JP3133886U - Rotary positioning stage - Google Patents

Abstract

Provided is a rotary positioning stage that is capable of highly accurate angle correction with a simple structure and has few projections from the periphery of a rotary table.
A main body 2, a rotary table 3, a shaft 6, a stepping motor 5, and a plate cam 4 are provided. A stepping motor 5 is arranged on the lower surface side of the turntable 3 and its output shaft 9 is arranged in parallel with the shaft 6 of the turntable 3. The plate cam 4 is disposed on the lower surface side of the turntable and overlaps with the turntable 3 and the stepping motor 5. A drive pin 13 protruding from the rotary table 3 is brought into contact with the cam circumferential surface of the plate cam 4 and means for constantly urging the drive pin 13 toward the plate cam side is provided.
[Selection] Figure 1

Description

  The present invention relates to an apparatus for correcting the angle of a workpiece (processing object).

In order to perform accurate processing / assembly or inspection in the course of conveyance by an automatic assembling machine or inspection machine or in the process of assembling / inspecting, it is important to place the workpiece as an object at the correct angular position.
For this purpose, there is provided a rotary stage in which a work is placed on a rotary table and the rotary table is rotated to correct the angular position based on a separately detected angular deviation (rotational direction deviation) of the work. (Patent Documents 1 to 3).

  The rotation stage of Patent Document 1 is a device in which a mounting table (stage) 1 having a rotary bearing is rotated slightly by an actuator (inch worm) 6 using a piezoelectric element as a drive source. This document 1 also describes a conventional example using a ball screw 3 driven by a pulse motor 5. It is easily conceivable to use a ball screw as a worm gear.

An apparatus for positioning a disk-shaped body such as a wafer 10 disclosed in Patent Document 2 corrects an angular position of a disk-shaped body such as a wafer 10 placed on the rotary stage 2, and rotates the rotary stage 2. A position shift angle and a position shift distance between the center and the center position of the wafer 10 are detected, the rotation stage is corrected according to the position shift angle, and the rotation stage itself is moved by the position shift distance to correct the distance. It is.
The multi-degree-of-freedom positioning stage of Patent Document 3 is configured so that the table 2 can be swiveled around the ball joint 4, and position correction by swiveling the table 2 is performed in the first to third slider mechanisms 10a to 10c. By adjusting the position of each thruster unit 11, the angles in the θx, θy, and θz directions are corrected.

Japanese Utility Model Publication No. 63-81291 JP-A-10-70177 Japanese Patent Laid-Open No. 11-114751

  Although the rotary stage of Patent Document 1 can correct the angular position with high accuracy, the detector 7 for detecting the rotation angle of the actuator 6 and the mounting table 1 is located outside the outer peripheral edge of the mounting table 1. These output ends and detection ends are in contact with protruding portions protruding outward from the mounting table 1. The structure of the device disclosed in Patent Document 1 is a principle, and this document does not disclose the technical idea that the rotary positioning stage is small and easy to use.

  The apparatus of Patent Document 2 requires a rotation mechanism for correcting the angle of the rotary stage 2 and a linear movement mechanism for correcting the distance, and has a complicated structure. Further, there is a description (paragraph 0047) that the groove cam 4 may be used for the linear moving mechanism and that the outer peripheral surface may be a plate cam. Is used for distance correction for linear movement, not for angle correction.

  The positioning stage 3 of Patent Document 3 is intended to three-dimensionally adjust the posture of a workpiece for performing polyhedral cutting and the posture of a target object such as a reflecting mirror and a tracking parabolic antenna, and has a complicated structure. In the assembly / inspection process, there is little need to adjust (swivel) the position of the table on which the workpiece is placed in order to correct the angle of the workpiece.

In addition, in the prior art, there is a rotating table that rotates 360 degrees. However, it is sufficient for the actual angle correction to be able to rotate about 10 degrees (angle rotation).
On the other hand, it is conceivable to directly drive the rotary table with a stepping motor, but since the stop angle error is large, it is not suitable for highly accurate positioning.

In any case, since the conventional rotary positioning stage has a complicated structure or has more functions than necessary, it often takes time to adjust and maintain the initial position. In addition, there are many protrusions around the rotary table, which often hinders assembly into an assembly line or inspection line.
It is an object of the present invention to provide a rotary positioning stage that has a simple structure and is capable of highly accurate angle correction, has few protrusions from the periphery of the rotary table, can have a small vertical dimension, and can be easily incorporated into a line.

