JPH064228B2 - Origin detection device for transfer equipment - Google Patents

Description

The present invention relates to an automatic transfer device for grabbing a component in accordance with, for example, a predetermined program and shifting it from one point to another, and more particularly to an origin detection device of the same device. . In other words, in the operation of this type of transfer device, since the predetermined movement position is controlled with respect to the origin serving as the predetermined reference point, the operation is performed from the state where the origin is confirmed and the device is set prior to the start of the operation. Do not be afraid to start.

Since the origin device of the transfer device needs to be set at an arbitrary position of the transfer device, it is not possible to provide a stopping means such as a stopper.
Further, since both sides of the origin are the moving ranges, it is necessary to search the origin regardless of whether the transfer device approaches from one side of the origin or approaches from the other side.

In the above search of the origin, when operating the whole area at a speed that can be stopped immediately, it is not necessary to reduce the speed of the transfer device near the origin, but from one or the other side to the vicinity of the origin for time reduction. A detector that detects that the transfer device is approaching and decelerates from a normal speed to a speed at which it can be stopped immediately is required.

In a transfer device that requires a positioning accuracy of 5/100 mm or higher, the origin position is the reference point, so
For example, it needs to be repeatedly determined with high accuracy within 2/100 mm. Therefore, the origin position needs to be a position where signals of both the origin detector and the reference angular position of the encoder attached to the rear portion of the servo motor for operating the transfer device can be obtained at the same time.

That is, since the encoder of the servo motor has a structure in which a signal indicating that the reference angular position is the high-precision one position per one rotation of the motor shaft is output, the detection range of the origin detector attached to the transfer device is limited. When the servomotor makes one rotation and the movement amount is smaller than the movement amount of the transfer device, only one position can simultaneously obtain signals of both the origin detector and the reference position of the servomotor.

Next, the origin detection device of the conventional transfer device will be described below.

FIG. 6 shows an example of the origin detecting device of the conventional transfer device which uses three detectors. The detectors A and C obtain signals for decelerating the moving body 50. The container B detects the origin.

When the moving body 50 approaches from the left, the detector A decelerates and stops at the position where the signal of the detector B and the signal of the reference point of the encoder of the servo motor for operating the moving body 50 are obtained at the same time. When the moving body 50 approaches from the right, the detector C decelerates and the detector B stops as in the above. In the figure, W is the length of the detection target plate 51 attached to the moving body 50, and is smaller than the amount of movement of the moving body 50 by one rotation of the servo motor. Further, W'in the figure is an amount required to decelerate the moving body 50 to a speed at which it can be stopped immediately. In this conventional example, when the moving body 50 is located only in one direction to the right or left of the origin, the detectors A or C are unnecessary and may be two.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an origin detecting device for a transfer device that reduces the number of detectors that normally required three detectors from two to two.

The present invention will be described below with reference to the drawings showing an embodiment thereof.

Reference numeral 1 is a board, and a fixing bracket 2 is fixed on the board 1.
The X direction slide shaft 3 is supported by the fixed bracket 2, and the X table 4 is movably supported by the X direction slide shaft 3. 5 is X table 4
The X table 4 is guided by the Y-direction slide shaft 3 in the direction of the arrow X (X direction) by a motor contained therein to move. Note that 3a is a stopper attached to both ends of the X-direction slide shaft.

