JP7486333B2 - Setup method using a gauge block - Google Patents

Description

The present invention relates to a setup method using a block gauge.

In a grinding process in which a grinding wheel is used to grind a workpiece held on the holding surface of a chuck table, a setup is performed in which the height of the grinding wheel when the bottom surface of the grinding wheel is brought into contact with the holding surface of the chuck table is stored in the processing device. By using the height of the grinding wheel stored in the setup and the thickness of the workpiece, the grinding wheel can be quickly positioned at the grinding start position, where the bottom surface of the grinding wheel comes into contact with the top surface of the workpiece held on the holding surface.
In the setup, as disclosed in Patent Document 1, a block gauge with a known thickness is inserted between the holding surface and the underside of the grinding wheel, and the height position of the grinding wheel when the gap is just large enough for the block gauge to enter is stored in the device, and the stored position of the grinding wheel may vary due to differences in operators, etc. In order to reduce this variation, the setup is performed using a stepped block gauge with at least two steps formed by connecting a block gauge of a given thickness to a block gauge of another thickness.

In the setup, for example, the height of the grinding wheel when the first step of a stepped block gauge can enter the gap between the holding surface and the underside of the grinding wheel, but the second step cannot enter the gap, is stored.
This allows the height of the grinding wheel to be stored within the difference in height between the first and second stages regardless of which operator performs the setup, preventing the position of the grinding wheel stored from differing significantly depending on the operator. However, there is variation in the height of the grinding wheel stored by operators within that range of the difference in height.

JP 2008-087104 A

If there is variation in the stored height of the grinding wheel, not only will it take unnecessary time for the bottom surface of the grinding wheel to come into contact with the top surface of the workpiece, but when the grinding wheel is positioned at the start position for grinding, the bottom surface of the grinding wheel will come into contact with the top surface of the workpiece, causing damage to the workpiece.
Therefore, when using a gauge block for setup, there is a problem to be solved: how to minimize errors.

The present invention relates to a setup method for a processing apparatus including a chuck table having a holding surface for holding a workpiece, processing means for processing the workpiece held on the holding surface using a processing tool, and moving means for moving the processing tool in a direction perpendicular to the holding surface, the method comprising: bringing the processing tool close to the chuck table and measuring the distance between the holding surface and the tip of the processing tool, thereby storing the position of the processing tool when the tip of the processing tool comes into contact with the holding surface; moving the processing tool in a direction approaching the chuck table using the moving means to form a gap between the holding surface and the tip of the processing tool, and using a first block gauge having a predetermined thickness that can enter the gap, and a second block gauge having a predetermined thickness that cannot enter the gap, This setup method includes a confirmation step of confirming that the first block gauge can enter the gap but the second block gauge cannot enter it by using a second block gauge having a predetermined thickness that is thicker than the first block gauge; a second gap forming step of bringing the processing tool closer to the holding surface by a distance that is half the difference in thickness between the second block gauge and the first block gauge to form a second gap between the holding surface and the tip of the processing tool; and a storage step of storing the position of the processing tool in a memory unit if the first block gauge can enter the second gap formed by the second gap forming step, and storing the position of the processing tool positioned in the confirmation step in the memory unit if the first block gauge cannot enter the second gap.
The present invention relates to a setup method for a processing apparatus including a chuck table having a holding surface for holding a workpiece, processing means for processing the workpiece held on the holding surface using a processing tool, and moving means for moving the processing tool in a direction perpendicular to the holding surface, the method comprising: bringing the processing tool close to the chuck table and measuring the distance between the holding surface and the tip of the processing tool, thereby storing the position of the processing tool when the tip of the processing tool comes into contact with the holding surface; the method includes a confirmation step of using a first block gauge having a predetermined thickness that can enter the gap and a second block gauge having a predetermined thickness thicker than the first block gauge that cannot enter the gap, and a confirmation step of confirming that the first block gauge can enter the gap but the second block gauge cannot enter the gap; and a confirmation step of confirming that the second block gauge and the first block gauge are in a predetermined thickness and that the first block gauge and the second block gauge are in a predetermined thickness and ... the second block gauge and the first block gauge are in a predetermined thickness and the second block gauge and the first block gauge are in a predetermined thickness and the second block gauge and the first block gauge are in a predetermined thickness and the second block gauge and the first block gauge are in a predetermined thickness and the second block gauge and the first block gauge are in a predetermined thickness and the second block gauge a second gap forming step of bringing the processing tool closer to the holding surface by a distance half the thickness difference between the holding surface and the tip of the processing tool; and a storage step of bringing the processing tool closer to the holding surface from a position where the first block gauge can enter the second gap formed by the second gap forming step, if the first block gauge can enter the second gap, or from a position where the processing tool is moved away from the holding surface by the previous movement distance by which the processing tool was brought closer to the holding surface, by a distance half the movement distance by which the processing tool was brought closer to the holding surface last time, if the first block gauge cannot enter the second gap , and checking whether the first block gauge can enter between the holding surface and the tip of the processing tool after the processing tool has been brought closer to the holding surface, until the first block gauge cannot enter between the holding surface and the tip of the processing tool, and finally storing in the storage unit the position of the processing tool when the first block gauge can enter between the holding surface and the tip of the processing tool.

