JPH05228796A - Positioning control device - Google Patents

Abstract

(57) [Abstract] [Purpose] An inexpensive induction motor is used as a power source and ON / OFF control is performed to enable highly accurate positioning. [Structure] A cross section D is formed on the rotary shaft 4 of the induction motor 1.
A character-shaped power transmission unit 5 is provided. A cylindrical portion 7 into which the power transmission portion 5 is inserted is provided at the center of the upper surface of a rotary table 2 arranged coaxially with the motor 1, and a rotation transmission member 8 is radially driven into the cylindrical portion 7 to form an inner end portion. Are opposed to the flat surface portion of the power transmission unit 5. Rotating shaft 4 by driving motor 1
When is rotated, the rotation transmitting member 8 abuts and engages with the flat surface portion to transmit the rotation of the rotary shaft 4 to the rotary table 2. When the rotary table 2 rotates and approaches the position to be positioned, the motor 1 is stopped. Even if the motor 1 itself stops, the rotary table 2 and the rotary shaft 4 further rotate by a certain angle due to inertial force and stop, and when the rotary table 2 stops, the roller 15a of the micro switch 15 causes the roller 15a of the peripheral surface of the rotary table 2 to rotate. The spring 1 is provided in the notch 13 or 14 formed in
The rotary table 2 is positioned by being depressed by the force of 5c.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positioning control device for positioning a driven body with high precision by using an induction motor.

[0002]

2. Description of the Related Art In each industrial field, low price and high quality products are desired. For this reason, automation and labor saving have been attempted in order to improve the efficiency of processing and assembly work or to stabilize quality and performance. High positioning accuracy is required as one of the most important items for automation and labor saving. Since this positioning control can perform highly accurate positioning control, a servo motor (accuracy ± 0.36 °) or a stepping motor (accuracy ± 0.08 °) using a pulse signal is used. Mainstream. However, since these motors have other functions such as high-speed movement and continuous control, there is a problem that the cost becomes high when these functions are not required. Therefore, in a positioning control device that does not require high-speed movement or continuous control, development of a device that can perform high positioning control using an inexpensive induction motor is desired.

[0003]

However, although the induction motor is inexpensive, the control by only ON and OFF can obtain an accuracy of about ± 5 ° even if the inertial force is taken into consideration. There is a problem in that it cannot be used as it is as a drive source for an apparatus that requires high-precision positioning accuracy such as a relation.

Therefore, the present invention has been made in view of the above-mentioned problems and demands of the related art, and an object of the present invention is to use an inexpensive induction motor as a power source and perform ON / OFF control thereof. Accordingly, it is an object of the present invention to provide a positioning control device capable of performing highly accurate positioning.

[0005]

In order to achieve the above object, the present invention provides an induction motor having a rotary shaft having a power transmission portion having a flat surface portion and having a D-shaped cross section, and a cutout portion on the peripheral surface. A driven body disposed coaxially with the rotating shaft, a rotation transmitting member that abuts and engages with the flat surface portion when the induction motor is driven, and transmits the rotation of the rotating shaft to the driven body; A positioning member disposed corresponding to the cutout portion of the body, wherein the rotation transmitting member sets the driven body to an unloaded state when the rotation transmitting member is not in abutting engagement with the flat surface portion, and the driven body is in position. After the energization of the induction motor is stopped before the position to be determined, the induction motor is still rotated by a certain angle and stopped, and the positioning member is positioned by engaging with the notch.

