JP2024043556A - Cutting method - Google Patents

Abstract

To provide a new technique for detecting abnormalities such as a scratch on a holding surface of a holding table that may be caused accompanying breakage of a cutting blade and existence of foreign matter, so as to avoid additional defect from occurring.SOLUTION: A cutting method, which cuts a work-piece using a cutting device which is equipped with a cutting unit having a blade breakage detector that detects breakage of a cutting blade and a photographing camera that can photograph a holding surface of a holding table, comprises: a cutting step of cutting the work-piece held on the holding table, with the cutting blade; a carrying-out step of carrying out the work-piece from the holding table when the blade breakage detector detects the breakage of the cutting blade; a blade replacing step of replacing the broken cutting blade with another cutting blade, after the carrying-out step; and a holding surface confirming step of confirming whether there is an abnormality in the holding surface, by photographing the holding surface of the holding table with the photographing camera, before or after executing the blade replacing step, after executing the carrying-out step.SELECTED DRAWING: Figure 5

Description

The present invention relates to a cutting method for cutting a workpiece with a cutting device equipped with a cutting blade.

Conventionally, as in a cutting device disclosed in Patent Document 1, for example, a cutting blade wears out as a workpiece is cut, and therefore needs to be replaced periodically. Furthermore, if the cutting blade is damaged while cutting a workpiece, it is also necessary to replace the cutting blade.

Patent Document 1 discloses a blade changing device for automatically changing cutting blades. According to such a blade exchanging device, it is possible to eliminate the problem of damaging the cutting blade due to manual exchanging of the cutting blade by an operator.

On the other hand, a blade breakage detector that can detect breakage of a cutting blade during cutting of a workpiece is known, for example, as disclosed in Patent Document 2.

In a cutting machine equipped with a blade breakage detector and a blade changer, when the blade breakage detector detects a breakage of the cutting blade, the blade changer replaces the broken blade with a new cutting blade and starts cutting the workpiece. resume.

Japanese Patent Application Publication No. 2022-030669 JP 2016-007673 A

When a cutting blade breaks during cutting of a workpiece in a cutting device, pieces of the cutting blade may penetrate the holding table and cause scratches. In addition, pieces of the cutting blade may remain stuck in the holding table.

If the blade changing device automatically replaces the cutting blade and restarts machining the workpiece when there are scratches or foreign objects such as blade fragments stuck on the holding surface of the holding table, the scratches or foreign objects may Machining is started while the workpiece is held on the holding table via the holding table.

If there is a flaw (recess) on the holding surface of the holding table, the workpiece is not locally supported in the recess, and there is a risk that chips or cracks may occur due to cutting in the area that is not locally supported.

In addition, if there is a foreign object such as a blade piece on the holding surface of the holding table, the workpiece will be held with the foreign object sandwiched between the workpiece and the holding table, so when the workpiece is held, There is also a risk that the workpiece may be damaged due to bending or pressure, or that the blade may be damaged due to cutting foreign matter with the cutting blade.

Further, the above-mentioned problems may similarly occur when the cutting blade is replaced manually by an operator, regardless of the blade replacement device. In other words, the operator may replace the cutting blade and start work without noticing that there is a foreign object such as a scratch or a blade fragment stuck on the holding surface of the holding table.

In view of the above problems, the present invention proposes a new technique for detecting abnormalities such as scratches on the holding surface of the holding table or the presence of foreign objects that may occur due to damage to the cutting blade, and for avoiding further problems. It is something.

The problem to be solved by the present invention is as described above, and next, means for solving this problem will be explained.

According to one aspect of the present invention, a cutting method for cutting a workpiece using a cutting device including a holding table having a holding surface for holding a workpiece, a cutting unit including a spindle to which a cutting blade for cutting the workpiece held by the holding table is attached and a blade breakage detector for detecting breakage of the cutting blade attached to the spindle, and an imaging camera capable of imaging the holding surface of the holding table, the cutting method including a cutting step for cutting the workpiece held by the holding table with the cutting blade, a carrying step for removing the workpiece from the holding table when breakage of the cutting blade is detected by the blade breakage detector, a blade replacement step for replacing the broken cutting blade attached to the spindle with another cutting blade after the carrying step is performed, and a holding surface confirmation step for imaging the holding surface of the holding table with the imaging camera and confirming whether or not there is an abnormality in the holding surface after the carrying step is performed and before or after the blade replacement step is performed.

Further, according to one aspect of the present invention, when the blade damage detector detects damage to the cutting blade, a damage position storing step of storing the position of the cutting blade within the holding surface as a damage position; Before performing the cutting step, the holding surface checking step includes an imaging range setting step of setting an imaging range to be imaged by the imaging camera, and in the holding surface checking step, the damage position and the imaging range are set. The image will be taken based on the following.