By using this setup method, it is possible to mechanically narrow the gap between the holding surface and the tip of the tool. This reduces setup errors that occur when different operators perform the setup.

FIG. 2 is a perspective view showing the entire processing device. This is a cross-sectional side view showing how to set up using a staircase block gauge. 1 is a flow chart showing a setup flow. 1A is a cross-sectional view showing the tip of the processing tool positioned at a first height position, and FIG. 1B is a cross-sectional view showing the tip of the processing tool positioned at a second height position. 11 is a table showing the relationship between the height position of the tip of the processing tool when the processing tool is moved and the distance between the holding surface of the chuck table and the tip of the processing tool. 1A is a cross-sectional view showing the tip of the processing tool positioned at a second height position, and FIG. 1B is a cross-sectional view showing the tip of the processing tool positioned at a third height position. 1A is a cross-sectional view showing the tip of the processing tool positioned at a third height position, and FIG. 1B is a cross-sectional view showing the tip of the processing tool positioned at a fourth height position. 1A is a cross-sectional view showing the tip of the processing tool positioned at a third height position, and FIG. 1B is a cross-sectional view showing the tip of the processing tool positioned at a fifth height position. 1A is a cross-sectional view showing the tip of the processing tool positioned at a fifth height position, and FIG. 1B is a cross-sectional view showing the tip of the processing tool positioned at a sixth height position.

1 Processing Apparatus The processing apparatus 1 shown in Fig. 1 is a processing apparatus that processes a workpiece 13 using processing means 3. The processing apparatus 1 will be described below.

As shown in FIG. 1, the processing device 1 includes a base 10 extending in the Y-axis direction and a column 11 erected on the +Y-direction side of the base 10.

A moving means 4 that supports the processing means 3 so that it can be raised and lowered is disposed on the -Y direction side surface of the column 11. The processing means 3 includes a spindle 30 having a rotation axis 35 in the Z axis direction, a housing 31 that rotatably supports the spindle 30, a spindle motor 32 that rotates and drives the spindle 30 around the rotation axis 35, an annular mount 33 connected to the lower end of the spindle 30, and a processing tool 34 detachably attached to the lower surface of the mount 33.
The processing tool 34 is, for example, a grinding wheel, and includes a wheel base 341 and a plurality of grinding stones 340, each having a substantially rectangular parallelepiped shape, arranged in a ring shape on the lower surface of the wheel base 341. A tip 342 of the grinding stone 340 forms a grinding surface that comes into contact with the workpiece 13.

The moving means 4 includes a ball screw 40 having a rotating shaft 45 in the Z-axis direction, a pair of guide rails 41 arranged parallel to the ball screw 40, a Z-axis motor 42 that rotates the ball screw 40 around the rotating shaft 45, an encoder 420 that measures and controls the amount of rotation of the Z-axis motor 42, a lifting plate 43 whose internal nut is screwed onto the ball screw 40 and whose side is in sliding contact with the guide rail 41, and a holder 44 that is connected to the lifting plate 43 and supports the processing means 3.

When the ball screw 40 is driven by the Z-axis motor 42 and rotates around the rotation shaft 45, the lift plate 43 moves up and down along the Z-axis guided by the guide rail 41, and the processing tool 34 of the processing means 3 held by the holder 44 moves in a direction perpendicular to the holding surface 200 (Z-axis direction).

A storage unit 421 that stores the height position of the processing tool 34 is connected to the encoder 420. The amount of rotation of the Z-axis motor 42 measured by the encoder 420 is converted into the amount of movement of the processing tool 34 in the Z-axis direction and stored in the storage unit 421.
The minimum resolution of the movement amount in the Z-axis direction of the moving means 4 is, for example, 0.1 μm.

