motor as the driving means. According to the second aspect of the present invention, in addition to the effect of the first aspect of the present invention, it is possible to hold the pressing load on the fine moving body of the ultrasonic motor as the driving means in a predetermined state.

According to the third aspect of the present invention, in addition to the effect of the second aspect of the present invention, it is possible to hold the pressing load on the fine moving body of the ultrasonic motor as the driving means at an arbitrary value. Become.

According to the fourth aspect of the present invention, in addition to the effects of the first aspect of the present invention, no complicated adjustment work or the like is required, and the processing accuracy and the assembling accuracy at the time of manufacture are not required so much. In both cases, the pressing load on the ultrasonic motor as the driving means can be maintained in a predetermined state.

According to the fifth aspect of the present invention, in addition to the effects of the first to fourth aspects of the present invention, the ultrasonic motor as the driving means is surely perpendicular to the moving direction of the fine moving body. Direction.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a first embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a second embodiment of the present invention.

FIG. 3 is a diagram showing a configuration of a third embodiment of the present invention.

FIG. 4 is a diagram showing a configuration of a fourth embodiment of the present invention.

FIG. 5 is a diagram showing a general configuration of a fine movement stage.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Ultrasonic motor 2 ... Compression spring 3 ... Set screw 4 ... Pin 5 ... Sliding plate 6 ... Holder 7 ... Fine movement stage 8 ... Spherical seat 9 ... Tension spring 10 ... Pivot 11 ... Pantograph mechanism 12 ... Lever mechanism 12A ... Fixed Pivot 12B Free pivot 13 Elastic hinge spring mechanism 13a, 13b Leg 13c Connection 100 Base

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Muneo Takaoki 1-1-1 Wadasaki-cho, Hyogo-ku, Kobe City, Hyogo Prefecture Inside Mitsubishi Heavy Industries, Ltd.Kobe Shipyard

Claims (5)

[Claims] 1. A position fine adjustment device having a fine moving body and a driving means using a piezoelectric effect for moving the fine moving body by vibration, wherein the driving means is arranged in a direction orthogonal to a moving direction of the fine moving body. A fine position adjusting device comprising a pressing force generating means for generating a force for pressing the fine moving body. 2. The position fine-adjustment device according to claim 1, wherein said pressing force generating means comprises an elastic body. 3. The position fine adjustment device according to claim 2, wherein said pressing force generating means has an adjusting means for adjusting the pressing force by said elastic body. 4. The position fine-adjustment device according to claim 1, wherein said pressing force generating means comprises a pantograph mechanism. 5. The position fine-adjustment device according to claim 1, further comprising a spherical seat for bringing said pressing force generating means and said fine moving body into point contact with each other.