Further, according to one aspect of the present invention, the method further includes a warning sending step of sending a warning when there is an abnormality in the holding surface in the holding surface checking step.

Further, according to one aspect of the present invention, if there is no abnormality in the holding surface in the holding surface checking step, a loading step of loading the workpiece onto the holding table, and a loading step of loading the workpiece onto the holding table after carrying out the loading step. The method further includes a cutting restart step of cutting the workpiece held on the table with a cutting blade newly installed in the blade exchanging step.

Further, according to one aspect of the present invention, the cutting device includes a blade exchanging device for exchanging a cutting blade attached to the spindle, and in the blade exchanging step, the blade exchanging device exchanges the cutting blade. shall be.

The present invention has the following effects.
That is, according to one aspect of the present invention, after the blade breakage detector detects breakage of the cutting blade, the holding surface checking step detects an abnormality such as the presence of scratches or foreign matter on the holding table, and detects the abnormality. It is possible to avoid problems such as continuing to cut the workpiece while the workpiece is being cut.

FIG. 1 is a diagram showing an embodiment of a cutting device used in carrying out the present invention. FIG. 3 is a diagram showing the cutting device and stock unit with the cover folded down. The figure which shows the structure of a cutting unit. FIG. 3 is a diagram showing the configuration of a blade breakage detector. 1 is a flowchart showing the flow of the cutting method of the present invention. 5A to 5C are diagrams illustrating a cutting step. (A) is a diagram illustrating a state in which a damaged cutting blade is removed. (B) A diagram illustrating a state in which another cutting blade is attached. FIG. 3 is a diagram illustrating a holding surface confirmation step. (A) is a diagram showing an example in which a captured image is acquired by capturing an image of the entire holding surface. (B) is a diagram showing an example of acquiring captured images for a predetermined range.

Hereinafter, embodiments according to one aspect of the present invention will be described with reference to the accompanying drawings. First, a configuration example of a cutting device according to this embodiment will be described. FIG. 1 is a perspective view showing the cutting device 2. FIG. In FIG. 1, the X-axis direction (processing feed direction, first horizontal direction, front-back direction) and the Y-axis direction (indexing feed direction, second horizontal direction, left-right direction) are directions perpendicular to each other. Further, the Z-axis direction (vertical direction, up-down direction, height direction) is a direction perpendicular to the X-axis direction and the Y-axis direction.

The cutting device 2 includes a base 4, and an elevator 6 including a lifting platform 6a is provided at the front corner of the base 4. The elevator 6 includes an elevating mechanism (not shown) and moves the elevating platform 6a up and down along the Z-axis direction.

On the lifting platform 6a of the elevator 6, there is a container 8 in which various tools (parts, consumables, etc.) used in the cutting device 2 are stored via a stock unit 200 (FIG. 2), which will be described later. A cassette 10 that accommodates a plurality of workpieces 11 to be cut by is placed. FIG. 1 shows an example in which a container 8 is placed on the lifting table 6a, and a cassette 10 is placed on the container 8.

The cassette 10 has a pair of side surfaces facing each other. Furthermore, a plurality of guide rails 10a are fixed to each side of the cassette 10, respectively, and arranged at predetermined intervals along the height direction of the cassette 10. A frame unit (workpiece unit) 17 including a workpiece 11 is supported by a pair of guide rails 10a arranged at the same height on both sides.

For example, the workpiece 11 is a disk-shaped wafer made of a semiconductor material such as silicon. The workpiece 11 is divided into a plurality of regions by a plurality of dividing lines (street) arranged in a grid pattern, and devices such as ICs and LSIs are formed on the surface (upper surface) side of each region. be done. By cutting and dividing the workpiece 11 along the dividing line, a plurality of device chips each including a device are manufactured.

Note that there are no restrictions on the material, shape, structure, size, etc. of the workpiece 11. For example, the workpiece 11 may be a wafer made of a semiconductor other than silicon (GaAs, InP, GaN, SiC, etc.), glass, ceramics, resin, metal, or the like. Further, there are no restrictions on the type, quantity, shape, structure, size, arrangement, etc. of devices formed on the workpiece 11, and the workpiece 11 does not need to have any devices formed thereon. Furthermore, the workpiece 11 may be a package substrate such as a CSP (Chip Size Package) substrate or a QFN (Quad Flat Non-leaded package) substrate.

