JP2020061458A - Conveying device for plate type workpiece and conveying method - Google Patents

Abstract

To hold a plate type workpiece in a state of being centered to a table at a conveying without sliding an outer periphery of the workpiece, or convey the plate type workpiece in a state of being centered from the table.SOLUTION: A conveying device 2 comprises: means 20 for sucking and holding a piecework W by spraying an air to a plate type workpiece to generate a negative pressure; and means 21 for moving the means 20 for sucking and holding. The means 20 for sucking and holding, comprises: a base 200; a non-contact holding part 201 that is distributed to the base 200, and sucks and holds the workpiece W in a non-contact by spraying an air to a lower direction from an upper direction of the workpiece W to generate the negative pressure on a workpiece upper surface Wb; a pin 202 that distributes a center of three bases 200 at an equivalent angle to the base 200, and is contacted to a workpiece outer peripheral edge Wd sucked and held by the non-contact holding part 201 to be centered. A lower surface of the pin 202 forms an inclination surface 202b of which an outer peripheral side is lower than a center side of the base 200, and the workpiece outer peripheral edge Wd is contacted to the inclination surface 202b to be centered in the workpiece W when the non-contact holding part 201 sucks and holds the workpiece W.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a carrying device and a carrying method for carrying a plate-shaped work.

  A cutting device that cuts a plate-like work by cutting a cutting blade along a planned dividing line for a plate-like work such as a semiconductor wafer held by a chuck table does not want to damage the upper surface of the plate-like work, so the Bernoulli principle is used. The upper surface of the plate-shaped work is suction-held without contact by the used transport pad and is carried into the chuck table. The transfer pad is provided with a block that is brought into contact with the upper surface of the outer peripheral edge of the plate-like work in order to prevent the plate-like work that is suction-held in a non-contact manner from sliding sideways (see, for example, Patent Document 1).

  The transfer pad of the transfer device disclosed in Patent Document 1 prevents side slippage during transfer of a plate-like work, but does not center the plate-like work. Therefore, there is a transfer pad that is capable of suction-holding without contact using the Bernoulli principle and centering of a plate-like work (for example, see Patent Document 2).

JP, 2014-194991, A Japanese Unexamined Patent Application Publication No. 2015-076469

  The plate-shaped workpiece conveying device described in Patent Document 2 includes a centering mechanism that moves the pin toward the center of the plate-shaped workpiece, and performs centering by bringing the pin into contact with the outer peripheral edge of the plate-shaped workpiece. .

Here, when holding the plate-like work on the chuck table, the plate-like work is slid onto the chuck table while the pins are kept in contact with the outer peripheral edge of the plate-like work. Therefore, there is a problem that the outer peripheral edge of the plate-like work is rubbed by the pin to generate dust, and the dust causes a processing defect.
Therefore, when a plate-like work is sucked and held in a non-contact manner and conveyed, the plate-like work is held in the centered state on the chuck table without rubbing the outer peripheral edge or is carried out in the centered state from the chuck table. There is a problem.

  The present invention for solving the above-mentioned problems is to move a suction holding means for injecting air from above a plate-like work toward a plate-like work to generate a negative pressure and suction-holding the plate-like work, and the suction-holding means. A transporting device for a plate-shaped work, comprising: a moving base, which is connected to the moving means, and a suction device which is arranged on the base and moves downward from above the plate-like work. And a non-contact holding part that generates a negative pressure on the upper surface of the plate-like work by suction and holds the plate-like work in a non-contact manner, and at least three non-contact holders are equidistantly arranged on the base about the center of the base. And a centering pin for centering the plate-like work by bringing the non-contact holding part into contact with the outer peripheral edge of the plate-like work suction-held, and the lower surface of the centering pin is inclined so that the outer peripheral side is lower than the center side of the base. Surface, and the non-contact holding part is a plate When suction-holding the workpiece, a transfer device outer peripheral edge of the plate-shaped workpiece is subjected to centering of the plate-shaped workpiece in contact with the inclined surface.

  The transfer device according to the present invention preferably includes a leaf spring that supports the centering pin so as to be movable upward with respect to the lower surface of the base and biases the centering pin downward.

