JP7098239B2 - Nozzle height inspection method and cutting equipment - Google Patents

Description

The present invention relates to a cutting device that cuts a workpiece with a cutting blade and a method for inspecting the height of a nozzle that supplies cutting water to the cutting blade in the cutting device.

A device chip on which a semiconductor device is mounted is formed by dividing a semiconductor wafer, a package substrate, or the like. The surface of a semiconductor wafer or the like is partitioned by a plurality of intersecting scheduled division lines, semiconductor devices are formed in each of the partitioned regions, and then the semiconductor wafer or the like is divided along the scheduled division lines to form individual device chips. can.

For dividing a semiconductor wafer or the like, for example, a cutting device provided with a cutting unit equipped with an annular cutting blade is used. In the cutting equipment, the cutting blade is rotated in a plane perpendicular to the surface of the workpiece such as a semiconductor wafer, the cutting blade is lowered to a predetermined height position in the cutting feed direction, and the workpiece is to be divided. The work piece is cut with a cutting blade by processing and feeding in the direction along.

When a work piece is cut with a cutting blade, cutting chips derived from the work piece are generated and scattered around the work piece. In addition, processing heat is generated. Therefore, the cutting device is provided with a nozzle for supplying cutting water in the vicinity of the cutting blade, and when cutting of the workpiece is performed, the cutting water is supplied from the nozzle to the cutting blade and the workpiece. To. In the cutting device, the workpiece is cut while the cutting chips and processing heat are removed by the cutting water.

In order to efficiently remove cutting chips and processing heat, the nozzle is preferably provided at a position very close to the cutting blade and the workpiece. Therefore, the nozzle is fixed to the cutting device so that the pipe portion of the nozzle having the linear pipe portion is along the side surface of the cutting blade and the surface of the workpiece. Further, in order to fix the nozzle in a predetermined position with high accuracy, a dedicated jig for finely adjusting the position of the nozzle may be used (see Patent Document 1).

Japanese Unexamined Patent Publication No. 2010-42490

However, when replacing the cutting blade, the nozzle may be fixed at the wrong height position, such as when the height position for fixing the nozzle is set incorrectly or when the nozzle is touched and the nozzle is moved. be. If the nozzle is fixed at an incorrect height position, the nozzle may collide with the workpiece when cutting the workpiece, and the nozzle or the workpiece may be damaged.

Conventionally, before cutting the workpiece, the user (operator) of the cutting device visually confirms whether or not the height position of the fixed nozzle is within the allowable range. In addition, the height position of the nozzle may be confirmed by the above-mentioned jig. However, it is troublesome to confirm the height position of the nozzle by these methods, and there are cases where an error in the height position of the nozzle cannot be detected when the deviation from the allowable range is small.

The present invention has been made in view of such a problem, and an object thereof is to easily and surely detect an error in the height position of a nozzle for supplying cutting water, and a workpiece due to a collision of the nozzles. It is to provide a cutting device and a nozzle height inspection method capable of preventing damage to the nozzle.

According to one aspect of the present invention, a cutting unit having a cutting blade for cutting a workpiece, a nozzle for supplying cutting water to the cutting blade, and a cutting unit provided below the cutting unit, the upper surface thereof as a holding surface. A nozzle height inspection method for inspecting the height of the nozzle in a cutting device extending along the side surface of the cutting blade to the front side or the rear side of the cutting blade. The jig piece fixing step for fixing the jig piece on the holding surface of the chuck table, and the cutting blade is lowered onto the upper surface of the jig piece to form the cutting blade and the jig piece. A reference position setting step that detects the contact of, and sets the height of the cutting unit when the contact is detected as a reference position, and the tip of the nozzle is located above the jig piece, and the The cutting unit is positioned so that the lower end of the cutting blade is located on the laterally outer side of the jig piece, and then the cutting unit is lowered to an inspection position a predetermined distance below the reference position. A contact determination step for determining whether or not the tool piece and the nozzle are in contact, and a height of the nozzle when it is determined in the contact determination step that the jig piece and the nozzle are in contact with each other. Provided is a nozzle height inspection method comprising a notification step for notifying that the nozzle is abnormal.

Preferably, in the reference position setting step, the contact between the cutting blade and the jig piece is detected by detecting the elastic wave generated at the time of contact between the cutting blade and the jig piece, and the contact is detected. In the contact determination step, when an elastic wave generated when the nozzle and the jig piece come into contact with each other is detected, it is determined that the nozzle and the jig piece are in contact with each other.

Further, preferably, in the reference position setting step, the contact between the cutting blade and the jig piece is detected by detecting the electrical conduction between the cutting blade and the jig piece. Then, in the contact determination step, when the electrical conduction between the nozzle and the jig piece is detected, it is determined that the nozzle and the jig piece are in contact with each other.

Further, according to another aspect of the present invention, a cutting unit having a cutting blade for cutting a workpiece, a nozzle for supplying cutting water to the cutting blade, and a cutting unit provided below the cutting unit and having an upper surface thereof. A chuck table serving as a holding surface, and a cutting edge detection unit for inserting the cutting blade between the light emitting portion and the light receiving portion to detect the position of the lower end of the cutting blade, and the nozzle is of the cutting blade. A nozzle height inspection method for inspecting the height of the nozzle in a cutting device extending to the front side or the rear side of the cutting blade along the side surface, wherein the cutting unit is lowered to detect the cutting edge of the cutting edge. A reference position positioning step in which the cutting blade is inserted between the light emitting portion and the light receiving portion and the lower end of the cutting blade is positioned at a reference position lower than the upper end of the cutting edge detection unit, and a determination lower than the reference position. A contact determination step for determining whether or not the cutting edge detection unit and the nozzle are in contact with each other when the cutting unit is further lowered so as to position the lower end of the cutting blade at a position, and the contact determination step. The nozzle height inspection method is characterized by comprising a notification step for notifying that the height of the nozzle is abnormal when it is determined that the nozzle has come into contact with the upper end of the cutting edge detection unit. Provided.

Preferably, in the contact determination step, when an elastic wave generated when the cutting edge detection unit and the nozzle come into contact with each other is detected, it is determined that the cutting edge detection unit and the nozzle are in contact with each other.

Further, preferably, in the contact determination step, when electrical continuity between the cutting edge detection unit and the nozzle is detected, it is determined that the cutting edge detection unit and the nozzle are in contact with each other. ..

