How to shape a cutting blade
The described method efficiently shapes cutting blades by using a cutting apparatus with multiple motors and threshold current detection to minimize repetitive movements and prevent damage, addressing inefficiencies in existing shaping methods.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- DISCO CORP
- Filing Date
- 2022-08-02
- Publication Date
- 2026-05-15
AI Technical Summary
The existing methods for shaping cutting blades in cutting apparatuses are inefficient, leading to prolonged processing times and potential damage due to variations in dressing board surfaces and increased force on the cutting blade, which can cause breakage and deteriorate processing quality.
A method involving a cutting apparatus with multiple motors for precise control of spindle movement and contact with a dressing board, using threshold current values to determine contact and shape the cutting blade efficiently, reducing the number of repetitive movements required.
This method reduces the time required for shaping the cutting blade by minimizing unnecessary movements and preventing damage, thereby improving throughput in cutting machines.
Smart Images
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Abstract
Description
Technical Field
[0001] The present invention relates to a method of shaping a cutting blade in a cutting apparatus including a holding table that holds a dressing board on an upper surface thereof, and a spindle that extends along a direction parallel to the upper surface of the holding table and has an annular cutting blade attached to a tip end portion thereof.
Background Art
[0002] Chips of devices such as ICs (Integrated Circuits) are essential components in various electronic devices such as mobile phones and personal computers. Such chips are manufactured, for example, by dividing a workpiece such as a package substrate having a large number of devices formed on its surface into regions each including an individual device.
[0003] As a method of dividing a workpiece, for example, cutting in a cutting apparatus can be mentioned. This cutting apparatus generally includes a holding table capable of holding a workpiece on an upper surface thereof, and a spindle that extends along a direction parallel to the upper surface of the holding table and has an annular cutting blade attached to a tip end portion thereof.
[0004] And in this cutting apparatus, the workpiece is cut by bringing the cutting blade into contact with the workpiece held on the upper surface of the holding table in a state where the cutting blade is rotated together with the spindle. Further, when such cutting of the workpiece is repeated, the cutting blade wears, and its outer peripheral end becomes rounded and tapered, so-called R shape.
[0005] Then, when cutting a workpiece using a cutting blade having an R-shaped outer peripheral end, the processing quality of the workpiece may deteriorate. For example, in this case, the processing track formed on the workpiece by cutting may meander.
[0006] Therefore, a method has been proposed to shape the outer edge of a cutting blade to be flattened using a dressing board held on the upper surface of a holding table (see, for example, Patent Document 1). In this method, first, the cutting blade is rotated together with the spindle, and the surface of the dressing board is brought into contact with the lower end of the cutting blade.
[0007] Then, while the cutting blade is rotating, the cutting blade is alternately moved back and forth multiple times along the direction in which the spindle extends, and the holding table and the cutting blade are brought slightly closer together along a direction perpendicular to the upper surface of the holding table. As a result, the outer edge of the cutting blade is shaved and flattened. [Prior art documents] [Patent Documents]
[0008] [Patent Document 1] Japanese Patent Publication No. 2010-588 [Overview of the project] [Problems that the invention aims to solve]
[0009] Dressing boards are manufactured, for example, by mixing abrasive particles with a resin binder and then firing the mixture. However, when dressing boards are manufactured in this way, the surface height can vary. For example, the difference in height between the highest and lowest points on the surface of this dressing board can be several hundred micrometers.
[0010] Furthermore, if the rotating cutting blade is moved along the direction in which the spindle extends, and the portion inside the outer edge of the blade, as well as the outer edge, is brought into contact with the surface of the dressing board, the force acting on the cutting blade will increase, potentially causing the cutting blade to break.
[0011] Therefore, the shaping of the cutting blade described above may begin with the lower end of the cutting blade positioned sufficiently higher than the surface of the dressing board so that the portion of the cutting blade inside the outer edge of the cutting blade does not come into contact with the surface of the dressing board.
[0012] In this case, even though the surface of the dressing board and the lower end of the cutting blade are not in contact, the cutting blade will repeatedly make multiple reciprocating movements along the direction in which the spindle extends, and the holding table and the cutting blade will come into slight proximity along the direction perpendicular to the upper surface of the holding table, alternating between the two.
[0013] This allows the outer edge of the cutting blade to be flattened without damaging it. However, this increases the time required to shape the cutting blade. As a result, the throughput of workpiece processing in the cutting machine may decrease.