  Further, the present invention for solving the above-mentioned problems is a carrying method for carrying in a plate-like work on a holding surface of a chuck table by using the carrying device, wherein the non-contact holding part does not contact the plate-like work. A holding step of sucking and holding the centering pin and the inclined surface of the centering pin contacting an outer peripheral edge of the plate-like work to center the plate-like work, and a plate-like shape in which the center of the holding surface of the chuck table and the non-contact holding portion are sucked and held. A carrying-in step in which the center of the work is positioned coaxially, the suction holding means is brought close to the holding surface, the holding surface is communicated with a suction source, and the plate-like work is sucked and held by the suction force of the holding surface. It is a transportation method.

  Further, the present invention for solving the above-mentioned problems is a carrying method for carrying out a plate-shaped work held by a holding surface of a chuck table from the chuck table by using the carrying device, wherein the holding surface is held. Suction holding preparation step of bringing the suction holding means close to the upper surface of the plate-like work being inspected to inject air from the non-contact holding portion to generate a negative pressure, and ejecting air from the holding surface to hold the non-contact holding A step of suction-holding the plate-like work without contacting the portion and centering the plate-like work by bringing the inclined surface of the centering pin into contact with the outer peripheral edge of the plate-like work; and separating the suction-holding means from the holding surface. And a carry-out step of carrying out the plate-shaped work from the holding surface.

  The transport apparatus according to the present invention includes suction holding means for injecting air from above the plate-like work toward the plate-like work to generate a negative pressure and suction-holding the plate-like work, and moving means for moving the suction-holding means. The suction holding means includes a base that is connected to the moving means, and a plate that is arranged on the base and injects air downward from above the plate-like work to generate a negative pressure on the upper surface of the plate-like work. Non-contact holding part that sucks and holds the workpiece in a non-contact manner, and at least three equidistantly arranged on the base centering on the center of the base, and the non-contact holding portion makes contact with the outer peripheral edge of the suction-held plate-like work A centering pin for centering the plate-like work, and the lower surface of the centering pin forms an inclined surface whose outer peripheral side is lower than the center side of the base, and when the non-contact holding part sucks and holds the plate-like work, The outer peripheral edge of the work piece is centered Centering plate workpiece is subjected in contact with the inclined surface of the emissions. Then, the plate-shaped work is held in a state where it is centered on the chuck table without rubbing the outer peripheral edge of the plate-shaped work so that the center of the chuck table and the center of the plate-shaped work coincide with each other, or in the state of being centered from the chuck table. It becomes possible to carry out the plate-shaped work.

  The transfer device according to the present invention includes a plate spring that supports the centering pin so as to be movable upward with respect to the lower surface of the base and urges the centering pin downward. When unloading, the non-contact holding part can appropriately hold the plate-shaped workpiece in a non-contact manner by suction until a predetermined height position where the suction-holding means is held against the plate-shaped workpiece without being obstructed by the frame of the chuck table or the like. It is possible to bring them closer together.

  In the carrying method according to the present invention, in which a plate-like work is carried into the holding surface of the chuck table by using the carrying device, the non-contact holding part sucks and holds the plate-like work in a non-contact manner, and the inclined surface of the centering pin is plate-like. The holding step of contacting the outer peripheral edge of the work and centering the plate-like work, and the center of the holding surface of the chuck table and the center of the plate-like work suction-held by the non-contact holder are coaxially positioned to hold the suction-holding means. And a carrying-in step of bringing the holding surface into communication with a suction source and sucking and holding the plate-shaped work by the suction force of the holding surface, thereby centering on the chuck table without rubbing the outer peripheral edge of the plate-shaped work. In this state, it is possible to hold the plate-shaped work and align the center of the chuck table with the center of the plate-shaped work.

  A carrying method according to the present invention for carrying out a plate-like work held by a holding surface of a chuck table from the chuck table by using the carrying device is such that suction is applied to an upper surface of the plate-like work held by the holding surface of the chuck table. A suction-holding preparation step of bringing the holding means close to each other to inject air from the non-contact holding section to generate a negative pressure, and ejecting air from the holding surface, and the non-contact holding section sucks and holds the plate-shaped workpiece in a non-contact manner. A holding step of bringing the inclined surface of the centering pin into contact with the outer peripheral edge of the plate-like work to center the plate-like work; a carry-out step of separating the suction holding means from the holding surface of the chuck table and carrying out the plate-like work from the holding surface; With the provision of, it becomes possible to carry out the plate-shaped work while being centered from the chuck table.

