JP2012104562A - Cutting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cutting device capable of retracting a cutting blade from a workpiece by catching a sign of the generation of chipping on a cutting edge of the cutting blade.SOLUTION: A cutting device comprises a chuck table mechanism 3 equipped with a chuck table 35, and supporting members 32 and 34 for supporting the chuck table 35; cutting means equipped with a cutting blade, a cutting feeding means for relatively feeding the chuck table 35 and the cutting means; cut feeding means for feeding the cutting means in a cut feeding direction vertical to a holding surface of the chuck table 35; and controlling means. The cutting device is equipped with a force sensor 36 disposed between the chuck table 35 and the supporting members 32 and 34, and outputting a detection signal corresponding to force applied on the chuck table 35. The controlling means outputs an alarm signal to display means and actuates the cut feeding means to move the cutting means in a retracting direction which separates from the holding surface of the chuck table 35, when the detection signal from the force sensor 36 is not less than a set value.

Description

  The present invention relates to a cutting apparatus for cutting a workpiece such as a semiconductor wafer.

  For example, in a semiconductor device manufacturing process, devices such as IC and LSI are formed in a number of regions partitioned by dividing lines called streets formed in a lattice shape on the surface of a semiconductor wafer having a substantially disk shape, Individual devices are manufactured by dividing each region in which the devices are formed along a street. As a dividing device for dividing a semiconductor wafer, a cutting device as a dicing device is generally used. The cutting apparatus includes a chuck table mechanism having a chuck table having a holding surface for holding a workpiece, and a cutting means having a cutting blade held by the chuck table of the chuck table mechanism to cut the workpiece. A cutting feed means for cutting and feeding the chuck table and the cutting means relative to each other in a cutting feed direction; and a cutting feed means for cutting and feeding the cutting means in a cutting feed direction perpendicular to the holding surface of the chuck table. Yes.

  In the above-described cutting apparatus, the cutting edge may be chipped when the wafer is being cut by the cutting blade. When chips are generated on the cutting edge of the cutting blade, there is a problem that many chips are generated along the streets of the cut wafer and the quality of the device is remarkably deteriorated. In order to solve such a problem, a technique for stopping the operation of the cutting apparatus by capturing a sound wave generated when the cutting blade is broken has been proposed. (For example, refer to Patent Document 1.)

JP-A-60-259360

Thus, the above-described cutting apparatus has a problem that there is a lot of noise because cutting water is supplied to the cutting portion by the cutting blade, and the operation of the cutting apparatus may be stopped due to a malfunction, resulting in poor productivity.
In wafer cutting with a cutting blade, the damage to the device is large at the moment when the cutting edge of the cutting blade is chipped, so the cutting blade is removed from the work piece immediately before the chipping of the cutting blade occurs. It is desirable to evacuate.

  The present invention has been made in view of the above-mentioned facts, and a main technical problem thereof is a cutting apparatus capable of accurately capturing a sign of chipping of the cutting blade and retracting the cutting blade from the workpiece. Is to provide.

In order to solve the above main technical problem, according to the present invention, a chuck table having a holding surface for holding a workpiece, a chuck table mechanism including a support member for supporting the chuck table, and a chuck of the chuck table mechanism A cutting means having a cutting blade that is held by a table and has a cutting blade for cutting a workpiece, a cutting feed means for cutting and feeding the chuck table and the cutting means relatively in a cutting feed direction, and the cutting means as a chuck table In a cutting apparatus comprising a cutting feed means for cutting and feeding in a cutting feed direction perpendicular to the holding surface, and a control means,
A force sensor disposed between the chuck table and the support member and outputting a detection signal corresponding to the force acting on the chuck table;
When the detection signal from the force sensor is equal to or higher than a set value, the control means outputs an alarm signal to the display means and operates the cutting feed means to separate the cutting means from the holding surface of the chuck table. Move it in the retracting direction,
A cutting device is provided.

  The cutting device according to the present invention outputs a warning signal to the display means and performs cutting when the voltage signal from the force sensor disposed between the support member of the chuck table support mechanism and the chuck table is equal to or higher than a set value. By operating the feed means and moving the cutting means in the retracting direction away from the holding surface of the chuck table, it is possible to accurately detect cutting blade abnormalities without being affected by disturbances such as cutting water. it can. Then, the cutting blade can be immediately retracted from the workpiece.

