JP2007189072A - Tray transport system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tray transport system for allowing works to be removed from a tray in an appropriate attitude. <P>SOLUTION: The system for placing a work on the tray 16 for transporting has an attitude correction apparatus 12 having detection means 32, 34 for detecting the attitude of the work in a horizontal surface, and correction means 30, 31 for correcting the attitude of the works, while traveling on the tray 16 based on the attitude detected. An opening 20 is provided at the bottom of the tray 16, a conveyor 14 that projects from the opening 20 and transports the work, while coming into contact with the bottom of the work is provided at the attitude calibration apparatus 12, and the correction means 30, 31 move the tray 16 within the range of clearances D1, D2 between the opening and the conveyor 14. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a system for placing a workpiece on a tray and transporting it, and more particularly to enabling the workpiece to be taken out from the tray in a correct posture.

The applicant is considering placing a work such as a substrate of a liquid crystal panel or an EL panel, a semiconductor wafer, etc. on a tray for conveyance. Patent Document 1 proposed a tray structure in which workpieces can be taken in and out, and Patent Document 2 proposed a stacking / stacking device in which trays can be stacked and cut out. By the way, when the work is taken out from the tray and supplied to the processing apparatus, the posture of the work needs to be adjusted. Since substrates such as liquid crystal panels and EL panels are thin and have a very large horizontal plane size, it is difficult to change the posture.
JP 2005-93585 A JP 2005-89048 A

An object of the present invention is to easily correct the posture of a workpiece without placing a burden on the workpiece.
An additional problem in the invention of claim 2 is to prevent the tray protruding from the opening at the bottom of the tray and the tray from interfering with each other by correcting the posture of the workpiece.
An additional problem in the invention of claim 3 is to easily change the posture of the tray that has been stacked and stored, and then enable stack storage again.

  According to the present invention, in a system in which a workpiece is placed on a tray and conveyed, a detecting means for detecting the posture of the workpiece in a horizontal plane, and the posture of the workpiece is corrected by moving the tray based on the detected posture. And a posture correction device provided with a correction means.

  Preferably, an opening is provided in the bottom of the tray, and a posture conveyor is provided in the posture correcting device so as to protrude from the opening and contact the bottom surface of the work, and the correcting means is a tray within a clearance between the opening and the conveyor. To move.

  More preferably, a stacking device that cuts trays from trays that are stacked and stored on the upstream side of the posture correction device is provided, and a stacking device that stacks trays on the downstream side is provided. After that, the posture of the tray is returned to a predetermined posture.

  In the present invention, when the posture of the workpiece in the horizontal plane is detected, the posture of the workpiece is corrected by moving the tray, so that the posture can be corrected without applying a load to the workpiece. And thereby, a workpiece | work can be taken out from a tray with a correct attitude | position.

  In the invention of claim 2, since the tray is moved within the clearance between the opening at the bottom of the tray and the conveyor, the conveyor and the tray do not interfere with each other. For this reason, even when a conveyor is protruded from an opening provided in the bottom of the tray and the workpiece is taken in and out, the posture of the workpiece can be easily corrected.

  In the invention of claim 3, a stacking device is provided on the upstream side of the posture correcting device, and a stacking device is provided on the downstream side, and the trays are respectively stacked and stored. Here, the posture of the workpiece is corrected by moving the tray taken out from the separating device, and the empty tray from which the workpiece has been taken out is corrected to the correct posture by the same posture correcting device. Thereafter, when the work is placed on the tray and moved to the stacking device, the tray is aligned in the stacking device. One posture correcting device can be used for both correcting the posture of the workpiece and correcting the posture of the empty tray from which the workpiece is taken out.

  In the following, an optimum embodiment for carrying out the present invention will be shown.

  The tray conveyance system 2 of an Example is shown in FIGS. The tray transfer system 2 is provided in a clean room, and transfers a workpiece such as a liquid crystal panel substrate, an EL panel substrate, or a semiconductor wafer to the processing apparatus 4. Reference numeral 6 denotes a tray conveyor, which transports workpieces in units of trays. Reference numeral 8 denotes a leveling device, which cuts out a required tray from the stacked and stored trays and supplies it to the workpiece posture correcting device 12. A stacking device 10 stacks the trays conveyed from the workpiece posture correcting device 12. In addition, on the upstream side of the stacking device 8 and the downstream side of the stacking device 10, single-sheet conveyance in units of trays or stacked conveyance in which trays are stacked may be performed. A work conveyor 14 moves the work between the work posture correcting device 12 and the processing device 4.

