JP2018196920A - Cutting device - Google Patents

Abstract

A cutting edge detection unit determines whether a setup process of a contaminated cutting device can be performed. A cutting edge detection unit emits light from a light emitting unit in a state in which a cutting blade has entered between a light emitting unit and a light receiving unit, and the light is emitted to the light receiving unit without being blocked by the cutting blade. It has a cutting edge detection function that receives the arriving light and detects the position of the lower end of the cutting edge of the cutting blade in the cutting direction from the amount of light received, in a state where the cutting blade has not entered between the light emitting unit and the light receiving unit. A light-receiving amount determining unit 54 that determines whether the light-receiving amount of light received by the light-receiving unit has reached a threshold, and a light-receiving amount determining unit that determines that the light receiving amount of the light has not reached the threshold. A blade edge detection possibility determination unit 56 that detects a relationship between the position of the cutting blade in the cutting feed direction and the amount of light that reaches the light receiving unit and determines whether the blade edge detection unit can perform the blade edge detection function. , Obtain. [Selection] Figure 2

Description

  The present invention relates to a cutting apparatus for cutting a workpiece such as a semiconductor wafer, a package substrate, a ceramic substrate, or a glass substrate.

  A surface of a semiconductor wafer, a package substrate, a ceramic substrate, a glass substrate, or the like is partitioned by a plurality of division lines arranged in a lattice shape, and a device such as an IC is formed in each partitioned region. When a workpiece such as a semiconductor wafer or a substrate is finally divided along the planned division lines, individual device chips are formed.

  A cutting device having an annular cutting blade is used to divide the workpiece. In the cutting apparatus, the cutting blade is rotated in a plane perpendicular to the surface of the workpiece, the rotating cutting blade is positioned at a predetermined height position, and the workpiece is in a direction along the scheduled division line. Cutting is carried out by feeding to the machine.

  When cutting a workpiece using the cutting blade, it is important to position the cutting blade so that the lower end of the cutting edge of the cutting blade is at an appropriate height position. In the cutting apparatus, the holding surface of the chuck table that holds the workpiece is set as a reference position for the height of the lower end of the cutting edge. When performing the cutting process, a setup process is performed in which the lower end of the cutting edge of the cutting blade is aligned with the reference position.

  By the way, when cutting is repeatedly performed in the cutting apparatus, the annular cutting blade is gradually consumed, and the diameter of the cutting blade is reduced. Then, the height of the lower end of the cutting edge of the cutting blade is gradually shifted from the reference position. Therefore, a setup process is appropriately performed while cutting is repeatedly performed.

  Conventionally, the setup process is performed by gradually lowering the cutting blade while rotating the cutting blade to slightly cut the chuck table and detecting contact between the cutting blade and the chuck table. However, since the cutting blade cuts the chuck table every time the setup process is performed, the cutting edge of the cutting blade is clogged or crushed, resulting in a problem that the cutting ability of the cutting blade is reduced. Therefore, a non-contact setup process has been devised (see Patent Document 1).

  In the cutting apparatus that performs the non-contact type setup process, a blade edge detection unit is disposed in the vicinity of the chuck table. The main body of the cutting edge detection unit is provided with a cutting blade entry groove that opens upward. When detecting the height position of the lower end of the cutting edge of the cutting blade, the cutting blade enters the cutting blade entry groove.

  A light emitting portion is provided on one side wall of the cutting blade entering groove, and a light receiving portion is provided on the other side wall of the cutting blade entering groove at a position facing the light emitting portion with the cutting blade entering groove interposed therebetween. The light emitting unit is connected to a light source via an optical fiber or the like, and light is emitted from the light emitting unit when the light source is activated. A photoelectric conversion unit is connected to the light receiving unit via an optical fiber or the like, and light reaching the light receiving unit is received by the photoelectric conversion unit. Then, an electrical signal or the like corresponding to the amount of received light is output from the photoelectric conversion unit.

  The light emitting unit and the light receiving unit are provided at substantially the same height. The height position is a height position near the lower end of the cutting edge of the cutting blade when the cutting blade is positioned at a predetermined height position in the setup process.

  In the non-contact type setup process, the light source of the blade edge detection unit is operated to emit light from the light emitting unit toward the light receiving unit, and the light reaching the light receiving unit is received by the photoelectric conversion unit and converted into an electrical signal. Convert. Then, the cutting blade is caused to enter the cutting blade entry groove in a state where light is emitted from the light receiving portion.

  Then, since a part of the light emitted from the light emitting unit is blocked by the cutting blade, the amount of light received by the photoelectric conversion unit is reduced. Since the amount of light blocked by the cutting blade varies depending on the height position of the cutting blade, the height position of the cutting blade can be detected from the received light amount. Therefore, when the cutting edge detection unit is used, a non-contact type setup process for positioning the cutting blade at a predetermined height position can be performed.

  In order to perform the non-contact type setup process, the reference amount of light received by the photoelectric conversion unit when the cutting blade is positioned at a predetermined height is registered in the cutting device in advance. In the non-contact type setup process, the cutting blade is lowered toward the cutting blade entry groove. The predetermined height position at which the cutting blade is to be positioned by the setup process is the height position of the cutting blade when the amount of light received by the photoelectric conversion unit reaches the reference amount of light received.

