JP2003299372A - Actuator with positioning function and electric device with actuator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an actuator with a positioning function, which is excellent in quakeproofing an has high reliability and can perform high-performance positioning control. <P>SOLUTION: This actuator includes a drive part 302 which produces a driving force, a movable body 303 which is operated by the drive part 302, a body 305 to be detected having a part 304 to be read which interlocks with the movable body 303 and provides positional information, a detecting part 306 for detecting the position of the movable body 303 by obtaining the positional information of the body 305 to be detected, a control circuit 324 for transmitting a driving signal to the drive part 302 so that the movable body 303 performs prescribed operation based on a detected signal outputted from the detecting part 306, and a restraining member 307 for restraining operation in one direction among directions other than the operating direction for the body 305 to be detected. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to electronic equipment for controlling the position of a moving body driven by an actuator.

[0002]

2. Description of the Related Art Recently, a technique for controlling the position of a moving body driven by an actuator is used in various electronic devices. As a method of controlling the positioning of the moving body,
For example, there is a method of positioning the moving body by detecting the position information of the moving body that is moved by the driving force of the actuator and performing feedback control of the operation of the moving body based on this position information.

For detecting the position of the moving body, for example, there is an incremental encoder. FIG. 9 shows a plan view of the detected object 200 used in the incremental encoder. It should be noted that FIG. 9 is used for detecting the position of a moving body that rotates. A read portion 201 is provided on the outer peripheral side of the disc-shaped detected body 200. A slit 201a for providing absolute position information of the detected object 200 is provided on the outermost peripheral side of the detected object 200, and a plurality of slit layers 201b for providing information on the amount of movement are provided on the inner peripheral side over two layers. It is provided radially at equal intervals.

The slit provided in the object 200 to be detected is
For example, on one surface of the glass plate, the slit 20
The slits 201a and 201b are formed on the glass plate by forming the vapor deposition film 202 with a metal or the like on the portions other than the portions where the vapor deposition films 1a and 201b are formed, and the portion where the vapor deposition film 202 is present reflects light and the vapor deposition film 202 is not present. The portion can transmit light.

In addition to the object 200 to be detected, the incremental encoder is provided with a detector having a light emitting element and a light receiving element for detecting position information of the object 200 to be detected. By allowing the read portion 201 to pass between the light-emitting element and the light-receiving element provided facing each other, the light emitted from the light-emitting element passes through the object to be detected 200 while the light-receiving element is passing through the slit. While the light is received and the portion other than the slit passes, the light emitted from the light emitting element cannot be transmitted and the light receiving element cannot receive the light.

When a plurality of slits provided at equal intervals pass, the passage of the slits is measured depending on the presence or absence of light reception, and the amount of movement, moving direction, absolute position, etc. are obtained. Positioning of the moving body is performed by feedback control based on this position information.

On the other hand, as an actuator for driving a moving body, an electromagnetic type actuator is often used conventionally. However, in the case of an electromagnetic actuator, the output is small, and furthermore, the positioning resolution of itself is low, so it is generally necessary to drive the moving body by interposing a reduction gear train between the output shaft of the actuator and the moving body. Power and even high resolution are often obtained.

However, since backlash occurs between the gears, there is a possibility that the accuracy and the like when performing the positioning control will deteriorate. Further, a space for providing the reduction gear train is required, which may increase the size of the entire device. Therefore, an ultrasonic actuator may be used as a drive source. Since the ultrasonic actuator has larger torque and higher positioning resolution than the electromagnetic actuator, it is possible to directly drive the moving body without using the reduction gear train.

Further, since the ultrasonic actuator has a holding torque, it does not consume electric power when stopped. for that reason,
Since the problem of backlash does not occur, highly accurate positioning is performed, and it is suitable as a driving source for an actuator with a positioning function that is small and consumes less power.

FIG. 10 is a sectional view of a conventional actuator 100 with a positioning function. In FIG. 10, a rotary drive type ultrasonic actuator 101 is used as a drive source. A central shaft 103 is fixed to a support base 102, a piezoelectric element 104 is adhered to the lower surface, and a protrusion 10 is formed on the upper surface.
A piezoelectric vibrator 106 having 5 is fixed to the central shaft 103. The moving body 107 is supported by the central shaft 103 via a ball bearing 108. The outer ring 108a of the ball bearing 108 is press-fitted into the moving body 107, and the inner ring 108b has the central shaft 103 inserted with a certain gap. The inner ring 108b is pressed by a coil spring 110 via a spring seat 109. The upper end of the coil spring 110 is pressed by a pressing ring 112 fixed to the central shaft 103 via a spring pressing 111.

The moving body 107 is transmitted to the coil spring 11
The piezoelectric vibrator 106 is pressed by a pressing force of 0. When a drive signal is input to the piezoelectric vibrator 106 via the lead wire 113, the piezoelectric vibrator 106 vibrates and the moving body 107
A frictional force is generated between the movable body 10 and the protrusion 105 to generate vibration.
Can be converted into a rotational movement of 7.

An object 114 to be detected is fixed to the moving body 107. The read portion 115 is provided on the outer circumference of the detected object 114.
Is provided. The detection unit 116 includes the read unit 115.
It is provided with a light emitting element 116a and a light receiving element 116b sandwiched between and an element holding portion 117 for holding both.