A rotary table that is rotatably supported by the main body is rotated by a plate cam (angle feed). In this case, the plate cam is disposed between the rotary table and the main body so as to overlap them.
Further, the rotation axis of the rotary table and the rotation axis of the plate cam are arranged in parallel.
The plate cam may be rotated manually, but many use a stepping motor.
Usually, the rotary table is rotatably supported on the main body by a shaft, but may be rotatably supported on the main body at the peripheral edge.

  By using the plate cam for minute rotation of the rotary table, arranging the plate cam in a state of overlapping between the rotary table and the main body, and arranging the rotary axis of the rotary table and the rotary axis of the plate cam in parallel, A member for driving the rotary table rarely protrudes to the outside of the outer periphery of the rotary table, and in some cases, the drive mechanism can be stored in the area of the rotary table in plan view.

Since the plate cam having the outer periphery as the cam surface can be formed thin, the height of the rotary positioning stage can be compressed in combination with the fact that the plate cam is arranged so as to overlap between the rotary table and the main body.
The angle feed rotation of the rotary table can be set with high accuracy and easily by the lead of the cam curve in the plate cam and the contact distance between the rotary table and the plate cam from the rotation axis of the rotary table.
Since the cam has only to be rotated within 360 degrees, angle correction can be performed at a high speed of 0.1 second or less. Further, since the position adjustment is performed by the cam, positioning accuracy and repeatability are high.
The structure is simple and inexpensive, and the cam can be easily replaced and maintained.

  Example 1

  1 to 6 show a first embodiment, and the rotary positioning stage 1 includes a main body 2, a rotary table 3, a plate cam 4, and a stepping motor 5. The rotary table 3 is attached to the upper end of the shaft 6 with a screw 7 or the like, and the work mounting surface on the upper surface is attached to be orthogonal to the rotation axis 11 of the shaft 6, and the shaft 6 is rotatably supported by the main body 2 via a bearing 8. The The stepping motor 5 is attached to the main body 2 at the motor head portion with the axis 10 of the output shaft 9 parallel to the rotation axis 11 of the shaft, and the plate cam 4 is fixed horizontally to the upper end of the output shaft 9 with a set screw 12. The

The axis 10 of the output shaft 9 in the stepping motor 5 is disposed close to the rotation axis 11 of the rotary table 3, and the plate cam 4 is superposed on the lower surface side of the rotary table 3 in plan view as shown in FIG. 1.
The plate cam 4 is made of a steel plate having high rigidity even if it is thin, and the peripheral surface is a cam surface. The plate cam 4 can be combined with the mounting portion with the output shaft 9 by two screws as a component. A bearing may be provided between the plate cam 4 and the main body 2. The rotary table 3 includes a drive pin 13 and a spring pin 14 projecting from the lower surface. The drive pin 13 serves as a cam follower of the plate cam 4, and includes a roller 15 in contact with the peripheral surface of the plate cam 4 in the embodiment. In this embodiment, the drive pin 13 and the spring pin 14 are arranged at substantially the opposite positions across the rotation axis 11 of the turntable 3.

  The main body 2 includes a guide groove 17 that supports the shaft 6 and the stepping motor 5 and extends in the chord direction 16 (FIG. 1) of the rotary table 3 on a surface facing the lower surface of the rotary table 3. The guide groove 17 communicates with an insertion hole 18 formed horizontally in the chord direction 16 from the side surface of the main body 2. A lower part of the spring pin 14 on the lower surface of the rotary table 3 is fitted in the guide groove 17. On the other hand, a guide piece 19 and a coil spring 20 are loaded in the insertion hole 18, and the opening end is closed with a set screw 21. . The guide piece 19 is located between the coil spring 20 and the spring pin 14, and transmits the elasticity of the coil spring 20 to the rotary table 3. The biasing force of the coil spring 20 is a direction in which the driving pin 13 of the rotary table 3 is always brought into contact with and pressed against the cam circumferential surface of the plate cam 4.