A circular tape (dicing tape) 13 with a diameter larger than that of the workpiece 11 is attached to the back (lower surface) side of the workpiece 11. The tape 13 may be a sheet having a circular film-like substrate and an adhesive layer (glue layer) provided on the substrate. For example, the substrate may be made of a resin such as polyolefin, polyvinyl chloride, or polyethylene terephthalate, and the adhesive layer may be made of an epoxy-, acrylic-, or rubber-based adhesive. The adhesive layer may also be made of an ultraviolet-curing resin that hardens when exposed to ultraviolet light.

The outer periphery of the tape 13 is attached to an annular frame 15 made of metal or the like and having a circular opening in the center. Note that the diameter of the opening of the frame 15 is larger than the diameter of the workpiece 11, and the workpiece 11 is arranged inside the opening of the frame 15.

When the tape 13 is attached to the workpiece 11 and the frame 15, the workpiece 11 is supported by the frame 15 via the tape 13. As a result, a frame unit 17 including the workpiece 11, tape 13, and frame 15 is configured. Then, one or more frame units 17 are housed in the cassette 10.

An opening 4a is provided in a region adjacent to the elevator 6 in the X-axis direction on the upper surface side of the base 4. A cleaning unit 12 for cleaning the workpiece 11 is arranged inside the opening 4a. The cleaning unit 12 includes a spinner table 14 that holds the workpiece 11 and a nozzle (not shown) that is provided above the spinner table 14 and supplies a cleaning liquid such as pure water.

The spinner table 14 is connected to a rotational drive source (not shown) such as a motor that rotates the spinner table 14 around a rotation axis that is generally parallel to the Z-axis direction. While the workpiece 11 is held by the spinner table 14, the workpiece 11 is cleaned by supplying cleaning liquid from the nozzle to the workpiece 11 while rotating the spinner table 14. Note that as the cleaning liquid, a gas-liquid mixed fluid in which a liquid (such as pure water) and air are mixed can also be used.

A pair of guide rails 16 that hold the frame unit 17 are provided above the cleaning unit 12 along the X-axis direction. A moving mechanism (not shown) that moves the pair of guide rails 16 toward and away from each other along the Y-axis direction is connected to the pair of guide rails 16 . By sandwiching the frame unit 17 between the pair of guide rails 16, the position of the frame unit 17 in the Y-axis direction is adjusted.

A rectangular opening 4b is provided on the upper surface side of the base 4 at a position adjacent to the guide rail 16 in the Y-axis direction. The opening 4b is formed so that its longitudinal direction is along the X-axis direction. A flat table cover 18 is arranged inside the opening 4b. Further, on both sides of the table cover 18 in the X-axis direction, bellows-shaped dust-proof and drip-proof covers 20 that are expandable and retractable in the X-axis direction are provided.

A holding table (chuck table) 22 that holds the workpiece 11 and the like is provided on the table cover 18 . The upper surface of the holding table 22 constitutes a flat holding surface that holds the workpiece 11 and the like. Furthermore, a plurality of clamps 24 are provided around the holding table 22 to grip and fix the frame 15 and the like.

For example, the holding table 22 includes a cylindrical frame made of metal such as stainless steel. Further, a circular recess is formed on the upper surface side of the central portion of the frame, and a disc-shaped porous member made of a porous material such as porous ceramics is fitted into this recess. The holding surface of the holding table 22 is connected to a suction source such as an ejector via a porous member, a flow path provided inside the holding table 22, a valve, and the like.

For example, the frame unit 17 is arranged on the holding table 22 so that the front side of the workpiece 11 is exposed upward and the back side of the workpiece 11 (tape 13 side) faces the holding surface of the holding table 22. Ru. Further, the frame 15 is held between a plurality of clamps 24. In this state, when negative pressure from a suction source is applied to the holding surface of the holding table 22, the workpiece 11 is suction-held by the holding table 22 via the tape 13.

Furthermore, a pair of sub-tables 26 are provided on the table cover 18 adjacent to the holding table 22. The pair of sub-tables 26 are arranged on the rear side of the holding table 22 and spaced apart from each other in the Y-axis direction.

The upper surface of the sub-table 26 forms a flat holding surface that holds a plate-shaped member used for setting up, inspecting, evaluating, etc. the cutting process. For example, the holding surface of the sub-table 26 is formed in a rectangular shape and is connected to a suction source such as an ejector via a flow path, valve, etc. provided inside the sub-table 26. A dressing board (not shown) is held on this sub-table 26, and dressing is performed by cutting the cutting blade into the dressing board.