A state in which the non-contact holding portion sucks and holds the plate-shaped work placed on the mounting table in a non-contact manner and the inclined surface of the centering pin contacts the outer peripheral edge of the plate-shaped work to center the plate-shaped work FIG. FIG. 6 is a cross-sectional view illustrating a state in which the center of the holding surface of the chuck table and the center of the plate-like work suction-held by the non-contact holding unit are coaxially positioned. FIG. 6 is a cross-sectional view illustrating a state in which the suction holding means is brought close to the holding surface of the chuck table and the holding surface of the chuck table is in communication with a suction source. FIG. 6 is a cross-sectional view illustrating a state in which a plate-like work is suction-held by a suction force of a holding surface of a chuck table. It is sectional drawing explaining the carrying-in process in case the thickness of the plate-shaped work which the suction holding means holds is a thicker plate-shaped work. FIG. 6 is a cross-sectional view showing a plate-like work in a state of being suction-held on a chuck table. FIG. 6 is a cross-sectional view illustrating a state where suction holding means is brought close to the upper surface of a plate-shaped work held by a holding surface of a chuck table. It is sectional drawing explaining the state which injects air from a non-contact holding part and produces | generates negative pressure. A cross-section for explaining a state in which air is ejected from the holding surface, the non-contact holding portion sucks and holds the plate-shaped work without contact, and the inclined surface of the centering pin is brought into contact with the outer peripheral edge of the plate-shaped work to center the plate-shaped work. It is a figure. FIG. 6 is a cross-sectional view illustrating a holding process and a carrying-out process when the plate-shaped work held by the suction holding means is a plate-shaped work having a slightly larger diameter.

Below, each step in the case of carrying out the carrying method for carrying in the plate-shaped work W on the holding surface 300a of the chuck table 30 shown in FIG. 2 using the carrying device 2 shown in FIG. 1 will be described.
The plate-shaped work W shown in FIG. 1 is, for example, a circular plate-shaped semiconductor wafer having a base material of silicon, and the lower surface Wa of the plate-shaped work W facing downward in FIG. Devices (not shown) are formed in the formed grid-like regions. The lower surface Wa of the plate-shaped workpiece W is protected by, for example, a protective tape (not shown) attached. The upper surface Wb of the plate-shaped work W facing upward in FIG. 1 is a surface that is suction-held by the transport device 2. In FIG. 1, the plate-shaped work W is in a state of being mounted on the mounting table 10.
The device forming surface of the plate-shaped work W may be a surface that is suction-held by the transport device 2.

(1) Holding Step The conveying device 2 shown in FIG. 1 includes a suction holding unit 20 that sucks and holds the plate-shaped work W by injecting air from above the plate-shaped work W toward the plate-shaped work W to generate a negative pressure. And a moving means 21 for moving the suction holding means 20.

  The suction holding means 20 is fixed to the lower surface side of one end of the arm portion 221 that extends horizontally via the connecting member 220. A moving means 21 is connected to the arm portion 221, and the moving means 21 allows the arm portion 221 to move horizontally or swivel on a horizontal plane (X-axis Y-axis plane) and in a vertical direction (Z-axis direction). ) Can be moved up and down. The moving unit 21 includes, for example, an air cylinder that vertically moves the arm portion 221 in the Z-axis direction by air pressure, a ball screw mechanism that horizontally moves the arm portion 221 by rotating a ball screw by a motor, and the like.

  The suction holding means 20 is provided on the base 200 connected to the moving means 21 via the connecting member 220 and the arm portion 221, and is disposed on the base 200 to inject air downward from above the plate-shaped workpiece W. A non-contact holding portion 201 that generates a negative pressure on the upper surface Wb of the plate-like work W and suction-holds the plate-like work W in a non-contact manner, and at least three non-contact holders are equidistantly arranged on the base 200 around the center of the base 200. The non-contact holding part 201 is provided with a centering pin 202 that contacts the outer peripheral edge Wd of the plate-shaped work W suction-held and centers the plate-shaped work W.

  The base 200 is formed, for example, in a circular plate shape, and the connecting member 220 is connected to the central portion of the upper surface thereof. The shape of the base 200 is not limited to the shape in this embodiment. For example, the base 200 may have an outer shape formed into an annular shape, or may be composed of a plurality of members such as an annular member and a linear member.