  In this embodiment, the cam curve of the plate cam 4 is formed with a constant lead (hatched portion) in the range of 180 degrees from the initial position S (FIG. 6a) to the final position F with the output shaft 9 as the center. The distance from the center of 9 to the peripheral surface increases by a fixed amount (Δr) at a fixed angle. The plate cam 4 is reciprocally rotated, reversely rotates from the F position (solid line) in FIG. 6C, returns to the S position (chain line), and enters a standby state. Of course, it does not always rotate to the F position, but rotates only by an angle necessary for correcting the angle of the work placed on the rotary table 3, returns to the S position, and waits.

  The drive pin 13 is at a distance L from the rotation axis 11 of the turntable 3. Therefore, when the plate cam 4 rotates by a certain angle, the rotary table 3 rotates by about Δr / L radians. Therefore, the rotation accuracy of the turntable 3 can be adjusted by changing the values of Δr and L. Actually, when the stepping motor 5 rotates by one pulse, the turntable 3 rotates 0.05 degrees. Further, the rotation angle of the rotary table 3 corresponding to the cam allocation of 180 degrees is 12.5 degrees. It should be noted that a shaft provided between the plate cam 4 and the main body 2 can suppress the shaft shake of the output shaft 9 and achieve higher rotational accuracy.

6A, reference numeral 22 denotes a pin hole, which is a hole into which the cam end positioning pin 23 (FIG. 5) is inserted. The cam end positioning pin 23 inserted into the pin hole 22 is inserted into a main body side hole 24 provided at a predetermined portion of the main body 2. The position when the pin 23 is inserted is stored in the control device as a cam end.
In FIG. 2, reference numeral 25 denotes a dog, which is for detecting the rotational position of the rotary table 3 together with the photosensor 26 as shown in FIG. 3. In the illustrated example, the structure detects a range within about 10 degrees. It has become.

  The rotational positioning stage 1 (Embodiment 1) of this invention is used by being installed on an X / Y table. A workpiece such as an electronic component is placed on the upper surface of the turntable 3, the deviation of the angle of the workpiece is recognized by the image camera from above, the angle detected through the control device is compared with the determined angular position, and the deviation occurs. If necessary, correct the angle. That is, a specified number of pulses corresponding to the angle correction necessary for the stepping motor 5 is sent from the control device to the stepping motor 5, the plate cam 4 rotates by a corresponding specified amount, and the turntable 3 rotates via the drive pin 13. Thus, the angle correction of the workpiece is achieved. In the first embodiment, when the turntable 3 rotates counterclockwise, the coil spring 20 on the main body 2 side is compressed by the spring pin 14 that rotates at the same time, and when it rotates clockwise, it is returned by the elasticity of the coil spring 20. .

FIG. 7 shows a second embodiment of the present invention, which differs from the first embodiment in that the shaft 6 of the turntable 3 is cylindrical, but the other configurations are the same. That is, roughly, the plate cam 4 is used to drive the turntable 3, the plate cam 4 is arranged in a superposed state between the lower surface of the turntable 3 and the main body 2, and the rotation axis 11 of the turntable 3 and the plate cam. The axis 10 of the output shaft 9 of the stepping motor 5 for driving 4 is arranged in parallel and close to each other.
In the second embodiment, for example, when it is necessary to energize the work (handling control) placed on the rotary stage, the wiring is passed through the shaft 6, or the rotary table is used in the assembly / inspection line. It is necessary to monitor the position of the rotation axis 11, and this can be used when the inspection laser beam or the like reaches the upper detection device.

  As shown in the figure, the height of the main body can be reduced by shortening the shaft 6. For this reason, when the dog 25 or the photo sensor 26 (FIG. 2) cannot be arranged, for example, the body 2 is provided with a through-hole 27 that can monitor the lower surface of the turntable 3, and the transmission / reception sensor 28 is attached to the through hole 27. A position detection reflection line 28 a provided on the lower surface of the table 3 is detected.

  8 and 9 show a third embodiment, which differs from the first embodiment in that the rotary table 3 and the shaft 6 are integrally formed, but the other configurations are the same. That is, roughly, the plate cam 4 is used to drive the turntable 3, the plate cam 4 is arranged in a superposed state between the lower surface of the turntable 3 and the main body 2, and the rotation axis 11 of the turntable 3 and the plate cam. The axis 10 of the output shaft 9 of the stepping motor 5 for driving 4 is arranged in parallel and close to each other.

  Since the turntable 3 and the shaft 6 are integrally formed, the structure is simplified, and the number of assembling steps and adjustment processes are small. Further, if accuracy is taken at the time of molding, it is possible to prevent a situation in which a trouble occurs in the attachment of the rotary table 3 to the shaft 6 and the workpiece mounting surface is inclined when the rotary table 3 rotates.