[0014] In view of this, the object of the present invention is to provide a method for shaping a cutting blade that can suppress the prolongation of the time required for shaping the cutting blade. [Means for solving the problem]
[0015] According to one aspect of the present invention, a cutting apparatus comprising: a holding table that holds a dressing board on its upper surface; a spindle that extends along a first direction parallel to the upper surface of the holding table and has an annular cutting blade attached to its tip; a first motor for rotating the spindle with a straight line along the first direction as the axis of rotation; a second motor for moving the holding table or the spindle along the first direction or a second direction opposite to the first direction; and a third motor for moving the holding table or the spindle along a third direction perpendicular to the upper surface of the holding table or a fourth direction opposite to the third direction, wherein a method for shaping a cutting blade is provided, comprising a contact step of moving the holding table and the spindle relative to each other so that the surface of the dressing board and the lower end of the cutting blade come into contact, and the dressing board The contact step and the shaping step include, after it is determined that the surface of the cutting blade and the lower end of the cutting blade have come into contact, the shaping step of moving the holding table and the spindle relative to each other to shape the cutting blade, wherein each of the contact step and the shaping step includes, a first drive step of driving a second motor to drive the first motor to rotate the spindle at a constant rotational speed, while driving the tip of the spindle to pass over the dressing board at a constant speed, and a second drive step of driving the third motor to bring the tip of the spindle closer to the dressing board, wherein in the contact step, at least one first drive step and one second drive step are repeated alternately, and in the shaping step, the first drive step and one second drive step are repeated alternately more times than the number of times the first drive step is performed consecutively in the contact step. and implement And so, The contact process A method for shaping a cutting blade is provided, which determines that the surface of the dressing board and the lower end of the cutting blade have come into contact when the maximum value of the current supplied to the first motor, which changes over time, exceeds a first threshold value during the first driving process.
[0016] According to another aspect of the present invention, a cutting apparatus comprising: a holding table that holds a dressing board on its upper surface; a spindle that extends along a first direction parallel to the upper surface of the holding table and has an annular cutting blade mounted at its tip; a first motor for rotating the spindle with a straight line along the first direction as the axis of rotation; a second motor for moving the holding table or the spindle along the first direction or a second direction opposite to the first direction; and a third motor for moving the holding table or the spindle along a third direction perpendicular to the upper surface of the holding table or a fourth direction opposite to the third direction, wherein a method for shaping a cutting blade is provided, comprising a contact step of moving the holding table and the spindle relative to each other so that the surface of the dressing board and the lower end of the cutting blade come into contact, and the dressing board The contact step and the shaping step include, after it is determined that the surface of the cutting blade and the lower end of the cutting blade have come into contact, the shaping step of moving the holding table and the spindle relative to each other to shape the cutting blade, wherein each of the contact step and the shaping step includes, a first drive step of driving a second motor to drive the first motor to rotate the spindle at a constant rotational speed, while driving the tip of the spindle to pass over the dressing board at a constant speed, and a second drive step of driving the third motor to bring the tip of the spindle closer to the dressing board, wherein in the contact step, at least one first drive step and one second drive step are repeated alternately, and in the shaping step, the first drive step and one second drive step are repeated alternately more times than the number of times the first drive step is performed consecutively in the contact step. and implement And so, The contact process A method for shaping a cutting blade is provided, which determines that the surface of the dressing board and the lower end of the cutting blade have come into contact when the maximum value of the current supplied to the second motor, which changes over time, exceeds a first threshold value during the first driving process.
[0017] Furthermore, in the present invention, in the shaping process, after the first driving process is continuously repeated until it is determined that the surface of the dressing board and the lower end of the cutting blade no longer contact each other, the second driving process is carried out. The shaping process When the maximum value of the current supplied to the first motor that changes over time in the first driving process is less than the second threshold value, it is determined that the surface of the dressing board and the lower end of the cutting blade no longer contact each other. vinegar to thing is preferable.
[0018] Alternatively, in the present invention, in the shaping process, after the first driving process is continuously repeated until it is determined that the surface of the dressing board and the lower end of the cutting blade no longer contact each other, the second driving process is carried out. The shaping process When the maximum value of the current supplied to the second motor that changes over time in the first driving process is less than the second threshold value, it is determined that the surface of the dressing board and the lower end of the cutting blade no longer contact each other. vinegar to thing is preferable.
Advantages of the Invention
[0019] In the present invention, when the maximum value of the current supplied to a predetermined motor that changes over time in the first driving process exceeds the first threshold value, it is determined that the surface of the dressing board and the lower end of the cutting blade are in contact.
[0020] In this case, the number of times the first driving process is repeated in the contact process can be made less than the number of times the first driving process is repeated in the shaping process. As a result, in the present invention, it is possible to suppress an increase in the time required for shaping the cutting blade.