JP 2001-298001 A

  When the operating time of the cutting device increases, dirt or the like may adhere to the light emitting part or light receiving part of the blade edge detection unit. Then, the light is blocked by the dirt, and the intensity of light emitted from the light emitting unit may be reduced, or the amount of light reaching the light receiving unit may be reduced. If the setup process is performed with the light emitting unit and the light receiving unit being dirty, the amount of light received by the photoelectric conversion unit before the cutting blade is positioned at a predetermined height matches the reference amount of light received Therefore, there arises a problem that the cutting blade cannot be positioned at a predetermined height position.

  Therefore, a function of monitoring the amount of received light received by the photoelectric conversion unit in a state where the cutting blade has not entered the cutting blade entry groove and issuing an alarm when the amount of received light falls below a predetermined threshold value is provided. A cutting device was developed. The cutting device urges the operator of the cutting device to clean the light emitting unit and the light receiving unit by issuing the alarm.

  However, the meaning of the alarm may not be correctly understood, and an operator or the like may increase the intensity of light emitted from the light emitting unit by inappropriately operating the light source without cleaning the light emitting unit or the light receiving unit. The alarm stops when the amount of light received by the photoelectric conversion unit increases and exceeds the predetermined threshold. However, in this state, it is difficult to properly detect the cutting edge by the cutting edge detection unit. Depending on the state of dirt adhering to the light emitting part and the light receiving part, there is a possibility that the blade edge can be detected. However, even in that case, it is not objectively confirmed whether or not the edge detection performed is appropriate.

  The present invention has been made in view of such problems, and an object of the present invention is to provide a cutting apparatus capable of determining whether or not a subsequent setup process is possible when dirt is attached to the blade edge detection unit. Is to provide.

  According to one aspect of the present invention, a chuck table for holding a workpiece, a cutting unit equipped with a cutting blade for cutting the workpiece held on the chuck table, and the cutting unit with respect to the chuck table. A cutting feed unit that moves in the cutting feed direction, a position recognition unit that recognizes the position of the cutting unit in the cutting feed direction, a light-emitting part and a light-receiving part, and the cutting feed direction at the lower end of the cutting edge of the cutting blade A cutting device comprising a blade edge detection unit for detecting a position in the position, a notification unit for issuing a warning, and a control unit for controlling each component, wherein the blade edge detection unit is disposed between the light emitting unit and the light receiving unit. The light is emitted from the light emitting part in a state where the cutting blade has entered, and the light is received without being blocked by the cutting blade. A blade edge detecting function for receiving the light reaching the section and detecting the position of the lower edge of the cutting edge of the cutting blade in the cutting direction from the amount of received light, and the control unit includes the light emitting section and the light receiving section. A light receiving amount determination unit that determines whether or not the amount of light received from the light emitting unit that has been emitted from the light emitting unit and received by the light receiving unit reaches a threshold value in a state where the cutting blade has not entered between The position of the cutting blade that enters between the light emitting unit and the light receiving unit in the cutting feed direction, and the amount of light received from the light emitting unit that reaches the light receiving unit without being blocked by the cutting blade. The amount of received light does not reach the threshold value in a state in which the cutting blade is not inserted between the light emitting unit and the light receiving unit, and the relationship registering unit in which the reference relationship is registered And the received light amount determination unit A lade enters between the light emitting part and the light receiving part, and the position of the cutting blade in the cutting feed direction and the light radiated from the light emitting part and reaching the light receiving part without being blocked by the cutting blade. The relationship between the received light amount is detected, the detected relationship is compared with the reference relationship registered in the relationship registration unit, and whether or not the blade edge detection unit can exhibit the blade edge detection function. A blade edge detection availability determination unit that determines whether or not the blade edge detection unit determines that the blade edge detection unit cannot perform the blade edge detection function. The cutting device characterized by emitting is provided.

  In one aspect of the present invention, the blade edge detection unit receives light that has reached the light receiving unit, and outputs an electrical signal corresponding to the amount of light received, and the light emitting unit emits the photoelectric conversion unit. A dimmer that adjusts the intensity of light, and the control unit, when the blade edge detection availability determination unit determines that the blade edge detection unit can perform the blade edge detection function, Increasing the intensity of light emitted from the light source, radiating from the light emitting unit and reaching the light receiving unit without receiving the cutting blade between the light emitting unit and the light receiving unit, and receiving light by the photoelectric conversion unit The amount of received light may be adjusted to be equal to or greater than the threshold value.

  In the cutting device according to one aspect of the present invention, the light emitted from the light emitting unit and received by the light receiving unit in a state where the cutting blade does not enter between the light emitting unit and the light receiving unit. The received light amount determination unit for determining whether or not the received light amount has reached the threshold value. When the dirt adhering to the blade edge detection unit is sufficiently small and the received light amount reaches the threshold value, the received light amount determination unit determines that the blade edge detection by the blade edge detection unit can be appropriately performed. In this case, the cutting device can appropriately perform the setup process using the blade edge detection unit.

  When the amount of dirt adhering to the blade edge detection unit exceeds a predetermined amount, the amount of received light does not reach the threshold value, and contamination of the blade edge detection unit is detected. However, even in this case, it is not immediately determined that the blade edge detection function by the blade edge detection unit cannot be exhibited. In the cutting apparatus, the blade edge detection availability determination unit determines whether the blade edge detection unit can detect the blade edge.

  The control unit of the cutting device according to one aspect of the present invention includes a relationship registration unit. In the relationship registration unit, when the dirt is not attached to the blade edge detection unit, the position of the lower edge of the cutting edge of the cutting blade in the cutting feed direction and the light emitting part that is emitted from the light emitting part and is not blocked by the cutting blade. The reference relationship between the amount of light received and received by the photoelectric conversion unit is registered.

