JP5969238B2 - How to determine the presence or absence of a plate workpiece - Google Patents

Description

  The present invention relates to a method for determining the presence or absence of a plate-like workpiece in a conveyance unit that conveys the plate-like workpiece.

  A transport robot that transports a plate-shaped workpiece includes a robot hand that sucks and holds the plate-shaped workpiece. The robot hand can suck and hold the plate-shaped workpiece and transport it. As a transfer robot, for example, a robot arm having a robot hand that supports a substrate at its tip and a drive unit that drives the robot arm, and a detection unit such as an optical sensor provided on the transfer path of the transfer robot are provided. (For example, see the following Patent Document 1).

  As another example of the transfer robot, a robot hand having a suction surface capable of sucking and holding a circular plate-shaped workpiece is provided, and a plurality of suction holes communicating with a suction source are formed on the suction surface. Some have a built-in recognition sensor (for example, an electrostatic sensor) for determining the presence or absence.

  When transporting a plate-like workpiece by the transfer robot configured as described above and processing the plate-like workpiece, shut off the suction source connected to the suction surface of the robot hand and hold the plate-like workpiece by suction. While releasing and supplying air to the said suction surface, air is blown out from the said suction surface, a plate-shaped workpiece is separated, and the plate-shaped workpiece is conveyed to the process destination. When the plate-shaped workpiece carried into the processing destination is processed, the processed plate-shaped workpiece is conveyed to the cleaning process. Then, a cleaning process and a drying process are performed on the plate workpiece.

No. 2009-084630

  However, moisture may adhere to the plate-like workpiece even though the above-described drying treatment is performed on the plate-like workpiece. For this reason, after a plate-like workpiece is placed on the suction surface of the robot hand of the transfer robot, the plate-like workpiece may not be separated from the suction surface due to the surface tension of moisture intervening between the suction surface and the plate-like workpiece. .

  Even if a recognition sensor for recognizing the presence or absence of a plate-like workpiece is incorporated as in the robot hand described above, for example, when the plate-like workpiece is placed off the suction surface of the robot hand, the recognition sensor is It may not be possible to recognize whether there is a plate-like workpiece on the suction surface.

  Therefore, in actuality, even though the plate-like workpiece is held on the suction surface of the robot hand, the recognition sensor erroneously recognizes that there is no plate-like workpiece on the suction surface of the robot hand. There is a problem that the plate-shaped workpiece is damaged when trying to take out a new plate-shaped workpiece from the cassette in which the workpiece is accommodated.

  The present invention has been made in view of the above circumstances, and there is a problem to be solved by enabling the determination of the presence or absence of a plate-like workpiece over the entire suction surface of the robot hand.

The present invention relates to a cassette for storing a plate-shaped workpiece, a temporary table on which a plate-shaped workpiece before processing is temporarily placed, a cleaning table for cleaning the plate-shaped workpiece after processing, and a suction for sucking and holding the plate-shaped workpiece. A transfer robot including a robot hand having a surface, and a transfer unit provided in a processing apparatus including: an image pickup unit that picks up an image of the robot hand; Storage unit for storing captured image of robot hand when not held, captured image stored in storage unit, and imaging of suction surface acquired by imaging unit when transfer robot starts or ends transfer It includes a determination unit for determining a difference by comparing the image, and prior to processing the plate workpiece, the imaging image by imaging the robot hand in a state where not placed anything on the suction surface After carrying out the first imaging step to be stored in the storage unit, the processing step for processing the plate workpiece, the first imaging step and the processing step, and transporting the processed plate workpiece to the cassette Before taking out the next workpiece to be processed from the cassette, the second imaging step for imaging the robot hand, and the image picked up in the second imaging step by the determination unit and stored in advance A plate-like workpiece presence / absence determining step of comparing the picked-up image stored in the unit and determining whether or not the plate-like workpiece is held on the suction surface of the robot hand.