When the detected body 114 rotates together with the moving body 107, the movement of the read section 115 is detected by the detection section 116. The detection unit 116 transmits this information to the control circuit unit (not shown), and the control circuit unit moves the mobile unit 1 to the target position.
A drive signal is input to the piezoelectric element 104 so that 07 is moved. By such feedback control, the moving body 1
07 positioning is performed.

[0014]

In recent years, positioning control technology for controlling the amount of movement of a moving body driven by an actuator has become indispensable in various electronic devices, and it is becoming increasingly high with the recent industrial development. High-performance positioning control is required. In order to meet this demand, an actuator with a positioning function, which is a combination of an incremental encoder and an ultrasonic actuator, is often used in electronic devices with an actuator.

In order to perform higher resolution positioning control, it is necessary to increase the detection resolution. For that purpose, for example, when the moving body 107 makes a rotational movement, the slit density should be increased with respect to the movement angle. .

To achieve this, there are two methods: a method of increasing the diameter of the object to be detected 114 to increase the area of the portion where the slit is provided, and a method of forming the slit more finely.

In the case of the former method, the disk-shaped object to be detected 11 is detected.
The outermost circumference of 4 is far away from the center of rotation. Therefore, for example, the object to be detected 1 is subject to external impact, vibration, or the like.
When an external force in the vertical direction is applied to the vicinity of the outer circumference of 14, a large force is generated in the central portion of the moving body 107 due to the principle of leverage. When the force exceeds the pressing force of the coil spring 110, the detected body 114 tilts with respect to the center of rotation because a gap exists between the bearing inner ring 108b and the central shaft 103, and the detected body 114 The outermost circumference is largely shaken toward the light receiving element 116b side or the light emitting element 116a side. Further, when vibration occurs inside the detected body 114, the displacement on the outer peripheral side becomes large.

Therefore, the portion to be read 115 is the light emitting element 116a, the light receiving element 116b, or the element holding portion 11.
7 and the like to be read, and the portion to be read 115 and the light emitting element 116a
Alternatively, the light receiving element 116b may be damaged. In particular, when the read portion 115 is formed of a vapor deposition film or the like, the slit shape is likely to be damaged because the scratches are relatively likely to occur, and the position detection accuracy may be deteriorated. Also,
If the light emitting element 116a or the light receiving element 116b is damaged, it may be impossible to detect. Therefore, the reliability of positioning is reduced.

Further, when the detected body 114 largely moves along with the movement of the detected body 114, the moving body 107 and the projection 1
The sliding surface of 05 may be damaged and start-up failure may occur. The distance between the detection object 114 and the light receiving element 116b is increased,
The part to be read 115 includes the light emitting element 116a and the light receiving element 11.
6b or the element holding portion 117 or the like is prevented from coming into contact with the light, the light transmitted through the slit is blurred due to diffraction or the like, and a detection error is likely to occur, resulting in a decrease in detection reliability.

Bearing inner ring 108b for preventing blurring
Although it is sufficient to eliminate the gap between the central axis 103 and the central axis 103, it is necessary to transmit the pressing force to the moving body 107 on the principle of the ultrasonic actuator. Therefore, the moving body 107 must be movable in the thrust direction of the rotating shaft 103. I have to. Therefore, a certain amount of clearance is required between the inner ring 108b and the central shaft 103.

If the gap between the inner ring 108b and the central shaft 103 is reduced, it is possible that the transmission of the pressing force cannot be carried out smoothly and the rotation of the ultrasonic actuator becomes unstable, and in the worst case, it stops.

There is also a method in which the gap between the inner ring 108b and the central shaft 103 is made as small as possible so that the lubricant is interposed in the gap so as not to hinder the transmission of the pressing force. There is a risk that the starting torque of the moving body 107 may decrease due to the flow between the inner ring 108b and the central shaft 1.
Since the amount of movement generated during the period 03 is small, a part of the lubricant layer interposed in the gap is likely to be interrupted, which may hinder the transmission of the pressing force. Although it is conceivable to increase the thickness of the detected body 114 in order to reduce the displacement of the outer peripheral portion due to the vibration of the detected body 114, the inertia of the detected body 114 increases and the responsiveness at the time of positioning control deteriorates. cause.

Further, when the read part 115 vertically moves and the distance between the light receiving element 116b and the read part 115 becomes long during the rotation of the detected object 114, the light transmitted through the slit becomes blurred due to diffraction etc. Is more likely to occur, which lowers the reliability of detection.

In the case of the latter method, the cost is high to form a fine slit, and there is a limit in production technology. Further, the finer the slits, the portion to be read 1
15 becomes difficult to detect, and in order to accurately detect the presence / absence of light in the read portion 115, it is necessary to make the distance between the read portion 115 and the light receiving element 116b shorter, which is similar to the former method. 115 is a light emitting element 116a,
The light receiving element 116b, the element holding portion 117, or the like may come into contact with the light receiving element 115, the light emitting element 116a, or the light receiving element 116b to be damaged.

Further, the finer the slits, the lower the strength of the portion forming the slits, and when a force is applied to the read portion 115, the slit shape is more likely to be damaged.

In view of such circumstances, the present invention is excellent in seismic resistance and reliable even when either or both of the above-mentioned two methods for realizing high-resolution position detection are adopted. An object of the present invention is to provide an actuator with a positioning function and electronic equipment with an actuator that can perform high-performance positioning control.