A moving unit and a rotary drive source (not shown) are provided below the table cover 18. The moving unit is composed of a ball screw type moving mechanism or the like that reads a scale to detect the position in the X-axis direction, and moves the holding table 22 and the sub-table 26 along the X-axis direction together with the table cover 18. The rotary drive source is composed of a motor or the like, and rotates the holding table 22 around a rotation axis that is roughly parallel to the Z-axis direction.

The front side of the opening 4b (the area adjacent to the opening 4a) corresponds to a transport area where the workpiece 11 is carried in and carried out. Further, the rear side of the opening 4b corresponds to a processing area where the workpiece 11 is processed. By moving the holding table 22 and the sub-table 26 along the X-axis direction by the moving unit, the holding table 22 and the sub-table 26 can be positioned in the transport area or the processing area.

A cover that constitutes a processing chamber 28 that forms a space in which the workpiece 11 is cut is provided above the processing area. In FIG. 1, the outline of the processing chamber 28 is shown by a chain double-dashed line. The processing chamber 28 is made of metal or the like and has a rectangular parallelepiped shape, and is arranged to cover the processing area. Furthermore, an entrance/exit (opening) 28a through which the blade changing device 100 can pass is provided on the side surface of the processing chamber 28 on the transfer area side.

A pair of cutting units 30 for cutting the workpiece 11 are provided inside the processing chamber 28 so as to face each other in the Y-axis direction. The cutting unit 30 cuts the workpiece 11 by rotating an annular cutting blade to cut into the workpiece 11 . A cutting blade 36 is attached to each cutting unit 30, respectively. Each cutting unit 30 is configured to read the scale, detect the position in the Y-axis direction and the Z-axis direction, and move in the Y-axis direction and the Z-axis direction by a Y-axis movement mechanism and a Z-axis movement mechanism (not shown). be done.

Imaging cameras 70 are disposed on the sides of the pair of cutting units 30, respectively, to image the surface of the workpiece 11 held by the holding table 22 and perform alignment with the cutting units 30. be done. The imaging camera 70 is configured by, for example, a visible light camera equipped with an image sensor that receives visible light and converts it into an electrical signal, an infrared camera equipped with an image sensor that receives infrared rays and converts it into an electrical signal, or the like.

The imaging camera 70 may also be used to image the holding surface of the holding table 22, as will be described in detail later. Furthermore, a dedicated camera for capturing an image of the holding surface of the holding table 22 may be provided separately from the imaging camera 70.

A first transport unit 72 that transports the workpiece 11 is provided above the base 4 . A moving mechanism (not shown) that moves the first transport unit 72 along the X-axis direction and the Y-axis direction is connected to the first transport unit 72 . Further, the first conveyance unit 72 includes an air cylinder, and the air cylinder has a built-in rod that moves up and down along the Z-axis direction.

A holding unit 72a that holds the frame 15 of the frame unit 17, etc. is fixed to the lower end of the rod of the air cylinder. For example, the holding unit 72a includes a plurality of suction pads that suck and hold the upper surface side of the frame 15 of the frame unit 17. Further, a gripping mechanism 72b for gripping an end of the frame 15, etc. of the frame unit 17 is provided at the end of the holding unit 72a on the elevator 6 side.

A second transport unit 74 that transports the workpiece 11 is provided above the holding unit 72a included in the first transport unit 72. A moving mechanism (not shown) that moves the second transport unit 74 along the Y-axis direction is connected to the second transport unit 74 . Further, the second transport unit 74 includes an air cylinder, and the air cylinder has a built-in rod that moves up and down along the Z-axis direction.

A holding unit 74a that holds the frame 15 of the frame unit 17, etc. is fixed to the lower end of the rod of the air cylinder. The configuration of the holding unit 74a is similar to the holding unit 72a of the first transport unit 72.

Further, on the side of the holding table 22, a replacement unit 76 for replacing the cutting blade 36 attached to the cutting unit 30 is provided. The exchange unit 76 has a blade exchange device 100 at the tip of a robot arm 76a, and is capable of automatically exchanging cutting blades. Note that the present invention can also be applied to a cutting device configured without the replacement unit 76.

A plate-shaped cover 78 is provided on the edge of the base 4 on the replacement unit 76 side. One end of the cover 78 is connected to the base 4 via a hinge 80, and the cover 78 is supported so as to be rotatable around the hinge 80, and is configured to be opened and closed automatically by a motor (not shown).

When the workpiece 11 is processed by the cutting unit 30, the cover 78 is in an upright state (open state) along the Z-axis direction, as shown by the two-dot chain line in FIG. On the other hand, when the cutting blade 36 and the like are replaced by the replacement unit 76, the cover 78 is in a lying state (closed state) along the X-axis direction and the Y-axis direction, as shown by the solid line in FIG. This protects the holding surface of the holding table when replacing cutting blades, etc.