The perspective view of the cutting device equipped with the chuck table mechanism comprised according to this invention. The disassembled perspective view of the chuck table mechanism with which the cutting apparatus shown in FIG. 1 is equipped. Sectional drawing of the chuck table mechanism with which the cutting apparatus shown in FIG. 1 is equipped. AA line sectional view in FIG. The principal part sectional drawing of the cutting means with which the cutting apparatus shown in FIG. 1 is equipped. The block diagram of the configuration of the control means equipped in the cutting apparatus shown in FIG. The perspective view which shows the state which stuck the semiconductor wafer as a to-be-processed object on the surface of the dicing tape with which the cyclic | annular flame | frame was mounted | worn. Explanatory drawing of the cutting process implemented by the cutting device shown in FIG. Explanatory drawing of the voltage signal which the force sensor with which the cutting apparatus shown in FIG. 1 is equipped outputs.

  Hereinafter, a preferred embodiment of a cutting device configured according to the present invention will be described in more detail with reference to the accompanying drawings.

FIG. 1 shows a perspective view of a cutting device constructed in accordance with the present invention.
The cutting apparatus shown in FIG. 1 includes a stationary base 2, a chuck table mechanism 3 that is disposed on the stationary base 2 and holds a workpiece, and an arrow that indicates the direction in which the chuck table mechanism 3 is cut. A chuck table moving mechanism 4 that is movably supported in the cutting feed direction indicated by X, and a direction indicated by an arrow Y that is an indexing feed direction on the stationary base 2 (a direction that is orthogonal to the direction indicated by the arrow X that is the cutting feed direction). A spindle support mechanism 5 movably disposed on the spindle support 6 and a spindle unit 6 as a cutting means movably disposed on the spindle support mechanism 5 in a direction indicated by an arrow Z that is a cutting feed direction are disposed. Yes.

The chuck table mechanism 3 will be described with reference to FIGS.
The chuck table mechanism 3 in the illustrated embodiment includes a chuck table support base 30, a chuck table support mechanism 31 disposed on the upper surface of the chuck table support base 30, and a chuck supported by the chuck table support mechanism 31. A table 35 is provided. The chuck table support base 30 is formed in a rectangular shape, and two guided grooves 301 and 301 are formed on the lower surface thereof.

  The chuck table support mechanism 31 includes a fixed support member 32 and a rotation support member 34 that is rotatably fitted on the outer periphery of the fixed support member 32 via a bearing means 33. The fixed support member 32 is formed in a cylindrical shape as shown in FIG. 3, and the lower end thereof is fixed to the upper surface of the chuck table support base 30. The rotation support member 34 is also formed in a cylindrical shape, and is rotatably supported by the fixed support member 32 via bearing means 33.

  An annular chuck table support portion 341 is provided at the upper end of the rotation support member 34 of the chuck table support mechanism 31 configured as described above, and the annular chuck table support portion 341 is formed from the upper end of the fixed support member 32. It is configured to protrude upward. A chuck table 35 is mounted on the upper surface of the annular chuck table support 341 via a force sensor 36. As shown in FIG. 4, four force sensors 36 are arranged on the upper surface of the annular chuck table support portion 341, and are inserted through holes 361 formed at the center of each force sensor 36a, 36b, 36c, 36d. The fastening screw 37 is disposed between the annular chuck table support portion 341 and the chuck table 35. The force sensors 36a, 36b, 36c, and 36d disposed between the rotation support member 34 and the chuck table 35 in this way are indicated on the chuck table 35 by a cutting feed direction indicated by an arrow X in FIG. A voltage signal corresponding to the force acting in the index feed direction and the cutting feed direction indicated by the arrow Z is output to the control means described later. As such a force sensor, a 9167A / 9168A type force sensor manufactured and sold by Nippon Kistler Co., Ltd. or a thin film strain gauge type 6-axis force sensor manufactured and sold by Nitta Corporation can be used.