  The non-contact holders 201 use Bernoulli's principle, and for example, a plurality of non-contact holders 201 are arranged on the lower surface of the base 200 at equal intervals in the circumferential direction and the radial direction. For example, an air supply passage 201a is formed inside the non-contact holding portion 201 having a disk-shaped outer shape, and the air supply passage 201a is an annular air ejection port formed on the bottom surface of the non-contact holding portion 201. It communicates with 201b. An air supply source 28 including a compressor is connected to the air supply path 201a via a communication path 200c formed inside the base 200. Note that, for example, the air supply path 201a may be formed with an annular orifice or the like that accelerates the air supplied from the air supply source 28 to the non-contact holding unit 201.

  In the present embodiment, the centering pins 202 are supported by the leaf springs 24 fixed to the upper surface outer peripheral region of the base 200 so as to be movable upward with respect to the lower surface of the base 200. The leaf spring 24 is a stainless leaf spring or a rubber leaf spring, which projects radially outward from the outer peripheral edge of the base 200 by a predetermined length, and the upper end surface of the centering pin 202 is screwed to the lower surface of the projecting portion. Adhesive fixed. In the present embodiment, three centering pins 202 are provided on the base 200 at 120 degrees apart in the circumferential direction, but four or more centering pins 202 may be provided.

  The centering pin 202 extends from the leaf spring 24 in the −Z direction at least to a height position below the lower surface of the non-contact holding portion 201 by a predetermined distance. The lower surface of the centering pin 202 forms an inclined surface 202b whose outer peripheral side is lower than the central side of the base 200. The inclination angle of the inclined surface 202b is set to an appropriate angle (for example, 36 degrees to 55 degrees) according to the diameter and thickness of the plate-shaped work W. That is, the lower surface of the non-contact holding part 201 and the upper surface Wb of the plate-like work W are maintained so that the non-contact holding part 201 can maintain the negative pressure for sucking and holding the plate-like work W contacting the inclined surface 202b. The gap between them is set to be a predetermined distance.

  In the holding step, first, the suction holding means 20 is horizontally moved by the moving means 21 so that the center of the base 200 substantially coincides with the center of the plate-like work W, and the suction holding means 20 is moved above the plate-like work W. Positioned. Further, the suction holding means 20 descends in the −Z direction to a height position where the non-contact holding portion 201 and the upper surface Wb of the plate-shaped work W do not contact each other.

  After the suction holding means 20 descends to a predetermined height position in the Z-axis direction, the air supply source 28 supplies high-pressure air to the air supply passage 201a inside the non-contact holding portion 201 via the communication passage 200c of the base 200. Supply. The air supplied to the non-contact holding unit 201 is accelerated in the air supply passage 201a through, for example, an annular orifice (not shown), and is jetted from the air jet outlet 201b onto the upper surface Wb of the plate-shaped work W at high speed.

  The high-pressure air ejected from the air ejection port 201b decelerates while expanding and becomes atmospheric pressure, so that the Bernoulli effect works in the gap between the lower surface of the non-contact holding portion 201 and the upper surface Wb of the plate-like work W, A pressure drop occurs (a negative pressure is generated) in the central portion of the lower surface of the non-contact holding portion 201. That is, due to the Bernoulli effect, a suction force is generated on the upper surface Wb of the plate-shaped work W in a region corresponding to the central portion of the lower surface of the non-contact holding portion 201 as indicated by a thick arrow R1. The suction force indicated by the thick arrow R1 serves as a suction force for sucking and holding the plate-shaped work W in the non-contact holding portion 201 in the non-contact state.

The plurality of non-contact holding portions 201 suction-hold the plate-shaped work W in a non-contact manner, and the inclined surface 202b of the centering pin 202 comes into contact with the outer peripheral edge Wd of the plate-shaped work W lifted by the suction force. The plate-like work W is horizontally moved (centered) while being guided by the centering pin 202 so that the center of 200 and the center of the plate-like work W are exactly aligned.
After that, the moving means 21 raises the suction holding means 20 in the + Z direction, so that the plate-like work W is carried out of the mounting table 10 by the carrying device 2.

(2) Loading Step Next, the moving means 21 moves the suction holding means 20, which holds the plate-shaped workpiece W by suction in a non-contact manner, to above the chuck table 30 shown in FIG. Note that, for example, while the plate-shaped work W is transferred onto the chuck table 30 by the transfer device 2, the plate-shaped work W is subjected to the vibration due to the movement of the suction holding means 20, so that the inclined surface of the centering pin 202 is received. Since the outer peripheral edge Wd of the plate-shaped work W slides on 202b, the plate-shaped work W is centered in the suction holding means 20 with higher accuracy.