A chuck table 2 is disposed on the base 10. The chuck table 2 includes a disk-shaped suction portion 20 and an annular frame 21 that supports the suction portion 20. The upper surface of the suction portion 20 is a holding surface 200 on which the workpiece 13 is held, and an upper surface 210 of the frame 21 is formed flush with the holding surface 200.
Suction means or the like (not shown) is connected to the holding surface 200. When the workpiece 13 is placed on the holding surface 200, a suction force is generated using the suction means or the like (not shown), and the generated suction force is transmitted to the holding surface 200, so that the workpiece 13 can be suction-held on the holding surface 200.

A cover 27 and a bellows 28 connected to the cover 27 so as to be freely stretchable are disposed around the chuck table 2. For example, when the chuck table 2 moves in the Y-axis direction, the cover 27 moves in the Y-axis direction together with the chuck table 2, causing the bellows 28 to stretch.

A staircase block gauge 8 can be placed on the holding surface 200 of the chuck table 2 of the processing device 1. The staircase block gauge 8 includes a first block gauge 81 having a thickness 811, and a second block gauge 82 connected to the first block gauge 81 and having a thickness 821 that is thicker than the first block gauge 81 by a thickness difference 61. The thickness 811 of the first block gauge 81 is, for example, 2 μm, and the thickness difference 61 is, for example, 20 μm.
In addition, the staircase block gauge 8 may be formed by stacking a block gauge with a thickness difference of 61 on top of the first block gauge 81 to form the thickness 821 of the second block gauge 82.
By using the moving means 4 to move the processing tool 34 in a direction approaching the chuck table 2, an attempt is made to insert the staircase block gauge 8 into the gap formed between the holding surface 200 and the tip 342 of the processing tool 34, thereby making it possible to confirm whether the first block gauge 81 and the second block gauge 82 can each enter between the tip 342 of the processing tool 34 and the holding surface 200.

As shown in FIG. 2, the chuck table 2 includes a base 22 that supports a frame 21, and three support columns 23 (two of which are shown in FIG. 2) that support the base 22.
A rotating means 24 that rotates the base 22 about a rotation shaft 25 in the Z-axis direction is connected to the lower part of the base 22. When the base 22 is driven by the rotating means 24 to rotate about the rotation shaft 25, the chuck table 2 supported by the base 22 also rotates about the rotation shaft 25.

The processing device 1 includes an internal base 100 extending in the Y-axis direction. A Y-axis moving means 5 for moving the chuck table 2 in the Y-axis direction is disposed on the internal base 100.
The Y-axis moving means 5 includes a ball screw 50 having a rotation axis 55 in the Y-axis direction, a guide rail 51 arranged parallel to the ball screw 50, and a movable plate 53 having a nut 54 connected to the bottom thereof screwed onto the ball screw 50 and reciprocating in the Y-axis direction along the guide rail 51. A support pillar 23 is erected on the movable plate 53, and the movable plate 53 supports the chuck table 2 via the support pillar 23.
The Y-axis moving means 5 also includes a Y-axis motor (not shown) that rotates the ball screw 50 around the rotation shaft 55 as an axis.
When the ball screw 50 is rotated by a Y-axis motor or the like (not shown), the movable plate 53 moves in the Y-axis direction while being guided by the guide rail 51, and the chuck table 2 supported via the support pillar 23 moves in the Y-axis direction.

When grinding the workpiece 13 using the processing device 1, first, the workpiece 13 is placed on the holding surface 200 of the chuck table 2, and a suction source (not shown) is activated. This generates a suction force that is transmitted to the holding surface 200, and the workpiece 13 is held by suction on the holding surface 200.

Then, with the workpiece 13 being suction-held on the holding surface 200 , the chuck table 2 is moved in the +Y direction using the Y-axis moving means 5 until it is positioned below the processing means 3 .
Next, the chuck table 2 is rotated around the rotating shaft 25 using the rotating means 24, thereby rotating the workpiece 13 held on the holding surface 200, and the grinding wheel 340 is rotated around the rotating shaft 35 using the spindle motor 32.

With the workpiece 13 rotating about the rotation axis 25 and the grinding wheel 340 rotating about the rotation axis 35, the grinding wheel 340 is lowered in the -Z direction using the moving means 4, and the tip 342 of the grinding wheel 340 is brought into contact with the top surface 130 of the workpiece 13. With the tip 342 in contact with the top surface 130 of the workpiece 13, the grinding wheel 340 is further lowered in the -Z direction, thereby grinding the workpiece 13.