  The chuck table 35 includes a columnar main body 351 and an adsorption chuck 352 formed on a porous member made of porous ceramics or the like provided on the upper surface of the main body 351 and having numerous suction holes. The main body 351 is formed of a metal material such as stainless steel, and a circular fitting recess 351a is provided on the upper surface thereof. The fitting recess 351a is provided with an annular mounting shelf 351b on which the suction chuck 352 is mounted on the outer peripheral portion of the bottom surface. The suction chuck 352 fitted in the fitting recess 351a of the main body 351 is placed on the annular placement shelf 351b. The main body 351 is provided with a suction passage 351c that opens to the fitting recess 351a. The suction passage 351c communicates with suction means (not shown). Therefore, when a suction means (not shown) is operated, a negative pressure is applied to the fitting recess 351a through the suction passage 351c, and as a result, a negative pressure is applied to the holding surface, which is the upper surface of the suction chuck 352 having numerous suction holes. It is done. Further, an annular groove 351d is formed in the intermediate portion of the main body 351 as shown in FIG. The bases of four clamps 353 are disposed in the annular groove 351d, and the bases of the clamps 353 are attached to the main body 351 by appropriate fixing means.

  The chuck table mechanism 3 in the illustrated embodiment includes rotation driving means 38 for rotating the rotation support member 34 of the chuck table support mechanism 31 that supports the chuck table 35. The rotation driving means 38 in the illustrated embodiment includes a pulse motor 381 disposed on the chuck table support base 30, a drive pulley 382 mounted on a drive shaft 381 a of the pulse motor 381, and the rotation support member 34. It consists of a driven pulley 383 provided on the outer periphery of the lower end portion, a driving pulley 382 and an endless belt 384 wound around the driven pulley 383. The rotation driving means 38 configured in this manner rotates the rotation support member 34 that supports the chuck table 35 via the drive pulley 382, the endless belt 384, and the driven pulley 383 by driving the pulse motor 381. As described above, since the rotation motor 381 is provided independently of the rotation support member 34 in the rotation driving means 38, the rotation support member 34 does not thermally expand even if the pulse motor 381 generates heat by operation. The height position of the chuck table 35 can always be maintained at a predetermined position. In the illustrated embodiment, the rotation driving means 38 is an example in which a belt mechanism is used as a power transmission mechanism that transmits the driving force of the pulse motor 381 to the rotation support member 34. However, a gear mechanism may be used as the power transmission mechanism. Good.

  Further, the chuck table mechanism 3 in the illustrated embodiment includes a cover table 39 that covers the lower periphery of the chuck table 35. The cover table 39 is supported by four support columns 390 erected at the four corners of the chuck table support base 30. An opening 391 is formed at the center of the cover table 39, and a flange portion 392 that protrudes upward is provided at the periphery of the opening 391. The flange portion 392 is positioned inside a skirt portion 351e formed at the lower end portion of the main body 351 constituting the chuck table.

  Returning to FIG. 1 and continuing the description, the chuck table moving mechanism 4 that supports the chuck table mechanism 3 so as to be movable in the cutting feed direction indicated by the arrow X that is the cutting feed direction is indicated on the stationary base 2 by the arrow X. It comprises a pair of guide rails 41 and 41 arranged in parallel along the direction shown, and a cutting feed means 42 for moving the chuck table mechanism 3 along the pair of guide rails 41 and 41. Two guided grooves 301, 301 provided on the lower surface of the chuck table support base 30 constituting the chuck table mechanism 3 are slidably fitted to the pair of guide rails 41, 41. The cutting feed means 42 includes a drive source such as a male screw rod 421 disposed in parallel between the two guide rails 41 and 41, and a servo motor 422 for rotationally driving the male screw rod 421. Yes. One end of the male screw rod 421 is rotatably supported by a bearing block 423 fixed to the stationary base 2, and the other end is connected to the output shaft of the servo motor 422. The male screw rod 421 is screwed into a penetrating female screw hole formed in a female screw block (not shown) provided on the lower surface of the center portion of the chuck table support base 30. Therefore, the chuck table mechanism 3 is moved in the cutting feed direction indicated by the arrow X along the pair of guide rails 41 and 41 by driving the male screw rod 421 forward and backward by the servo motor 422.

  The spindle support mechanism 5 includes a pair of guide rails 51, 51 disposed in parallel along the indexing feed direction indicated by an arrow Y on the stationary base 2, and an arrow Y on the pair of guide rails 51, 51. The movable support base 52 is provided so as to be movable in the direction indicated by. The movable support base 52 includes a pair of guide rails 51, a movable support portion 521 that is movably disposed on the guide rails 51, and a mounting portion 522 that is attached to the movable support portion 521. Two guided grooves 521 a and 521 a that are fitted to the pair of guide rails 51 and 51 are formed on the lower surface of the moving support portion 521, and the guided grooves 521 a and 521 a are formed on the pair of guide rails 51 and 51. By fitting, the movable support base 52 is configured to be movable along the pair of guide rails 51, 51. The mounting portion 522 is provided with a pair of guide rails 522a and 522a extending in the direction indicated by the arrow Z on one side surface in parallel.