  In a state where the light emitting part or the light receiving part of the blade edge detection unit is almost uniformly soiled throughout, the position of the lower edge of the cutting edge of the cutting blade in the cutting depth direction is received without being blocked by the cutting blade. The relationship between the amount of received light and the amount of received light is similar to the reference relationship. In this case, for example, by adjusting the light source connected to the light emitting unit so that the intensity of the light emitted from the light emitting unit is increased, the blade edge detecting unit becomes the same as when the blade edge detecting unit is not contaminated. The blade edge detection function can be demonstrated.

  On the other hand, if the light emitting portion and the light receiving portion are locally contaminated, the position of the lower end of the cutting edge of the cutting blade in the cutting depth direction and the light received without being blocked by the cutting blade The relationship between the received light amount and the reference relationship is not similar. Then, even if the intensity of light emitted from the light emitting unit is increased, the blade edge detection unit cannot exhibit the blade edge detection function.

  Therefore, the cutting edge detectability determination unit provided in the control unit of the cutting apparatus is based on the relationship between the position of the lower end of the cutting edge in the cutting depth direction and the amount of received light reaching the light receiving unit. Determine if the relationship is similar.

  The blade edge detection availability determination unit determines that the blade edge detection unit can perform the blade edge detection function when it is determined that the two are similar. In this case, the intensity of light emitted from the light emitting unit is adjusted so that the blade edge detection unit can exhibit the blade edge detection function. On the other hand, when the blade edge detection availability determination unit determines that the blade edge detection unit cannot perform the blade edge detection function, the control unit of the cutting device issues a warning to the notification unit, and the cutting device operator or the like detects the blade edge. Can inform about the necessity of cleaning the unit.

  In the cutting apparatus, when the cutting edge of the cutting blade can be detected even when dirt is attached to the cutting edge detection unit, the cutting edge can be detected after objectively confirming that the cutting edge can be detected. Therefore, a highly reliable setup process can be performed. Further, when the blade edge can be detected even if the blade edge detection unit is contaminated, the blade edge detection unit does not have to be cleaned immediately. For example, by carrying out cleaning in accordance with the timing of maintenance of the cutting device, the stop time of the cutting device can be reduced and the processing efficiency can be increased.

  Therefore, according to one aspect of the present invention, there is provided a cutting apparatus that can determine whether or not a subsequent setup process is possible when dirt adheres to the blade edge detection unit.

It is a perspective view which shows a cutting device typically. FIG. 2A is a perspective view schematically showing a blade edge detection unit, and FIG. 2B is a conceptual diagram schematically showing a cutting unit, a blade edge detection unit, and a control unit. FIG. 3A is a diagram schematically illustrating an example of display on the display unit, and FIG. 3B is a diagram schematically illustrating the relationship between the descent time of the cutting blade and the output voltage of the photoelectric conversion unit. It is. FIG. 4A is a side view schematically showing a light receiving portion and a cutting blade to which dirt is not attached, and FIG. 4B is a schematic view of the light receiving portion and the cutting blade to which dirt is attached. FIG.

  Embodiments according to one aspect of the present invention will be described with reference to the accompanying drawings. First, the cutting apparatus according to the present embodiment will be described with reference to FIG. FIG. 1 shows a cutting apparatus 2 for cutting a workpiece such as silicon, SiC (silicon carbide), other semiconductors, or a substantially disk-shaped substrate made of sapphire, glass, quartz, or the like. It is.

  The surface of the workpiece is partitioned by a plurality of division lines arranged in a lattice pattern, and a device such as an IC is formed in each partitioned region. Finally, each device chip is formed by dividing the work piece along the division line. For example, the workpiece is cut while being held on a tape stretched on an annular frame. When the workpiece is appropriately cut, the lower end of the cutting edge of a cutting blade described later reaches the tape.

  As shown in FIG. 1, the cutting device 2 includes a device base 4 that supports each component. At the upper center of the apparatus base 4, an X-axis movement table 6, an X-axis movement mechanism that moves the X-axis movement table 6 in the X-axis direction (machining feed direction), and a drainage channel 20 that covers the X-axis movement mechanism And are provided. The X-axis movement mechanism includes a pair of X-axis guide rails 12 parallel to the X-axis direction, and an X-axis movement table 6 is slidably attached to the X-axis guide rails 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 to 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 moving table 6 moves along the X-axis guide rail 12 in the X-axis direction.

  On the X-axis moving table 6, a chuck table 8 for sucking and holding a workpiece is provided. 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. The chuck table 8 is sent in the X-axis direction by the X-axis moving mechanism described above.

  The surface (upper surface) of the chuck table 8 serves as a holding surface 8a for sucking and holding the workpiece. The holding surface 8a is connected to a suction source (not shown) through a flow path (not shown) formed inside the chuck table 8. Around the holding surface 8a, a clamp 10 is provided for fixing an annular frame for holding the workpiece via a tape.

  A support structure 22 that supports the two cutting units 18 that cut the workpiece is disposed on the upper surface of the apparatus base 4 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 (index feed direction) and the Z-axis direction, respectively, is provided on the upper 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 the respective cutting units 18 are slidably attached to the Y-axis guide rail 24. A nut portion (not shown) is provided on the rear 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 to the nut portion. Are combined.

  A Y-axis pulse motor 28 a is connected to one end of the Y-axis ball screw 28. When the Y-axis ball motor 28 is rotated by the Y-axis pulse motor 28 a, 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. 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 the 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 along the Z-axis guide rail 30 in the Z-axis direction (cutting feed direction).