The chuck table 30 shown in FIG. 2 has, for example, a circular outer shape, a holding part 300 made of a porous member or the like for sucking and holding the plate-shaped work W, and a frame body 301 surrounding and supporting the holding part 300. Equipped with. The holding unit 300 communicates with a suction source 39 such as a vacuum generator or an ejector via an air passage 390, and a first opening / closing valve 391 is arranged on the air passage 390. Then, by operating the suction source 39 with the first opening / closing valve 391 opened, the suction force generated by the suction source 39 is transmitted to the holding surface 300a, which is the exposed surface of the holding portion 300, and the chuck table 30 moves. The plate-shaped work W can be suction-held on the holding surface 300a. For example, the inner diameter of the frame 301 is smaller than the outer diameter of the plate-shaped work W to be held, and the outer diameter of the frame 301 is formed to be larger than the outer diameter of the plate-shaped work W to be held.
The chuck table 30 is not limited to the example shown in the present embodiment, and may be a holding table in which a suction groove is formed in the holding surface or a pin chuck table in which the holding surface is formed by a plurality of support pins. Good.

  For example, an air source 38 capable of supplying compressed air is connected to the air flow path 390 via a second opening / closing valve 392. The air source 38 is used when the plate-shaped work W sucked and held by the chuck table 30 is released from the holding surface 300a. That is, the air supplied from the air source 38 to the air flow path 390 while the second opening / closing valve 392 is opened reaches the holding portion 300 through the air flow path 390 and goes upward from the holding surface 300a. Gush out. The jetting pressure of the air pushes up the plate-shaped work W from the holding surface 300a, and the residual vacuum suction force between the holding surface 300a and the plate-shaped work W (vacuum suction force remaining after the suction by the suction source 39 is stopped). Therefore, the plate-shaped work W can be reliably separated from the chuck table 30.

  In the carrying-in step, first, as shown in FIG. 2, the suction holding means 20 is moved in the horizontal direction by the moving means 21, and the center of the holding surface 300a of the chuck table 30 and each non-contact holding portion 201 are held by non-contact. The center of the plate-shaped work W is positioned coaxially.

Next, as shown in FIG. 3, by the moving means 21, for example, the lower surface Wa of the plate-shaped work W and the holding surface 300a do not come into contact with each other, and the lowermost end of the centering pin 202 and the frame 301 of the chuck table 30 are arranged. The suction holding means 20 descends in the -Z direction to a position where it comes into contact with the upper surface.
The suction force generated by the suction source 39 is transmitted to the holding surface 300a by operating the suction source 39 after the first opening / closing valve 391 is opened and the holding surface 300a communicates with the suction source 39.

  As shown in FIG. 4, when the suction holding means 20 is further lowered by the moving means 21, the centering pin 202 is pushed upward (in a substantially vertical direction) by the upper surface of the frame body 301 to move, and the centering pin 202 of each centering pin 202 is moved. The horizontal distance between the inclined surfaces 202b is increased. Further, the leaf spring 24 stores a biasing force that pushes the centering pin 202 downward by bending.

Basically, the suction force of the chuck table 30 to draw the plate-shaped work W in the -Z direction is larger than the suction force of the Bernoulli's principle for holding the plate-shaped work W by suction. W falls vertically on the holding surface 300a of the chuck table 30 and is suction-held on the holding surface 300a. Here, since a suction force is applied to each of the plate-like works W in the ± Z directions, it is possible to prevent the plate-like works W from sliding sideways in the horizontal direction when the plate-like works W fall vertically. . Therefore, the center of the plate-like work W suction-held on the chuck table 30 is in a state of being aligned with the center of the holding surface 300a.
Further, since the lower surface of the centering pin 202 forms an inclined surface 202b whose outer peripheral side is lower than the center side of the base 200, when the plate-shaped work W vertically drops, the outer peripheral edge Wd of the plate-shaped work W is reduced. No dust is generated because the inclined surface 202b is not rubbed.