According to still another aspect of the present invention, a cutting unit having a cutting blade for cutting a workpiece, a nozzle for supplying cutting water to the cutting blade, and a cutting unit provided below the cutting unit and having an upper surface thereof. Inspect the height of the nozzle, the cutting edge detection unit that lowers the cutting blade into the cutting blade entry groove between the light emitting part and the light receiving part, and detects the position of the lower end of the cutting blade, and the chuck table that serves as the holding surface. The nozzle height inspection unit is provided with a nozzle height inspection unit, and the nozzle height inspection unit detects electrical conduction between a jig piece or a cutting edge detection unit mounted on the chuck table and the nozzle. Provided is a cutting device comprising a contact detection circuit capable of detecting contact between a jig piece or the cutting edge detection unit and the nozzle.

In the nozzle height inspection method according to one aspect of the present invention, when the cutting unit provided with the cutting blade is lowered to a predetermined height position, whether or not the nozzle provided with the cutting unit comes into contact with a predetermined object is determined. judge. Here, the predetermined object is a jig piece or a cutting edge detection unit fixed to the chuck table.

When the cutting unit is lowered, the nozzle and the predetermined object do not collide as long as the height position of the nozzle is within the allowable range. On the other hand, when the nozzle is fixed at a height position below the allowable range, the nozzle and the predetermined object come into contact with each other. That is, when contact between the nozzle and the predetermined target is detected when the cutting unit is lowered, the nozzle is not fixed at the normal height position, and the height position of the nozzle is set. It can be determined that it is abnormal.

According to the nozzle height detection method according to one aspect of the present invention, it is possible to reliably detect the presence or absence of an error in the height position of the nozzle regardless of a method such as visual confirmation by a user of a cutting device or the like. In addition, it is possible to easily detect the presence or absence of an error in the height position of the nozzle simply by lowering the cutting unit. When an error in the height position is detected, damage to the workpiece due to the collision of the nozzle can be prevented by correcting the height position of the nozzle.

Therefore, according to one aspect of the present invention, an error in the height position of the nozzle that supplies cutting water can be easily and surely detected, and a cutting device and a nozzle height inspection that can prevent damage to the workpiece due to collision of the nozzles. The method is provided.

It is a perspective view which shows typically the cutting apparatus and the workpiece. It is a perspective view which shows the cutting unit in an enlarged manner. FIG. 3A is a side view schematically showing a cutting unit in which the nozzle is fixed at an allowable height position, and FIG. 3B is a side view in which the nozzle is not fixed in an allowable range. It is a side view which shows the cutting unit schematically. It is a side view which shows typically the structure of the nozzle height inspection unit. FIG. 5A is a side view schematically showing the cutting unit and the sub-chuck table in the reference position setting step, and FIG. 5B schematically shows the cutting unit and the sub-chuck table in the contact determination step. It is a side view. It is a side view which shows typically the cutting unit and the cutting edge detection unit. FIG. 7A is a side view schematically showing a cutting unit and a cutting edge detection unit in the reference position positioning step, and FIG. 7B schematically shows a cutting unit and a cutting edge detection unit in the contact determination step. It is a side view. FIG. 8A is a side view schematically showing a reference position setting step carried out using the AE sensor, and FIG. 8B schematically shows a contact determination step carried out using the AE sensor. It is a side view. FIG. 9A is a flowchart showing a flow of an example of the nozzle height inspection method, and FIG. 9B is a flowchart showing a flow of another example of the nozzle height inspection method.

An embodiment according to one aspect of the present invention will be described with reference to the accompanying drawings. First, with reference to FIG. 1, a cutting device on which the nozzle height inspection method according to the present embodiment is carried out and a workpiece to be cut by the cutting device will be described. FIG. 1 is a perspective view schematically showing a cutting device and a workpiece. The workpiece 1 is, for example, a material such as silicon, SiC (silicon carbide), or other semiconductor, or a substantially disk-shaped substrate made of a material such as sapphire, glass, or quartz.

The surface of the workpiece 1 is partitioned by a plurality of scheduled division lines arranged in a grid pattern, and devices such as ICs are formed in each of the partitioned regions. Finally, the workpiece 1 is divided along the planned division line to form individual device chips. For example, the workpiece 1 is held by the tape 3 attached to the annular frame 5, and is cut in the state of the frame unit 7 integrated with the frame 5 and the tape 3.

As shown in FIG. 1, the cutting device 2 includes a device base 4 that supports each component. At the upper center of the device base 4, there is an X-axis moving table 6, an X-axis moving mechanism that moves the X-axis moving table 6 in the X-axis direction (machining feed direction), and dust-proof and drip-proof that covers the X-axis moving mechanism. A cover (not shown) and a drainage channel 20 for receiving the liquid reaching the dust-proof and drip-proof cover are provided. The X-axis moving mechanism includes a pair of X-axis guide rails 12 parallel to the X-axis direction, and an X-axis moving table 6 is slidably attached to the X-axis guide rail 12.

A nut portion (not shown) is provided on the lower surface side of the X-axis moving table 6, and an X-axis ball screw 14 parallel to the X-axis guide rail 12 is screwed into the nut portion. An X-axis pulse motor 16 is connected to one end of the X-axis ball screw 14. When the X-axis ball screw 14 is rotated by the X-axis pulse motor 16, the X-axis moving table 6 moves in the X-axis direction along the X-axis guide rail 12.

A chuck table 8 for sucking and holding the workpiece 1 is provided on the X-axis moving table 6. The chuck table 8 is connected to a rotation drive source (not shown) such as a motor, and can rotate around a rotation axis perpendicular to the upper surface of the chuck table 8. Further, the chuck table 8 is fed in the X-axis direction by the X-axis moving mechanism described above.

The surface (upper surface) of the chuck table 8 is a holding surface 8a that sucks and holds the workpiece 1. The holding surface 8a is connected to a suction source (not shown) via a suction path (not shown) formed inside the chuck table 8. A clamp 10 for fixing the annular frame 5 for holding the workpiece 1 is arranged around the holding surface 8a via the tape 3.

On the upper surface of the apparatus base 4, a support structure 22 for supporting two cutting units 18 for cutting the workpiece 1 is arranged so as to straddle the X-axis moving mechanism. A cutting unit moving mechanism for moving the two cutting units 18 in the Y-axis direction (indexing feed direction) and the Z-axis direction, respectively, is provided on the upper part of the front surface of the support structure 22.