  A cutting unit 18 that processes the workpiece and an imaging unit (camera) 38 that can image the workpiece held on the chuck table 8 are fixed to the lower portions of the two Z-axis moving plates 32. Yes. 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 (index 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 includes an annular cutting blade 18a (see FIG. 2B) mounted on one end side of a spindle (not shown) constituting a rotation axis parallel to the Y-axis direction. A rotation driving source (not shown) such as a motor is connected to the other end side of the spindle, and the cutting blade 18a mounted on the spindle can be rotated. The cutting blade 18a has a disk-shaped base. A substantially circular mounting hole penetrating the base is provided at the center of the base. An annular cutting blade for cutting into the workpiece is fixed to the outer peripheral portion of the base.

  The cutting device 2 further includes a position recognition unit that recognizes the position of the cutting unit in the cutting feed direction. The cutting device 2 moves the cutting blade 18a in the cutting and feeding direction, positions it at a predetermined height position, and rotates the cutting blade 18a. Then, the workpiece can be cut by operating the X-axis moving mechanism to move the chuck table 8 in the machining feed direction and cutting the workpiece into the workpiece.

  At the time of cutting, the cutting blade 18a is positioned at a predetermined height using the position recognition unit so that the lower end 18b of the cutting edge of the cutting blade 18a reaches the tape attached to the back surface of the workpiece.

  The cutting device 2 further includes a control unit 46. The control unit 46 has a function of controlling each component of the cutting apparatus 2 such as the cutting unit 18, the chuck table 8, each moving mechanism, the imaging unit 38, and the blade edge detection unit 40 (described later). The function of the control unit 46 is realized, for example, as software for a device control computer.

  Moreover, as shown in FIG. 1, the cutting device 2 has the display part 42 which consists of a display panel with a touch panel, etc. The display unit 42 is electrically connected to the control unit 46. An operator or the like of the cutting apparatus 2 can input information such as machining conditions to the control unit 46 using the touch panel. The display unit 42 displays an interface image for inputting information and the like and operating the cutting device 2. Furthermore, the result of cutting, the result of determination in the control unit 46, and various warnings are displayed.

  Further, an alarm lamp 44 electrically connected to the control unit 46 is disposed on the upper part of the cutting device 2. The alarm lamp 44 includes, for example, a green lamp and a red lamp. When the cutting device 2 is in a normal operating state, the control unit 46 turns on the green lamp to notify an operator or the like that the cutting device 2 is normal. On the other hand, when any problem occurs in the cutting apparatus 2, the control unit turns on a red lamp to notify the operator or the like of that.

  The display unit 42 and the warning lamp 44 function as a notification unit that issues a warning to the operator of the cutting device 2.

  In the vicinity of the cutting unit 18 of the cutting apparatus 2, a blade edge detection unit 40 is disposed. When the blade edge detection unit 40 is used, a setup process for positioning the lower edge 18b (see FIG. 2B) of the blade edge of the cutting blade 18a at an appropriate height position (position in the cutting feed direction) can be performed. FIG. 2A is a perspective view schematically showing the blade edge detection unit 40, and FIG. 2B is a concept schematically showing the cutting unit 18, the blade edge detection unit 40, and the control unit 46. FIG.

  The main body 48 of the cutting edge detection unit 40 is provided with a cutting blade entry groove 48a that opens upward. When detecting the height position of the lower end 18b of the cutting edge of the cutting blade 18a, the cutting blade entry groove 48a is cut. The blade 18a is advanced.

  A light emitting part 50 is provided on one side wall of the cutting blade entry groove 48a, and a light receiving part 52 is provided on the other side wall of the cutting blade entry groove 48a at a position facing the light emitting part 50. A light source 50a is connected to the light emitting unit 50 via an optical fiber or the like, and light is emitted from the light emitting unit 50 when the light source 50a is operated. A dimmer 50b is connected to the light source 50a. The dimmer 50b has a function of adjusting the light emission amount of the light source 50a.

  A photoelectric conversion unit 52a is connected to the light receiving unit 52 via an optical fiber or the like, and the light reaching the light receiving unit 52 is received by the photoelectric conversion unit 52a. An optical sensor is incorporated in the photoelectric conversion unit 52a, and an electrical signal (for example, voltage) corresponding to the amount of received light is output from the photoelectric conversion unit 52a. The photoelectric conversion unit 52 a is electrically connected to the control unit 46 and transmits the electric signal to the control unit 46.

  The light emitting unit 50 and the light receiving unit 52 are provided at substantially the same height. The height position is a height position near the lower end 18b of the cutting edge of the cutting blade 18a when the cutting blade 18a is positioned at a predetermined height position (position in the cutting feed direction). The blade edge detection unit 40 is provided with an openable / closable cover 48b that protects the light emitting section 50 and the light receiving section 52 when the blade edge detection unit 40 is not used. When using the blade edge detection unit 40, the cover 48b is opened in advance to expose the main body 48 of the cutting blade 18a.

  The main body 48 is further provided with a plurality of fluid ejection nozzles facing the light emitting unit 50 or the light receiving unit 52. When a fluid such as air or water is ejected from the fluid ejection nozzle, dirt attached to the light emitting part 50 and the light receiving part 52 is removed, or adhesion of the dirt is suppressed. However, even if the fluid ejection nozzle is operated, dirt may remain on the light emitting unit 50 and the light receiving unit 52.