FIGS. 10 and 11 show a fourth embodiment. In outline, the plate cam 4 is used to drive the rotary table 3, and the plate cam 4 is arranged in a superposed state between the lower surface of the rotary table 3 and the main body 2 and rotated. The rotation axis 11 of the table 3 and the axis 10 of the output shaft 9 of the stepping motor 5 for driving the plate cam 4 are arranged in parallel and close to each other.
In the fourth embodiment, the rotary table 3 does not include the shaft 6 and is supported by the main body 2 so as to be rotatable at a peripheral edge portion 29 thereof. Reference numeral 29 a is a bearing and is disposed between the lower surface of the peripheral edge portion 29 and the upper surface of the main body 2. The coil spring 20 in the first embodiment is a leaf spring 30 and is attached in a curved urging state between a spring pin 14 provided on the lower surface of the rotary table and a locking pin 31 provided on the main body 2. .
Other configurations are the same as those in the first embodiment.

The structure of the fourth embodiment has a wide space on the lower surface side of the turntable 3, and it is easy to fit both the plate cam 4 and the stepping motor 5 in the region of the turntable 3 in plan view as shown in the figure. . For this reason, the vertical and horizontal sizes in the plan view of the rotary positioning stage 1 can be made substantially equal to the diameter of the rotary table 3, and there are no protrusions to the periphery. It is easy to use with little interference with other devices. The
In the figure, in order to grasp the rotation position of the turntable 3, the dog 25 and the photo sensor 26 are arranged to be fitted on the lower surface side of the turntable 3, so that the rotary positioning stage 1 is configured compactly.

FIGS. 12 to 14 show a fifth embodiment. In summary, the plate cam 4 is used to drive the rotary table 3, and the plate cam 4 is arranged in a superposed state between the lower surface of the rotary table 3 and the main body 2. The rotation axis 11 of the turntable 3 and the axis 10 of the output shaft 9 of the stepping motor 5 for driving the plate cam 4 are arranged in parallel and close to each other.
In the fifth embodiment, the plate cam 4 is a double conjugate cam by reversing the cam plates 4a and 4b having the same cam curve as the plate cam 4 of the first embodiment. On the other hand, drive pins 13a and 13b are provided on the lower surface of the rotary table 3, and in contrast to the line connecting the rotary axis 11 of the rotary table 3 and the shaft 10 of the output shaft 9 of the stepping motor 5, both are cam plates. It arrange | positions in the position contact | abutted to the cam peripheral surface of 4a, 4b.

  When the cam plate 4 rotates, in the case of counterclockwise rotation, the cam plate 4a pushes the drive pin 13a to rotate the rotary table 3 counterclockwise. When the cam plate 4 rotates clockwise, the plate cam 4b presses the drive pin 13b to rotate the rotary table. 3 is rotated clockwise. However, the rotation angle of the turntable 3 is slightly smaller than that in the first embodiment. Since the rotation of the turntable 3 is restrained by the plate cams 4a and 4b in both the clockwise direction and the counterclockwise direction, in the first embodiment, the coil spring 20 for maintaining the contact between the drive pin 13 and the plate cam 4 The surrounding configuration is not required.

  FIGS. 15-17 is Example 6, and roughly uses the plate cam 4 for driving the rotary table 3, and the plate cam 4 is arranged in a superposed state between the lower surface of the rotary table 3 and the main body 2, The rotation axis 11 of the turntable 3 and the axis 10 of the output shaft 9 of the stepping motor 5 for driving the plate cam 4 are arranged in parallel and close to each other.

  In the sixth embodiment, in order to reduce the overall size of the rotary positioning stage 1, unnecessary portions of the rotary table 3 are deleted, and only necessary portions are left. Further, the spring pin 14 is provided so as to protrude from the shaft 6 to the side instead of the lower surface of the turntable 3. The shaft 6 is inserted into a guide groove 17 formed on the inner surface of the main body 2, and an insertion hole 18 is formed from another side surface of the main body 2 and communicates with the guide groove 17. As in the case of the first embodiment, a coil spring is press-fitted into the insertion hole 18 together with the guide piece, and the spring pin is always pressed.