Brief Description of the Drawings
[0021] [Figure 1]FIG. 1(A) is a perspective view schematically showing an example of a frame unit including a dressing board, and FIG. 1(B) is a cross-sectional view schematically showing the frame unit shown in FIG. 1(A). [Figure 2] FIG. 2 is a perspective view schematically showing an example of a cutting device. [Figure 3] FIG. 3(A) is a perspective view schematically showing the cutting blade shown in FIG. 2, and FIG. 3(B) is a front view schematically showing the cutting blade shown in FIG. 2. [Figure 4] FIG. 4 is a functional block diagram schematically showing an example of a control unit incorporated in the cutting device shown in FIG. 2. [Figure 5] FIG. 5 is a flowchart schematically showing an example of a method for shaping a cutting blade in the cutting device shown in FIG. 2. [Figure 6] Each of FIGS. 6(A) and 6(B) is a partial cross-sectional side view schematically showing the state of the first driving step. [Figure 7] Each of FIGS. 7(A) and 7(B) is a partial cross-sectional side view schematically showing the state of the second driving step. [Figure 8] FIG. 8 is a flowchart schematically showing an example of the contact step S1 shown in FIG. 5. [Figure 9] FIG. 9 is a flowchart schematically showing an example of the shaping step S2 shown in FIG. 5. [Figure 10] FIG. 10 is a flowchart schematically showing another example of the contact step S1 shown in FIG. 5. [Figure 11] FIG. 11 is a flowchart schematically showing another example of the shaping step S2 shown in FIG. 5. [Figure 12] FIG. 12 is a flowchart schematically showing yet another example of the shaping step S2 shown in FIG. 5.
MODE FOR CARRYING OUT THE INVENTION
[0022] Embodiments of the present invention will be described with reference to the attached drawings. Figure 1(A) is a schematic perspective view showing an example of a frame unit including a dressing board used for shaping a cutting blade, and Figure 1(B) is a schematic cross-sectional view showing the frame unit shown in Figure 1(A).
[0023] The frame unit 11 shown in Figures 1(A) and 1(B) has a rectangular dressing board 13. This dressing board 13 is manufactured, for example, by kneading green carborundum (GC) abrasive grains made of silicon carbide (SiC) or white alundum (WA) abrasive grains made of aluminum oxide (Al2O3) with a resin binder and then firing it.
[0024] The surface 13a of the dressing board 13 manufactured in this manner has variations in height. In addition, the central region of a disc-shaped tape 15, whose diameter is larger than the diagonal of the dressing board 13, is attached to the back surface 13b of the dressing board 13. This tape 15 has, for example, a flexible film-like base layer and an adhesive layer (glue layer) provided on one side of the base layer (the side facing the dressing board 13).
[0025] The base layer consists of polyolefin (PO), polypropylene (PP), polyethylene terephthalate (PET), polyvinyl chloride (PVC), or polystyrene (PS), etc. The adhesive layer consists of UV-curable silicone rubber, acrylic material, or epoxy material, etc.
[0026] Furthermore, an annular frame 17 is attached to the outer periphery of the tape 15, with a circular opening having a diameter larger than the diagonal of the dressing board 13. This frame 17 is made of a metal material such as aluminum or stainless steel.
[0027] Figure 2 is a schematic perspective view showing an example of a cutting apparatus capable of shaping a cutting blade using a dressing board 13. Note that the +X axis direction (forward direction) and the +Y axis direction (left direction) shown in Figure 2 are mutually orthogonal directions on the horizontal plane, and the +Z axis direction (upward direction) is orthogonal to the +X axis direction and the +Y axis direction, respectively.
[0028] Furthermore, the -X-axis direction (backward direction) shown in Figure 2 is the opposite direction of the +X-axis direction, the -Y-axis direction (rightward direction) is the opposite direction of the +Y-axis direction, and the -Z-axis direction (downward direction) is the opposite direction of the +Z-axis direction. In the following, the +X-axis direction and the -X-axis direction will be collectively referred to as the X-axis direction, the +Y-axis direction and the -Y-axis direction will be collectively referred to as the Y-axis direction, and the +Z-axis direction and the -Z-axis direction will be collectively referred to as the Z-axis direction.
[0029] The cutting apparatus 2 shown in Figure 2 includes a base 4 that supports each component. A recess 4a extending along the X-axis is formed on the upper surface of the base 4. Inside the recess 4a, a flat table cover 6 and a bellows-shaped dustproof and dripproof cover 8 that expands and contracts as the table cover 6 moves are provided.
[0030] Furthermore, a holding table 10 is provided above the table cover 6. This holding table 10 has a disc-shaped frame 10a made of ceramics or the like. The frame 10a has a disc-shaped bottom wall and cylindrical side walls that rise from this bottom wall. A disc-shaped porous plate 10b made of porous ceramics, for example, is fixed to the recess defined by the bottom wall and side walls of the frame 10a.
[0031] The porous plate 10b has a diameter approximately equal to the inner diameter of the side wall of the frame 10a. Furthermore, the porous plate 10b communicates with a suction source (not shown), such as an ejector, provided inside the recess 4a, through a through hole or the like formed in the bottom wall of the frame 10a. The holding table 10 has an upper surface perpendicular to the Z-axis direction, and the dressing board 13 is held on this upper surface.