As shown in FIG. 2, a stock unit 200 is placed on the cover 78. The stock unit 200 includes a mounting table 202 on which tools such as the cutting blade 36 and the dressing board 21 are placed and accommodated. The mounting table 202 is configured as a plate-like member, and its outer peripheral shape is configured to have the same shape as the frame 15 of the frame unit 17, for example.

The replacement unit 76 removes the used cutting blade 36 from the cutting unit 30 and stores it in the stock unit 200, and also takes out the unused or half-used (secondhand, etc.) cutting blade 36 from the stock unit 200 and stores it in the cutting unit 30. The cutting blade 36 is configured to be automatically replaced by being attached to the cutting blade 36. In addition to the cutting blade 36, other tools such as the dressing board 21 can also be stocked in the stock unit 200.

The stock unit 200 is stored in a container 8 provided in the cutting device 2, and when the cutting blade is replaced, etc., it is pulled out from the container 8 by the first transport unit 72 and transported onto the cover 78 in a closed state. Ru. After the cutting blade has been replaced, etc., the stock unit 200 is stored in the container 8 by the first transport unit 72.

As shown in FIG. 3, in the cutting unit 30, a mount flange 31b is fixed with a fixing bolt 31c to a spindle 31a that is rotationally driven by a motor (not shown), and a cutting blade 36 is attached to a fixing nut 31d with respect to the mount flange 31b. Fixed. The cutting blade 36 in the example of FIG. 3 is configured as a hub blade with a cutting edge 36b formed on a hub base 36a, but it may also be configured as a washer blade with a ring-shaped cutting edge. In the case of a washer blade, both sides of the washer blade are fixed with flanges.

The cutting blade 36 is covered from above with a blade cover 33a. A blade breakage detector 35 is provided on the blade cover 33a. The position of the blade breakage detector 35 is adjustable by adjustment screws 33b and 33c.

A cutting fluid block 33d is fixed to one side of the blade cover 33a. From the cutting fluid block 33d, horizontal portions of a pair of approximately L-shaped cutting fluid nozzles 33e extend so as to face both side surfaces of the cutting blade 36, respectively. From the cutting fluid nozzle 33e, cutting fluid supplied from a cutting fluid supply source (not shown) through a hose 33f is ejected toward the side surface of the cutting blade 36.

A shower block 33g is fixed to the other side of the blade cover 33a. A shower nozzle 33h facing the outer peripheral edge of the cutting blade 36 is formed in the shower block 33g. From the shower nozzle 33h, cutting fluid supplied through the hose 33j from a cutting fluid supply source (not shown) is sprayed toward the outer peripheral edge of the cutting blade 36.

An imaging camera 70 fixed to a moving base (not shown) of a moving mechanism for moving the cutting unit 30 in the YZ direction is provided on the side of the cutting unit 30. The imaging camera 70 moves in the Y-axis direction and the Z-axis direction together with the cutting unit 30, and images the surface of the workpiece held by the holding table, the holding surface of the holding table, and the like.

FIG. 4 shows the configuration of the blade breakage detector 35 provided in the cutting unit 30. The blade breakage detector 35 is arranged to face a substantially gate-shaped sensor bracket 35c in which a groove 35d into which the cutting blade 36b of the cutting blade 36 is inserted is sandwiched between the cutting blade 36b inserted into the groove 35d. The photoelectric sensor includes a light emitting section 35a and a light receiving section 35b.

The sensor bracket 35c is fixed to the blade cover 33a, and its fixed position is adjusted by adjusting screws 33b and 33c, so that the positions of the light emitting part 35a and the light receiving part 35b with respect to the cutting blade 36b can be adjusted.

The light emitting section 35a is connected to a light source (not shown) and emits light. The light receiving section 35b is connected to a light receiving element (not shown), and the light emitted from the light emitting section 35a is detected by the light receiving element. The control unit 82 (FIG. 1) detects a state of damage such as total loss or chipping of the cutting blade 36b based on the amount of light received (transmittance) detected by the light receiving element.

As shown in FIG. 1, each component constituting the cutting device 2 (elevator 6, cleaning unit 12, guide rail 16, holding table 22, clamp 24, sub-table 26, cutting unit 30, imaging camera 70, first transport unit 72, second transport unit 74, exchange unit 76, etc.) are each connected to a control unit (control section) 82. The control unit 82 generates control signals for controlling the operation of each component of the cutting device 2, and controls the operation of the cutting device 2.