[0027]

In order to achieve the above object, the present invention provides a driving unit for generating a driving force, a moving body operated by the driving unit, and position information in cooperation with the moving body. For detecting the position of the moving body by obtaining the position information of the detected body, and the moving body based on the signal output from the detecting unit. A control circuit unit that operates the drive unit so as to operate; and at least one suppressing member that suppresses movement of the detected body in a direction other than the predetermined operation direction with respect to the detected body. It is a featured actuator with a positioning function.

According to the present invention, in the actuator with a positioning function described above, the suppressing member is provided on at least one of the drive section and the detection section, and the moving body, the detected body, or It functions by contacting a buffer member provided on the moving body or the detected body.

Further, the present invention is characterized in that, in the actuator with the positioning function described above, the suppressing member is provided at a position where it does not come into contact with the portion to be read.

According to the present invention, in the actuator with a positioning function described above, the suppressing member is provided at a position which does not overlap with the read portion of either the moving body or the detected body, and the detected body is detected. The detection unit or the drive unit, or the detection unit or the drive unit, the shape of the detection unit or the drive unit being one or more provided in the operation direction of the detected unit. It is characterized in that it acts by coming into contact with the cushioning member.

Further, according to the present invention, in the actuator with a positioning function described above, the drive section is an ultrasonic actuator using a vibration generated in the piezoelectric vibrator as a power source.

Further, the present invention is an electronic device with an actuator, comprising: the actuator with a positioning function described above; and a load section movable by the operation of the moving body.

[0033]

DETAILED DESCRIPTION OF THE INVENTION

[0034]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An actuator with a positioning function and an electronic device with an actuator according to the present invention will be described below with reference to the drawings. The following embodiments are merely for the purpose of explaining the present invention and do not limit the scope of the present invention. Therefore, a person skilled in the art can adopt various embodiments including these respective elements or all the elements, but these embodiments are also included in the scope of the present invention.

(First Embodiment) FIG. 8 shows a first embodiment of the present invention.
Electronic Device with Actuator 30 According to Embodiment
It is a block diagram explaining 0. The actuator-equipped electronic device 300 shown in FIG. 8 includes an actuator 301 with a positioning function and a load section 325.
The actuator 301 with a positioning function includes a driving unit 302 that generates a driving force, a moving body 303 that is operated by the driving unit 302, and a read unit 304 that interlocks with the moving body 303 and provides position information. Detecting body 305
And the moving object 30 by obtaining the position information of the detected object 305.
3, a detection unit 306 that detects the position of 3, and a control circuit unit 324 that transmits a drive signal to the drive unit 302 so that the moving body 303 performs a predetermined operation based on the detection signal output from the detection unit 306, The detection member 305 is provided with a suppressing member 307 that suppresses movement in any direction other than the movement direction of the detection target. The load unit 325 is movable by the operation of the moving body 303.

FIG. 1 is a sectional view of an actuator 301 with a positioning function according to the first embodiment of the present invention. In the first embodiment, the drive unit 302 uses a rotary drive type ultrasonic actuator. The principle of the ultrasonic actuator is, for example, JP-A-7-170.
The one described in 772 is used. The drive unit 302 includes the support base 3
08, the central axis 309 fixed to the support base 308, and the piezoelectric element 310 adhered to the lower surface and the protrusion 311 on the upper surface, and the piezoelectric vibrator 3 fixed to the central axis 309 by press fitting.
12, a lead wire 313 that transmits a drive signal sent from the control circuit unit to the piezoelectric element 310 and is joined to the piezoelectric element 310 with solder or the like, and for pressing the moving body 303 against the piezoelectric element 310 via the spring seat 314. Coil-shaped pressure spring 3
15 and a pressing ring 317 that fixes the upper end of the pressure spring 315 to the central shaft 309 via a spring pressing member 316.

The moving body 303 is a ring-shaped sliding plate 318 made of a special resin or the like for improving slidability with respect to the protrusion 311, and a detected body for fixing the detected body 305. A fixing member 320 is provided, and a central shaft 309 is further provided.
A rolling bearing 319 is provided as a bearing for smoothing the relative movement with the.

In order to efficiently transmit the pressure force of the pressure spring 315 to the moving body 303, the outer ring 31 of the bearing 319 is used.
9a is press-fitted into the moving body, but the inner ring 319b has a certain gap with the central shaft 309 so that the central shaft 30
The movable body 303 is movable in the thrust direction with respect to No. 9.

The bearings are not limited to rolling bearings, and sliding bearings or the like may be used.

The drive unit 302 vibrates the piezoelectric vibrator 312 when a drive signal is input, and rotates the moving body 303 pressed against the protrusion 311 via the sliding plate 318 by the pressing force of the pressure spring 315. The to-be-detected object 305 to be driven is fixed by a to-be-detected object fixing member 320 by press fitting, adhesion, screws or the like. It is also possible to directly fix the moving body 303 and the detected body 305 without using the detected body fixing member 320.

The object 305 to be detected has a disk shape, and a reading portion 304 is provided on the lower surface thereof.
The read section 304 is, for example, as shown in FIG.
A large number of radial slits are formed on the outer peripheral side. This slit is formed on a glass flat plate, for example, by forming the detection object 305 with glass or the like that can transmit light and forming a vapor deposition film with a metal or the like on a portion other than the portion where the slit is formed on the disk. Thus, the portion with the vapor deposition film can reflect light, and the portion without the vapor deposition film can transmit light. Further, it is also possible to form the slit in the detected body 305 by forming light with a material such as a metal having poor transparency and removing the portion forming the slit by etching, cutting or the like.