The cutting unit moving mechanism includes a pair of Y-axis guide rails 24 arranged in front of the support structure 22 and parallel to the Y-axis direction. Two Y-axis moving plates 26 corresponding to each of the cutting units 18 are slidably attached to the Y-axis guide rail 24. A nut portion (not shown) is provided on the back surface side (rear surface side) of each Y-axis moving plate 26, and a Y-axis ball screw 28 parallel to the Y-axis guide rail 24 is screwed on this nut portion. It has been combined.

A Y-axis pulse motor 28a is connected to one end of the Y-axis ball screw 28. When the Y-axis ball screw 28 is rotated by the Y-axis pulse motor 28a, the corresponding Y-axis moving plate 26 moves in the Y-axis direction along the Y-axis guide rail 24. A pair of Z-axis guide rails 30 parallel to the Z-axis direction are provided on the surface (front surface) of the Y-axis moving plate 26, respectively. A Z-axis moving plate 32 is slidably attached to each Z-axis guide rail 30.

A nut portion (not shown) is provided on the back surface side (rear surface side) of the Z-axis moving plate 32, and a Z-axis ball screw 34 parallel to the Z-axis guide rail 30 is screwed into this nut portion. ing. A Z-axis pulse motor 36 is connected to one end of the Z-axis ball screw 34. When the Z-axis ball screw 34 is rotated by the Z-axis pulse motor 36, the Z-axis moving plate 32 moves in the Z-axis direction (cutting feed direction) along the Z-axis guide rail 30.

At the lower part of each of the two Z-axis moving plates 32, a cutting unit 18 for processing the workpiece 1 and an imaging unit (camera) 38 capable of imaging the workpiece 1 held on the chuck table 8 are fixed. Has been done. If the Y-axis moving plate 26 is moved in the Y-axis direction, the cutting unit 18 and the imaging unit 38 are moved in the Y-axis direction (indexing feed direction), and if the Z-axis moving plate 32 is moved in the Z-axis direction, The cutting unit 18 and the imaging unit 38 move in the Z-axis direction (cutting feed direction).

The cutting unit 18 will be further described with reference to FIG. FIG. 2 is an enlarged perspective view of the cutting unit 18. The cutting unit 18 includes a cutting blade 18a and a spindle 40 on which the cutting blade 18a is mounted on the tip end side.

The cutting blade 18a has a disc-shaped base. A substantially circular mounting hole penetrating the base is provided in the central portion of the base, and the tip portion of the spindle 40 is passed through the mounting hole to fix the cutting blade 18a to the spindle 40. An annular cutting edge 18b for cutting into the workpiece 1 is fixed to the outer peripheral portion of the base. A spindle motor (not shown) for rotating the spindle 40 is mounted on the base end side of the spindle 40, and the spindle motor is housed in the spindle housing 42.

When the spindle motor housed in the spindle housing 42 is operated to rotate the spindle 40, the cutting blade 18a mounted on the tip of the spindle 40 rotates about the spindle 40 as an axis. When the cutting unit 18 is moved to a predetermined height position while the cutting blade 18a is rotated and the chuck table 8 held by the workpiece 1 is machined and fed along the X-axis direction, the rotating cutting blade 18a is cut. The workpiece 1 is cut when the blades 18b come into contact with each other.

When the workpiece 1 is cut by the cutting blade 18a, cutting chips derived from the workpiece 1 are generated and scattered around the workpiece 1 to contaminate the surface of the workpiece 1. Further, when the workpiece 1 is cut, machining heat is generated, and the machining heat may cause expansion or distortion of the cutting blade 18a or the workpiece 1 to reduce the accuracy of the cutting process. Therefore, while cutting the workpiece 1, cutting water such as pure water is supplied to the workpiece 1 and the cutting blade 18a.

The cutting unit 18 of the cutting device 2 includes a nozzle 44 for supplying cutting water and a cutting water supply unit 48 in the vicinity of the cutting blade 18a, and when the workpiece 1 is cut, the nozzle 44 and the cutting water are provided. Cutting water is supplied from the supply unit 48 to the cutting blade 18a and the workpiece 1. The cutting water supply unit 48 supplies the cutting water to the cutting blade 18a mainly from the machining feed direction (X-axis direction), and the nozzle 44 supplies the cutting water to the cutting blade 18a mainly from the side.

The nozzle 44 supports a pair of linear portions 44a extending in the machining feed direction along the side surface of the cutting blade 18a and the surface of the workpiece 1 and supporting the proximal ends of the pair of linear portions 44a. A part 44b and the like are provided. The tip of the pair of linear portions 44a projects forward or backward in the machining feed direction (X-axis direction) of the cutting blade 18a. Each of the pair of linear portions 44a is formed of a pipe-shaped member, and a plurality of spouts (not shown) facing the cutting blade 18a are formed.

Further, the support portion 44b of the nozzle 44 is fixed to the blade cover 46 that covers and protects the cutting blade 18a. The blade cover 46 includes an elliptical screw hole 46b through which a bolt 46a for fixing the support portion 44b is passed. The nozzle 44 is fixed to the cutting unit 18 by inserting the bolt 46a into the insertion hole (not shown) provided in the support portion 44b of the nozzle 44 and tightening the bolt 46a into the screw hole 46b.

The screw hole 46b is formed in an elliptical shape having a width corresponding to the diameter of the screw portion of the bolt 46a, and is formed to have a length larger than the diameter. Therefore, the fixing height of the bolt 46a in the screw hole 46b can be determined at an arbitrary position within the range of the length of the screw hole 46b. Then, the height of the nozzle 44 can be adjusted so that the cutting water can be efficiently supplied to the cutting blade 18a or the like in consideration of the thickness of the workpiece 1 or the tape 3.

At the upper end of the support portion 44b of the nozzle 44, a connection portion 44c to which a supply pipeline (not shown) of cutting water ejected from the linear portion 44a is connected is provided. When the cutting water is supplied from the cutting water supply source (not shown) to the nozzle 44 of the cutting unit 18 through the pipeline, the cutting water is supplied from the nozzle 44 to the cutting blade 18a and the workpiece 1.

Further, as shown in FIG. 1, the cutting device 2 further includes a control unit 56. The control unit 56 has a function of controlling each component of the cutting device 2 such as the cutting unit 18, the chuck table 8, each moving mechanism, and the image pickup unit 38. Further, the control unit 56 has a function of controlling the nozzle height inspection unit 58, which will be described later. The function of the control unit 56 is realized, for example, as software of a computer for controlling a device.