  After the chuck table 30 suction-holds the plate-shaped work W as described above, the air supply source 28 stops the supply of high-pressure air to the non-contact holding unit 201, so that the suction-holding means 20 transfers the plate-shaped work W to the plate-shaped work W. The suction force that was acting disappears. After that, the suction holding means 20 is separated from above the plate-shaped work W by the moving means 21, and the centering pin 202 is returned to the original state by the biasing force accumulated by the plate spring 24.

Note that, for example, a position where the lower surface Wa of the plate-like work W shown in FIG. 3 and the holding surface 300a do not contact each other, and the lowermost end of the centering pin 202 and the upper surface of the frame body 301 of the chuck table 30 contact each other. In the state where the suction holding means 20 is located at the position, the suction force is transmitted from the suction source 39 to the holding surface 300a of the chuck table 30, and the air supply source 28 supplies the high pressure air to the non-contact holding portion 201. Then, the suction holding means 20 stops sucking and holding the plate-shaped workpiece W.
As a result, the vertically dropped plate-shaped workpiece W may be sucked and held by the holding surface 300a of the chuck table 30 while being centered.

  The carrying method for carrying the plate-shaped work W into the holding surface 300a of the chuck table 30 using the carrying device 2 according to the present invention is not limited to the above embodiment. Further, the configurations and the like of the transfer device 2 and the chuck table 30 illustrated in the accompanying drawings are not limited to this, and can be appropriately changed within a range in which the effects of the present invention can be exhibited.

  For example, FIG. 5 is a cross-sectional view illustrating a carry-in step in a carrying method for carrying the plate-shaped workpiece W into the holding surface 300a of the chuck table 30 using the carrying device 2. The plate-like work W2 shown in FIG. 5 is a work having a larger thickness than the plate-like work W shown in FIGS. The plate-shaped work W2 may be, for example, a wafer in which a carrier plate is attached to the wafer.

  Even when the thickness of the plate-like work held by the suction holding means 20 is increased like the plate-like work W2, the Bernoulli is provided in the gap between the lower surface of the non-contact holding unit 201 and the upper surface W2b of the plate-like work W2. In order to exert the effect and generate the suction force for sucking and holding the plate-shaped work W2, it is necessary to keep the gap at the same distance as when the suction-holding means 20 sucks and holds the plate-shaped work W. Therefore, after the center of the holding surface 300a of the chuck table 30 and the center of the plate-like work W2 suction-held by the non-contact holding unit 201 are coaxially positioned, the moving means 21 brings the suction-holding means 20 closer to the holding surface 300a. The stop height position at the time of stopping it, that is, the height position of the lower surface W2a of the plate-like work W2 changes.

Here, since the transport device 2 has previously recognized the information (setting value) about the thickness of the plate-shaped workpiece W2, the height position at which the suction holding means 20 is stopped is determined from the setting value, so that the plate shape It is possible to hold the plate-shaped work W2 in a state of being centered on the chuck table 30 without rubbing the outer peripheral edge W2d of the work W2 so that the center of the chuck table 30 and the center of the plate-shaped work W2 coincide with each other.
In the case of a thick plate-shaped work W2, the suction holding means 20 is brought close to the holding surface 300a to bring the lower surface W2a of the plate-shaped work W2 into contact with the holding surface 300a, and then the holding surface 300a is used to move the plate-shaped work W2. You may hold by suction.

  Hereinafter, each step in the case of carrying out the carrying method for carrying out the plate-shaped work W suction-held by the holding surface 300a of the chuck table 30 shown in FIG. 5 from the chuck table 30 will be described.

(1) Suction and Holding Preparation Step First, as shown in FIG. 7, the moving and holding means 20 causes the suction and holding means 20 to substantially match the center of the base 200 with the center of the plate-shaped workpiece W suction-held by the chuck table 30. The base 200 is positioned above the plate-shaped workpiece W by horizontally moving as described above. Further, the suction holding means 20 descends in the -Z direction to a height position where the non-contact holding portion 201 and the upper surface Wb of the plate-shaped work W do not come into contact with each other. In this state, the outer peripheral edge Wd of the plate-like work W is surrounded by the inclined surface 202b of the centering pin 202.
Further, the inclined surface 202b is formed so that the outer peripheral edge Wd of the plate-shaped work W and the inclined surface 202b of the centering pin 202 do not contact with each other in the state where the lowermost end of the centering pin 202 is in contact with the upper surface of the frame body 301. Good.