[0032] Specifically, when the frame unit 11, including the dressing board 13, is loaded into the cutting machine 2, the dressing board 13 is placed on the upper surface of the holding table 10 via the tape 15. Then, when the suction source communicating with the porous plate 10b is activated, a suction force acts on the dressing board 13 via the tape 15, holding the dressing board 13 on the upper surface of the holding table 10.
[0033] Furthermore, multiple clamps 12 are provided around the holding table 10. The multiple clamps 12 are provided at approximately equal angular intervals along the circumferential direction of the holding table 10. When the frame unit 11 is loaded into the cutting device 2, the multiple clamps 12 grip the frame 17 at a position lower than the upper surface of the holding table 10.
[0034] Furthermore, the holding table 10 and the multiple clamps 12 are connected to an X-axis movement mechanism (not shown) provided inside the recess 4a. This X-axis movement mechanism includes, for example, a ball screw and a motor connected to the ball screw.
[0035] When this X-axis movement mechanism is activated, the holding table 10 and the multiple clamps 12 move along the X-axis. Furthermore, as these move, the table cover 6 moves along the X-axis and the dustproof and waterproof cover 8 expands and contracts.
[0036] Furthermore, the holding table 10 and the multiple clamps 12 are connected to a rotational drive source (not shown) located inside the recess 4a. This rotational drive source includes, for example, a spindle and a motor connected to the spindle.
[0037] When this rotational drive source is activated, the holding table 10 and the multiple clamps 12 rotate with a rotation axis that passes through the center of the upper surface of the porous plate 10b and is aligned with the Z-axis direction.
[0038] A support structure 16 is provided in the area near the recess 4a on the upper surface of the base 4. This support structure 16 has an upright portion 16a extending from the upper surface of the base 4 along the +Z axis, and an arm portion 16b extending from the upper end of the upright portion 16a along the -Y axis so as to span the recess 4a. A Y-axis movement mechanism 18 is provided on the front side of the arm portion 16b.
[0039] This Y-axis movement mechanism 18 is fixed to the front of the arm portion 16b and has a pair of Y-axis guide rails 20 that extend along the Y-axis direction. A Y-axis movement plate 22 is connected to the front side of the pair of Y-axis guide rails 20 in a manner that allows it to slide along the pair of Y-axis guide rails 20.
[0040] Furthermore, a screw shaft 24 extending along the Y-axis direction is positioned between the pair of Y-axis guide rails 20. A motor (not shown) for rotating the screw shaft 24 is connected to one end of this screw shaft 24. A nut (not shown) for housing a number of balls that roll on the surface of the rotating screw shaft 24 is provided on the surface of the screw shaft 24, where a helical groove is formed, thus forming a ball screw.
[0041] In other words, as the screw shaft 24 rotates, numerous balls circulate within the nut, causing the nut to move along the Y-axis direction. This nut is fixed to the rear side of the Y-axis moving plate 22. Therefore, by rotating the screw shaft 24 with a motor connected to one end of the screw shaft 24, the Y-axis moving plate 22 moves along the Y-axis direction along with the nut.
[0042] A Z-axis movement mechanism 26 is provided on the front side of the Y-axis movement plate 22. This Z-axis movement mechanism 26 has a pair of Z-axis guide rails 28 that are fixed to the front of the Y-axis movement plate 22 and extend along the Z-axis direction. The Z-axis movement plate 30 is connected to the front side of the pair of Z-axis guide rails 28 in a manner that allows it to slide along the pair of Z-axis guide rails 28.
[0043] Furthermore, a screw shaft 32 extending along the Z-axis direction is positioned between a pair of Z-axis guide rails 28. A motor 34 for rotating the screw shaft 32 is connected to one end (upper end) of this screw shaft 32. A nut (not shown) is provided on the surface of the screw shaft 32, where a helical groove is formed, to accommodate a number of balls that roll on the surface of the rotating screw shaft 32, thus forming a ball screw.
[0044] In other words, as the screw shaft 32 rotates, numerous balls circulate within the nut, causing the nut to move along the Z-axis direction. This nut is fixed to the rear side of the Z-axis moving plate 30. Therefore, when the screw shaft 32 is rotated by the motor 34, the Z-axis moving plate 30 moves along the Z-axis direction along with the nut.
[0045] A cutting unit 36 is fixed to the lower part of the Z-axis moving plate 30. This cutting unit 36 has a cylindrical spindle housing 38 that extends along the Y-axis direction and a cutting blade 40 exposed from the spindle housing 38. Figure 3(A) is a schematic perspective view of the cutting blade 40, and Figure 3(B) is a schematic front view of the cutting blade 40.