For example, the control unit 82 is configured by a computer and includes a processing unit 82a that performs various processes (calculations, etc.) required for the operation of the cutting device 2, and a storage unit 82b that stores various information (data, programs, etc.) used in the processes by the processing unit 82a. The processing unit 82a is configured to include a processor such as a CPU. In addition, the storage unit 82b is configured to include various memories that constitute a main storage device, an auxiliary storage device, etc.

The cutting device 2 described above performs cutting on the workpiece 11 . When processing the workpiece 11, first, the frame unit 17 including the workpiece 11 to be processed is housed in the cassette 10. Then, the cassette 10 is placed on the elevator platform 6a of the elevator 6.

The frame unit 17 accommodated in the cassette 10 is carried out from the cassette 10 by the first transport unit 72. Specifically, the first transport unit 72 moves along the X-axis direction away from the cassette 10 while gripping the end of the frame 15 with the gripping mechanism 72b. Thereby, the frame unit 17 is pulled out from the cassette 10 and placed on the pair of guide rails 16. Then, the frame unit 17 is sandwiched between the pair of guide rails 16, and the frame unit 17 is aligned.

Next, the first transport unit 72 holds the upper surface side of the frame 15 with a holding unit 72a, and transports the frame unit 17 onto the holding table 22 arranged in the transport area. Further, the holding table 22 moves from the transport area to the processing area while holding the back side (tape 13 side) of the workpiece 11 under suction. Thereby, the workpiece 11 is placed inside the processing chamber 28.

Then, after positioning of the workpiece 11 and the cutting unit 30 is performed based on the image acquired by imaging the workpiece 11 with the imaging camera 70, the workpiece 11 is cut by the cutting unit 30. be done. For example, the workpiece 11 is cut along a dividing line and divided into a plurality of device chips.

When the cutting process is completed, the holding table 22 moves to the transport area. Then, the second transport unit 74 holds the upper surface side of the frame 15 with a holding unit 74a, and transports the frame unit 17 from the holding table 22 to the cleaning unit 12. The workpiece 11 is then cleaned by the cleaning unit 12 .

When cleaning of the workpiece 11 is completed, the second transport unit 74 holds the frame 15 with the holding unit 74a and transports the frame unit 17 onto the pair of guide rails 16. Then, the frame unit 17 is sandwiched between the pair of guide rails 16, and the frame unit 17 is aligned. Thereafter, the first transport unit 72 moves toward the cassette 10 side while gripping the frame 15 with the gripping mechanism 72b, and stores the frame unit 17 in the cassette 10.

The storage section 82b of the control unit 82 stores a program that describes a series of operations of the cutting device 2 described above. Then, when the operator instructs the cutting device 2 to process the workpiece 11, the processing section 82a reads out the program from the storage section 82b and executes it, and sends control signals for controlling the operations of each component of the cutting device 2. are generated sequentially.

Next, an example of a cutting method using the cutting device configured as in the above example will be described. FIG. 5 is a flowchart showing each step included in the cutting method.

<Imaging range setting step>
More specifically, this step is a step of setting an imaging range to be imaged by an imaging camera in a holding surface confirmation step to be described later. Setting of the imaging range includes, for example, setting to image the entire area of the holding surface 22a, setting to image a partial area, etc., and which setting is selected in the imaging range setting step.

Specifically, as shown in FIG. 8, in the holding surface confirmation step, which will be described in detail later, the imaging camera 70 is positioned above the holding table 22, and the holding surface 22a is imaged. At the time of this imaging, settings are made such that, for example, the entire area of the holding surface 22a is to be imaged. In this setting, a captured image G1 of the entire area of the holding surface 22a of the holding table 22 as shown in FIG. 9(A) is obtained.

Alternatively, for example, when capturing an image of the holding surface 22a, a setting is made such that a partial area corresponding to a damaged position to be stored in a damaged position storage step to be described later is imaged. In this case, for example, of the holding surface 22a of the holding table 22 as shown in FIG. 9(A), a predetermined range 75 corresponding to the damaged position is imaged, and as shown in FIG. 9(B), A captured image G2 is acquired. The partial area corresponding to the damaged position is, for example, a circular area with a radius of 25 mm centered on the damaged position, or a rectangular area with length and width of 50 mm centered on the damaged position.

<Cutting step>
As shown in FIG. 6, this is a step in which the workpiece 11 held by the holding table 22 is cut with the cutting blade 36.