[0006]

In the present invention, the rotation transmitting member is provided integrally with the driven body and abuts and engages with the flat surface portion of the power transmitting portion provided on the rotating shaft when the induction motor is driven, whereby The rotation is transmitted to the driven body. When the motor rotates to a position just before the position where the driven body should be positioned, the power supply is cut off and the motor stops, but the driven body still rotates by a certain angle and stops. When the driven body stops, the positioning member engages with the cutout portion of the rotary table to position the driven body.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the embodiments shown in the drawings. FIG. 1 is an external perspective view showing an embodiment of a positioning control device according to the present invention, and FIG. 2 is a plan view of a rotation shaft and a rotation transmission member. In these drawings, 1 is an induction motor (hereinafter simply referred to as a motor) as a drive source, and 2 is a rotary table as a driven body whose position is controlled by the motor 1. The motor 1 is integrally provided with a gear box 3 and is vertically installed on the device fixing portion side with the rotating shaft 4 facing upward. The rotating shaft 4 has a cross section D at the upper end.
It has a character-shaped power transmission unit 5. The turntable 2 is
A cylindrical portion 7 having a central hole 6 into which the rotary shaft 4 is loosely inserted is provided integrally with the motor 1 so as to be rotatably supported coaxially with the motor 1 at the center of the upper surface thereof. Further, a rotation transmitting member 8 is radially driven into the peripheral surface of the cylindrical portion 7 so as to correspond to the flat surface portion 5a of the power transmitting portion 5 of the rotary shaft 4. The rotation transmitting member 8 has a cylindrical portion 7 at the inner end.
When the rotation shaft 4 rotates in the direction indicated by the arrow in FIG. 2, the rotation shaft 4 comes into contact with and engages with a point P of the rotation-side end of the flat surface portion 5a, thereby rotating the rotation shaft 4 to the rotation table 2. Is configured to communicate. The rotary table 2 has two recesses 11 and 12 of the same shape.
And notches 13 and 14 are provided. Recesses 11, 1
2 has a phase difference of 180 ° on the surface of the rotary table 2,
In other words, the rotary table 2 (rotary shaft 4) is recessed at symmetrical positions with the center 0 interposed therebetween, and the rotary table 2 is
Each time it is rotated by 80 °, it is moved alternately to the board setting position A and the soldering position B, and a printed circuit board on which, for example, an electronic component is mounted is set at the board setting position A, and when it moves to the soldering position B, the soldering of the electronic component It is supposed to be attached. In this case, the recesses 11 and 12 are formed with high precision (± 0.05 mm) so that the centers of these recesses are exactly aligned with an arbitrary straight line L passing through the center 0 of the rotary table 2. The notches 13 and 14 are provided on the rotary table 2.
Similarly, it is formed so as to be located on a straight line orthogonal to the straight line L ₁ with a phase difference of 180 °.

Reference numeral 15 denotes a micro switch as a positioning member provided on the outer side of the rotary table 2. The micro switch 15 has a positioning point C provided on the outer side of the rotary table 2 as shown in FIG. The rotary table 2 is positioned and stopped so that the centers of the recesses 11 and 12 are correctly positioned on the straight line L ₂ connecting the position A and the solder position B. When the rotary table 2 is correctly positioned, the roller 15a is notched. Since it falls into the portion 13 (or 14) and separates from the movable contact 15b, the roller 15a is held in the OFF state, and the roller 15a is notched 13 (or 14).
When the movable contact 1 is withdrawn from the movable table 1 and is pressed against the outer peripheral surface of the rotary table 2 by the force of the spring 15c.
It is configured to return to the ON state in order to press 5b. Then, the soldering is controlled by the signal of the micro switch 15. 16 is the cutouts 13 and 14
Is a sensor for detecting.