As shown in FIG. 8, when the suction holding means 20 is further lowered by the moving means 21, the centering pin 202 is pushed upward (in a substantially vertical direction) by the upper surface of the frame 301 to move, and the centering pin 202 of each centering pin 202 is moved. The horizontal distance between the inclined surfaces 202b is increased. The leaf spring 24 stores a biasing force that pushes the centering pin 202 downward by bending. Further, the air supply source 28 supplies air to each of the non-contact holding portions 201, so that suction is performed upward on the upper surface Wb of the plate-shaped workpiece W to a region corresponding to the central portion of the lower surface of the non-contact holding portion 201. Force is generated (negative pressure is generated).
As in the present embodiment, the centering pin 202 of the suction holding means 20 can be moved upward with respect to the lower surface of the base 200 by the plate spring 24, so that the non-contact holding part 201 can appropriately move the plate-shaped work W. The suction holding means 20 can be brought close to the plate-like work W without being hindered by the frame 301 of the chuck table 30 up to a predetermined height position where suction holding can be performed in a non-contact manner.

(2) Holding Step As shown in FIG. 8, the first opening / closing valve 391 is closed and the suction force of the holding surface 300a is lost. Further, after the second opening / closing valve 392 is opened, the air source 38 supplies air to the chuck table 30, and the supplied air is jetted upward from the holding surface 300a. Then, the vacuum suction force remaining between the holding surface 300a and the plate-shaped work W is eliminated by the ejected air, and the suction holding means 20 can reliably separate the plate-shaped work W from the chuck table 30 and hold it by suction. It will be in a state.

  As a result, as shown in FIG. 9, the plurality of non-contact holding portions 201 suck and hold the plate-shaped works W in a non-contact manner to bring the plate-shaped works W close to the plurality of non-contact holding parts 201 and to perform the centering pin. When the inclined surface 202b of the plate 202 is brought into contact with the outer peripheral edge Wd of the lifted plate-like work W, the plate-like work W is aligned with the centering pin so that the center of the base 200 and the center of the plate-like work W are accurately aligned. It is horizontally moved (centered) while being guided by 202.

(3) Unloading Step The moving means 21 raises the suction holding means 20 in the + Z direction and separates it from the holding surface 300a of the chuck table 30, so that the transport device 2 carries out the plate-shaped workpiece W from the chuck table 30. It Further, the centering pin 202 tries to return to the original state by the biasing force accumulated by the leaf spring 24, and the distance between the inclined surfaces 202b of each centering pin 202 in the horizontal direction is the inclined surface 202b of the plate-shaped work W. The plate-like work W is kept centered in the suction holding means 20 because it tries to contract to the original distance while maintaining contact with the outer peripheral edge Wd.

  Note that, for example, the plate-shaped work W is subjected to vibration due to the movement of the suction holding means 20 until the plate-shaped work W is transferred to the next loading place by the transfer device 2, so that the inclined surface of the centering pin 202 is received. Since the outer peripheral edge Wd of the plate-shaped work W slides on 202b, the plate-shaped work W is centered in the suction holding means 20 with higher accuracy.

  The transport method for unloading the plate-shaped work W held by the holding surface 300a of the chuck table 30 from the chuck table 30 using the transport device 2 according to the present invention is not limited to the above embodiment. Further, the configurations and the like of the transfer device 2 and the chuck table 30 illustrated in the accompanying drawings are not limited to this, and can be appropriately changed within a range in which the effects of the present invention can be exhibited.

  For example, FIG. 10 is a cross-sectional view illustrating a holding process and a carrying-out process in a carrying method for carrying out, from the chuck table 30, the plate-shaped workpiece W1 held by the holding surface 300a of the chuck table 30 by suction. The plate-like work W1 shown in FIG. 10 is a work having a slightly larger diameter than the plate-like work W shown in FIGS. 6 to 9. Thus, even when the diameter of the plate-like work held by the suction holding means 20 is slightly increased like the plate-like work W1, air is ejected from the holding surface 300a of the chuck table 30 to hold it in a non-contact manner. The portion 201 can suction-hold the plate-shaped work W1 without contacting it, and the inclined surface 202b of the centering pin 202 can be brought into contact with the outer peripheral edge W1d of the plate-shaped work W1 to center the plate-shaped work W1.

