JP7827566B2 - Automatic exchange device - Google Patents

Description

The present invention relates to an automatic changer connected to a cutting device.

Wafer surfaces are divided into multiple IC, LSI, and other devices along planned division lines. These are then separated into individual device chips using a cutting machine, and each device chip is used in electrical equipment such as mobile phones and personal computers.

The cutting device comprises a chuck table with a holding surface for holding the wafer, cutting means having a cutting blade attached with a fixing nut for cutting the wafer held on the chuck table, X-axis feed means for processing the chuck table in the X-axis direction, Y-axis feed means for indexing and feeding the cutting means in the Y-axis direction perpendicular to the X-axis direction, and Z-axis feed means for cutting and feeding the cutting means in the Z-axis direction perpendicular to the X-axis and Y-axis directions. The holding surface is defined in the X-axis and Y-axis directions, allowing the wafer to be divided into individual device chips with high precision.

The applicant has also proposed an automatic blade changer that can automatically change cutting blades attached to cutting means (see, for example, Patent Document 1).

Japanese Patent Application Laid-Open No. 2007-98536

However, the blade holder that attaches and detaches the cutting blade to and from the rotating shaft of the cutting means can become increasingly dirty as used cutting blades are repeatedly detached from the rotating shaft, which can make it impossible to securely hold the cutting blade.

In addition, used cutting blades tend to become dirty on the front or back, and dirt, particularly on the back, can make it impossible to read the ID (barcode, QR code (registered trademark)) that indicates the characteristics of the cutting blade.

The objective of the present invention is to provide an automatic blade replacement device that can securely hold cutting blades even when they are repeatedly replaced, and that can keep the cutting blade ID readable.

According to the present invention, there is provided the following automatic exchange device that solves the above problems:
"An automatic changer comprising a chuck table having a holding surface for holding a workpiece, cutting means having a cutting blade attached with a fixing nut for cutting the workpiece held on the chuck table, X-axis feed means for feeding the chuck table in the X-axis direction for processing, Y-axis feed means for indexing and feeding the cutting means in the Y-axis direction perpendicular to the X-axis direction, and Z-axis feed means for cutting and feeding the cutting means in the Z-axis direction perpendicular to the X-axis and Y-axis directions, wherein the holding surface is connected to a cutting device defined in the X-axis and Y-axis directions,
The cutting blade storage device includes at least a cutting blade storage means for storing a plurality of cutting blades, a carrying-in/out means for carrying cutting blades in and out of the cutting blade storage means, a Y-axis positioning means for positioning the carrying-in/out means at an operating position and a retracted position in the Y-axis direction relative to the cutting blade storage means, a Z-axis moving means for moving the carrying-in/out means in the Z-axis direction, an X-axis moving means for moving the carrying-in/out means in the X-axis direction to act on the cutting blades attached to the spindles of the cutting means, and a cleaning means.
The carry-in/out means includes a Z rotation shaft extending in the Z axis direction, a blade holding portion radially connected to the Z rotation shaft and suction-holding the cutting blade, and a fixing nut holding portion that screws the fixing nut onto and unscrews the male screw formed at the tip of the spindle,
The cleaning means is an automatic exchange device having a blade holder cleaning unit that cleans the blade holder, and a cutting blade cleaning unit that cleans the back side of the cutting blade held by the blade holder.

Preferably, the loading/unloading means is mounted on a frame via a bending arm, the frame is slidably supported on a guide rail extending in the Y-axis direction and mounted on a lifting table, and the Y-axis positioning means positions the loading/unloading means at the operating position and the retracted position in the Y-axis direction relative to the cutting blade storage means. It is preferable that the bending arm moves the loading/unloading means back and forth in the X-axis direction.

The cutting blade storage means preferably includes a drive gear having a rotational axis extending in the Y-axis direction, a driven gear spaced apart from the drive gear in the Z-axis direction and having a rotational axis extending in the Y-axis direction, a caterpillar loop wound around the drive gear and the driven gear, and a blade support shaft extending in the Y-axis direction that is disposed at a predetermined interval on the caterpillar loop and inserted into a central opening in the cutting blade to support the cutting blade. It is desirable that the distance between the drive gear and the driven gear in the Z-axis direction be adjustable, and the length of the caterpillar loop be adjustable.

The cutting blades stored in the cutting blade storage means are hub blades with cutting edges arranged on the outer periphery of the base, the blade support shaft has an outer diameter corresponding to the inner diameter of the central opening of the hub blade, and the blade holder preferably holds the hub blade.