  The spindle support mechanism 5 in the illustrated embodiment includes index feed means 53 for moving the movable support base 52 along the pair of guide rails 51 and 51 in the index feed direction indicated by the arrow Y. The index feeding means 53 includes a male screw rod 531 disposed in parallel between the pair of guide rails 51, 51, and a drive source such as a pulse motor 532 for rotating the male screw rod 531. One end of the male screw rod 531 is rotatably supported by a bearing block (not shown) fixed to the stationary base 2, and the other end is connected to the output shaft of the pulse motor 532. The male screw rod 531 is screwed into a female screw hole formed in a female screw block (not shown) provided on the lower surface of the central portion of the moving support portion 531 constituting the movable support base 52. Therefore, by driving the male screw rod 531 forward and backward by the pulse motor 532, the movable support base 52 is moved along the pair of guide rails 51, 51 in the indexing feed direction indicated by the arrow Y.

  The spindle unit 6 in the illustrated embodiment includes a unit holder 61, a spindle housing 62 attached to the unit holder 61, and a rotating spindle 63 that is rotatably supported by the spindle housing 62. The unit holder 61 is provided with two guided grooves 61a and 61a slidably fitted to a pair of guide rails 522a and 522a provided in the mounting portion 522, and the guided grooves 61a and 61a. Is fitted to a pair of guide rails 522a and 522a, and is supported so as to be movable in the cutting feed direction indicated by the arrow Z. As shown in FIG. 5, the rotary spindle 63 is disposed so as to protrude from the tip of the spindle housing 62, and a cutting blade 65 is mounted on a blade mount 64 attached to the tip of the rotary spindle 63. The cutting blade 65 includes a disk-shaped base 651 made of aluminum, and a cutting edge 652 attached to the outer peripheral side surface of the base 651. The cutting edge 652 is formed by an electroformed blade in which diamond abrasive grains are bonded to the side surface of the outer periphery of the base 651 by a metal plating such as nickel. The rotary spindle 63 to which the cutting blade 65 configured in this way is attached is driven to rotate by a drive source such as a servo motor 66 as shown in FIG. Continuing the description with reference to FIG. 5, cutting water injection nozzles 67 and 67 for injecting cutting water to the cutting portion by the cutting blade 652 are disposed on both sides of the cutting blade 65. The cutting water jet nozzles 67 and 67 are connected to a cutting water supply unit (not shown).

  1, the spindle unit 6 in the illustrated embodiment shows the unit holder 61 with an arrow Z perpendicular to the holding surface of the chuck table 35 along the pair of guide rails 522a and 522a. A cutting feed means 68 for moving in the cutting feed direction is provided. The cutting feed means 68, like the cutting feed means 42 and the index feed means 53, rotationally drives a male screw rod (not shown) disposed between a pair of guide rails 522a and 522a. And a cutting blade 65 mounted on the unit holder 61, the spindle housing 62, and the rotating spindle 63 by driving the male screw rod (not shown) in the forward and reverse directions by the pulse motor 682. Are moved along the pair of guide rails 522a and 522a in the cutting feed direction indicated by the arrow Z. In the illustrated embodiment, when the pulse motor 682 is driven forward, the spindle unit 6 as a cutting means is moved in a direction close to the holding surface of the chuck table 35, and when the pulse motor 682 is driven reversely, the spindle unit as a cutting means. 6 is moved in a retracting direction away from the holding surface of the chuck table 35.

  Note that an image pickup means 69 for picking up an image of the processing area of the workpiece held on the chuck table 35 is disposed at the tip of the spindle housing 62 constituting the spindle unit 6. The image pickup means 69 is composed of an optical system such as a microscope and an image pickup device (CCD), and sends the picked-up image signal to a control means (not shown).