The detecting section 306 includes a light emitting element 321 and a light receiving element 322 so as to sandwich the read section 304, and an element holding section 323 for holding both of them. Here, on the supporting base 308 of the driving section 302. It is fixed to.

When the detected body 305 rotates together with the moving body 303, the detecting section 306 detects the moving amount, moving direction, absolute position, etc. of the read section 304. Detection unit 306
Transmits this information to the control circuit unit, and the control circuit unit inputs a drive signal to the piezoelectric element 310 so that the moving body 303 is moved to the target position. The position of the moving body 303 is positioned at a predetermined place by such feedback control.

By using an ultrasonic actuator for the drive unit 302, it is possible to provide an actuator with a positioning function that is small in size, excellent in responsiveness, and highly accurate.

The suppressing member 307 is integrally formed as a protrusion on the element holding portion 323 of the detecting portion 306.

In general, in order to improve the detection performance, the distance between the light receiving element 322 and the read portion 304 is often relatively short, so that the light receiving element 322 and the read portion 3 are often used.
04 is easy to contact. The suppression member 307 is the detection target 30.
Even if the rotating surface of 5 shakes from a predetermined position due to an impact or the like, the detected body 305 and the suppressing member 307 come into contact with each other before the read portion 304 and the light receiving element 322 come into contact with each other. It functions to prevent the contact between 304 and the light receiving element 322 or the element holding portion 323, and further to prevent the read portion 304 having low strength from being damaged.

Therefore, it is desirable that the suppressing member 307 be installed at a position where it does not come into contact with the read portion 304 even if the rotational surface of the detected body 305 is shaken.

Further, the read portion 304 and the light receiving element 32
It is desirable to make the shortest distance between the detected body 305 and the suppressing member 307 smaller than the shortest distance of 2.

Further, it is desirable that the suppressing member 307 be provided near the straight line connecting the center of rotation of the detection object 305 and the light receiving element 322 and on the outer peripheral side of the reading section 304, which is the detection object 305. When the rotation surface is tilted and shaken, the detected object 305 is more than the shortest distance between the read section 304 and the light receiving element 322 or the element holding section 323.
This is because even if the shortest distance of the suppressing member 307 is made slightly larger, it is possible to prevent contact between the read portion 304 and the light receiving element 322 or the element holding portion 323. However, the suppressing member 307 is in the vicinity of the straight line connecting the rotation center of the detected body 305 and the light receiving element 322,
It may be provided at a location other than the outer peripheral side of the read section 304.

Further, the suppressing member 307 is the element holding portion 323.
Since it is integrally formed with, it can be integrally molded with resin or the like, and is suitable for mass production.

Further, the suppression member 307 is attached to the element holding portion 323.
Since it is provided on the light receiving element 322 side of the
Can be constructed with a small volume and simple shape.

Further, the suppressing member 307 can be provided, for example, on the outer peripheral side of the light receiving element 322, in which case the light receiving element 322 can easily prevent contact with the object 305 to be detected.

Further, the suppressing member 307 may be shaped so as to be in constant contact with the object 305 to be detected, so that more stable surface deviation of the object 305 can be prevented.

Further, in order to widen the area to be received by the object 305 to be detected and to prevent more stable surface deviation of the object 305, the upper end area of the suppressing member 307 is increased or a plurality of suppressing members 307 are provided. May be. Note that the suppressing member 307 may be provided separately from the element holding portion 323, and may be fixed to the element holding portion 323 with an adhesive, a screw, or the like. In this way, the suppression member 307 is provided to suppress the surface deviation of the detected object 305, so that the detected object 3 can be detected for high-resolution position detection.
05, the read portion 304 and the light emitting element 3 due to contact are increased even if the read portion 304 is made fine and the slit density per rotation angle is increased.
21 and the light receiving element 322 are prevented from being damaged, and the detection error of the read portion 304 caused by the change in the distance relationship between the read portion 304, the light emitting element 321, and the light receiving element 322 can be reduced. Since it is not damaged, the pressure applied by the pressure spring 315 is applied to the moving body 30.
3 can be smoothly transmitted to the detection target body 305, the surface deviation of the detection target body 305 can be suppressed, and the performance of the ultrasonic actuator is not impaired by preventing the moving body 303 from being damaged by the protrusion 311 biting in. It is possible to realize the actuator 301 with a positioning function that can perform high-resolution, high-reliability, and high-accuracy positioning without causing problems due to the above.

In addition, the load section 32 that interlocks with the moving body 303.
5 is provided, the electronic device 30 with an actuator is equipped with a load section 325 that is positioned with high resolution, high reliability, and high accuracy without causing problems such as vibration and shock.
0 can be realized.

(Second Embodiment) FIG. 2 is a sectional view of an actuator 401 with a positioning function according to a second embodiment of the present invention. The actuator 401 with a positioning function according to the second embodiment of the present invention is shown in FIG.
The shape of the suppressing member 307 according to the first embodiment of the present invention is modified, and other functions, effects, and the like of the driving unit, the moving body, the detected body, the detection unit, and the control circuit unit are the same as those of the present invention. Actuator 3 with positioning function shown in the first embodiment of
The same as 01.

The suppressing member 402 is on the light receiving element 322 side of the element holding portion 323, in the vicinity of the straight line connecting the rotation center of the detection object 305 and the light receiving element 322, and on the read portion 304.
It is provided on the outer peripheral side.

The suppressing member 402 has an L-shaped cross section, and the upper surface 402a of the L-shaped inner corner side is the lower surface of the object 305 and the side surface 402b of the L-shaped inner corner is the object to be detected. It is possible to receive the outer peripheral side surface of the body 305.