Next, the positioning operation of the rotary table 2 by the positioning control device having such a configuration will be described. FIG. 2 is a diagram showing a positional relationship between the power transmission portion 5 of the rotary shaft 4 and the rotation transmission member 8 when the rotary table 2 is not positioned when the motor is stopped. Rotation transmission member 8
Holds the rotary table 2 in an unloaded state when the rotary table 2 is not in abutting engagement with the flat surface portion 5a of the power transmission portion 5. When the motor 1 is driven from this state, the rotary shaft 4 starts to rotate clockwise in FIG. 2, and when it rotates by a certain angle, a point P of the rotary side end of the flat surface portion 5a comes into contact with the inner end of the rotation transmitting member 8. The rotation of the rotary shaft 4 is transmitted to the rotary table 2 through the rotation transmission member 8 because the rotation shaft 4 is engaged (see FIG. 3) and presses it. Therefore, the rotary table 2 starts to rotate integrally with the rotary shaft 4. When the rotary table 2 starts to rotate and approaches the position where it should be positioned, the sensor 16 detects the notch 14 (or 13), and the detection signal turns off the power to stop the motor 1. Even when the power of the motor 1 is turned off, the rotary table 2 and the rotary shaft 4 do not immediately stop but rotate by an angle due to the inertial force, but the rotary shaft 4 with a small inertial force first stops and then the rotation with a large inertial force. Table 2 stops. That is, as shown in FIG. 4, the rotation table 2 has an angle until the rotation transmitting member 8 is separated from a point P of the rotation side end of the flat surface portion 5a and abuts and engages with a point Q of the counter rotation side end. It has a play by θ and is allowed to rotate within this angle range regardless of the rotation axis 4. Then, the stop position of the rotary table 2 is adjusted to a position immediately before the rotation transmitting member 8 comes into contact with and engages with the one point Q of the counter-rotation side end portion, thereby obtaining an accuracy of ± 5 °. Such adjustment of the stop position can be easily determined by the inertial force of the rotary table 2 and the rotary shaft 4 and the play angle θ. The stop position is such that the notch 13 (or 14) is slightly on the front side of the roller 15a of the micro switch 15, and a part of the peripheral surface of the roller 15a faces the notch 13. Therefore, when the rotary table 2 stops and the cutout portion 13 and the roller 15a substantially coincide with each other, the roller 15a falls into the cutout portion 13 only by the force of the spring 15c to stop the rotary table 2 at the positioning position. High (± 0.8 °) positioning is possible. At this time, the rotary table 2 is rotated by a slight angle due to the roller 15a falling into the cutout portion 13. This rotation causes the rotation transmission member 8 to move to a point Q at the counter rotation side end portion at the stop position of the rotary table 2 as described above. This is possible because the position is adjusted to the position immediately before contacting and engaging with.

When the frictional force between the rotary table 2 and the rotary shaft 4 is large, it is desirable to interpose a bearing between them. Further, although the micro switch is used as the positioning member 15 in the above-described embodiment, it is needless to say that a leaf spring or the like may be used instead of this.

[0011]

As described above, the positioning control device according to the present invention drives the driven part by an inexpensive induction motor, turns off the motor power before the position to be positioned, and uses the inertial force to rotate the rotary shaft of the motor. Since the driven body is rotated by a required angle to stop immediately before the position to be positioned, and the subsequent positioning is mechanically performed using the positioning member, an expensive pulse motor,
It is possible to provide a much cheaper control device than a conventional positioning control device using a servo motor or the like.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a positioning control device according to the present invention.

FIG. 2 is a plan view of a rotation shaft and a rotation transmission member.

FIG. 3 is a diagram showing a state in which a rotary table and a rotary shaft are rotating.

FIG. 4 is a view showing a play of a rotary table.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 induction motor 2 rotary table 4 rotary shaft 5 power transmission part 5a flat surface part 8 rotation transmission member 11, 12 recessed part 13, 14 cutout part 15 micro switch 15a roller 16 sensor

Claims (1)

[Claims] 1. An induction motor having a D-shaped power transmission section having a flat surface portion on a rotary shaft, and a driven body coaxial with the rotary shaft having a cutout portion on a peripheral surface thereof. A rotation transmitting member that abuts and engages with the flat surface portion when the induction motor is driven to transmit the rotation of the rotating shaft to the driven body, and a positioning member disposed corresponding to the cutout portion of the driven body. The driven member is in an unloaded state when the rotation transmitting member is not in abutting engagement with the flat surface portion, and the energization of the induction motor is stopped before the driven member is positioned. The positioning control device is characterized in that after being rotated, it is rotated by a certain angle due to inertial force and stopped, and the positioning member is positioned by engaging with the notch.