  That is, the Bernoulli effect works in the gap between the lower surface of the non-contact holding part 201 and the upper surface W1b of the plate-shaped work W1, and in order to generate a suction force for holding the plate-shaped work W1 by suction, the gap is set to a predetermined value. You need to keep a distance. Here, the transfer device 2 includes a leaf spring 24 that supports the centering pin 202 so as to be movable upward with respect to the lower surface of the base 200 and biases the centering pin 202 downward. Therefore, in the holding step, even after the inclined surface 202b of the centering pin 202 contacts the outer peripheral edge W1d of the plate-shaped workpiece W1, the horizontal distance between the inclined surfaces 202b of the centering pins 202 is the inclined surface 202b. By expanding while maintaining contact with the outer peripheral edge W1d of the work W1, the upper surface W1b of the plate-shaped work W1 can be brought close to the non-contact holding portion 201 so that the gap has a predetermined distance. At the same time, while the outer peripheral edge W1d of the plate-shaped work W1 is in contact with the inclined surface 202b of the centering pin 202, the plate-shaped work W1 can be horizontally moved so as to be centered while being pushed downward by the centering pin 202.

  Further, as shown in FIG. 10, even when the suction holding means 20 is separated from the holding surface 300a of the chuck table 30 and the plate-shaped work W1 is carried out from the holding surface 300a, the centering pin 202 is moved downward by the plate spring 24. Since the distance in the horizontal direction between the inclined surfaces 202b of the centering pins 202 is biased to the original distance, the inclined surface 202b remains in contact with the outer peripheral edge W1d of the plate-shaped work W1. As a result, the plate-like work W1 is kept centered in the suction holding means 20.

W: Plate-shaped work Wb: Upper surface of plate-shaped work 2: Transfer device 20: Suction holding means 200: Base 200c: Communication passage 201: Non-contact holding portion 201a: Air supply passage 201b: Air jet 202: Centering pin 202b : Inclined surface of centering pin 21: moving means 220: connecting member 221: arm part 24: leaf spring 28: air supply source
30: Chuck table 300: Holding part 300a: Holding surface 301: Frame 39: Suction source 390: Air flow path 391: First opening / closing valve 38: Air source 392: Second opening / closing valve

Claims (4)

Conveyance of a plate-like work including suction holding means for injecting air from above the plate-like work toward the plate-like work to generate a negative pressure and sucking and holding the plate-like work, and moving means for moving the suction-holding means A device,
The suction holding means is provided with a base connected to the moving means, and is provided on the base to inject air downward from above the plate-like work to generate a negative pressure on the upper surface of the plate-like work. -Contact holding part for sucking and holding non-contact workpieces, and at least three peripheral edges of plate-like workpieces arranged at equal angles on the base around the center of the base and suction-held by the non-contact holding portions And a centering pin for centering the plate-shaped workpiece
The lower surface of the centering pin forms an inclined surface whose outer peripheral side is lower than the center side of the base, and when the non-contact holding part sucks and holds the plate-shaped work, the outer peripheral edge of the plate-shaped work contacts the inclined surface. A transport device for centering plate-shaped workpieces.   The transport apparatus according to claim 1, further comprising a leaf spring that supports the centering pin so as to be movable upward with respect to a lower surface of the base and biases the centering pin downward. A transport method for loading a plate-shaped workpiece onto a holding surface of a chuck table using the transport device according to claim 1.
A holding step in which the non-contact holding section sucks and holds a plate-shaped work in a non-contact manner, and the inclined surface of the centering pin contacts the outer peripheral edge of the plate-shaped work to center the plate-shaped work.
The center of the holding surface of the chuck table and the center of the plate-like work suction-held by the non-contact holding portion are coaxially positioned, the suction-holding means is brought close to the holding surface, and the holding surface is communicated with a suction source. A carrying-in step of sucking and holding the plate-like work by the suction force of the holding surface. A transport method for unloading a plate-shaped work held by a holding surface of a chuck table from the chuck table using the transport device according to claim 1.
A suction-holding preparation step of causing the suction-holding means to approach the upper surface of the plate-like work held by the holding surface and injecting air from the non-contact holding section to generate a negative pressure;
A holding step of ejecting air from the holding surface so that the non-contact holding portion sucks and holds the plate-shaped work in a non-contact manner, and the inclined surface of the centering pin is brought into contact with the outer peripheral edge of the plate-shaped work to center the plate-shaped work. When,
And a carrying-out step of moving the suction holding means away from the holding surface and carrying out the plate-shaped work from the holding surface.

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