  The present invention provides an image pickup means for picking up an image of a robot hand in a transport unit, and a storage section for storing an image picked up by the image pickup means when picked up by the pick-up surface of the robot hand. Since the image pickup image stored in the storage unit and the image pick-up image of the suction surface picked up when the transfer robot starts transfer or transfer ends, a judgment unit that determines a difference is provided. It can be confirmed whether or not it is present in comparison with an image in which nothing is held on the suction surface of the robot hand, and whether or not a plate-like workpiece is held on the suction surface can be reliably recognized. . Therefore, the plate-shaped workpiece is not taken out from the cassette containing the plate-shaped workpiece while the plate-shaped workpiece is held on the suction surface of the robot hand, and the plate-shaped workpiece is damaged. Can be prevented.

It is a perspective view which shows a part of structure of the processing apparatus with which the conveyance robot is mounted. It is a top view which shows the structure of the 1st example of a conveyance robot. It is a top view which shows the state by which the plate-shaped workpiece was attracted | sucked and hold | maintained on the whole surface of the suction surface of the robot hand. It is a top view which shows the state by which the plate-shaped workpiece | work shifted and was hold | maintained at the suction surface of the robot hand. It is a top view which shows the structure of the 2nd example of a conveyance robot.

  The processing apparatus 1 shown in FIG. 1 has shown the structure of a part of processing apparatus by which the 1st example of the conveyance unit which conveys the plate-shaped workpiece | work which is not shown in figure was mounted. First, the processing apparatus 1 will be described.

  The processing apparatus 1 has an apparatus base 10 that extends in the Y-axis direction. A stage 2a and a stage 2b are attached to the front portion of the apparatus base 10 in the Y-axis direction in parallel in the X-axis direction. The stage 2a is provided with a supply cassette 3a for storing the workpiece before processing, and the stage 2b is provided with a recovery cassette 3b for storing the workpiece after processing.

  In the vicinity of the supply cassette 3a and the recovery cassette 3b, a transport unit 4 is provided for carrying out the workpiece from the supply cassette 3a and loading the workpiece into the recovery cassette 3b. The transfer unit 4 includes a transfer robot 5 having a robot hand 50 that sucks and holds a plate-like workpiece.

  As shown in FIG. 2, the transfer robot 5 includes a robot hand 50 that is bifurcated at the tip of an arm 53, and the surface of the robot hand 50 is a suction surface 51 that sucks and holds a plate-like workpiece. Yes. The suction surface 51 has at least four suction holes 52 communicating with a suction source (not shown). When the suction source is activated, the plate-like workpiece can be sucked and held on the suction surface 52 through the suction hole 52 as shown in FIG.

  Further, as shown in FIG. 1, the transport unit 4 has an imaging unit 6 that images the shape of the robot hand 50, and when nothing is placed on the suction surface 51 of the robot hand 50 that is captured by the imaging unit 6. A storage unit 7 in which captured images of the robot hand 50 are stored; an captured image stored in the storage unit 7; an image of the suction surface 51 of the robot hand 50 captured when the transport robot 5 starts or ends transport; And a determination unit 8 that determines the difference between the two images.

  The imaging means 6 shown in FIG. 1 is disposed at a position above the transfer robot 5 in order to take the entire surface of the suction surface 51 of the robot hand 50. Specifically, a frame 9 is disposed on the upper surface of the apparatus base 10 so as to straddle the transfer robot 5, and an imaging unit 6 is disposed on the side of the substantially central portion of the frame 9. The imaging unit 6 includes a CMOS image sensor, for example, and can image the entire suction surface 51 of the robot hand 50.

  The storage unit 7 illustrated in FIG. 1 is connected to the imaging unit 6 and can store a captured image captured by the imaging unit 6. The determination unit 8 is connected to the storage unit 7, and an image of the outer shape of the robot hand 50 stored in the storage unit 7 and an image of the suction surface 51 of the robot hand 50 captured when the transfer robot 5 starts or ends transfer. It is possible to determine whether or not there is a plate-like work on the suction surface 51 by comparing with the image.