  When the cutting edge 18a of the cutting blade 18a is detected by the cutting edge detection unit 40, the light source 52a is activated to emit light from the light emitting portion 50 of the cutting blade entry groove 48a, and the light receiving portion 52 receives the light. In the photoelectric conversion unit 52a connected to the light receiving unit 52, the light received by the light receiving unit 52 is received by, for example, an optical sensor. The photoelectric conversion unit 52 a converts the light into an electrical signal (for example, voltage) corresponding to the amount of received light, and sends the electrical signal to the control unit 46.

  When the cutting blade 18a is lowered toward the cutting blade entry groove 48a, the light emitted from the light emitting unit 50 is gradually blocked by the cutting blade 18a, and the light received after reaching the light receiving unit 52 is received. The amount gradually decreases.

  Therefore, by analyzing the electrical signal output from the photoelectric conversion unit 52a by the control unit 46, the height position (position in the cutting feed direction) of the lower end 18b of the cutting edge of the cutting blade 18a can be detected. When the amount of received light reaching the light receiving unit 52 becomes the reference amount of received light, the height position of the lower end 18b of the blade edge detected by the control unit 46 becomes a predetermined height position.

  However, if dirt adheres to the light emitting unit 50 or the light receiving unit 52 of the blade edge detection unit 40, the dirt is blocked by the dirt, and the intensity of light emitted from the light emitting unit 50 is reduced, or the light receiving unit 52 In some cases, the amount of light that arrives and is received decreases. In these cases, the amount of received light reaches the reference amount of received light before the cutting blade 18a is positioned at a predetermined height position (position in the cutting feed direction). Therefore, there arises a problem that the cutting blade 18a cannot be positioned at a predetermined height position.

  Therefore, in a state where the cutting blade 18a has not entered the cutting blade entry groove 48a, the amount of light received and received by the light receiving unit 52 is monitored, and a notification is given when the amount of received light is below a predetermined threshold. It is possible to issue an alarm by the unit. By issuing the alarm, it is possible to prompt the operator of the cutting device 2 to clean and inspect the light emitting unit 50 and the light receiving unit 52. However, it is conceivable that an operator or the like improperly operates the light emitting unit 50 to adjust the intensity of light emitted from the light emitting unit 50 without understanding the meaning of the alarm correctly.

  For example, when the light emitting unit 50 and the light receiving unit 52 are substantially uniformly soiled throughout, the lower end 18b of the cutting edge of the cutting blade 18 is appropriately increased again by appropriately increasing the intensity of light emitted from the light emitting unit 50. In some cases, the height position of can be detected. However, even if the intensity of light is increased unplanned, the blade edge detection unit 40 is not always in a state where appropriate blade edge detection can be performed.

  Further, depending on the state of dirt adhering to the light emitting unit 50 and the light receiving unit 52, the height of the lower end 18b of the blade edge and the light receiving unit 52 can be reached simply by increasing the intensity of light emitted from the light emitting unit 50. The relationship between the amount of received light and the amount of received light may not be the normal relationship. In this case, even if the intensity of the light emitted from the light emitting unit 50 is adjusted, the blade edge detection unit 40 cannot detect the blade edge.

  Therefore, in the cutting device 2 according to the present embodiment, it is determined whether or not the blade edge can be detected when the light emitting unit 50 and the light receiving unit 52 of the blade edge detection unit 40 are dirty. When it is determined that the blade edge can be detected, the amount of light emitted from the light emitting unit 50 is adjusted so that the blade edge can be detected appropriately. In addition, if it is difficult to detect the appropriate cutting edge even after adjusting the light emission amount, the operator is warned to that effect and the cleaning or inspection of the cutting edge detection unit 40 is strongly urged.

  Hereinafter, the control unit 46 that realizes the determination of whether or not the blade edge can be detected by the blade edge detection unit 40 will be described. The control unit 46 includes a received light amount determination unit 54 electrically connected to the blade edge detection unit 40, a blade edge detection availability determination unit 56 connected to the received light amount determination unit 54, and the blade edge detection availability determination unit 56. A blade edge detection unit 58 connected to the.

  The received light amount determination unit 54 receives, for example, an electrical signal having a voltage corresponding to the received light amount of the light received by the photoelectric conversion unit 52a from the photoelectric conversion unit 52a. The received light amount determination unit 54, based on the electrical signal output from the photoelectric conversion unit 52a when the light emitted from the light emitting unit 50 reaches the light receiving unit 52 without being blocked by the cutting blade 18a. It is determined whether the amount of received light has reached a predetermined threshold. Details of the determination will be described later.

  The control unit 46 includes a threshold value registration unit 54 a connected to the received light amount determination unit 54. In the threshold value registration unit 54a, it is determined that the dirt attached to the light emitting unit 50 and the light receiving unit 52 of the blade edge detection unit 40 is sufficiently small and the blade edge detection unit 40 can detect the edge without being affected by the dirt. A threshold value relating to the amount of light that can be received is registered in advance. When the determination by the received light amount determination unit 54 is performed, the threshold value is read from the threshold value registration unit 54a.

  The received light amount determination unit 54 determines that the edge detection by the blade edge detection unit 40 can be performed as it is if the amount of light received by the light receiving unit 52 is equal to or greater than a predetermined threshold. On the other hand, when the light emitting unit 50 or the light receiving unit 52 has a relatively large amount of dirt or the like and the amount of received light is equal to or less than the threshold value, the received light amount determination unit 54 detects the blade edge by the blade edge detection unit 40. It is determined that determination by the blade edge detection availability determination unit 56 is necessary. In this case, the received light amount determination unit 54 sends the determination result to the blade edge detectability determination unit 56.