Further, on the front surface of the cutting device 2, a display unit 50 made of a display panel with a touch panel or the like is provided. The user or manager of the cutting device 2 can input information such as machining conditions into the control unit 56 using the touch panel. The display unit 50 displays an interface image for inputting information and operating the cutting device 2. In addition, the display unit 50 can display information on the operating status of the cutting device 2 and various warnings.

Further, an alarm lamp 52 electrically connected to the control unit 56 is arranged on the upper portion of the cutting device 2. The alarm lamp 52 has, for example, a green lamp and a red lamp. When the cutting device 2 is in a normal operating state, the control unit 56 lights the green lamp to notify the user or the manager that the cutting device 2 is normal. On the other hand, when a problem occurs in the cutting device 2, the control unit turns on a red lamp to notify the user or the manager to that effect.

Further, the cutting device 2 includes a cutting edge detection unit 54 that detects the height of the cutting edge 18b of the cutting blade 18a in the vicinity of the cutting unit 18. The cutting edge detection unit 54 detects the height of the cutting edge 18b of the cutting blade 18a immediately after the cutting blade 18a is mounted on the cutting unit 18 or after the workpiece 1 is repeatedly cut and worn. Then, the cutting device 2 raises the cutting unit 18 based on the height of the cutting edge 18b detected by the cutting edge detection unit 54 so that the lower end of the cutting edge 18b becomes a predetermined height when the workpiece 1 is cut. Adjust the height.

The cutting edge detection unit 54 has a cover portion that can be opened and closed, and the cover portion is closed while the workpiece 1 is being cut by the cutting blade 18a, and each component of the cutting edge detection unit 54 is attached to the cover portion. Be housed. While cutting the workpiece 1 is being performed, the cutting fluid is supplied to the cutting blade 18a and the workpiece 1 from the nozzle 44 and the like, and the cutting fluid containing the cutting chips generated from the workpiece 1 is scattered around. .. The cutting water is also scattered on the cutting edge detection unit 54, but when the cover portion is closed, the cutting fluid does not adhere to each component of the cutting edge detection unit 54.

When the cutting edge detection unit 54 detects the height of the cutting edge 18b of the cutting blade 18a, the cover portion is opened. Each configuration of the cutting edge detection unit 54 will be described with reference to FIG. FIG. 6 schematically shows a side view of the inside of the cutting edge detection unit 54. The main body of the cutting edge detection unit 54 is provided with a cutting blade entry groove 54c opened upward, and when detecting the height position of the lower end of the cutting blade 18b of the cutting blade 18a, the cutting blade is provided in the cutting blade entry groove 54c. Let 18a enter.

A light emitting portion 54a is provided on one side wall of the cutting blade entry groove 54c, and a light receiving portion 54b is provided on the other side wall of the cutting blade entry groove 54c at a position facing the light emitting portion 54a. The light emitting unit 54a and the light receiving unit 54b are provided at substantially the same height position. A light source 68a is connected to the light emitting unit 54a via an optical fiber or the like, and when the light source 68a is operated, light is emitted from the light emitting unit 54a.

A photoelectric conversion unit 68b is connected to the light receiving unit 54b via an optical fiber or the like, and the light that reaches the light receiving unit 54b is received by the photoelectric conversion unit 68b. An optical sensor is incorporated in the photoelectric conversion unit 68b, and an electric signal (for example, voltage) corresponding to the amount of received light is output from the photoelectric conversion unit 68b. The photoelectric conversion unit 68b is electrically connected to the end position detection unit 68c, and transmits the electric signal to the end position detection unit 68c.

The end position detecting unit 68c is connected to a cutting feed unit 36a composed of a Z-axis guide rail 30, a Z-axis moving plate 32, a Z-axis ball screw 34, and a Z-axis pulse motor 36, and is connected to a cutting unit 18. You can control the height of the. Further, information regarding the height position of the cutting unit 18 can be received from the cutting feed unit 36a.

When the cutting edge detection unit 54 detects the height of the cutting edge 18b of the cutting blade 18a, the light source 68a is operated to radiate light from the light emitting unit 54a, and the light is received by the light receiving unit 54b. When the cutting blade 18a is lowered toward the cutting blade approach groove 54c, the light radiated from the light emitting portion 54a is gradually blocked by the cutting blade 18a, and the light received by reaching the light receiving portion 54b is received. The amount gradually decreases.

Therefore, by analyzing the electric signal output from the photoelectric conversion unit 68b with the end position detection unit 68c, the height position of the lower end of the cutting blade 18b of the cutting blade 18a can be detected. Then, the height of the cutting unit 18 when the height of the lower end of the cutting blade 18b of the cutting blade 18a becomes a height position suitable for cutting the workpiece 1 is recorded in the control unit 56. As a result, when cutting the workpiece 1, the cutting unit 18 can be positioned at the height position.

Further, the cutting device 2 includes a sub-chuck table 8b (see FIG. 4) in the vicinity of the chuck table 8. The sub-chuck table 8b is fixed on the X-axis moving table 6 like the chuck table 8, and by moving the X-axis moving table 6 in the X-axis direction (machining feed direction), the sub-chuck table 8b is moved in the X-axis direction together with the chuck table 8. You can move. Further, the sub-chuck table 8b is provided with a suction mechanism for sucking and holding the object to be held on the holding surface which is the upper surface.

When a plurality of workpieces 1 are cut by the cutting blade 18a mounted on the cutting unit 18, the cutting edge 18b of the cutting blade 18a is worn and the abrasive grains contained in the cutting edge 18b are not properly exposed from the binder. The state is reached, and the cutting ability of the cutting blade 18a is reduced. The unused cutting blade 18a is also not suitable for cutting as it is because the abrasive grains are not appropriately exposed. Therefore, a process called dressing is performed in which the cutting blade 18a is appropriately consumed and the abrasive grains are appropriately exposed from the binder of the cutting blade 18b.

When the cutting blade 18a to be dressed is rotated and the cutting blade 18a cuts a plate-shaped object called a dressing board, the abrasive grains of the cutting blade 18b are appropriately exposed and the cutting ability of the cutting blade 18a is improved. can. There are a plurality of types of dressing boards used for dressing, and an appropriate dressing board is selected and used according to the type of the cutting blade 18a. The dressing board used for dressing is, for example, sucked and held on the holding surface of the sub-chuck table 8b.