Therefore, in addition to suppressing the surface deviation of the detected object 305 due to vibration, etc., there is a problem that the rotation axis of the detected object 305 and the central axis 309 are displaced or the central axis 309 itself vibrates. Even if the
It is possible to suppress the axial blurring of the object, and to suppress the blurring of the light receiving element 322 and the read portion 304 in the radial direction of the detected object 305. Therefore, the actuator 3 with the positioning function shown in the first embodiment of the present invention
It is possible to further reduce the occurrence of the detection error of the read portion 304 compared with 01.

Further, the suppressing member 307 may have a U-shaped cross section to suppress the surface deviation of the object 305 to be detected. As described above, the suppression member 402 is provided to suppress the surface deviation of the detected object 305, thereby increasing the size of the detected object 305 for high-resolution position detection or by rotating the read part 304 to be fine. Even when the slit density per angle is increased, the read portion 304, the light emitting element 321, the light receiving element 322, and the like are prevented from being damaged by contact, and the read portion 304 and the light emitting element 32 are prevented.
1 and the light receiving element 322, the detection error of the read portion 304 caused by the change in the distance relationship can be reduced, so that the detection performance is not impaired.
While smoothly transmitting the pressing force of 15 to the moving body 303,
Since the surface deviation of the detected body 305 can be suppressed, and the performance of the ultrasonic actuator is not impaired by preventing the moving body 303 from being damaged by the protrusion 311 biting in,
It is possible to realize the actuator 401 with a positioning function capable of performing high-resolution, high-reliability, and high-accuracy positioning without causing problems such as vibration and shock.

(Third Embodiment) FIG. 3 is a sectional view of an actuator 501 with a positioning function according to a third embodiment of the present invention. An actuator 501 with a positioning function according to a third embodiment of the present invention is shown in FIG.
The shape and the installation location of the suppressing member 307 according to the first embodiment of the present invention are changed, and other drive units,
The functions, effects, and the like of the moving body, the detected body, the detection unit, and the control circuit unit are the same as those of the actuator 301 with the positioning function shown in the first embodiment of the present invention.

The suppressing member 502 is provided near the detecting portion 306 and is fixed to the support base 308. Since the suppressing member 502 is fixed to the support base 308, the suppressing member 502 can be made of a metal or the like that can be easily processed, and can be easily attached by press fitting or the like. Therefore, the production cost can be suppressed, and the actuator 501 with a high-performance positioning function can be provided at a low price.

Further, since the suppressing member 502 is installed in the vicinity of the detecting portion 306, the detected object 30 can be stably maintained.
The surface runout of No. 5 can be suppressed. Further, a plurality of suppressing members 502 can be installed on the support base 308 for more stability. By providing the suppression member 502 in this way to suppress the surface deviation of the detected object 305, the detected object 305 is made large in size for high-resolution position detection, or the read part 304 is made fine to rotate. Even when the slit density per angle is increased, damage to the read portion 304, the light emitting element 321, the light receiving element 322, and the like due to contact is prevented, and the distance relationship between the read portion 304, the light emitting element 321, and the light receiving element 322 is large. The detection error of the read part 304 caused by the change of the detection target can be reduced, the detection performance is not impaired, and the detection target 305 can be transmitted while smoothly transmitting the pressure applied by the pressure spring 315 to the moving body 303. Surface protrusion of the protrusion 31 can be suppressed.
Since the performance of the ultrasonic actuator is not impaired by preventing the moving body 303 from being damaged due to the bite of No. 1, positioning that enables high-resolution, high-reliability and highly-accurate positioning without causing problems due to vibration, shock, etc. The actuator 501 with a function can be realized.

(Fourth Embodiment) FIG. 4 is a sectional view of an actuator 601 with a positioning function according to a fourth embodiment of the present invention. An actuator 601 with a positioning function according to the fourth embodiment of the present invention is shown in FIG.
The shape and the installation location of the suppressing member 307 according to the first embodiment of the present invention are changed, and other drive units,
The functions, effects, and the like of the moving body, the detected body, the detection unit, and the control circuit unit are the same as those of the actuator 301 with the positioning function shown in the first embodiment of the present invention.

The suppressing member 602 is located on the straight line connecting the center of rotation of the object to be detected 305 and the light receiving element 322 in the vicinity of the side opposite to the light receiving element 322 and the center of rotation by 180 degrees, and is located at the outer periphery of the read part 304 of the object to be detected 305. It is provided on the side.

In this case, in order to prevent the read portion 304 from contacting the light receiving element 322 and the element holding portion 323,
When viewed from the suppressing member 602, it is necessary to suppress the inclination of the surface deviation of the detection object 305 from moving upward. Therefore, the suppressing member 602 is
Since it functions by contacting the upper surface of the detected object 305, it is shaped so as to cover the upper surface of the detected object 305.

At the same time, it has a U-shaped cross-sectional shape so as to be able to suppress a surface shake and a shaft shake that are inclined downward as viewed from the suppressing member 602.

Further, since the suppressing member 602 is fixed to the support base 308 of the drive section 302 by press fitting, it is possible to provide an inexpensive actuator 601 having a positioning function.

Further, the light emitting element 321 and the light receiving element 322
Since the suppressing member 602 is installed at a position sufficiently distant from, the abrasion powder that may be generated when the suppressing member 602 and the detection object 305 come into contact with each other does not adhere to the light emitting element 321 and the light receiving element 322. The abrasion powder does not block the light, and the detection accuracy does not deteriorate.