  When the amount of received light received by the light receiving unit 52 does not reach the threshold, the received light amount determination unit 54 notifies the fact with the information about the amount of received light received by the light receiving unit 52 (for example, the display unit 42). To the operator of the cutting device 2. FIG. 3A shows an example of display by the display unit 42.

  FIG. 3A is an example of a display showing the amount of light received by the photoelectric conversion unit 52a of the blade edge detection unit 40 in each of the two cutting units 18 (Z1, Z2) of the cutting device 2. In the display unit 42, the amount of received light that reaches the light receiving unit 52 and is received by the photoelectric conversion unit 52a is 100% of the amount of light received when the light emitting unit 50 and the light receiving unit 52 are not contaminated. The ratio is displayed.

  In FIG. 3 (A), there is little dirt adhering to the light emission part 50 or light-receiving part 52 of the blade edge | tip detection unit 40 which Z1 has, and dirt adhering to the light emission part 50 or light-receiving part 52 of the blade edge | tip detection unit 40 which Z2 has. The example of the display of the display part 42 when there are comparatively many is shown. In the example shown in FIG. 3A, a warning 42b indicating that the amount of received light is insufficient in Z2 is displayed on the display unit 42 because the amount of received light in Z2 is smaller than the threshold 54b read from the threshold value registration unit 54a. Is displayed.

  Even if dirt is attached to the light emitting unit 50 or the light receiving unit 52, the blade edge detection unit 40 may be able to detect the edge depending on the state of the dirt. Determine whether it is possible. Hereinafter, determination of whether or not the blade edge can be detected by the blade edge detection availability determination unit 56 will be described.

  First, when the light source 50a is activated and light is emitted from the light emitting unit 50, the cutting blade 18a is cut down at a constant speed along the feed direction, and the cutting blade 18a enters the cutting blade entry groove 48a. . In the blade edge detectability determination unit 56, the photoelectric conversion unit 52 a outputs the light depending on the elapsed time (down time) from the start of lowering in the cutting feed direction of the cutting blade 18 a and the amount of light received by the light receiving unit 52. The relationship with the voltage (output voltage) is obtained. An example of this relationship is shown in FIG.

  FIG. 3B shows a relationship 64a between the fall time and the output voltage when dirt is not attached to the light emitting unit 50 or the light receiving unit 52, and dirt is attached to the light emitting unit 50 or the light receiving unit 52. The relations 64b and 64c between the fall time and the output voltage in the case where the output is applied are shown. In FIG. 3B, the vertical axis indicates the voltage (output voltage) output from the photoelectric conversion unit 52a, and the horizontal axis indicates the elapsed time (fall time) from the start of the lowering of the cutting blade. .

  In the example shown in FIG. 3B, the output voltage in a state where it is not blocked by the cutting blade 18a or dirt is 5V. In a state where dirt is not attached to the light emitting unit 50 or the light receiving unit 52, an output voltage 66 serving as a reference when the lower end 18b of the cutting edge of the cutting blade 18a is positioned at a predetermined height position (position in the cutting feed direction). Is 3V.

The time when a portion of light emitted from the light emitting unit 50 starts blocked by the lower end 18b of the cutting edge of the cutting blade 18a and t _0, all light is blocked in the cutting blades 18a reach the light receiving portion 52 Let t ₁ be the time to disappear.

  4A and 4B schematically show the positional relationship between the light receiving portion 52 and the lower end 18b of the cutting edge of the cutting blade 18a when the output voltage becomes the reference output voltage 66. FIG. A side view is shown. FIG. 4A shows the height position of the lower end 18b of the blade edge when the light emitting unit 50 or the light receiving unit 52 is not contaminated. FIG. 4B shows the height position of the lower end 18 b of the blade edge when the dirt 68 is partially attached to the light receiving portion 52.

The relationship 64b in FIG. 3B shows the relationship between the output voltage and the fall time when the dirt 68 is partially attached to the light receiving portion 52 as shown in FIG. 4B. Yes. Since the soil is 68 blocks the light, the output voltage at time t ₀ does not become 5V, for example, a 4V. In this case, before the lower end 18b of the cutting edge of the cutting blade 18a is positioned at a predetermined height position, the output voltage becomes 3V of the reference output voltage 66.

A two-dot chain line shown in FIG. 4B indicates the position of the cutting edge of the cutting blade 18a when the output voltage is 3 V when the dirt 68 is not attached. When the dirt 68 adheres to the light receiving part 52, the output voltage becomes 3V before the lower end 18b of the blade edge reaches the position. In this case, for example, to implement an adjustment to increase the intensity of light emitted from the light emitting unit 50 connected dimmer 50b to the light source 50a of the light emitting unit 50, the output voltage of the time t ₀ to 5V However, proper blade edge detection by the blade edge detection unit 40 cannot be expected.

On the other hand, the relationship 64c shown in FIG. 3B is a relationship between the output voltage when the dirt is substantially uniformly applied to the entire surface of the light emitting unit 50 or the light receiving unit 52 and the fall time. is there. In this case, for example, becomes the output voltage at t ₀ as with the relationship 64c relationship 64b time 4V, a shape in which the relationship 64c is consistent with the relation 64a stretching in the vertical axis direction. That is, it can be said that the relationship 64c is similar to the relationship 64a.

Therefore, the output voltage of the time t ₀ is to adjust the output of the light source 50a by the dimmer 50b so that 5V, and the output voltage, and the fall time, the relationship the relationship 64a isomorphic. Then, the cutting blade 18a can be positioned so that the lower end 18b of the cutting edge is at a predetermined height position.