2. Setup Method Using Block Gauge (1) Confirmation Process The following describes a setup method for storing the height position of the processing tool 34 of the processing device 1 in the memory unit 421 using the above-mentioned staircase block gauge 8. The setup using the staircase block gauge 8 is performed according to the flowchart shown in FIG.

First, the processing tool 34 is moved in a direction approaching the chuck table 2 (-Z direction) by using the moving means 4 shown in FIG.
4A, the height position of the tip 342 of the processing tool 34 is positioned at the first height position 71, and a first gap 91 is formed between the holding surface 200 and the tip 342 of the processing tool 34. The first gap 91 is, for example, 18.4 μm.

After forming a first gap 91 between the holding surface 200 and the tip 342 of the processing tool 34, the staircase block gauge 8 is inserted into the first gap 91. This confirms that the first block gauge 81 can enter the first gap 91, but the second block gauge 82 cannot enter the first gap 91.

Here, when the staircase block gauge 8 enters the formed gap, if not only the first block gauge 81 but also the second block gauge 82 can enter the gap, the staircase block gauge 8 is temporarily removed from the gap, and then the processing tool 34 is brought closer to the chuck table 2 to adjust the size of the gap between the holding surface 200 and the tip 342 of the processing tool 34, and the staircase block gauge 8 is again inserted into the gap to check whether the second block gauge 82 can enter.
In the confirmation process, for example, the above adjustment is repeated until the gap between the holding surface 200 and the tip 342 of the processing tool 34 becomes large enough that the first block gauge 81 can enter into the gap but the second block gauge 82 cannot, and the process is terminated when it is confirmed that the first block gauge 81 can enter into the gap but the second block gauge 82 cannot.

(2) Storage process (a) Repeat process After the confirmation process is completed, the staircase block gauge 8 that has entered the first gap 91 is removed from the first gap 91. Then, as shown in FIG. 4B, the processing tool 34 is brought closer to the holding surface 200 by a distance 62 (10 μm) that is half the thickness difference 61 between the second block gauge 82 and the first block gauge 81. As a result, the tip 342 of the processing tool 34 is positioned at the second height position 72, and a second gap 92 is formed between the holding surface 200 and the tip 342 of the processing tool 34. Here, the second gap 92 is 8.4 μm obtained by subtracting the distance 62, 10 μm, from the first gap 91, 18.4 μm.
Figure 5 shows a table showing the relationship between the height position of the tip 432 of the processing tool 34 when the processing tool 34 is gradually approached to the holding surface 200 and the distance between the holding surface 200 of the chuck table 2 and the tip 342 of the processing tool 34.

After the processing tool 34 is brought close to the holding surface 200, it is confirmed whether the first block gauge 81 can enter. Since the second gap 92 is larger than the thickness 811 of the first block gauge 81, the first block gauge 81 can enter the second gap 92 as shown in FIG. 4(b).

The second height position 72 where the processing tool 34 is positioned is a height position higher than the step quarter position 702, which is a height position that is a distance 63 higher than the height position 700 of the upper surface 810 of the first block gauge 81, as shown in FIG. 6(a). The distance 63 is half the travel distance 62, and is 5 μm, which is one-fourth of the thickness difference 61.

From a state in which the tip 342 of the processing tool 34 is positioned at the second height position 72, the processing tool 34 is moved closer to the holding surface 200 by 5 μm, which is a distance 63 that is half the movement distance 62 of the processing tool 34 when the processing tool 34 was last moved closer to the holding surface 200. As a result, as shown in FIG. 6B, the tip 342 of the processing tool 34 is positioned at the third height position 73, and a third gap 93 is formed between the holding surface 200 and the tip 342 of the processing tool 34.
Here, the third gap 93 is 3.4 μm, which is obtained by subtracting the distance 62 of 5 μm from the second gap 92 of 8.4 μm.

Then, it is confirmed whether the first block gauge 81 can enter the third gap 93. Because the third gap 93 is larger than the thickness 811 of the first block gauge 81, the first block gauge 81 can enter the third gap 93, as shown in FIG. 6(b).