A fixed bracket 6 is fixed on the X table 4,
A Y-direction slide shaft 7 is supported on the fixed bracket 6, and a Y-table 8 is movably supported on the Y-direction slide shaft 7. 9 is the Y table 8
The Y table 8 moves in the direction of the arrow Y (Y direction) by being guided by the Y direction slide shaft 7 by the motor contained therein. That is,
As shown in FIG. 3, fixed blocks 10 and 11 are fixed to the inside of the motor housing portion 9 on the X table 4, the DC motor 1 and the encoder (pulse generator) 13 are attached, and the CD motor 12 is provided. A ball screw 14 connected to the rotary shaft of is supported by the fixed blocks 10 and 11. On the other hand, a mounting member 15 is attached to the inside of the Y table 8, a ball screw nut 6 is fitted to the mounting member 15, and a ball screw nut 16 is screwed onto the ball screw 14. A slide guide 17 is formed on the mounting member 15, and the slide guide 17 is slidably fitted on the Y-direction slide shaft 7. Therefore, when the DC motor 12 rotates normally or reversely, the Y table 8 moves in the direction of the arrow Y by the screw engagement of the ball screw 14 and the ball screw nut 16, and the moving distance is controlled based on the pulse signal of the encoder 13. It 7a is a stopper attached to both ends of the Y-direction slide shaft,
The inside of the motor housing 5 is the same as the inside of the motor housing 9.

Further, an upper and lower cylinder 19 is supported on the Y table 8 via a stand 18, and a chuck 20 for grasping, for example, a component is attached to the lower end of the upper and lower cylinder 19. Therefore, by moving the X table and the Y table while controlling them as described above, the chuck 20 can move the component from one predetermined position to another predetermined position. If the chuck 20 is used as a grease supply section, the grease can be supplied to a predetermined position while controlling the X table and the Y table.

Here, position detection units 21 and 22 are provided for the X table 4 and the Y table 8, respectively. Position detector 2
Since the structures of 1 and 22 are basically the same, the position detecting section 21 for the X table 4 will be described in detail with reference to FIGS. 4 and 5. A detector rail 23 is fixed to the substrate 1. Numerals 24 and 25 are optoelectronic counter type origin detectors, which are fixed to the detector rail 23 by a bolt 27 via a mounting member 26 so as to be positionally adjustable. Reference numeral 28 is a photoelectric counter type limit detector, and a bolt 30 via a mounting member 29.
The position is fixed to the detector rail 23 by means of. The origin detectors 24, 25 and the limit detector 28 have grooves 24a, 25a, 28a, respectively.
25a, 28a sandwiched between the light projecting portions 24b, 25b, 28
b and the light receiving portions 24c, 25c, 28c face each other. Three
Reference numeral 1 denotes a plate to be detected formed of an iron plate, which is fixed to the side surface of the X table 4 and passes through the grooves 24a, 25a and 28a of the origin detectors 24 and 25 and the limit detector 28 in the arrow Z direction. .

Next, the operation of the position detector 21 will be described with reference to FIG. When the DC motor rotates, the ball screw rotates, and the X table 4 moves in the direction of arrow p in FIG. 5 (a), the plate 31 to be detected moves in the direction of arrow p and approaches the origin detector 25 to move its groove. Upon entering 25a, the origin detector 25 detects this and reduces the rotation speed of the DC motor to reduce the moving speed of the X table 4. When the plate 31 to be detected further reaches the origin detector 24, the origin detector 24 detects this and stops the DC motor to stop the X table 4 at the origin. When the X table 4 moves in one direction, the plate 31 to be detected reaches the limit detector 28, and the limit detector 28 detects this and stops or reverses the DC motor, so that the X table 4 reaches the limit. Prevent movement in one direction over. As shown in FIG. 5 (c), when the X table 4 and the detected plate 31 approach the origin detectors 24 and 25 in the direction of arrow Q, the detected plate 31
When it reaches the origin detector 24, the origin detector 24 detects this and reduces the rotation speed of the DC motor to reduce the moving speed of the X table 4. Further, the detected plate 31
When reaches the origin detector 25, the origin detector 25 detects this and stops the DC motor and stops the X table 4 at the origin. In the above embodiment, D
One rotation of the C motor rotates the ball screw once, and the 5 mm detected plate 31 corresponding to one lead of the ball screw moves. Further, as shown in FIG. 5 (b), the gap W'between the centers of the origin detectors 24 and 25 is set to a dimension of 10 mm required for slowing corresponding to two revolutions of the DC motor, and the plate 31 to be detected is Width W
Is 15 mm.