  As shown in FIG. 1, in the vicinity of the transport unit 4 configured as described above and within the reach of the robot hand 50 of the transport robot 5, a temporary placement table 11 on which a plate-shaped workpiece before processing is temporarily placed. And the washing | cleaning apparatus 12 which wash | cleans the plate-shaped workpiece after a process is arrange | positioned. The plate-like workpiece placed on the temporary placement table 11 is processed on the rear side in the Y-axis direction in FIG.

  Hereinafter, a series of steps for determining the presence or absence of the plate-like workpiece by the transport unit 4 will be described with reference to FIGS. 1 to 4. A circular plate-like workpiece W shown in FIG. 2 is a workpiece to be processed by the processing apparatus 1 shown in FIG.

(1) First Imaging Step First, the entire surface of the suction surface 51 of the robot hand 50 in a state where nothing is placed on the suction surface 51 shown in FIG. Is picked up by the image pickup means 6 shown in FIG. 1, and this picked-up image is stored in the storage unit 7 in advance. Note that, as shown in FIG. 2, a captured image in a state where nothing is placed on the suction surface 51 of the robot hand 50 is referred to as a captured image F1.

(2) Processing Step Next, in the processing apparatus 1 shown in FIG. 1, the robot hand 50 of the transfer robot 5 enters the supply cassette 3a, holds the plate-like workpiece W, and transfers it to the temporary placement 11 table. Then, after the plate-shaped workpiece is processed, the plate-shaped workpiece W is moved to the cleaning table 12 and subjected to a cleaning process and a drying process. Next, the plate-like workpiece W is accommodated in the collection cassette 3b by the transfer robot 5 shown in FIG. At this time, as shown in FIG. 3, when the plate-like workpiece W is taken out without being displaced onto the suction surface 51 of the robot hand 50, the plate-like work is covered so as to cover the entire suction surface 51 of the robot hand 50. Work W is held. In addition, as shown in FIG. 3, the image acquired by imaging the state in which the plate-like workpiece W is held on the entire surface of the suction surface 51 of the robot hand 50 is referred to as a captured image F2.

  On the other hand, as shown in FIG. 4, when the plate-like workpiece W is taken out in a state of being displaced on the suction surface 51 of the robot hand 50, the plate-like work W is covered so as to cover a part of the suction surface 51 of the robot hand 50. Work W is held. In addition, as shown in FIG. 4, the image acquired by imaging the state in which the plate-like workpiece W is held on a part of the suction surface 51 of the robot hand 50 is defined as a captured image F3.

(3) Second imaging step After carrying out the first imaging step and the processing step, the transfer robot 5 shown in FIG. 1 transfers the processed plate-like workpiece W to the recovery cassette 3b, and then performs the next processing target. The plate-like workpiece W is to be taken out from the supply cassette 3a. Here, if moisture adheres to the plate-like workpiece W that has undergone processing and cleaning, the plate-like workpiece W, the suction surface 51, and the like are held after the plate-like workpiece W is held on the suction surface 51 of the robot hand 50. The plate-like workpiece W may not be separated from the suction surface 51 due to the surface tension of moisture intervening between the two, and the plate-like workpiece W intended to be accommodated in the recovery cassette 3b may remain on the suction surface 51. . Therefore, whether or not there is the plate-like workpiece W on the suction surface 51 in order to prevent the conveyance operation of the transfer robot 5 from continuing while the plate-like workpiece W is held on the suction surface 51 of the robot hand 50. Confirm.

  The transfer robot 5 shown in FIG. 1 moves below the image pickup means 6 at the end of the transfer of the plate work W or before taking out a new plate-like work from the supply cassette 3a, and at least the robot hand 50 is moved by the image pickup means 6. The entire suction surface 51 is imaged. At the time of this image pickup, the same image pickup range as that at the time of image pickup in the first image pickup step is set, and the focal point is set at the same position. The captured image is transmitted to the determination unit 8.

(4) Plate Work Presence / No Judgment Step The judgment unit 8 shown in FIG. 1 compares the captured image captured in the second imaging step with the captured image F1 stored in the storage unit 7 in advance, and the robot hand It is determined whether there is a plate-like workpiece W on the 50 suction surfaces 51.