  FIG. 2 shows the principle of posture correction of the workpiece 18. Reference numeral 16 denotes a tray, and reference numeral 17 denotes a take-out port provided on the side surface thereof, which is used for taking in and out the work 18. There is another opening 20 shown in FIG. 3 at the bottom of the tray 16. An appropriate sensor such as an optical camera or an ultrasonic sensor is used to detect the positions of the three points P1 to P3 on the side of the workpiece 18 or the two vertices of the workpiece 18. For example, as shown in FIG. 2, it is assumed that two points P1 and P2 are detected on one side of the work 18 and P3 is detected on the other side. Since one side of the workpiece 18 passes through the points P1 and P2, the first vertex V1 is obtained by dropping a perpendicular foot from the point P3 to this straight line. A position advanced on the straight line V1-P3 by the length of the side of the workpiece 18 from the vertex V1 is defined as a second vertex V2. Further, a position that is advanced from the vertex V1 by the length of the side of the workpiece 18 on the straight line passing through the points P1 and P2 is defined as a third vertex V3. When the vertices V1, V2, and V3 are obtained, the last vertex V4 is also obtained.

  Further, even if one point is detected on each of three different sides of the work 18, the positions of the four vertices of the work 18 can be similarly determined. However, this process is complicated in calculation. Further, instead of detecting the three points on the side of the workpiece 18, the positions of the two vertices may be detected, but the detection is difficult.

  When the positions of the four vertices V1 to V4 of the workpiece 18 are obtained, an error in the posture of the workpiece 18 from the normal posture is obtained. The direction when the workpiece 18 is taken out from the tray 16 is defined as the x direction, the conveyance direction of the tray 16 is defined as the y direction in a direction perpendicular thereto, and the direction from the x axis is defined as the angle θ. In posture correction, there are a y-direction position of the center of gravity of the workpiece 18 and a direction in the θ direction, both of which are postures in a horizontal plane. In the embodiment, as the posture correction, the y-direction position and the orientation in the θ direction are corrected, but at least the orientation in the θ direction may be corrected.

  When the posture of the workpiece 18 is detected, the tray 16 is moved in the opposite direction by the same movement amount so as to correct the posture. Next, when the workpiece 18 is taken out from the tray 16, the workpiece 18 can be taken out in a correct posture. Here, since the workpiece 18 itself is not directly operated, the posture can be easily corrected even with a thin and large liquid crystal panel or EL panel substrate without applying a load to the workpiece.

  FIG. 3 shows the structure of the workpiece posture correcting device 12. Here, for the sake of simplicity, the workpiece is not placed on the tray 16 is shown. The bottom of the tray 16 has a plurality of openings 20 and a plurality of pins 22, and the pins 22 support the bottom surface of the workpiece. The posture correcting device 12 is provided with an elevating conveyor 24 that can be raised and lowered so as to protrude from the opening 20, and its drive member is a roller 26, but a short roller or the like may be used. Then, the work is moved in the x direction of FIG. Here, as enlarged and shown in the lower right of FIG. 3, the clearance between the end of the opening 20 and the roller 26 is defined as D1 and D2.

  Reference numeral 28 denotes an elevating member, which is provided with a cylinder 30 that does not interfere with the tray 16 when raised and contacts the side surface of the tray 16 with a roller 31 or the like when lowered. As a result, the roller 31 moves back and forth toward the tray 16 due to air pressure and the like, and the roller 31 moves forward and backward independently for each cylinder 30, so that the posture of the tray 16 can be corrected within a range of, for example, several millimeters. Reference numeral 32 denotes a camera that captures an image of the side of the work, and the posture detection unit 34 recognizes the image of the camera 32 to obtain a point on the side, and then obtains the coordinates of the four vertices of the work as shown in FIG. . The content of the processing of the posture detection unit 34 and the way of taking coordinates for indicating the posture of the workpiece are arbitrary. The controller 36 moves the tray 16 in the reverse direction so as to cancel the error in the posture of the workpiece from the normal posture by lowering the elevating member 28 based on the signal from the posture detector 34 and controlling the cylinder 30. In the posture change of the tray 16, for example, the movement amounts of the four vertices of the tray 16 are set to be less than or equal to the clearances D1 and D2. In this way, the edge of the opening of the tray 16 does not interfere with the rollers 26 of the lifting conveyor 24.