In the above configuration, the width W of the detected plate 31 and the origin detector 2
By setting the difference in the gap W ′ between the centers of 4 and 25 as the movement amount of one rotation of the ball screw, the position of the origin detectors 24 and 25 can be adjusted to any position, and the detected object can be detected from either the right or left direction. Even if the plate 31 approaches, the origin detectors 24, 25
There is always only one position for detecting the origin of the encoder of the DC motor, which is the origin of the apparatus.

In the above embodiment, the two origin detectors are fixed by one mounting member, but they are different mounting members and adjusted to a predetermined interval.
May be attached. In addition, although the detector is a photoelectric type in the embodiments, other detectors such as a Hall element and a lid switch may be used.

As is clear from the above embodiment, the origin detection device of the present invention has a substrate and a table that move relative to each other by the rotation of a servomotor equipped with a detection means for detecting the rotational angle position. One of the two origin detectors is a pair of origin detectors that can change the position in the direction of relative movement between the substrate and the table and can be used to obtain a command to decrease the rotation speed of the servo motor and a command to stop the servo motor, respectively. In the moving speed of the substrate or the table, the moving speed of the substrate or the table is provided at an interval corresponding to the moving distance of the substrate or the table required to stop the rotation speed of the servo motor, and the other of the substrate or the table is It is longer than the above-mentioned two origin detectors can work at the same time. A detection member having a length shorter than a length obtained by adding the movement length of the substrate or the table moved by one rotation of the servo motor, and a control means for decelerating / stopping the servo motor by the origin detector. A limit detector for detecting the limit of the relative movement range between the substrate and the table is provided. By providing two origin detectors, the origin detector can be adjusted to any position and Whichever direction is approaching the origin detector, the member to be detected reaches immediately before the origin, the first origin detector is actuated to decelerate the table, and finally the first and second The second origin detector can work together to detect a predetermined origin and stop the table at the origin. At this time, since the detection range of the origin detector is smaller than the movement amount of the table when the servo motor makes one rotation, both signals of the origin detector and the reference position during one rotation of the servo motor are simultaneously detected. Only one position can be obtained, and high origin accuracy can be obtained. Further, the change of the origin can be easily performed by moving and adjusting the origin.

[Brief description of drawings]

1 is a perspective view of a transfer device equipped with the origin detection device of the present invention, FIG. 2 is a perspective view of the origin detection device, and FIG. 3 is a partially cutaway perspective view of the origin detection device. Is a perspective view of the main part of the origin detection device, FIGS. 5 (a), (b), and (c) are operation explanatory views of the origin detection device, and FIG. 6 is an operation description of the origin detection device of the conventional moving device. It is a figure. 1 ... Substrate, 4 ... X table, 8 ... Y
Table, 12 ... DC motor (motor), 14 ... Ball screw, 16 ... Ball screw nut, 21, 22 ... Position detector, 24, 25 ... Origin detector, 28 ... Limit Detector, 31 ... Plate to be detected.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-50-98056 (JP, A) JP-A-53-22255 (JP, A) JP-A-54-93553 (JP, A)

Claims (1)

[Claims] 1. A substrate and a table which move relative to each other by the rotation of a servomotor equipped with a detecting means for detecting a rotational angle position, and the relative motion of the substrate and the table on one of the substrate and the table. A pair of origin detectors for changing the direction of the servo motor and for obtaining a command to decrease the rotation speed of the servo motor and a command to stop the servo motor, respectively, at the moving speed of the substrate or the table. The substrate or table is provided with a distance required for moving the servo motor from the lowering speed to the stopping, and the two origin detectors are simultaneously provided on the other side of the substrate or table. It is longer than the length that can be actuated by one rotation of the servo motor to the length that can act two origin detectors at the same time. A detection target member having a length shorter than the sum of the moving lengths of the moving substrate or table is provided, and the control means for decelerating and stopping the servomotor by the origin detector and the relative movement range of the substrate and table are set. An origin detection device for a multiple mounting device, which is provided with a limit detector for detecting the limit.