Specifically, for example, after aligning the position of the cutting blade 36 with the planned division line, the cutting blade 36 is positioned at a predetermined cutting height and rotated at high speed, and cutting fluid is supplied to the cutting blade 36 while the holding table 22 is processed and fed, so that the cutting blade 36 cuts into the workpiece 11 to perform cutting processing. After repeating the processing and index feeds of the holding table 22 to form cutting grooves for the planned division line in the first direction, the holding table 22 is rotated 90 degrees and similarly forms cutting grooves for the division column in the second direction, dividing the workpiece 11 into chips.

<Damaged position memory step>
This is a step of storing the position of the cutting blade within the holding surface as a damaged position when the blade damage detector detects damage to the cutting blade.

Specifically, for example, as shown in FIG. 6, when a cutting blade is chipped and damaged during a cutting step, the control unit 82 (FIG. 1) detects this damage. The control unit 82 (FIG. 1) identifies the position where the cutting blade 36 was located within the holding surface 22a of the holding table 22 from the positional information of the holding table 22 and cutting blade 36 when this damage was detected. (relative position between the cutting blade 36 and the holding surface 22a), and stores this position in the storage unit 82b (FIG. 1) as a damaged position.

The damage position can be defined, for example, on the circular holding surface 22a by an XY coordinate system having the center of the holding surface 22a as the origin. For example, the coordinate position in the X-axis direction is specified by reading a scale with an X-axis moving mechanism that moves the holding table 22 in the X-axis direction, and the coordinate position in the Y-axis direction is specified by moving the cutting unit 30 (FIG. 1) It is identified by reading the scale with a Y-axis moving mechanism that moves in the axial direction.

<Export step>
As shown in FIGS. 3 and 4, this is a step of carrying out the workpiece from the holding table 22 (FIG. 6) when the blade damage detector 35 detects damage to the cutting blade 36.

When the control unit 82 (FIG. 1) detects damage, it stops the movement of the holding table 22 shown in FIG. 6, raises the cutting unit 30 to retreat, and stops the cutting process. Next, the holding table 22 is moved to a position where the workpiece 11 can be carried out, and the workpiece 11 is carried out from the holding table 22 by the first transport unit 72 (FIG. 1). Note that the workpiece 11 may be carried out manually by an operator. By carrying out the workpiece 11 from the holding table 22, a situation is created in which the cutting blade can be replaced.

<Blade replacement step>
After carrying out the unloading step, there is a step of replacing the damaged cutting blade mounted on the spindle with another cutting blade.

Specifically, as shown in FIG. 7, in a configuration including a blade exchange device 100, the damaged cutting blade 36 is removed from the mount flange 31b, and the other cutting blade 36A is attached to the mount flange 31b to perform replacement. It is something to do.

The configuration of the blade exchanging device 100 is not particularly limited, and can be realized by a known configuration. For example, in the configuration shown in FIG. 2, the blade exchange device 100 provided at the tip of the robot arm 76a of the exchange unit 76 places the removed cutting blade 36 on the stock unit 200 and removes it from the stock unit 200. This is done by carrying out another cutting blade 36A. Furthermore, the cutting blade may be replaced manually by an operator, without using the blade changing device 100.

The new cutting blade 36A that is replaced may be unused or may be partially used (second-hand, etc.).

<Retention surface confirmation step>
After the removal step is performed, and before or after the blade replacement step is performed, as shown in FIG. 8, the holding surface 22a of the holding table 22 is imaged by the imaging camera 70 to check for any abnormalities in the holding surface 22a.

As shown in FIG. 8, the imaging camera 70 is positioned above the holding table 22 and images the holding surface 22a. Before imaging, the holding surface 22a may be blown with air using an air blowing unit (not shown).

The imaging range by the imaging camera 70 is set, for example, to cover the entire holding surface 22a in the imaging range setting step described above, and is a captured image of the entire holding surface 22a of the holding table 22 as shown in FIG. 9(A). G1 is obtained. Alternatively, the entire range of the holding surface 22a may be divided into a plurality of regions, each region may be imaged individually, and the captured images of each region may be combined to obtain a captured image of the entire holding surface 22a.

Further, when the imaging range by the imaging camera 70 is set to be a partial area corresponding to the damaged position in the imaging range setting step described above, for example, the predetermined range 75 shown in FIG. is imaged. That is, a partial area centered on the position of the cutting blade within the holding surface 22a when damage to the cutting blade was detected is imaged. In this case, as shown in FIG. 9(B), a captured image G2 in a predetermined range 75 is acquired.