[0046] The spindle housing 38 of the cutting unit 36 houses a cylindrical spindle 42 that extends along the Y-axis. This spindle 42 is supported by the spindle housing 38 in a rotatable manner. The tip of the spindle 42 protrudes outside the spindle housing 38, and a cutting blade 40 having an annular cutting edge 40a is mounted on this tip.
[0047] The cutting edge 40a is made of an electroformed grinding wheel in which abrasive grains, such as diamond or cubic boron nitride (cBN), are fixed with a binder such as nickel. The outer edge of the cutting blade 40 (the outer edge of the cutting edge 40a) has a rounded, tapered shape, a so-called R shape.
[0048] Furthermore, the base end of the spindle 42 is connected to a motor (first motor) built into the spindle housing 38. When this first motor is operated, the cutting blade 40 rotates together with the spindle 42, with a straight line along the Y-axis as the axis of rotation. The cutting blade 40 is mounted on the spindle 42 such that the straight line that forms the axis of rotation of the spindle 42 passes through the center of the cutting blade 40.
[0049] Furthermore, when the motor (second motor) connected to one end of the screw shaft 24 is operated, the cutting unit 36, including the spindle 42, moves along the Y-axis. Also, when the motor (third motor) 34 connected to one end of the screw shaft 32 is operated, the cutting unit 36, including the spindle 42, moves along the Z-axis.
[0050] As shown in Figure 2, a measuring unit 44 is provided in the +X axis direction relative to the cutting unit 36. This measuring unit 44 measures the height of the area irradiated by the laser beam, for example, by irradiating a laser beam onto the surface 13a of the dressing board 13 held on the upper surface of the holding table 10.
[0051] Furthermore, the cutting device 2 incorporates a control unit that controls the above-mentioned components. Figure 4 is a schematic functional block diagram showing an example of this control unit. The control unit 46 shown in Figure 4 has a processing unit 48 and a storage unit 50.
[0052] The processing unit 48 is composed of a processor, such as a CPU (Central Processing Unit). The storage unit 50 is composed of volatile memory, such as DRAM (Dynamic Random Access Memory) or SRAM (Static Random Access Memory), and non-volatile memory, such as an SSD (Solid State Drive) (NAND flash memory) or an HDD (Hard Disk Drive) (magnetic storage device).
[0053] The storage unit 50 stores various types of information (data, programs, etc.) used in the processing unit 48. For example, the storage unit 50 stores information used to determine whether or not the surface 13a of the dressing board 13 held on the upper surface of the holding table 10 is in contact with the lower end of the cutting blade 40 (the lower end of the cutting edge 40a) that rotates with the spindle 42.
[0054] Furthermore, when the two motors are in contact, the load torque applied to the first motor for rotating the spindle 42 and the load torque applied to the second motor for moving the spindle 42 along the Y-axis are greater than when they are not in contact.
[0055] In other words, when the two are in contact, the current supplied to the first motor to move the spindle 42 at a constant rotational speed and the current supplied to the second motor to move the spindle 42 at a constant moving speed are both larger compared to when they are not in contact.
[0056] Therefore, the information used for this determination may include, for example, a threshold value for the current supplied to the first motor for rotating the spindle 42, or a threshold value for the current supplied to the second motor for moving the spindle 42 along the Y-axis.
[0057] The processing unit 48 reads and executes various programs stored in the storage unit 50 to control the components of the cutting device 2. This processing unit 48 includes, for example, a drive unit 52 and a determination unit 54. The drive unit 52 controls the movement or rotation of the components of the cutting device 2.
[0058] For example, the drive unit 52 drives a motor for moving the holding table 10 along the X-axis, a motor for rotating the holding table 10, a first motor for rotating the spindle 42, a second motor for moving the spindle 42 along the Y-axis, and a third motor 34 for moving the spindle 42 along the Z-axis.
[0059] The determination unit 54 determines whether the surface 13a of the dressing board 13, which is held on the upper surface of the holding table 10, is in contact with the lower end of the cutting blade 40, which rotates together with the spindle 42.
[0060] For example, the determination unit 54 determines that the surface 13a of the dressing board 13 and the lower end of the cutting blade 40 have come into contact when the current supplied to the first motor to drive the spindle 42 to rotate at a constant rotational speed exceeds a threshold value stored in the storage unit 50.
[0061] Alternatively, the determination unit 54 determines that the surface 13a of the dressing board 13 and the lower end of the cutting blade 40 have come into contact when the current supplied to the second motor to drive the second motor to move the spindle 42 at a constant speed exceeds a threshold value stored in the storage unit 50.
[0062] Furthermore, in the cutting apparatus 2, the dressing board 13 is held on the upper surface of the holding table 10, and the lower end of the cutting blade 40 is positioned at a height assumed to be higher than the surface 13a of the dressing board 13, thereby enabling the cutting blade 40 to be shaped.