  The cutting apparatus in the illustrated embodiment includes a control means 10 shown in FIG. The control means 10 is constituted by a computer, and a central processing unit (CPU) 101 that performs arithmetic processing according to a control program, a read-only memory (ROM) 102 that stores a control program and the like, a target thickness and calculation of a workpiece. A readable / writable random access memory (RAM) 103 for storing results and the like, an input interface 104 and an output interface 105 are provided. Detection signals are input to the input interface 104 of the control means 10 from the force sensors 36a, 36b, 36c, and 36d via the amplifiers 360a, 360b, 360c, and 360d, and detection signals are input from the imaging means 69 and the like. The From the output interface 105 of the control means 10, the pulse motor 381 of the rotation drive means 38 constituting the chuck table mechanism 3, the servo motor 422 of the cutting feed means 42, the pulse motor 532 of the index feed means 53, and the spindle unit 6. Control signals are output to the servo motor 66, the pulse motor 682 of the cutting feed means 68, the display means 110, and the like.

The cutting apparatus in the illustrated embodiment is configured as described above, and the operation thereof will be described below.
FIG. 7 shows a state in which a semiconductor wafer 20 as a workpiece is attached to the surface of a dicing tape T attached to an annular frame F. The semiconductor wafer 20 is made of a silicon wafer, and a plurality of areas are defined by a plurality of streets 201 arranged in a lattice pattern on the surface 20a, and devices 202 such as IC and LSI are formed in the partitioned areas. ing.

  In order to cut the semiconductor wafer 20 along the street 201, the chuck table 35 is attached to the surface of the dicing tape T mounted on the annular frame F as shown in FIG. Carry up. When the semiconductor wafer 20 attached to the surface of the dicing tape T attached to the annular support frame F is placed on the chuck table 35, the semiconductor wafer 20 is operated by operating a suction means (not shown). Is sucked and held through the dicing tape T. The annular frame F that supports the semiconductor wafer 20 via the dicing tape T is fixed by a clamp 353.

  Next, the cutting feed means 42 is operated to move the chuck table 35 to the imaging area of the imaging means 69. When the chuck table 35 is positioned in the imaging region of the imaging unit 69, the imaging unit 69 and the control unit 10 execute an alignment operation for detecting a processing region to be cut of the semiconductor wafer 20. That is, the imaging unit 69 and the control unit 10 align the street 201 formed in a predetermined direction of the semiconductor wafer 20 with the cutting edge 652 of the cutting blade 65 that cuts along the street 201 (alignment process). ).

  As described above, when the alignment process for detecting the machining area to be cut of the semiconductor wafer 20 is executed, the chuck table 35 is moved to the cutting work area, and a predetermined street as shown in FIG. One end of 201 is positioned slightly to the right in FIG. 8A from directly below the cutting blade 65. Next, the cutting blade 65 is rotated in the direction indicated by the arrow 65a, and the cutting feed means 68 is operated to cut and feed the cutting blade 65 from the retracted position indicated by the two-dot chain line in the direction indicated by the arrow Z1. The cutting feed amount is set at a position where the cutting edge 652 of the cutting blade 65 reaches the dicing tape T. Then, the cutting feed means 42 is actuated to move the chuck table 35 in the direction indicated by the arrow X1 in FIG. 8A at a predetermined cutting feed speed, and the semiconductor wafer 20 held on the chuck table 35 has a predetermined value. When the other end of the street 201 reaches the left side slightly below the cutting blade 65 as shown in FIG. 8B, the movement of the chuck table 35 is stopped and the cutting blade 65 is moved in the direction indicated by the arrow Z2. Raise to the retracted position indicated by the dotted line. Then, the index is fed to the next street to be cut and the cutting is repeated. As a result, the semiconductor wafer 20 is cut along a predetermined street 201 (cutting process). When the cutting process is performed, cutting water is supplied from the cutting water jet nozzles 67 and 67 to the cutting portion of the cutting blade 65 by the cutting edge 652.

  If the above-described cutting process is performed along all the streets 201 formed in the semiconductor wafer 20 in a predetermined direction, the chuck table 35 is rotated 90 degrees. Then, the above-described cutting process is performed along all the streets 201 formed on the semiconductor wafer 20 in a direction orthogonal to the predetermined direction. As a result, the semiconductor wafer 20 is cut along all the streets 201. In this way, the semiconductor wafer 20 is divided into individual devices 202 by cutting along all the streets 201 of the semiconductor wafer 20. In addition, since the device 202 divided | segmented separately is affixed on the dicing tape T with which the cyclic | annular flame | frame F was mounted | worn, it does not fall apart but the form of a wafer is maintained. The individual devices thus divided are transported to the next process in a state where they are adhered to the dicing tape T attached to the annular frame F.