By the way, the nozzle 44 of the cutting unit 18 is fixed to the blade cover 46 at a predetermined height as described above. However, there are cases where the user of the cutting device 2 or the like makes a mistake in setting the fixed height of the nozzle 44, or when the cutting blade 18a is replaced, the nozzle 44 may be touched and the position of the nozzle 44 may be displaced. In addition, fixing is inappropriate, and the nozzle 44 may be fixed in an inclined state. If the nozzle 44 is not properly fixed as described above, the nozzle 44 may collide with the workpiece 1 when the workpiece 1 is cut, and the workpiece 1 may be damaged.

FIG. 3A is a side view schematically showing a cutting unit 18 in which the nozzle 44 is fixed at an allowable height position. The allowable range of the height position of the nozzle 44 is set with reference to, for example, the height position 64a of the lower end of the cutting edge 18b of the cutting blade 18a, and for example, the lower limit height position 64b thereof is the height position 64a. The height position is 1 mm to 2 mm higher than that. For example, the nozzle 44 is fixed to the cutting unit 18 so that the linear portion 44a of the nozzle 44 is higher than the lower limit height position 64b.

FIG. 3B is a side view schematically showing a cutting unit 18 in which the nozzle 44 is not fixed at an allowable height position. As shown in FIG. 3B, when the linear portion 44a of the nozzle 44 is lower than the lower limit height position 64b due to the nozzle 44 being fixed in an inclined state or the like, it is processed by the cutting blade 18a as it is. When the object 1 is cut, the nozzle 44 collides with the workpiece 1.

Therefore, the cutting device 2 is provided with a nozzle height inspection unit. Next, the nozzle height inspection unit will be described. The nozzle height inspection unit determines whether or not the height of the nozzle 44 fixed to the cutting unit 18 is appropriate. FIG. 4 is a configuration diagram schematically illustrating a part of the configuration of the nozzle height inspection unit 58. FIG. 4 shows a side view of the cutting unit 18, a cross-sectional view of the chuck table 8, a side view of the sub-chuck table 8b, and a circuit diagram.

The nozzle height inspection unit 58 includes, for example, a contact detection unit 60 and a contact detection circuit 62 including the contact detection unit 60. The contact detection circuit 62 has, for example, a power supply 62d, a switch 62a, the contact detection unit 60, and a switch 62b, which are connected in series.

One end of the contact detection unit 60 is electrically connected to the chuck table 8 and the sub-chuck table 8b via the switch 62a and the power supply 62d, and the other end is connected to the nozzle 44 of the cutting unit 18 via the switch 62b. It is electrically connected. Further, the other end of the contact detection unit 60 is electrically connected to the cutting blade 18a via the switch 62c and the spindle 40.

When inspecting the height of the nozzle 44 by the nozzle height inspection unit 58, the jig piece 66 is directly placed on the holding surface of the chuck table of either the chuck table 8 or the sub-chuck table 8b, and the jig piece 66 is cured on the chuck table. The tool piece 66 is sucked and held. Hereinafter, as shown in FIG. 4, a case where the chuck table for sucking and holding the jig piece 66 is a sub-chuck table 8b will be described as an example, but the jig piece 66 may be sucked and held by either chuck table.

The jig piece 66 is a member made of a conductive and rigid material such as stainless steel or carbon, and has an upper surface and a lower surface which are flat and parallel to each other. The jig piece 66 is between the height position 64a of the lower end of the cutting edge 18b of the cutting blade 18a and the lower limit height position 64b of the allowable range of the height position of the nozzle 44 with respect to the height position 64a. It is said that the thickness is larger than the distance of.

The nozzle height inspection unit 58 can determine the presence or absence of contact between the jig piece 66 and the cutting blade 18a by detecting the presence or absence of electrical continuity between the jig piece 66 and the cutting blade 18a. .. Further, the nozzle height inspection unit 58 can determine the presence or absence of contact between the jig piece 66 and the nozzle 44 by detecting the presence or absence of electrical continuity between the jig piece 66 and the nozzle 44. ..

The nozzle height inspection unit 58 further includes a notification unit for notifying that the position of the nozzle 44 in the height direction is abnormal. For example, the notification unit is the display unit 50, and when an abnormality in the height position of the nozzle 44 is detected, a warning image for notifying the abnormality is displayed on the display unit 50. Alternatively, the notification unit is an alarm lamp 52, and when an abnormality in the height position of the nozzle 44 is detected, the red lamp is turned on. Alternatively, the cutting device 2 may have a buzzer (not shown) that emits a warning sound when an abnormality in the position of the nozzle 44 is detected as a notification unit.

Next, the nozzle height inspection method according to one aspect of the present embodiment will be described. FIG. 9A is a flowchart showing the flow of the nozzle height inspection method according to one embodiment of the present embodiment. In the nozzle height inspection method, first, a jig piece fixing step S11 for fixing the jig piece 66 on the holding surface of the chuck table of either the chuck table 8 or the sub-chuck table 8b is performed.

For example, in the jig piece fixing step S11, as shown in FIG. 4, the jig piece 66 is placed on the holding surface of the sub-chuck table 8b, and the suction holding mechanism of the sub-chuck table 8b is operated to sub-subchrate the jig piece 66. The chuck table 8b is sucked and held.

In the nozzle height inspection method, next, a reference position setting step S12 for setting a reference position for the height of the cutting unit 18 is performed. In the reference position setting step S12, a reference position that is the reference height of the cutting unit 18 when determining the presence or absence of an abnormality in the height of the nozzle 44 is set. Here, the reference position is the height of the cutting unit 18 in the height direction (Z-axis direction, cutting feed direction) when the height position of the lower end of the cutting blade 18a is the height position of the upper surface of the jig piece 66. It is the position.

In the reference position setting step S12, first, the X-axis moving table 6 is moved so as to position the jig piece 66 below the cutting blade 18a, and the sub-chuck table 8b holding the jig piece 66 is moved. Next, the cutting unit 18 is lowered so as to bring the cutting blade 18a into contact with the upper surface of the jig piece 66. At this time, the contact between the cutting blade 18a and the jig piece 66 is detected by, for example, the contact detection unit 60 provided in the contact detection circuit 62 of the nozzle height inspection unit 58.

When the contact between the cutting blade 18a and the jig piece 66 is detected, as shown in FIG. 5A, the switch 62a and the switch 62c of the contact detection circuit 62 are switched on and the switch 62b is switched off in advance. back. FIG. 5A is a side view schematically showing the reference position setting step S12, and FIG. 5A shows a circuit diagram of the contact detection circuit 62.