[0063] The height that is assumed to be higher than the surface 13a of the dressing board 13 is calculated, for example, by measuring the height of each of the five points included in the surface 13a of the dressing board 13 using the measuring unit 44, and then adding 100 μm to the average of the heights of the five points.
[0064] Figure 5 is a schematic flowchart illustrating an example of a method for shaping the cutting blade 40 in the cutting apparatus 2. In this method, the surface 13a of the dressing board 13 and the lower end of the cutting blade 40 are brought into contact (contact step S1), and then the cutting blade 40 is shaped (shaping step S2).
[0065] Furthermore, each of the contact process S1 and the shaping process S2 includes a first drive step of driving a first motor to rotate a spindle 42, on which a cutting blade 40 is attached to its tip, at a constant rotational speed, while driving a second motor to move the tip of the spindle 42 over the dressing board 13 at a constant speed, and a second drive step of driving a third motor to bring the tip of the spindle 42 closer to the dressing board 13.
[0066] Figures 6(A) and 6(B) are schematic cross-sectional side views illustrating the first drive process. Figures 7(A) and 7(B) are schematic cross-sectional side views illustrating the second drive process.
[0067] Specifically, in the first driving step shown in Figure 6(A), the drive unit 52 first drives the first motor to rotate the spindle 42, whose tip is positioned in the +Y axis direction relative to the dressing board 13 in a plan view, at a constant rotational speed. Then, while the spindle 42 is rotating, the drive unit 52 drives the second motor to move the tip of the spindle 42 over the dressing board 13 at a constant speed along the -Y axis.
[0068] Furthermore, in the first driving step shown in Figure 6(B), the drive unit 52 first drives the first motor to rotate the spindle 42, whose tip is positioned in the -Y-axis direction relative to the dressing board 13 in a plan view, at a constant rotational speed. Then, while the spindle 42 is rotating, the drive unit 52 drives the second motor to move the tip of the spindle 42 over the dressing board 13 at a constant speed along the +Y-axis direction.
[0069] Furthermore, in the second drive step shown in Figure 7(A), the drive unit 52 drives the third motor 34 to move the spindle 42, whose tip is positioned in the +Y-axis direction as viewed from the dressing board 13, slightly along the -Z-axis direction. Furthermore, in the second drive step shown in Figure 7(B), the drive unit 52 drives the third motor 34 to move the spindle 42, whose tip is positioned in the -Y-axis direction as viewed from the dressing board 13, slightly along the -Z-axis direction.
[0070] Figure 8 is a schematic flowchart illustrating an example of the contact process S1. In this contact process S1, the drive unit 52 first drives the first motor and the second motor to perform at least one first drive process (step S11). The number of times the first drive process is performed in step S11 is stored in advance in, for example, the memory unit 50.
[0071] In this case, if the surface 13a of the dressing board 13 and the lower end of the cutting blade 40 come into contact during the first drive process, the current supplied to the first motor changes over time. If the maximum value of the current supplied to the first motor, which changes over time during the first drive process, falls below a threshold value stored in the storage unit 50 (step S12: NO), the determination unit 54 determines that the surface 13a of the dressing board 13 and the lower end of the cutting blade 40 did not come into contact during the first drive process.
[0072] Furthermore, if the determination unit 54 makes such a determination, the drive unit 52 drives the third motor to perform one second drive process (step S13), and then drives the first motor and the second motor again to perform step S11. In addition, the drive unit 52 drives the first motor, the second motor and the third motor so as to repeat steps S13 and S11 until the maximum value of the current supplied to the first motor, which changes over time in the first drive process, exceeds a threshold value stored in the storage unit 50.
[0073] Then, if the maximum value of the current supplied to the first motor, which changes over time during the first drive process, exceeds a threshold value stored in the memory unit 50 (step S12: YES), the determination unit 54 determines that the surface 13a of the dressing board 13 and the lower end of the cutting blade 40 have come into contact during the first drive process. As a result, the contact process S1 is completed and the shaping process S2 is performed.
[0074] Figure 9 is a schematic flowchart illustrating an example of the shaping process S2. In this shaping process S2, the drive unit 52 first drives the first motor and the second motor to perform the first drive process more times than in step S11 (step S21). The number of times the first drive process is performed in step S21 is stored in advance in the memory unit 50, for example.
[0075] Then, if the cumulative number of times the first or second drive process performed in the shaping process S2 is less than a predetermined number (step S22: NO), the drive unit 52 drives the third motor to perform the second drive process once (step S23), and then drives the first and second motors again to perform step S21. This predetermined number is stored, for example, in the storage unit 50.
[0076] Furthermore, the drive unit 52 drives the first motor, second motor, and third motor to repeat steps S23 and S21 until the number of times this cumulative calculation is performed reaches a predetermined number. When the number of times this cumulative calculation is performed reaches the predetermined number (step S22: YES), the shaping process S2 is completed, that is, the method for shaping the cutting blade 40 shown in Figure 5 is completed.