  When the cutting process described above is performed, chipping may occur in the cutting edge 652 of the cutting blade 65. If cutting is continued in the state where the cutting edge 652 is chipped, many chips are generated along the cutting groove. There is a problem that the quality of the device 202 is significantly reduced. Therefore, in the cutting apparatus in the illustrated embodiment, the chuck table 35 is provided by the four force sensors 36a, 36b, 36c, and 36d disposed between the rotation support member 34 of the chuck table support mechanism 31 and the chuck table 35. The force acting on is detected. These four force sensors 36a, 36b, 36c, and 36d are applied to the force acting on the chuck table 35 in the cutting feed direction indicated by arrow X, the index feed direction indicated by arrow Y, and the cutting feed direction indicated by arrow Z in FIG. The corresponding voltage signal is output to the control means 10 via the amplifiers 360a, 360b, 360c, and 360d. The voltage signal input from the force sensors 36a, 36b, 36c, 36d to the control means 10 via the amplifiers 360a, 360b, 360c, 360d is obtained when the cutting edge 652 of the cutting blade 65 is in a normal state. The cutting resistance is constant and is, for example, 1 mmV as shown in FIG. 9A, but when the cutting edge 652 of the cutting blade 65 is just before the chipping occurs, the cutting edge 652 is slightly curved to increase the cutting resistance. However, it exceeds 3 mmV, for example, as shown in FIG. Therefore, when at least one of the voltage signals input from the force sensors 36a, 36b, 36c, and 36d is equal to or higher than a set value (V1, eg, 3 mmV), the control means 10 is missing in the cutting edge 652 of the cutting blade 65. It is determined that there is a possibility of occurrence, and an alarm signal is output to the display means 110, and the pulse motor 682 of the cutting feed means 68 is driven in reverse to separate the spindle unit 6 as the cutting means from the holding surface of the chuck table 35. It moves in the retreat direction and is positioned at a predetermined standby position.

  As described above, in the cutting apparatus in the illustrated embodiment, the voltage signal from the force sensor 36 disposed between the rotation support member 34 of the chuck table support mechanism 31 and the chuck table 35 is a set value (V1: for example, 3 mmV) or more, since it is determined that the cutting resistance of the cutting blade 652 of the cutting blade 65 is increased and the cutting blade 652 may be chipped, without being affected by disturbance such as cutting water, Abnormality of the cutting edge 652 of the cutting blade 65 can be accurately detected. Then, an alarm signal can be immediately output to the display means 110 and the cutting blade 65 can be retracted from the semiconductor wafer 20 that is a workpiece.

2: stationary base 3: chuck table mechanism 30: chuck table support base 31: chuck table support mechanism 32: fixed support member 33: bearing means 34: rotation support member 35: chuck table 36: force sensor 4: chuck table movement Mechanism 41: Guide rail 42: Cutting feed means 5: Spindle support mechanism 51: Guide rail 52: Movable support base 53: Indexing feed means 6: Spindle unit 61: Unit holder 62: Spindle housing 63: Rotating spindle 65: Cutting blade 66: Servo motor 68: Cutting feed means 69: Imaging means 10: Control means 20: Semiconductor wafer

Claims (1)

Cutting having a chuck table having a holding surface for holding a workpiece, a chuck table mechanism having a support member for supporting the chuck table, and a cutting edge held by the chuck table of the chuck table mechanism for cutting the workpiece. Cutting means provided with a blade, cutting feed means for cutting and feeding the chuck table and cutting means relative to each other in the cutting feed direction, and cutting means for cutting and feeding in a cutting feed direction perpendicular to the holding surface of the chuck table In a cutting apparatus comprising a cutting feed means and a control means,
A force sensor disposed between the chuck table and the support member and outputting a detection signal corresponding to the force acting on the chuck table;
When the detection signal from the force sensor is equal to or higher than a set value, the control means outputs an alarm signal to the display means and operates the cutting feed means to separate the cutting means from the holding surface of the chuck table. Move it in the retracting direction,
The cutting device characterized by the above.

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