The third height position 73 is a height position higher than the step 80% position 703, which is a height position that is a distance 64 higher than the height position 700 of the upper surface 810 of the first block gauge 81, as shown in Figure 7 (a).
After the above repeating process, the tip 342 of the processing tool 34 is moved from the state in which it is positioned at the third height position 73 toward the holding surface 200 by 2.5 μm, which is half the movement distance 63 of the processing tool 34 when it was last moved toward the holding surface 200 and is a distance 64 equivalent to one-eighth of the thickness difference 61. As a result, as shown in FIG. 7B, the tip 342 of the processing tool 34 is positioned at the fourth height position 74, and a fourth gap 94 is formed between the holding surface 200 and the tip 342 of the processing tool 34.
Here, the fourth gap 94 is 0.9 μm, which is obtained by subtracting the distance 64 of 2.5 μm from the third gap 93 of 3.4 μm.

Then, check whether the first block gauge 81 can enter the eighth gap 98. Because the fourth gap 94 is smaller than the thickness 811 of the first block gauge 81, the first block gauge 81 cannot enter the fourth gap 94, as shown in FIG. 7(b).

(B) Separation step: When the first block gauge 81 cannot be inserted, the processing tool 34 is moved away from the holding surface 200 by the distance 64 by which the processing tool 34 was previously moved closer to the holding surface 200. This returns the tip 342 of the processing tool 34 to the third height position 73 as shown in FIG. 8(a).

(C) Second repeating process (A) Descending step Then, after the separating process, with the tip 342 of the processing tool 34 positioned at the third height position 73, the processing tool 34 is lowered by 1.3 μm, which is half the distance 64 by which the processing tool 34 was last moved closer, or 1.25 μm rounded up to one decimal place.
8B, the tip 342 of the processing tool 34 is positioned at the fifth height position 75, and a fifth gap 95 is formed between the holding surface 200 and the tip 342 of the processing tool 34. The fifth gap 95 is 2.1 μm obtained by subtracting 1.3 μm from the third gap 93 of 3.4 μm.

(B) Determination Step After the descending step, it is determined whether or not the first block gauge 81 can enter between the tip 342 of the processing tool 34 and the holding surface 200.
Since the fifth gap 95 is larger than the thickness 811 of the first block gauge 81 , the first block gauge 81 can be inserted between the tip 342 of the processing tool 34 and the holding surface 200 .

Next, the lowering step is performed again. That is, as shown in FIG. 9(a), in a state where the fifth gap 95 is formed between the holding surface 200 and the tip 342 of the processing tool 34, the processing tool 34 is lowered by 0.7 μm, which is half the distance 66 of the distance 65 by which the processing tool 34 was last approached to the holding surface 200, that is, 0.65 μm rounded up to the first decimal place. As a result, as shown in FIG. 9(b), the tip 342 of the processing tool 34 is positioned at the sixth height position 76, and a sixth gap 96 is formed between the holding surface 200 and the tip 342 of the processing tool 34. The sixth gap 96 is 1.4 μm, which is 0.7 μm less than the fifth gap 95 of 2.1 μm.

Then, the judgment step is performed again. That is, it is judged whether the first block gauge 81 can enter between the tip 342 of the processing tool 34 and the holding surface 200. Since the sixth gap 96 is smaller than the thickness 811 of the first block gauge 81, the first block gauge 81 cannot enter between the tip 342 of the processing tool 34 and the holding surface 200. Therefore, the second repeating process is terminated.

Then, the processing tool 34 is raised from the sixth height position 76, which is the height position of the processing tool 34 immediately after the second repeat process is completed, by the movement distance by which the processing tool 34 was last moved closer to the holding surface 200, i.e., by a distance of 66, and the fifth height position 95, which is the height position of the processing tool 34 when the processing tool 34 is moved away from the holding surface 200, is stored in the memory unit 421.

By performing setup using this setup method, the distance between the holding surface 200 and the tip 342 of the processing tool 34 can be mechanically narrowed. This can reduce setup errors caused by different operators performing setup. In addition, the amount of descent of the processing tool 34 is gradually reduced to half, one-quarter, one-eighth, and so on, of the thickness 821 of the second block gauge 82, so that setup errors can be further reduced.
Furthermore, by narrowing the gap between the holding surface 200 and the tip 342 of the processing tool 34, it is possible to shorten the time from when the processing tool 34 starts to approach the top surface 130 of the workpiece 13 until the tip 342 of the processing tool 34 comes into contact with the top surface 130 of the workpiece 13 during grinding of the workpiece 13. This makes it possible to reduce the time required for grinding.
In order to facilitate handling of the staircase block gauge 8, the thickness 811 of the first step, i.e., the first block gauge 81, may be, for example, 5.00 mm instead of 2 μm.