[0077] In the method described above, when the maximum value of the current supplied to the first motor, which changes over time during the first drive process, exceeds a threshold value stored in the memory unit 50, it is determined that the surface 13a of the dressing board 13 and the lower end of the cutting blade 40 have come into contact.
[0078] In this case, the number of times the first drive process is repeated in the contact process S1 can be reduced to the number of times the first drive process is repeated in the shaping process S2. As a result, this method makes it possible to suppress the prolonged time required for shaping the cutting blade 40.
[0079] The method described above is one aspect of the present invention, and the method of the present invention is not limited to the method described above. For example, the contact step S1 included in the method of the present invention is not limited to the one shown in Figure 8. Figure 10 is a flowchart schematically showing an example of a contact step S1 different from the contact step S1 shown in Figure 8.
[0080] Specifically, in the contact process S1 shown in Figure 10, the current supplied to the second motor, rather than the current supplied to the first motor, is used to determine whether or not the surface 13a of the dressing board 13 and the lower end of the cutting blade 40 have come into contact.
[0081] In other words, in the contact process S1 shown in Figure 10, step S12 shown in Figure 8 is replaced by step S14, which determines whether the maximum value of the current supplied to the second motor, which changes over time in the first drive process, exceeds a threshold value stored in the storage unit 50.
[0082] Furthermore, the shaping step S2 included in the method of the present invention is not limited to that shown in Figure 9. Figures 11 and 12 are flowcharts schematically showing examples of shaping steps S2 that are different from the shaping step S2 shown in Figure 9.
[0083] Specifically, in the shaping process S2 shown in Figure 11, the first drive process is continuously repeated after the completion of step S21 until it is determined that the surface 13a of the dressing board 13 and the lower end of the cutting blade 40 are no longer in contact.
[0084] In other words, in the shaping process S2 shown in Figure 11, if the maximum value of the current supplied to the first motor, which changes over time in the first drive process performed last in step S21, exceeds a threshold value stored in the memory unit 50 (step S24: NO), the determination unit 54 determines that the surface 13a of the dressing board 13 and the lower end of the cutting blade 40 came into contact in the first drive process.
[0085] The threshold used in step S24 may be the same as or different from the threshold used in step S12 shown in Figure 8. If the determination unit 54 makes such a determination, the drive unit 52 drives the first motor and the second motor so as to repeat the first drive process until the maximum value of the current supplied to the first motor, which changes over time in the first drive process, falls below the threshold (step S25).
[0086] Then, if the determination unit 54 determines that the surface 13a of the dressing board 13 and the lower end of the cutting blade 40 have come into contact during the first driving process, step S22 is performed. Steps S22 and beyond are as described with reference to Figure 9, so the above explanation will be used here.
[0087] In the shaping process S2 shown in Figure 11, the second drive process is performed when it is determined that the surface 13a of the dressing board 13 and the lower end of the cutting blade 40 are no longer in contact. Therefore, in this shaping process S2, it is possible to prevent the first drive process from being performed when the surface 13a of the dressing board 13 and the lower end of the cutting blade 40 are not in contact at all, or when not only the outer peripheral end of the cutting blade 40 but also the part inside the outer peripheral end is in contact with the surface 13a of the dressing board 13.
[0088] Furthermore, in the shaping process S2 shown in Figure 12, the current supplied to the second motor, rather than the current supplied to the first motor, is used to determine whether or not the surface 13a of the dressing board 13 and the lower end of the cutting blade 40 are no longer in contact.
[0089] In other words, in the shaping process S2 shown in Figure 12, step S24 shown in Figure 11 is replaced by step S26, which determines whether the maximum value of the current supplied to the second motor, which changes over time in the first drive process, exceeds a threshold value stored in the memory unit 50, and step S25 shown in Figure 11 is replaced by step S27, in which the drive unit 52 drives the first motor and the second motor so that the first drive process is repeated until the maximum value of the current supplied to the second motor, which changes over time in the first drive process, falls below the threshold value. The threshold value used in step S26 may be the same as or different from the threshold value used in step S14 shown in Figure 10.
[0090] Furthermore, the structure of the cutting device used in the present invention is not limited to the structure of the cutting device 2 described above. For example, the present invention may be implemented using a cutting device that is provided with Y-axis and Z-axis movement mechanisms for moving the holding table 10 along the Y-axis and Z-axis directions, respectively, and an X-axis movement mechanism for moving the cutting unit 36 along the X-axis direction.