As shown in FIG. 5A, when the cutting blade 18a and the jig piece 66 come into contact with each other and become conductive, a current is generated in the contact detection circuit 62, and the current is observed by the contact detection unit 60. That is, when the current of the contact detection circuit 62 is observed by the contact detection unit 60, the contact between the cutting blade 18a and the jig piece 66 is detected. Then, in the reference position setting step S12, the height of the cutting unit 18 when the contact is detected is set as the reference position.

In the nozzle height inspection method, the contact determination step S13 is then carried out. In the contact determination step S13, first, the tip of the linear portion 44a of the nozzle 44 is located above the jig piece 66, and the lower end of the cutting blade 18b of the cutting blade 18a is located outside the jig piece 66 in the horizontal direction. Position the cutting unit 18 so that it does. At this time, the X-axis moving table 6, the Y-axis moving plate 26, and the Z-axis moving plate 32 are moved.

In the contact determination step S13, the cutting unit is then lowered to an inspection position that is a predetermined distance below the above-mentioned reference position. Here, the predetermined distance is, for example, a range of allowable distances in the height direction between the height position of the lower end of the cutting edge 18b of the cutting blade 18a and the height position of the linear portion 44a of the nozzle 44. Is the lower limit of.

When the contact determination step S13 is performed, the switch 62a and the switch 62b of the contact detection circuit 62 are switched on and the switch 62c is switched off in advance. FIG. 5B is a side view schematically showing the contact determination step S13, and shows a circuit diagram of the contact detection circuit 62.

A case where the nozzle 44 is appropriately fixed to the cutting unit 18 and the height position of the lower end of the cutting blade 18a and the linear portion 44a of the nozzle 44 in the height direction are within an allowable range will be described. .. In this case, when the cutting unit 18 is lowered to the inspection position below the reference position by the predetermined distance, the linear portion 44a of the nozzle 44 and the jig piece 66 do not come into contact with each other, and electricity is provided between the two. Does not conduct. Therefore, no current is generated in the contact detection circuit 62, and the contact detection unit 60 does not detect the current.

Next, the nozzle 44 is not properly fixed to the cutting unit 18, and the height position of the lower end of the cutting blade 18a and the linear portion 44a of the nozzle 44 in the height direction are allowed. The case of falling below the range will be described. In this case, when the cutting unit 18 is lowered to the inspection position, the linear portion 44a of the nozzle 44 and the jig piece 66 come into contact with each other and electrically conduct between them. Therefore, a current is generated in the contact detection circuit 62, and the contact detection unit 60 detects the current.

That is, when the cutting unit 18 is lowered from the reference position to the inspection position and the contact detection unit 60 of the nozzle height inspection unit 58 does not detect the current of the contact detection circuit 62, the jig piece 66 and the nozzle 44 And can be determined not to be in contact. On the other hand, when the contact detection unit 60 of the nozzle height inspection unit 58 detects the current of the contact detection circuit 62, it can be determined that the jig piece 66 and the nozzle 44 are in contact with each other.

When it is determined that the jig piece 66 and the nozzle 44 are in contact with each other, it is confirmed that the nozzle 44 is not fixed at an appropriate position and the height is abnormal. Therefore, when the contact determination step S13 is performed and it is determined that the jig piece 66 and the nozzle 44 are in contact with each other, the notification step S14 for notifying that the height of the nozzle 44 is abnormal is then performed. do.

In the notification step S14, the notification unit such as the display unit 50 of the cutting device 2 or the alarm lamp 52 notifies that the position of the nozzle 44 is abnormal. When the manager or user of the cutting device 2 confirms the warning issued by the notification unit, the manager or the like confirms the fixing status of the nozzle 44 of the cutting device 2 to the cutting unit 18, and the height of the nozzle 44 is high. The position and the like may be adjusted.

The inspection of the height position of the nozzle 44 can also be performed by using the cutting edge detection unit 54 without using the jig piece 66 held by the chuck table. In this case, the nozzle height inspection unit 58 includes a cutting edge detection unit 54. Next, the nozzle height inspection method according to another aspect of the present embodiment will be described. FIG. 9B is a flowchart showing the flow of the nozzle height inspection method according to another aspect of the present embodiment.

As shown in FIG. 9B, in the nozzle height inspection method, first, the reference positioning step S21 for positioning the lower end of the cutting edge 18b of the cutting blade 18a at the reference position is carried out. FIG. 7A is a side view schematically showing the reference position positioning step S21. FIG. 7A shows an example of the reference position 70.

The reference position 70 serves as a height reference in the nozzle height inspection method. The reference position 70 is set at a height lower than the upper end of the main body of the cutting edge detection unit 54 in the cutting blade approach groove 54c of the cutting edge detection unit 54. The reference position 70 is a height position where the cutting edge detection unit 54 can detect that the lower end of the cutting edge 18b of the cutting blade 18a has reached the reference position 70.

The distance between the reference position 70 and the height position of the upper end of the main body of the cutting edge detection unit 54 in the cutting feed direction (Z-axis direction, height direction) will be described. The distance is smaller than the distance in the cutting feed direction between the lower limit of the allowable range of the height position of the nozzle 44 with respect to the lower end of the cutting blade 18a and the lower end of the cutting blade 18a.

In the reference position positioning step S21, the cutting unit 18 is lowered to be between the light emitting portion 54a (see FIG. 6) and the light receiving portion 54b (see FIG. 6) inside the cutting blade approach groove 54c of the cutting edge detection unit 54. The cutting blade 18a is made to enter the cutting blade entry groove 54c (see FIG. 6). Then, the cutting unit 18 is lowered until the lower end of the cutting blade 18b of the cutting blade 18a reaches the reference position 70.

Next, in the nozzle height inspection method according to another aspect of the present embodiment, contact for determining whether or not the cutting edge detection unit 54 and the nozzle 44 are in contact with each other when the cutting unit 18 is further lowered. The determination step S22 is carried out. FIG. 7B is a side view schematically showing the contact determination step S22. FIG. 7B shows an example of the determination position 72. Whether or not the cutting edge detection unit 54 and the nozzle 44 are in contact with each other is determined by the contact detection circuit 62 shown in FIGS. 7A and 7B.

The contact detection unit 60 is electrically connected to the cutting edge detection unit 54 via the switch 62a and the power supply 62d. When the nozzle 44 of the cutting unit 18 and the main body of the cutting edge detection unit 54 come into contact with each other, the two are electrically connected to generate a current in the contact detection circuit 62, and the current is observed by the contact detection unit 60. Therefore, the contact detection unit 60 can determine whether or not they are in contact with each other by detecting the presence or absence of electrical continuity between the main body of the cutting edge detection unit 54 and the linear portion 44a of the nozzle 44.