The fourth embodiment is very effective when it is difficult to install the suppressing member 602 in the detecting section 306 or in the vicinity of the detecting section 306. In this way, the suppressing member 6
02 is provided to suppress surface deviation of the detected object 305,
Even when the size of the detected object 305 is increased in order to detect the position with high resolution, or the slit density per rotation angle is increased by making the read part 304 fine,
Damage to the read portion 304, the light emitting element 321, the light receiving element 322, and the like due to contact is prevented, and the read portion 30
4. Since the detection error of the read portion 304 caused by the change in the distance relationship of the gap between the light emitting element 321 and the light receiving element 322 can be reduced, the detection performance is not impaired, and the pressure applied by the pressure spring 315 can be reduced. While smoothly transmitting to the moving body 303, surface deviation of the detected body 305 can be suppressed, and the performance of the ultrasonic actuator is not impaired by preventing damage to the moving body 303 due to the biting of the protrusion 311. Thus, it is possible to realize the actuator 601 with a positioning function capable of high-resolution, high-reliability, and high-accuracy positioning without causing problems such as impact.

(Fifth Embodiment) FIG. 5 is a sectional view of an actuator 701 with a positioning function according to a fifth embodiment of the present invention. An actuator 701 with a positioning function according to a fifth embodiment of the present invention is shown in FIG.
The shape and the installation location of the suppressing member 307 according to the first embodiment of the present invention are changed, and other drive units,
The functions, effects, and the like of the moving body, the detected body, the detection unit, and the control circuit unit are the same as those of the actuator 301 with the positioning function shown in the first embodiment of the present invention.

The restraint member 702 is placed at a position where it does not overlap the read portion 304 so as not to interfere with the position detection, and
It is fixed to the outer peripheral side of the to-be-read portion 304 of 05 by adhesion or the like. Further, the planar shape of the suppressing member 702 is a ring shape that is concentric with the disk-shaped detected body 305. The suppressing member 702 is the read portion 3 of the detected object 305.
04, and the suppression member 702 has a ring-shaped planar shape, so that the detected object 30 can be stably obtained.
The surface runout of No. 5 can be suppressed.

Further, since the suppressing member 702 has a ring shape and is provided on the member itself which rotates and moves, the suppressing member 70
The contact surface of 2 does not concentrate in one place, and the suppressing member 7
02 wear is reduced. Therefore, durability is improved.
The suppressing member 702 may be provided on the inner peripheral side of the read portion 304. In this way, the suppressing member 702
By suppressing the surface deviation of the detection target 305, the size of the detection target 305 is increased in order to perform high-resolution position detection, or the read unit 304 is made fine to reduce the slit density per rotation angle. Even when the number is increased, damage to the read portion 304, the light emitting element 321, the light receiving element 322, and the like due to contact is prevented, and the distance relationship of the gap between the read portion 304, the light emitting element 321, and the light receiving element 322 changes. Since the detection error of the reading unit 304 can be reduced, the detection performance is not impaired, and the surface deflection of the detected object 305 can be suppressed while smoothly transmitting the pressure applied by the pressure spring 315 to the moving body 303. , Protrusion 3
Since the performance of the ultrasonic actuator is not impaired by preventing damage to the moving body 303 due to the biting in of 11, positioning with high resolution, high reliability, and high accuracy that does not cause problems due to vibration, shock, etc. The actuator with function 701 can be realized.

(Sixth Embodiment) FIG. 6 is a sectional view of an actuator 801 with a positioning function according to a sixth embodiment of the present invention. An actuator 801 with a positioning function according to a sixth embodiment of the present invention is shown in FIG.
The shape and the installation location of the suppressing member 307 according to the first embodiment of the present invention are changed, and other drive units,
The functions, effects, and the like of the moving body, the detected body, the detection unit, and the control circuit unit are the same as those of the actuator 301 with the positioning function shown in the first embodiment of the present invention.

The restraining member 802 is formed in a circumferential shape integrally with the moving body 303. Therefore, the suppressing member 802 can be created by shaving when the moving body 303 is processed by a lathe or the like. Therefore, the processing is easy and the assemblability is improved. As described above, the suppression member 802 is provided to suppress the surface deviation of the detected object 305, thereby increasing the size of the detected object 305 to perform high-resolution position detection or by rotating the read part 304 to be fine. Even when the slit density per angle is increased, the read portion 304, the light emitting element 321, the light receiving element 322, and the like are prevented from being damaged by contact, and the read portion 304 and the light emitting element 32 are prevented.
1 and the light receiving element 322, the detection error of the read portion 304 caused by the change in the distance relationship can be reduced, so that the detection performance is not impaired.
While smoothly transmitting the pressing force of 15 to the moving body 303,
Since the surface deviation of the detected body 305 can be suppressed, and the performance of the ultrasonic actuator is not impaired by preventing the moving body 303 from being damaged by the protrusion 311 biting in,
It is possible to realize the actuator 801 with a positioning function that can perform high resolution, high reliability, and highly accurate positioning without causing problems due to vibration, shock, and the like.

(Seventh Embodiment) FIG. 7 shows an electronic device 9 with an actuator according to a seventh embodiment of the present invention.
It is sectional drawing of 01. An electronic device 901 with an actuator according to the seventh embodiment of the present invention has an actuator 902 with a positioning function and a load section 904 that is movable by the operation of the moving body 303.