The automatic exchange device of the present invention comprises:
an automatic changer comprising: a chuck table having a holding surface for holding a workpiece; cutting means having a cutting blade attached with a fixing nut for cutting the workpiece held on the chuck table; X-axis feed means for feeding the chuck table in an X-axis direction for processing; Y-axis feed means for indexing and feeding the cutting means in a Y-axis direction perpendicular to the X-axis direction; and Z-axis feed means for cutting and feeding the cutting means in a Z-axis direction perpendicular to the X-axis and Y-axis directions, wherein the holding surface is connected to a cutting device defined in the X-axis and Y-axis directions;
The cutting blade storage device includes at least a cutting blade storage means for storing a plurality of cutting blades, a carrying-in/out means for carrying cutting blades in and out of the cutting blade storage means, a Y-axis positioning means for positioning the carrying-in/out means at an operating position and a retracted position in the Y-axis direction relative to the cutting blade storage means, a Z-axis moving means for moving the carrying-in/out means in the Z-axis direction, an X-axis moving means for moving the carrying-in/out means in the X-axis direction to act on the cutting blades attached to the spindles of the cutting means, and a cleaning means.
The carry-in/out means includes a Z rotation shaft extending in the Z axis direction, a blade holding portion radially connected to the Z rotation shaft and suction-holding the cutting blade, and a fixing nut holding portion that screws the fixing nut onto and unscrews the male screw formed at the tip of the spindle,
The cleaning means has a blade holding part cleaning part that cleans the blade holding part, and a cutting blade cleaning part that cleans the back side of the cutting blade held by the blade holding part, so that even if the cutting blade is repeatedly replaced, the cutting blade can be securely held and the ID of the cutting blade can be kept in a readable state.

1 is a perspective view of an automatic changer constructed in accordance with the present invention; FIG. 2 is an exploded perspective view of the cutting blade storage means shown in FIG. 1 . FIG. 3 is a perspective view of the blade support shaft shown in FIG. 2 . FIG. 3 is a cross-sectional view of the blade support shaft shown in FIG. 2 . FIG. 2 is a perspective view of the loading/unloading means shown in FIG. 1 . FIG. 2 is an exploded perspective view of the frame, the lift table, and the base frame shown in FIG. 1 . FIG. 2 is an exploded perspective view of the frame shown in FIG. 1 . FIG. 2 is a perspective view of the cleaning means shown in FIG. 1 . FIG. 2 is a perspective view of a cutting device to which the automatic exchange device shown in FIG. 1 is connected. FIG. 10 is a perspective view of the chuck table shown in FIG. 9 . FIG. 10 is a perspective view of the cutting means shown in FIG. 9 . FIG. 12 is a perspective view of the cutting means in a state where the blade cover shown in FIG. 11 is opened. FIG. 10 is an exploded perspective view of the cutting means shown in FIG. 9 . 10 is a perspective view showing a state in which the automatic exchange device shown in FIG. 1 is connected to the cutting device shown in FIG. 9 . 2 is a perspective view showing a state in which the cutting blade storage means and the carrying-in/out means of the automatic blade changing device shown in FIG. 1 face each other; 16 is a perspective view showing a state in which the frame body has advanced from the state shown in FIG. 15 toward the cutting blade storage means. FIG. 17 is a perspective view showing a state in which the frame body is retracted from the state shown in FIG. 16 and the lift table is raised. FIG. 18 is a perspective view showing a state in which the carry-in/out means has advanced toward the cutting device from the state shown in FIG. 17; FIG. 9 is a schematic diagram showing a state in which the back side of the cutting blade held by the blade holding portion is cleaned by the cleaning means shown in FIG. 8 . 9 is a schematic diagram showing a state in which the blade holding portion is cleaned by the cleaning means shown in FIG. 8 .

Below, a preferred embodiment of an automatic exchange device constructed in accordance with the present invention will be described with reference to the drawings.

(Automatic exchange device 2)
Referring to Figure 1, the automatic exchange device, generally designated by the reference numeral 2, comprises at least a cutting blade storage means 4 for storing a plurality of cutting blades, a loading/unloading means 6 for loading and unloading cutting blades from the cutting blade storage means 4, a Y-axis positioning means 8 for positioning the loading/unloading means 6 in an active position and a retracted position in the Y-axis direction relative to the cutting blade storage means 4, a Z-axis moving means 10 for moving the loading/unloading means 6 in the Z-axis direction, an X-axis moving means 12 for moving the loading/unloading means 6 in the X-axis direction to act on cutting blades attached to the spindles of the cutting means of the cutting device, and a cleaning means 13.

The X-axis direction is the direction indicated by arrow X in Figure 1, and the Y-axis direction is the direction indicated by arrow Y in Figure 1, which is perpendicular to the X-axis direction. The Z-axis direction is the direction indicated by arrow Z in Figure 1, which is the up-down direction perpendicular to the X-axis and Y-axis directions. The plane defined by the X-axis and Y-axis directions is substantially horizontal.

(Cutting blade storage means 4)
As shown in Figure 2, the cutting blade storage means 4 includes a drive gear 16 having a rotation axis 14 extending in the Y-axis direction, a driven gear 20 having a rotation axis 18 spaced apart from the drive gear 16 in the Z-axis direction and extending in the Y-axis direction, an endless track 22 wound around the drive gear 16 and the driven gear 20, and a blade support shaft 24 extending in the Y-axis direction, arranged at predetermined intervals on the endless track 22, inserted into a central opening of the cutting blade, and supporting the cutting blade.