In the contact determination step S22, the cutting unit 18 is lowered so as to position the lower end of the cutting blade 18b of the cutting blade 18a at the determination position 72 lower than the reference position 70. The cutting edge detection unit 54 detects that the lower end of the cutting edge 18b of the cutting blade 18a has reached the determination position 72 when the cutting unit 18 is lowered. Then, when the end position detecting unit 68c detects that the lower end of the cutting blade 18b of the cutting blade 18a has reached the determination position 72, the lowering of the cutting unit 18 is stopped. Here, the determination position 72 will be described.

The determination position 72 is the main body of the cutting edge detection unit 54 by the distance between the lower limit of the allowable range of the height position of the linear portion 44a of the nozzle 44 with respect to the lower end of the cutting blade 18a and the lower end of the cutting blade 18a. It is set at a height lower than the top edge. In this case, the sum of the height position of the upper end of the cutting edge detection unit 54, the reference position 70, the distance in the cutting feed direction (height direction), the reference position 70, and the determination position 72 in that direction is , The lower limit of the allowable distance between the lower end of the cutting blade 18a and the nozzle 44.

The nozzle 44 is appropriately fixed to the cutting unit 18, and the distance between the height position of the lower end of the cutting blade 18a and the linear portion 44a of the nozzle 44 in the cutting feed direction (height direction) is within an allowable range. The case where it fits will be described. In this case, when the cutting unit 18 is lowered, the linear portion 44a of the nozzle 44 and the main body of the cutting edge detection unit 54 do not come into contact with each other, and the two do not electrically conduct with each other. Therefore, no current is generated in the contact detection circuit 62, and the contact detection unit 60 does not detect the current.

Next, the nozzle 44 is not properly fixed to the cutting unit 18, and the height position of the lower end of the cutting blade 18a and the linear portion 44a of the nozzle 44 in the height direction are allowed. The case of falling below the range will be described. In this case, when the cutting unit 18 is lowered, the linear portion 44a of the nozzle 44 and the main body of the cutting edge detection unit 54 come into contact with each other and electrically conduct between them. Therefore, a current is generated in the contact detection circuit 62, and the contact detection unit 60 detects the current.

That is, when the cutting unit 18 is lowered so as to position the lower end of the cutting edge 18b of the cutting blade 18a at the determination position 72 and the contact detection unit 60 does not detect the current of the contact detection circuit 62, the cutting edge detection unit 54 and the cutting edge detection unit 54. It is determined that the nozzle 44 and the nozzle 44 are not in contact with each other. On the other hand, when the contact detection unit 60 detects the current of the contact detection circuit 62, it is determined that the cutting edge detection unit 54 and the nozzle 44 are in contact with each other.

When it is determined that the cutting edge detection unit 54 and the nozzle 44 are in contact with each other, the nozzle 44 is not properly fixed and the height position of the nozzle 44 relative to the lower end of the cutting edge 18b of the cutting blade 18a is set. It is confirmed that it is abnormal. Therefore, when the contact determination step S22 is performed and it is determined that the nozzle 44 has come into contact with the upper end of the cutting edge detection unit 54, then the notification step S23 for notifying that the height of the nozzle 44 is abnormal is performed. .. The notification step S23 is the same as the above-mentioned notification step S14.

As described above, according to the method for detecting the height of the nozzle 44 according to the other aspect according to the present embodiment, the height position of the nozzle 44 does not depend on the method such as visual confirmation by the user or the like of the cutting device 2. The presence or absence of an error can be reliably detected.

In the above embodiment, the jig piece 66 or the cutting edge detection unit 54 detects the electrical conduction when the jig piece 66 or the cutting edge detection unit 54 and the nozzle 44 come into contact with each other by the contact detection unit 60. And the case of detecting the contact with the nozzle 44 has been described. However, the nozzle height inspection method according to one aspect of the present invention is not limited to this. That is, the contact may be detected by another method.

For example, as shown in FIG. 8A, the sub-chuck table 8b of the cutting device 2 may be provided with an AE (Acoustic Emission) sensor 74 for detecting elastic waves as a component of the nozzle height inspection unit. .. FIG. 8A is a side view schematically showing another example of the reference position setting step S12. The nozzle height inspection unit includes an AE sensor 74 fixed to the sub-chuck table 8b and a contact detection unit 76 electrically connected to the AE sensor 74.

In the reference position setting step S12, when the cutting blade 18a and the jig piece 66 come into contact with each other when the cutting unit 18 is lowered, an elastic wave is generated by the impact, and the elastic wave is detected by the AE sensor 74. The contact detection unit 76 detects contact between the cutting blade 18a and the jig piece 66 when an elastic wave is detected by the AE sensor 74.

Further, in the contact determination step S13, when the AE sensor 74 detects an elastic wave generated when the nozzle 44 and the jig piece 66 come into contact with each other when the cutting unit 18 is lowered to the inspection position, both are used. Is determined to have contacted.

Further, for example, as shown in FIG. 8B, the cutting edge detection unit 54 may be provided with an AE sensor 74 for detecting elastic waves. FIG. 8B is a side view schematically showing another example of the contact determination step S22. A contact detection unit 76 is electrically connected to the AE sensor 74. In the contact determination step S22, when the elastic wave generated when the cutting edge detection unit 54 and the nozzle 44 come into contact with each other is detected by the AE sensor 74, it is determined that they are in contact with each other.

Further, in the above embodiment, the presence / absence of contact between the tip of the linear portion 44a of the nozzle 44 and the jig piece 66 is detected to determine the presence / absence of an abnormality in the position of the nozzle 44 in the height direction. , One aspect of the present invention is not limited to this. In one aspect of the present invention, the determination may be performed by detecting the presence or absence of contact between the proximal end side of the linear portion 44a of the nozzle 44 and the jig piece 66.

Further, in the contact determination step S13, after or before detecting the presence or absence of contact with the jig piece 66 when the cutting unit 18 is lowered with respect to the tip of the linear portion 44a of the nozzle 44, the base of the linear portion 44a. The presence or absence of contact may be detected for the edges in the same manner. In this way, when the presence or absence of contact with the jig piece 66 when the cutting unit 18 is lowered at both the tip end and the base end of the linear portion 44a is detected, the abnormality in the position of the nozzle 44 in the height direction becomes more abnormal. It can be detected in detail, and the inclination of the nozzle 44 can be evaluated.