Actuator 902 with positioning function
Is a modification of the shape and installation location of the suppressing member 307 according to the first embodiment of FIG. 1, and other functions of the drive unit, the moving body, the detected body, the detection unit, and the control circuit unit. The effects and the like are similar to those of the actuator 301 with a positioning function shown in the first embodiment of the present invention. Two suppressing members 903 are installed so as to sandwich the detected body 305 in the element holding portion 323. The suppression member 903a is installed on the light emitting element 321 side, and has a function of suppressing upward blurring of the detected body 305. In addition, the suppressing member 9
03b is installed on the light receiving element 322 side and has a function of suppressing downward blurring of the detected body 305.

The suppressing member 903 is provided with the center of rotation and the light receiving element 32.
It is provided in the vicinity of the straight line connecting the two, at a position where it does not contact the read portion 304, and in the vicinity of the read portion 304. Further, the detected object 305 is a cushioning member 907.
The cushioning member 907 comes into contact with the suppressing member 903 when the rotating surface of the detected object 305 shakes. Buffer member 90
7a has a function of contacting the suppressing member 903a, and the buffer member 907b has a function of contacting the suppressing member 903b. The cushioning member 907 is preferably made of a highly lubricious material to reduce friction at the time of contact. It is also preferable to use a material having an appropriate elasticity to reduce the impact at the time of contact.

The load section 904 is fixed to the moving body 303 via a mounting member 907 here. The moving body is screwed upward, and a mounting member 907 having a shape that allows the central shaft 309 to escape is fixed by the screw, and the load portion 904 is attached to the upper surface of the mounting member 907.
Are fixed by adhesion. The load unit 904 is the moving body 3
Since the movable body 303 is moved by the operation of 03 and the positioning control of the moving body 303 is performed, the load portion 904 is similarly positioned. The load portion 904 has a mirror surface 904a here, and functions as a mirror that reflects light.

As a result, the mirror surface 904a of the load section 904 is formed.
Is a light control device capable of controlling the position of the moving body 303 by reflecting the light beam 905 emitted from above the load portion 904 on the mirror surface 904a and controlling the direction of the reflected light 906 by the position of the moving body 303. realizable.

It is also possible to realize an optical control device that changes the wavelength, intensity, etc. of light by using a filter or the like whose wavelength and intensity are transmitted depending on the position as the load section. These optical control devices can be applied in the fields of optical communication devices, measuring devices, medical devices, and the like. It is also possible to realize an indicator device or the like that changes the position to be instructed according to the position of the moving body by using a pointer or the like used for a display part of a timepiece or a measuring device as a load part. As described above, the suppression member 903 is provided to suppress the surface deviation of the detected object 305, thereby increasing the size of the detected object 305 for high-resolution position detection or by rotating the read part 304 to be fine. Even when the slit density per angle is increased, damage to the read portion 304, the light emitting element 321, the light receiving element 322, and the like due to contact is prevented, and the read portion 3
04, since the detection error of the read portion 304 caused by the change in the distance relationship of the gap between the light emitting element 321 and the light receiving element 322 can be reduced, the detection performance is not impaired.
Further, it is possible to smoothly transfer the pressure applied by the pressure spring 315 to the moving body 303 and suppress the surface deviation of the detected body 305.
Since the performance of the ultrasonic actuator is not impaired by preventing damage to the moving body 303 due to the protrusion 311 biting in, it is possible to perform high-resolution, high-reliability, and high-accuracy positioning without causing problems such as vibration and shock. The actuator 902 having a simple positioning function can be realized.

Further, the load section 90 interlocking with the moving body 303.
By providing No. 4, it is possible to realize an electronic device with an actuator that includes a load section 904 that is positioned with high resolution, high reliability, and high accuracy without causing problems such as vibration and shock. Although the moving body is directly driven by the drive unit in the embodiments shown in FIGS. 1 to 8 described above, the moving body may be driven via a power transmission mechanism such as a reduction gear train. .

Further, in order to prevent damage to the contact portion on the other side with which the suppressing member comes into contact and improve lubricity, the material of the suppressing member should be one having appropriate elasticity, or the suppressing member or the other side with which the suppressing member contacts. It is also preferable to provide a cushioning member to absorb the shock and improve the wear resistance and lubricity of the contact surface.

Further, in order to reduce the friction of the portion where the contact occurs and reduce the load on the operation of the moving body, the portion where the contact of the suppressing member may occur is made of resin or oil-containing material having good lubricity, or the contact is suppressed. Lubricating oil or the like may be applied to a portion that may occur. Further, although the suppressing member has a function of suppressing the shake of the detected object by the sliding contact, it is possible to provide a wheel or the like on the suppressing member or a side on which the suppressing member comes into contact so as to make rolling contact.

Further, it is also possible to adopt a configuration in which the suppressing member is always in contact with the other side with which the object to be detected is contacted in order to suppress the object to be shaken, and more stably suppresses the object to be shaken. Further, the contact surface of the suppressing member may have a large area for stably suppressing the shake of the detection target, and may have a narrow area for reducing the frictional resistance due to the contact.

The suppressing member may be installed near the center of rotation in order to reduce the torque loss due to contact friction. Further, although the suppressing member uses contact as the principle of operation, it may have a function of suppressing the shake of the detection target in a non-contact manner by using magnetic force or the like. Further, the installation place of the suppressing member is not limited to the place constituting the actuator with a positioning function of the present invention, and may be installed in, for example, an electronic device in which the actuator with a positioning function is incorporated.