The control unit 82 (FIG. 1) analyzes the captured image to check whether there is any abnormality on the holding surface of the holding table. For example, by capturing an image of the holding surface in a state where there is no abnormality in advance and recording it as a normal image, comparing the normal image with the captured image G1 in FIG. If there is, the shadow K is estimated to be a scratch or a foreign object, and it is determined that there is an abnormality. In addition, for example, when a shadow K exceeding a predetermined width or area is detected by performing image processing such as converting the captured image G1 in FIG. 9A into two gradations using a specific threshold value, the shadow K This is assumed to be a scratch or foreign object, and determined to be abnormal.

Alternatively, the operator may determine that there is an abnormality by visually checking the captured image G1 in FIG. 9(A) on a monitor (not shown). The same applies to the case where only the predetermined range 75 is imaged as shown in FIG. 9(B).

<Warning sending step>
In the holding surface confirmation step, if there is an abnormality in the holding surface, a warning issuing step for issuing a warning is executed. For example, the control unit 82 (FIG. 1) issues an audio warning from a speaker (not shown) or displays a warning on an operation monitor (not shown). Thereby, the operator can be prompted to inspect the holding surface, and necessary measures such as replacing the holding table can be taken.

<Transportation step>
If there is no abnormality in the holding surface in the holding surface confirmation step, the workpiece 11 is carried into the holding table 22 as shown in FIG. 1, and the workpiece 11 is made ready for cutting. The workpiece 11 carried in here may be, for example, a workpiece that was carried out in the middle of processing in the carry-out step due to the detection of damage to the cutting blade, or it may be another new workpiece that has not yet been machined. be.

<Cutting restart step>
As shown in FIG. 1, this is a step in which the workpiece 11 held on the holding table 22 is cut with the newly installed cutting blade 30 in the blade exchange step. Similar to the cutting step described above, the cutting process is performed by the cutting unit 30 as shown in FIG. 6, but the cutting blade 36 is newly installed by replacement.

In addition, when machining a workpiece that was carried out during machining and whose machining was interrupted in the cutting restart step, for example, the machining is performed from the dividing line next to the dividing line (street) where machining was interrupted. do.

According to the above embodiment, after the blade breakage detector detects damage to the cutting blade, the holding surface confirmation step detects an abnormality such as scratches or foreign objects on the holding table, and the abnormality remains unchanged. Problems such as continuous cutting of the workpiece can be avoided.

2 Cutting device 11 Workpiece 22 Holding table 22a Holding surface 30 Cutting unit 33a Blade cover 33d Cutting fluid block 33g Shower block 35 Blade breakage detector 35a Light emitting section 35b Light receiving section 35c Sensor bracket 35d Groove section 36 Cutting blade 36a Hub base 36b Cutting blade 70 Imaging camera 76 Exchange unit 82 Control unit 82a Processing section 82b Storage section 100 Blade exchange device 200 Stock unit G1 Captured image G2 Captured image K Shadow

Claims (5)

A holding table having a holding surface for holding a workpiece, a spindle to which a cutting blade for cutting the workpiece held by the holding table is attached, and a blade for detecting damage to the cutting blade attached to the spindle. A cutting method for cutting a workpiece with a cutting device including a cutting unit having a damage detector and an imaging camera capable of capturing an image of the holding surface of the holding table, the method comprising:
a cutting step of cutting the workpiece held by the holding table with the cutting blade;
a step of carrying out the workpiece from the holding table when the blade breakage detector detects breakage of the cutting blade;
After performing the carrying out step, a blade replacing step of replacing the damaged cutting blade attached to the spindle with another cutting blade;
After carrying out the carrying out step and before or after carrying out the blade replacement step, a holding surface checking step of imaging the holding surface of the holding table with the imaging camera and checking whether there is any abnormality on the holding surface; Cutting method with. a damage position storing step of storing the position of the cutting blade within the holding surface as a damage position when the blade damage detector detects damage to the cutting blade;
an imaging range setting step of setting an imaging range to be imaged by the imaging camera in the holding surface confirmation step before implementing the cutting step;
In the holding surface confirmation step, imaging is performed based on the damaged position and the imaging range.
The cutting method according to claim 1, characterized in that: The cutting method according to claim 1 or 2, further comprising a warning issuing step of issuing a warning if an abnormality is found on the holding surface in the holding surface checking step. If there is no abnormality in the holding surface in the holding surface checking step, a carrying step of carrying the workpiece to the holding table;
Claim 1, further comprising a cutting restart step of cutting the workpiece held on the holding table after carrying out the carrying-in step with a cutting blade newly installed in the blade exchanging step. Or the cutting method according to claim 2. The cutting device includes a blade exchange device for exchanging a cutting blade attached to the spindle,
In the blade changing step, the blade changing device changes the cutting blade.
The cutting method according to claim 1 or claim 2, further comprising: a cutting method.