  Therefore, in the blade edge detection availability determination unit 56, the received light amount when the blade edge is not detected from the received light amount determination unit 54 does not reach the threshold value, and the blade edge detection availability determination unit 56 needs to determine whether or not the blade edge can be detected. When the determination is notified, it is determined whether or not the blade edge can be detected. A relationship registration unit 56 a is connected to the blade edge detection availability determination unit 56. The relationship registration unit 56a registers a reference relationship (for example, 64a) between the output voltage when the blade edge can be normally detected and the fall time, and the blade edge detection availability determination unit 56 makes a determination. When performing the above, the reference relationship is read out.

  Then, the relationship between the output voltage obtained by lowering the cutting blade 18a and the fall time is compared with the relationship registered in the relationship registration unit 56a, and whether or not they are similar. Judging. The blade edge detection availability determination unit 56 determines that the blade edge detection by the blade edge detection unit 40 is possible when it is determined to be similar.

  When the blade edge detection availability determination unit 56 determines that the blade edge detection unit 40 can detect the blade edge, the determination result is sent to the blade edge detection unit 58 and the dimmer 50b. Then, the intensity of light emitted from the light emitting unit 50 is adjusted by adjusting the light source 50a by the dimmer 50b, and the amount of light received by the light receiving unit 52 is registered in the threshold value registering unit 54a. Exceeding the threshold value.

  On the other hand, the relationship between the output voltage obtained by lowering the cutting blade 18a and the fall time is compared with the relationship registered in the relationship registration unit 56a. When it is determined that there is, the blade edge detection unit 40 determines that the blade edge detection function cannot be exhibited. At this time, the blade edge detectability determination unit 56 sends the determination result to the notification unit 62. Then, the notification unit 62 notifies the operator of the cutting apparatus 2 of the determination result and strongly urges cleaning and inspection of the blade edge detection unit 40.

  When the blade edge detection unit 58 receives the determination that the blade edge can be detected from the blade edge detection possibility determination unit 56, the light source 50 a is adjusted by the dimmer 50 b, and then the cutting blade 18 a is inserted again into the cutting blade entry groove 48 a. The cutting blade 18a is entered from above. Then, the height position of the cutting blade 18a when the lower end 18b of the cutting edge of the cutting blade 18a is positioned at a predetermined height can be determined.

  The blade edge detection unit 58 is connected to, for example, a correction unit 60 connected to the Z-axis pulse motor 36. Based on information on the height position of the cutting blade 18a when the lower end 18b of the cutting edge of the cutting blade 18a is positioned at a predetermined height, the correction unit 60 controls the Z-axis pulse motor 36 to control the cutting blade. 18a is positioned at the height position.

  In the cutting device 2 according to this embodiment, the cutting edge 18a can be set up by the cutting edge detection unit 40 in a non-contact manner. In the cutting apparatus 2 according to the present embodiment, when dirt is attached to the blade edge detection unit 40, it is determined whether or not a subsequent setup process is possible, and when the setup process can be performed, the light emitting unit emits the light. The intensity of light is adjusted.

  Therefore, even when dirt adheres to the blade edge detection unit 40, the cutting device 2 can exhibit the edge detection function of the edge detection unit 40 depending on the state of the dirt. In this case, even if the blade edge detection unit 40 becomes dirty, it is not necessary to clean immediately, so that cleaning and inspection can be performed in accordance with the maintenance of the cutting device 2 and the like. Since it is not necessary to stop the cutting device 2 only for cleaning or the like, the processing efficiency of the cutting device 2 can be increased.

  In the above-described embodiment, the case where the cutting device 2 has two cutting units and the setup process is performed by the blade edge detection unit 40 provided in each cutting unit 18 has been described. It is not limited to this. Two cutting units may be used in common and one cutting edge detection unit 40 may be used. Moreover, the number of the cutting units 18 provided in the cutting device 2 may be one.

  In the above-described embodiment, the description has been given of the case where the edge detection unit 40 of the cutting apparatus 2 is contaminated with the determination of whether the edge detection is possible and the intensity of light emitted from the light emitting unit 50 is adjusted. One embodiment of the present invention is not limited to this. In the cutting device 2 according to one aspect of the present invention, the cutting blade by the blade edge detection unit 40 even when the amount of light received by the photoelectric conversion unit 52a is different from normal due to a factor different from dirt. In some cases, it may be possible to perform edge detection.

  Here, the other factors include, for example, damage occurring on the surface exposed to the cutting blade entry groove 48a of the light emitting unit 50 and the light receiving unit 52 of the blade edge detection unit 40, and the light emitting unit 50 and the light receiving unit 52 connected to the light emitting unit 50. This is a change in the bending state of the optical fiber. In these cases, similarly to the above embodiment, the received light amount determination unit 54 can determine whether or not the received light amount has reached the threshold value. Further, it is possible to determine whether or not the blade edge detection unit 40 can detect the blade edge by operating the blade edge detection possibility determination unit 56, and when it is determined that the light edge 50a is determined, the light source 50a is adjusted by the dimmer 50b.

  However, in this case, even if the cutting edge detection unit 40 is inspected and cleaned, the amount of received light determined by the received light amount determination unit 54 does not reach the threshold, or the height position of the cutting blade 18a and the photoelectric conversion unit 52a In some cases, the relationship between the output voltage and the reference voltage is not similar to the reference relationship. That is, there are cases where the blade edge detection unit 40 does not return to the initial state even after inspection and cleaning.