It is also possible to combine a plurality of suppressing members having various shapes, installation locations, installation numbers, principles, etc., as described above, and in this case, more stable performance can be obtained. Furthermore, although the ultrasonic actuator is used as a drive source in the actuator with a positioning function shown in the first to seventh embodiments, it can be applied to actuators of various principles such as electromagnetic actuators. The encoder is not limited to the incremental type, and the principle is not limited to the optical type. Further, the movement of the moving body is not limited to the rotational movement.

[0088]

As described above, according to the present invention, it is possible to provide a high-performance actuator with a positioning function that is highly resistant to earthquakes and highly reliable while realizing high-resolution position detection.

[Brief description of drawings]

FIG. 1 is a sectional view of an actuator 301 with a positioning function according to a first embodiment of the present invention.

FIG. 2 is a sectional view of an actuator 401 with a positioning function according to a second embodiment of the present invention.

FIG. 3 is a sectional view of an actuator with positioning function 501 according to a third embodiment of the present invention.

FIG. 4 is a sectional view of an actuator 601 with a positioning function according to a fourth embodiment of the present invention.

FIG. 5 is a sectional view of an actuator 701 with a positioning function according to a fifth embodiment of the present invention.

FIG. 6 is a sectional view of an actuator 801 with a positioning function according to a sixth embodiment of the present invention.

FIG. 7 is a sectional view of an electronic device with actuator 901 according to a seventh embodiment of the present invention.

FIG. 8 is a block diagram illustrating an electronic device with an actuator 300 according to the first embodiment of the present invention.

FIG. 9 is a plan view of an object to be detected 200 used in an actuator with a positioning function.

FIG. 10 is a cross-sectional view of a conventional actuator 100 with a positioning function.

[Explanation of symbols]

300,901 Electronic devices with actuators 301, 401, 501, 601, 701, 801, 9
02 Actuator with positioning function 302 Drive part 303 Moving body 304 Read part 305 Detected body 306 Detection parts 307, 402, 502, 602, 702, 802, 9
03 Suppression member 308 Support base 309 Central axis 310 Piezoelectric element 311 Projection part 312 Piezoelectric vibrator 313 Lead wire 314 Spring seat 315 Pressure spring 316 Spring retainer 317 Presser ring 318 Sliding plate 319 Bearing 319a Outer ring 319b Inner ring 320 Fixed target object Member 321 Light emitting element 322 Light receiving element 323 Element holding part 324 Control circuit parts 325, 904 Load part 907 Buffer member 200 Detected body 201 Read part 201a Slit 201b Slit layer 202 Vapor deposition film 100 Conventional actuator with positioning function 101 Ultrasonic actuator 102 support base 103 central shaft 104 piezoelectric element 105 protrusion 106 piezoelectric vibrator 107 moving body 108 ball bearing 108a outer ring 108b inner ring 109 spring seat 110 coil spring 111 spring retainer 11 Retaining ring 113 leads 114 the detected body 115 to be read unit 116 detecting unit 116a emitting element 116b light-receiving element 117 element holding member

Continued front page    (72) Inventor Yukio Akiyama             1-8 Nakase, Nakase, Mihama-ku, Chiba City, Chiba Prefecture             Ico Instruments Co., Ltd. (72) Inventor Takayuki Kosaka             1-8 Nakase, Nakase, Mihama-ku, Chiba City, Chiba Prefecture             Ico Instruments Co., Ltd. F term (reference) 2F077 AA25 AA49 CC02 NN02 NN23                       NN30 PP19 QQ01 VV01 VV14                 2F103 BA08 BA17 BA37 CA02 DA01                       DA13 EA12 EB01 EB11 EB23                       EB33 GA04                 5H680 BB01 BB16 BC08 BC10 CC02                       DD01 DD12 DD23 DD35 DD53                       DD55 DD65 DD73 EE22 FF24                       FF30

Claims (6)

[Claims] 1. A drive unit that generates a drive force, a moving body that is operated by the drive unit, and a detected body that includes a read unit that is interlocked with the moving body and provides position information. A detection unit that detects the position of the moving body by obtaining position information of the detected body, and drives the drive unit so that the moving body performs a predetermined operation based on a signal output from the detection unit. An actuator with a positioning function, comprising: a control circuit section for controlling the detection target; and at least one suppression member that suppresses movement of the detection target in a direction other than the predetermined operation direction with respect to the detection target. 2. The suppression member is provided on at least one of the drive unit and the detection unit, and is provided in the moving body, the detected body, or a buffer provided in the moving body or the detected body. The actuator with a positioning function according to claim 1, which functions by contacting a member. 3. The actuator with a positioning function according to claim 1, wherein the suppressing member is provided at a position where it does not come into contact with the read portion. 4. The suppressing member is provided at a position that does not overlap with the read portion of either the moving body or the detected body, and has a shape extending in the operation direction of the detected portion. Alternatively, at least one is provided in the operation direction of the detected part, and it operates by contacting the detection part, the drive part, or the buffer part provided in the detection part or the drive part. The actuator with a positioning function according to claim 1. 5. The actuator with a positioning function according to claim 1, wherein the drive unit is an ultrasonic actuator using a vibration generated in a piezoelectric vibrator as a power source. 6. An electronic device with an actuator, comprising: the actuator with a positioning function according to claim 1; and a load section movable by an operation of the moving body.