  The embodiment has been described above. Although all of the embodiments use a stepping motor, it is also possible to use a servo motor. Further, the plate cam 4 can be structured so that it can be finely rotated manually.

Plan view (Example 1) Front view with cross section (hatch is omitted) Bottom view Right side view Front view showing part of stepping motor and plate cam (partial cross section) (hatching omitted) B, b, c are diagrams for explaining the plate cam and its operation Front view showing a part in cross section (Example 2) Plan view (Example 3) Front view in cross section (hatching is omitted) Plan view (Example 4) Front view in cross section Plan view (cam shows arrangement) (Example 5) Right side view Diagram for explaining structure and operation of conjugate cam Plan view (Example 6) Front view in cross section (hatching is omitted) Right side view

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rotation positioning stage 2 Main body 3 Rotary table 4 Plate cam 5 Stepping motor 6 Shaft 7 Screw 8 Bearing 9 Output shaft 10 Axis 11 Rotary axis 12 Set screw 13 Drive pin 14 Spring pin 15 Roller 16 String direction 17 Guide groove 18 Insertion hole 19 Guide piece 20 Coil spring 21 Set screw 22 Pin hole 23 Cam end positioning pin 24 Body side hole 25 Dog 26 Photo sensor 27 Through hole 28 Transmission / reception type sensor 28a Reflection line 29 Peripheral portion 29a Bearing 30 Leaf spring 31 Locking pin

Claims (10)

  A rotary table that is rotatably supported by the main body is rotated at an angle by a plate cam, and the plate cam is arranged between the rotary table and the main body so as to overlap with the rotary table, and the rotation axis of the rotary table A rotary positioning stage characterized in that the rotation axis of the plate cam is arranged in parallel.   The drive pin is fixed to the lower surface of the rotary table, and the drive pin is always in contact with the cam peripheral surface of the plate cam by the urging means provided between the rotary table and the main body. The rotational positioning stage according to 1.   The rotary table includes a shaft rotatably supported by the main body, a rotary table having a workpiece placement surface orthogonal to the rotation axis of the shaft on the upper end side of the shaft, a stepping motor and a plate cam fixed to the main body. A stepping motor is arranged on the lower surface side and its output shaft is arranged parallel to the shaft of the rotary table, and a plate cam is arranged on the lower surface side of the rotary table between the rotary table and the stepping motor. The drive pin is fixed to the shaft and fixed at a position on the lower surface of the rotary table that contacts the cam peripheral surface of the plate cam, while means for constantly urging the drive pin toward the plate cam is provided across the rotary table and the main body. Rotation positioning stage characterized by   The rotary positioning stage according to claim 3, wherein the shaft of the rotary table has a cylindrical shape, and the hollow portion penetrates to the mounting surface of the rotary table.   The rotary positioning stage according to claim 3 or 4, wherein the rotary table and the shaft are integrally formed.   A rotary table, a plate cam, and a stepping motor are provided, and the rotary table is rotatably supported by the main body at the periphery thereof. The stepping motor is arranged with an output shaft parallel to the rotation axis of the rotary table, and together with the plate cam in plan view The whole is housed in the plane view area of the rotary table, the plate cam is attached to the output shaft of the stepping motor, the drive pin provided on the lower surface of the rotary table abuts the cam peripheral surface of the plate cam, A rotary positioning stage characterized in that an urging means for constantly pressing the drive pin against the peripheral surface of the plate cam is provided.   The rotary positioning stage according to any one of claims 3 to 6, wherein a bearing is provided between the output shaft of the stepping motor and the main body.   The biasing means includes a coil spring loaded in a chord-direction groove of the rotary table formed on the upper surface of the main body and a spring pin fixed to the lower surface of the rotary table, and the spring pin is constantly pressed by the coil spring. The rotary positioning stage according to any one of claims 2 to 6.   The urging means includes a coil spring loaded in a chord-direction hole of the rotary table formed on the side surface of the main body and a spring pin protruding from the shaft of the rotary table, and the spring pin is constantly pressed by the coil spring. The rotational positioning stage according to claim 2, wherein:   A rotary table that is rotatably supported by the main body is rotated by an angle feed with a plate cam, and the plate cam is a conjugate cam that combines two sheets, with the rotary table and the main body overlapping with each other. A rotary positioning stage, characterized in that the rotary axis of the rotary table and the rotary axis of the plate cam are arranged parallel to each other.

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