[0091] Furthermore, the structures and methods of the embodiments described above can be modified as appropriate without departing from the scope of the present invention. [Explanation of Symbols]
[0092] 2:Cutting device 4: Base (4a: Recess) 6: Table cover 8: Dustproof and waterproof cover 10: Chuck table (10a: frame, 10b: porous plate) 11: Frame Unit 12: Clamp 13: Dressing board (13a: front side, 13b: back side) 15: Tape 16: Support structure (16a: standing part, 16b: arm part) 17: Frame 18:Y-axis direction movement mechanism 20: Y-axis guide rail 22: Y-axis movement plate 24: Screw shaft 26:Z-axis direction movement mechanism 28: Z-axis guide rail 30: Z-axis movement plate 32: Screw shaft 34: Motor (Third Motor) 36: Cutting Unit 38: Spindle Housing 40: Cutting blade (40a: Cutting edge) 42: Spindle 44: Measurement Unit 46: Control Unit 48: Processing Unit 50: Storage section 52: Drive unit 54: Judgment section
Claims
1. A cutting apparatus comprising: a holding table that holds a dressing board on its upper surface; a spindle that extends along a first direction parallel to the upper surface of the holding table and has an annular cutting blade attached to its tip; a first motor for rotating the spindle with a straight line along the first direction as the axis of rotation; a second motor for moving the holding table or the spindle along the first direction or a second direction opposite to the first direction; and a third motor for moving the holding table or the spindle along a third direction perpendicular to the upper surface of the holding table or a fourth direction opposite to the third direction, wherein a method for shaping a cutting blade is provided. A contact step of moving the holding table and the spindle relative to each other so that the surface of the dressing board and the lower end of the cutting blade come into contact, A shaping step is provided in which, after it is determined that the surface of the dressing board and the lower end of the cutting blade have come into contact, the holding table and the spindle are moved relative to each other to shape the cutting blade. Each of the contact process and the shaping process is, A first driving step involves driving the first motor to rotate the spindle at a constant rotational speed, while driving the second motor to move the tip of the spindle over the dressing board at a constant speed, The process includes a second drive step of driving the third motor to bring the tip of the spindle closer to the dressing board, In the contact process, at least one first drive process and one second drive process are repeatedly performed alternately. In the shaping process, the first drive process is performed more times than the number of times the first drive process is performed continuously in the contact process, and the second drive process is performed once, and these are repeated alternately. A method for shaping a cutting blade, wherein, in the first drive step of the contact step, it is determined that the surface of the dressing board and the lower end of the cutting blade have come into contact when the maximum value of the current supplied to the first motor, which changes over time, exceeds a first threshold.
2. A cutting apparatus comprising: a holding table that holds a dressing board on its upper surface; a spindle that extends along a first direction parallel to the upper surface of the holding table and has an annular cutting blade attached to its tip; a first motor for rotating the spindle with a straight line along the first direction as the axis of rotation; a second motor for moving the holding table or the spindle along the first direction or a second direction opposite to the first direction; and a third motor for moving the holding table or the spindle along a third direction perpendicular to the upper surface of the holding table or a fourth direction opposite to the third direction, wherein a method for shaping a cutting blade is provided. A contact step of moving the holding table and the spindle relative to each other so that the surface of the dressing board and the lower end of the cutting blade come into contact, A shaping step is provided in which, after it is determined that the surface of the dressing board and the lower end of the cutting blade have come into contact, the holding table and the spindle are moved relative to each other to shape the cutting blade. Each of the contact process and the shaping process is, A first driving step involves driving the first motor to rotate the spindle at a constant rotational speed, while driving the second motor to move the tip of the spindle over the dressing board at a constant speed, The process includes a second drive step of driving the third motor to bring the tip of the spindle closer to the dressing board, In the contact process, at least one first drive process and one second drive process are repeatedly performed alternately. In the shaping process, the first drive process is performed more times than the number of times the first drive process is performed continuously in the contact process, and the second drive process is performed once, and these are repeated alternately. A method for shaping a cutting blade, wherein, in the first drive step of the contact step, it is determined that the surface of the dressing board and the lower end of the cutting blade have come into contact when the maximum value of the current supplied to the second motor, which changes over time, exceeds a first threshold.
3. In the shaping process, the first drive step is repeated continuously until it is determined that the surface of the dressing board and the lower end of the cutting blade are no longer in contact, after which the second drive step is performed. A method for shaping a cutting blade according to claim 1 or 2, wherein, in the first drive step of the shaping step, it is determined that the surface of the dressing board and the lower end of the cutting blade are no longer in contact when the maximum value of the current supplied to the first motor, which changes over time, falls below a second threshold.
4. In the shaping process, the first drive step is repeated continuously until it is determined that the surface of the dressing board and the lower end of the cutting blade are no longer in contact, after which the second drive step is performed. A method for shaping a cutting blade according to claim 1 or 2, wherein, in the first drive step of the shaping step, it is determined that the surface of the dressing board and the lower end of the cutting blade are no longer in contact when the maximum value of the current supplied to the second motor, which changes over time, falls below a second threshold.