1: Processing device 10: Base 100: Internal base 11: Column 2: Chuck table 20: Suction part 200: Holding surface 21: Frame 210: Frame upper surface 22: Base 23: Support column 24: Rotation means 25: Rotation shaft 27: Cover 28: Bellows 3: Processing means 30: Spindle 31: Housing 32: Spindle motor 33: Mount 34: Processing tool 340: Grinding wheel 342: Tip of processing tool (grinding surface)
341: Wheel base 35: Rotating shaft 4: Moving means 40: Ball screw 41: Guide rail 42: Z-axis motor 420: Encoder 43: Lift plate 44: Holder 45: Rotating shaft 5: Y-axis moving means 50: Ball screw 51: Guide rail 53: Movable plate 54: Nut 55: Rotating shaft 421: Memory unit 8: Staircase block gauge 81: First block gauge 810: Top surface of first block gauge 82: Second block gauge 820: Top surface of second block gauge 13: Workpiece 130: Top surface of workpiece 811: Thickness of first block gauge 821: Thickness of second block gauge 61-66: Travel distance of processing tool 71-76: Height position of tip of processing tool 700: Height position of top surface of first block gauge 701: Center position of step 702: Quarter position of step 703: 80% of the step 91-96: Gap between the holding surface and the tip of the processing tool

Claims (2)

A processing apparatus including a chuck table having a holding surface for holding a workpiece, a processing means for processing the workpiece held on the holding surface using a processing tool, and a moving means for moving the processing tool in a direction perpendicular to the holding surface,
A setup method for storing a position of the processing tool when the tip of the processing tool contacts the holding surface by bringing the processing tool close to the chuck table and measuring a distance between the holding surface and the tip of the processing tool, the setup method comprising:
a confirmation process in which the processing tool is moved in a direction approaching the chuck table using the moving means to form a gap between the holding surface and the tip of the processing tool, and a first block gauge having a predetermined thickness that can enter the gap and a second block gauge having a predetermined thickness thicker than the first block gauge that cannot enter the gap are used to confirm that the first block gauge can enter the gap but the second block gauge cannot enter the gap;
a second gap forming step of bringing the processing tool closer to the holding surface by a distance half the thickness difference between the second block gauge and the first block gauge to form a second gap between the holding surface and the tip of the processing tool;
a storage step of storing the position of the processing tool in a storage unit if the first block gauge can enter the second gap formed by the second gap forming step, and storing the position of the processing tool positioned in the confirmation step in the storage unit if the first block gauge cannot enter the second gap;
A setup method comprising: A processing apparatus including a chuck table having a holding surface for holding a workpiece, a processing means for processing the workpiece held on the holding surface using a processing tool, and a moving means for moving the processing tool in a direction perpendicular to the holding surface,
A setup method for storing a position of the processing tool when the tip of the processing tool contacts the holding surface by bringing the processing tool close to the chuck table and measuring a distance between the holding surface and the tip of the processing tool, the setup method comprising:
a confirmation process in which the processing tool is moved in a direction approaching the chuck table using the moving means to form a gap between the holding surface and the tip of the processing tool, and a first block gauge having a predetermined thickness that can enter the gap and a second block gauge having a predetermined thickness thicker than the first block gauge that cannot enter the gap are used to confirm that the first block gauge can enter the gap but the second block gauge cannot enter the gap;
a second gap forming step of bringing the processing tool closer to the holding surface by a distance half the thickness difference between the second block gauge and the first block gauge to form a second gap between the holding surface and the tip of the processing tool;
If the first block gauge can enter the second gap formed by the second gap forming step, from that position,
If the first block gauge cannot enter the second gap, the tool is moved away from the holding surface by the same distance as the tool was moved toward the holding surface just before.
the processing tool is brought close to the holding surface by a distance half the distance by which the processing tool was brought close to the holding surface immediately before, and confirmation is made as to whether or not the first block gauge can enter between the holding surface and the tip of the processing tool after the processing tool is brought close to the holding surface , and this is repeated until the first block gauge can no longer enter between the holding surface and the tip of the processing tool;
a storing step of storing in the memory unit a position of the processing tool when the first block gauge is able to enter between the holding surface and the tip of the processing tool;
A setup method comprising:

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