  In the cutting device 2 according to one aspect of the present invention, the blade edge detection unit 40 can be adjusted so that the blade edge detection function of the blade edge detection unit 40 can be exhibited even in such a case. First, the light emitted from the light source 50a is adjusted by the dimmer 50b, and the received light amount of the light received by the photoelectric conversion unit 52a is set to a threshold value or more. Next, in this state, the cutting blade 18a enters the cutting blade entry groove 48a, obtains the relationship between the descending time of the cutting blade 18a and the output voltage, and uses this relationship as a new reference relationship as a relationship registration unit. Register in 56a.

  Furthermore, a setup process for bringing the chuck table 8 and the cutting blade 18a into contact is performed, the lower end of the cutting edge of the cutting blade 18a is positioned at a predetermined height position, and the output voltage of the photoelectric conversion unit 52a at that time is Set to the new reference output voltage. Then, the blade edge detection unit 40 can perform the non-contact type setup process again.

  Such adjustment of the blade edge detection unit 40 may be performed when dirt is attached to the light emitting unit 50 or the light receiving unit 52. That is, the blade edge detectability determination unit 56 compares the relationship between the output voltage of the photoelectric conversion unit 52a and the descent time of the cutting blade 18a with the relationship registered in the relationship registration unit 56a. When it is determined that the two are dissimilar, the blade edge detection unit 40 may be adjusted.

  In addition, the structure, method, and the like according to the above-described embodiment can be appropriately modified and implemented without departing from the scope of the object of the present invention.

2 Cutting device 4 Device base 6 X-axis moving table 8 Chuck table 8a Holding surface 10 Clamp 12 X-axis guide rail 14 X-axis ball screw 16 X-axis pulse motor 18 Cutting unit 18a Cutting blade 18b Lower end of cutting edge 20 Drainage path 22 Support Structure 24 Y-axis guide rail 26 Y-axis moving plate 28 Y-axis ball screw 28a Y-axis pulse motor 30 Z-axis guide rail 32 Z-axis moving plate 34 Z-axis ball screw 36 Z-axis pulse motor 38 Imaging unit (camera)
40 Cutting edge detection unit 42 Display monitor 42a Light receiving amount gauge 42b Warning 44 Alarm lamp 46 Control unit 48 Main body 48a Cutting blade entry groove 48b Cover 50 Light emitting unit 50a Light source 50b Dimmer 52 Light receiving unit 52a Photoelectric conversion unit 54 Light receiving amount judgment unit 54a Threshold registration unit 54b Threshold 56 Cutting edge detection availability determination unit 56a Relation registration unit 58 Cutting edge detection unit 60 Correction unit 62 Notification unit 64a, 64b, 64c Relationship between the descent time of the cutting blade and the output voltage 66 Reference voltage 68 Dirt

Claims (2)

A chuck table for holding a workpiece, a cutting unit equipped with a cutting blade for cutting the workpiece held on the chuck table, and a notch for moving the cutting unit in the cutting feed direction with respect to the chuck table A feed unit, a position recognition unit for recognizing the position of the cutting unit in the cutting feed direction, and a blade edge detection unit that has a light emitting part and a light receiving part and detects the position of the lower edge of the cutting edge of the cutting blade in the cutting feed direction And a cutting device comprising a notification unit that issues a warning, and a control unit that controls each component,
The blade edge detection unit emits light from the light emitting unit in a state where a cutting blade enters between the light emitting unit and the light receiving unit, and reaches the light receiving unit without being blocked by the cutting blade of the light. Receiving a light, having a blade edge detection function for detecting the position in the cutting direction of the lower edge of the cutting edge of the cutting blade from the amount of light received;
The control unit is
Whether the amount of received light of the light emitted from the light emitting part and reaching the light receiving part and received in a state where the cutting blade has not entered between the light emitting part and the light receiving part has reached a threshold value. A received light amount determination unit for determining;
A position in the cutting feed direction of the cutting blade that enters between the light emitting unit and the light receiving unit, and a light receiving amount of light that is emitted from the light emitting unit and reaches the light receiving unit without being blocked by the cutting blade, A relationship registration unit for registering relationships that serve as criteria for
When the received light amount determination unit determines that the received light amount of received light has not reached the threshold value when the cutting blade has not entered between the light emitting unit and the light receiving unit, the cutting blade Is inserted between the light-emitting part and the light-receiving part, and the position of the cutting blade in the cutting feed direction and the reception of light emitted from the light-emitting part and reaching the light-receiving part without being blocked by the cutting blade The relationship between the amount and the detected relationship is compared with the reference relationship registered in the relationship registration unit, and whether or not the blade edge detection unit can exhibit the blade edge detection function is determined. A blade edge detection availability determination unit for determining,
A cutting device that issues a warning prompting the inspection of the cutting edge detection unit from the notification unit when the cutting edge detection possibility determination unit determines that the cutting edge detection unit cannot perform the cutting edge detection function. The blade edge detection unit is
A photoelectric conversion unit that receives the light reaching the light receiving unit and outputs an electrical signal corresponding to the amount of light received;
A dimmer that adjusts the intensity of light emitted by the light emitting unit, and
The control unit increases the intensity of light emitted from the light emitting unit by the dimmer when the blade edge detection availability determination unit determines that the blade edge detection unit can perform the blade edge detection function. So that the amount of light received from the light-emitting unit and received by the photoelectric conversion unit when the cutting blade does not enter between the light-receiving unit and the light-receiving unit is equal to or greater than the threshold value. The cutting device according to claim 1, wherein the cutting device is adjusted.