In this case, in the contact determination step S13, it is necessary to detect the presence or absence of contact between the nozzle 44 and the jig piece 66 twice in total, which increases the time and effort required to perform the contact determination step 13. Therefore, a jig piece 66 longer than the linear portion 44a of the nozzle 44 may be used. That is, before lowering the cutting unit 18, the cutting unit 18 is positioned so that both the tip and the base end of the linear portion 44a of the nozzle 44 are located above the jig piece 66, and then the cutting unit 18 is lowered. The presence or absence of the contact is detected.

When the jig piece 66 longer than the linear portion 44a of the nozzle 44 is used, the presence or absence of contact between the nozzle 44 and the jig piece 66 is detected only once, and the position of the nozzle 44 in the height direction is abnormal. Can be detected in more detail, and the inclination of the nozzle 44 can be evaluated. That is, in either case, the nozzle 44 is tilted so that the tip end side of the linear portion 44a faces downward, or the nozzle 44 tilts so that the proximal end side of the linear portion 44a faces downward. Abnormal height can be easily detected.

In addition, the structure, method, and the like according to the above-described embodiment can be appropriately modified and implemented as long as they do not deviate from the scope of the object of the present invention.

1 Work piece 3 Tape 5 Frame 7 Frame unit 2 Cutting device 4 Device base 6 X-axis moving table 8 Chuck table 8a Holding surface 8b Sub-chuck table 10 Clamp 12, 24, 30 Guide rail 14, 28, 34 Ball screw 16 , 28a, 36 Pulse motor 36a Cutting feed unit 18 Cutting unit 18a Cutting blade 18b Cutting blade 20 Drainage channel 22 Support structure 26, 32 Moving plate 38 Imaging unit (camera)
40 Spindle 42 Spindle Jig 44 Nozzle 44a Linear part 44b Support part 44c Water supply port 46 Blade cover 46a Fixing bolt 46b Screw hole 48 Cutting water supply part 50 Display part 52 Alarm lamp 54 Cutting edge detection unit 54a Light source part 54b Light receiving part 54c Cutting blade Approach groove 56 Control unit 58 Nozzle height inspection unit 60,76 Contact detection unit 62 Contact detection circuit 62a, 62b, 62c Switch 62d Power supply 64a Height position 66 Jig piece 68a Light source 68b Photoelectric conversion unit 68c End position detection unit 70 Reference position 72 Judgment position 74 AE sensor

Claims (7)

A cutting unit having a cutting blade for cutting a workpiece and a nozzle for supplying cutting water to the cutting blade.
A chuck table provided below the cutting unit and having an upper surface as a holding surface is provided.
The nozzle is a nozzle height inspection method for inspecting the height of the nozzle in a cutting device extending to the front side or the rear side of the cutting blade along the side surface of the cutting blade.
A jig piece fixing step for fixing the jig piece on the holding surface of the chuck table,
The cutting blade is lowered onto the upper surface of the jig piece, the contact between the cutting blade and the jig piece is detected, and the height of the cutting unit when the contact is detected is set as a reference position. Reference position setting step and
The cutting unit is positioned so that the tip of the nozzle is located above the jig piece and the lower end of the cutting blade is located outside the jig piece in the horizontal direction, and then a predetermined distance from the reference position. A contact determination step for determining whether or not the jig piece and the nozzle are in contact with each other when the cutting unit is lowered to the lower inspection position.
When it is determined in the contact determination step that the jig piece and the nozzle are in contact with each other, a notification step for notifying that the height of the nozzle is abnormal and a notification step.
Nozzle height inspection method characterized by providing. In the reference position setting step, the contact between the cutting blade and the jig piece is detected by detecting the elastic wave generated at the time of contact between the cutting blade and the jig piece.
The contact determination step is characterized in that when an elastic wave generated when the nozzle and the jig piece come into contact with each other is detected, it is determined that the nozzle and the jig piece are in contact with each other. The nozzle height inspection method according to claim 1. In the reference position setting step, the contact between the cutting blade and the jig piece is detected by detecting the electrical conduction between the cutting blade and the jig piece.
The contact determination step is characterized in that when electrical continuity between the nozzle and the jig piece is detected, it is determined that the nozzle and the jig piece are in contact with each other. The nozzle height inspection method according to claim 1. A cutting unit having a cutting blade for cutting a workpiece and a nozzle for supplying cutting water to the cutting blade.
A chuck table provided below the cutting unit and having an upper surface as a holding surface,
A cutting edge detection unit for inserting the cutting blade between the light emitting unit and the light receiving unit and detecting the position of the lower end of the cutting blade is provided.
The nozzle is a nozzle height inspection method for inspecting the height of the nozzle in a cutting device extending to the front side or the rear side of the cutting blade along the side surface of the cutting blade.
A reference for lowering the cutting unit to allow the cutting blade to enter between the light emitting portion and the light receiving portion of the cutting edge detection unit, and positioning the lower end of the cutting blade at a reference position lower than the upper end of the cutting edge detection unit. Positioning step and
Contact determination to determine whether or not the cutting edge detection unit and the nozzle are in contact when the cutting unit is further lowered so as to position the lower end of the cutting blade at a determination position lower than the reference position. Steps and
The nozzle height is characterized by comprising a notification step for notifying that the height of the nozzle is abnormal when it is determined in the contact determination step that the nozzle has come into contact with the upper end of the cutting edge detection unit. Inspection method. The contact determination step is characterized in that when an elastic wave generated when the cutting edge detection unit and the nozzle come into contact with each other is detected, it is determined that the cutting edge detection unit and the nozzle are in contact with each other. The nozzle height inspection method according to claim 4. The contact determination step is characterized in that when electrical continuity between the cutting edge detection unit and the nozzle is detected, it is determined that the cutting edge detection unit and the nozzle are in contact with each other. The nozzle height inspection method according to claim 4. A cutting unit having a cutting blade for cutting a workpiece and a nozzle for supplying cutting water to the cutting blade.
A chuck table provided below the cutting unit and having an upper surface as a holding surface,
A cutting edge detection unit that lowers the cutting blade into the cutting blade entry groove between the light emitting part and the light receiving part and detects the position of the lower end of the cutting blade.
A nozzle height inspection unit for inspecting the height of the nozzle is provided.
The nozzle height inspection unit includes the jig piece or the cutting edge detection unit and the cutting edge detection unit by detecting electrical continuity between the jig piece or the cutting edge detection unit mounted on the chuck table and the nozzle. A cutting device including a contact detection circuit capable of detecting contact with a nozzle.

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