  Specifically, when the determination unit 8 recognizes that the image captured by the imaging unit 6 matches the captured image F <b> 1 illustrated in FIG. 2, the plate-like workpiece W is placed on the suction surface 51 of the robot hand 50. Judge that there is no. In this case, the transfer robot 5 can take out a new plate-shaped workpiece from the supply cassette 3a and continuously operate.

  On the other hand, if the image picked up by the image pickup means 6 includes the plate-like work W as in the picked-up image F2 or the picked-up image F3, there is a difference between the picked-up image F1 and the robot. It is determined that the plate-like workpiece W is present on the suction surface 51 of the hand 50. In this case, the processing apparatus 1 shown in FIG. 1 moves the transfer robot 5 to the collection cassette 3b and accommodates the plate-like workpiece W in the collection cassette 3b. Through the above steps, the presence or absence of the plate-like workpiece W is determined on the suction surface 51 of the robot hand 50.

  A transfer robot 5A shown in FIG. 5 is a second example of a plate-type workpiece transfer robot. Similarly to the transfer robot 5, the transfer robot 5A includes a robot hand 50 bifurcated at the tip of an arm 53, and the surface of the robot hand 50 is a suction surface 51 for sucking and holding a plate-like workpiece. The suction surface 51 has at least four suction holes 52 communicating with a suction source (not shown). Here, if the color of the plate-like workpiece is similar to the color of the robot hand, the judgment unit 8 shown in FIG. 1 may recognize it incorrectly and the plate-like workpiece may be held by the robot hand. Regardless, it is assumed that it is not held. Therefore, in the transfer robot 5A, the outer edge 54 of the suction surface 51 is bordered with a special color to clarify the contrast, and the plate-like workpiece can be easily detected on the suction surface 51. The transfer robot 5A can operate in the same manner as the transfer robot 5.

  In the transport unit 4 and the transport unit 4A shown in the embodiment, it is possible to determine whether or not there is a plate-like workpiece in comparison with an image including the entire suction surface 51 of the robot hand 50. It is possible to reliably recognize whether there is a plate-like workpiece. Therefore, in a state where the plate-like workpiece is held on the suction surface 51 of the robot hand 50, an attempt is made to take out a new plate-like workpiece from the supply cassette 3a in which the plate-like workpiece is accommodated, and the plate-like workpiece is damaged. This can be prevented.

1: Processing apparatus 2a, 2b: Stage 3a: Supply cassette 3b: Collection cassette 4, 4A: Transfer unit 5, 5A: Transfer robot 50: Robot hand 51: Suction surface 52: Suction hole 53: Arm 54: Outer edge 6: Imaging Means 7: Storage unit 8: Determination unit 9: Frame 10: Device base 11: Temporary placement table 12: Cleaning table

Claims (1)

A robot having a cassette for storing a plate-like workpiece, a temporary placement table on which a plate-like workpiece before processing is temporarily placed, a cleaning table for cleaning the plate-like workpiece after processing, and a suction surface for sucking and holding the plate-like workpiece. In a transfer unit provided in a processing apparatus including a transfer robot including a hand,
The transport unit includes an imaging means for imaging the robot hand;
A storage unit that stores an image captured by the robot hand when captured by the imaging unit and nothing is held on the suction surface;
A determination unit that compares the captured image stored in the storage unit and the captured image of the suction surface acquired by the imaging unit when the transfer robot starts or ends transfer, and determines a difference;
A first imaging step of imaging the robot hand in a state where nothing is placed on the suction surface and storing the captured image in the storage unit before processing the plate-like workpiece;
A machining process for machining a plate-like workpiece;
After carrying out the first imaging step and the processing step, the robot hand is imaged after the processed plate-shaped workpiece is transferred to the cassette and before the next workpiece to be processed is taken out from the cassette. A second imaging step,
Whether or not the plate-like work is held on the suction surface of the robot hand by comparing the picked-up image picked up in the second pick-up step with the picked-up image stored in the storage unit in advance by the determining unit . A plate-like workpiece presence / absence judging step for judging
A method for determining the presence or absence of a plate-shaped workpiece.

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