  When the correction of the posture of the tray 16 is completed, the elevating conveyor 24 is raised and the work is lifted up by the rollers 26, and then moved to the right side in FIG. 3 and taken out to the work conveyor 14. Next, for example, after the elevating conveyor 24 is lowered, the tray 16 is returned to the original posture using the cylinder 30. For example, when the workpiece is received from the workpiece conveyor 14 at the same position, the workpiece is correctly positioned with respect to the tray 16. To be accepted. However, the work may be received on the tray 16 at a position different from that of the work posture correcting device 12.

  Here, the work is carried out from the tray 16 by the roller 26. However, when taking out the work from the tray 16, conveyance by airflow or floating conveyance may be used. Furthermore, although the four cylinders 30 are used for controlling the posture of the tray 16, a ring-shaped turntable or the like may be provided on the outside of the elevating conveyor 24 instead.

  FIG. 4 shows the structure of the stacking device 8 used in the embodiment, which is also common to the stacking device 10. Reference numeral 40 denotes a pantograph that raises and lowers the tray group 49, and 42 denotes a chuck that supports the lower portion of the tray group 48. A tray cut out from the stacked tray group is cut out by a conveyor 44 that can be moved out and with a cylinder 45. In the embodiment, the tray posture is the same in both the stacking device 8 and the stacking device 10, the tray 16 is moved by the workpiece posture correcting device 12, and the tray posture is returned to the original by the same workpiece posture correcting device 12.

In the embodiment, the following effects can be obtained.
(1) The workpiece can be removed from the tray in the correct posture without applying stress to the workpiece.
(2) The tray posture control does not interfere with the lifting conveyor 24 for picking up workpieces.
(3) The workpiece posture correcting device 12 can be used both for tray posture control before removing the workpiece and for returning the tray posture. For this reason, in the stacking device 8 and the stacking device 10, the posture of the tray 16 can be aligned.

The top view which shows typically the layout of the tray conveyance system of an Example The figure which shows typically from the attitude | position detection of a workpiece | work to the attitude correction of a tray in an Example. Plan view of main part of posture correcting device for workpiece in embodiment Side view of the stacking / stacking device in the embodiment

Explanation of symbols

2 Tray Conveying System 4 Processing Device 6 Tray Conveyor 8 Stacking Device 10 Stacking Device 12 Work Posture Correction Device 14 Work Conveyor 16 Tray 17 Taking Out Port 18 Work 20 Opening 22 Pin 24 Lifting Conveyor 26 Roller 28 Lifting Member 30 Cylinder 31 Roller 32 Camera 34 Attitude detection unit 36 Controller 40 Pantograph 42 Chuck 44 Conveyor 45 Cylinder 46 Frame 48, 49 Tray group

P1 to P3 Points on the side of the workpiece V1 to V4 Vertex of the workpiece D1 to D2 Clearance

Claims (3)

In a system that loads and transports workpieces on a tray,
A posture correcting device including a detecting means for detecting a posture of a workpiece in a horizontal plane and a correcting means for correcting the posture of the workpiece by moving a tray based on the detected posture is provided. Tray transport system. In addition to providing an opening at the bottom of the tray, the posture correcting device is provided with a conveyor that protrudes from the opening and contacts the bottom surface of the workpiece and conveys the tray, and the correcting means moves the tray within the clearance between the opening and the conveyor. The tray conveyance system according to claim 1. A stacking device for stacking trays on the downstream side, and a stacking device for stacking trays on the downstream side are provided on the upstream side of the posture correction device.
The tray conveyance system according to claim 2, wherein the posture of the tray is returned to a predetermined posture after the workpiece is carried out of the tray by the conveyor by the posture correction device.

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