(Drive gear 16)
1 and 2, the cutting blade storage means 4 of the illustrated embodiment includes a base plate 26 (see FIG. 1), a support wall 28 extending upward from the upper surface of the base plate 26, and a motor 30 fixed to one surface of the support wall 28. As shown in FIG. 2, the motor 30 is connected to the rotation shaft 14 of the drive gear 16, and the motor 30 rotates the drive gear 16 about its axis in the Y-axis direction.

(Driven gear 20)
2, the driven gear 20 is disposed above the drive gear 16, and the rotation shaft 18 of the driven gear 20 is supported by a support wall 28 so as to be rotatable about the Y-axis direction and movable up and down in the Z-axis direction. The support wall 28 is provided with an elevating means (not shown) for elevating the driven gear 20 in the Z-axis direction. The elevating means may include a ball screw connected to the rotation shaft 18 of the driven gear 20 and extending in the Z-axis direction, and a motor for rotating the ball screw.

(Endless track 22)
The endless track 22 is made up of a number of interconnected link pieces (reference numerals omitted) and is wound around the drive gear 16 and the driven gear 20. The endless track 22 rotates in response to the rotation of the drive gear 16 by the motor 30.

In the cutting blade storage means 4 of the illustrated embodiment, the distance between the drive gear 16 and the driven gear 20 in the Z-axis direction can be adjusted by changing the position of the driven gear 20 in the Z-axis direction using the lifting means. Furthermore, in the cutting blade storage means 4, the length of the endless track 22 can also be adjusted by appropriately increasing or decreasing the number of link pieces on the endless track 22.

(Blade support shaft 24)
2, a plurality of blade support shafts 24 are disposed at predetermined intervals on the endless track 22. As can be understood by referring to FIG. 3 together with FIG. 2, each blade support shaft 24 has a cylindrical base 32 connected to the endless track 22 and a cylindrical shaft 34 extending in the Y-axis direction from the end face of the base 32. The diameter of the shaft 34 is smaller than the diameter of the base 32.

(Hub blade 36)
FIG. 3 also shows a hub blade 36, which serves as a cutting blade stored in the cutting blade storage means 4. The hub blade 36 has an annular base 38 and an annular cutting blade 40 disposed on the outer periphery of the base 38. The base 38 may be formed from an appropriate metal material, such as an aluminum alloy. A circular central opening 38a is provided in the center of the base 38. The cutting blade 40 is formed to a predetermined thickness (e.g., approximately 10 to 30 μm) from abrasive grains such as diamond and a binder such as metal or resin, and protrudes radially outward from the outer periphery of the base 38. Although not shown, an ID (barcode, QR code (registered trademark)) indicating the characteristics of the hub blade 36 is attached to the back side of the base 38.

In the illustrated embodiment, the shaft portion 34 of the blade support shaft 24 has an outer diameter that corresponds to the inner diameter of the central opening 38a of the hub blade 36. In the blade support shaft 24, the shaft portion 34 is inserted into the central opening 38a of the hub blade 36, and multiple (e.g., five) hub blades 36 are supported by the shaft portion 34.

In the illustrated embodiment, as can be seen from Figure 2, hub blades 36 are supported on half of the blade support shafts 24. Furthermore, as shown in Figure 3, a plurality of ball plungers 42 are attached at intervals in the circumferential direction to the tip end of the shaft portion 34 to prevent the hub blades 36 supported by the shaft portion 34 from popping out.

As shown in Figure 4, a flow path 32a is formed inside each base portion 32 of the blade support shaft 24, and multiple flow paths 22a are formed in the endless track 22, communicating with one end of each flow path 32a. The other end of each flow path 32a opens at the end face of the base portion 32 radially outward from the shaft portion 34, as shown in Figure 3.

As shown in FIG. 2, the support wall 28 is provided with an air nozzle 44 that protrudes in the Y-axis direction below the drive gear 16, and the air nozzle 44 is connected to a high-pressure air supply means (not shown). In the illustrated embodiment, the tip of the air nozzle 44 faces the blade support shaft 24 located at the lowest end of the orbit of the blade support shaft 24 that follows the rotation of the endless track 22.

When the hub blade 36 located at the tip of the shaft 34 is removed, high-pressure air is supplied from the air nozzle 44 to the flow path 32a of the base 32 of the lowest blade support shaft 24 via the flow path 22a of the endless track 22, thereby pushing the hub blade 36 remaining on the shaft 34 toward the tip of the shaft 34. However, the action of the ball plunger 42 prevents the hub blade 36 from falling off the shaft 34.

(Carry-in/out means 6)
The loading/unloading means 6 will be described with reference to Figure 5. The loading/unloading means 6 includes at least a Z-rotation shaft 46 extending in the Z-axis direction, a blade holder 48 that is radially connected to the Z-rotation shaft 46 and that suction-holds the cutting blade, and a fixing nut holder 50 that screws a fixing nut onto and unscrews a male thread formed at the tip of the spindle of the cutting device.

As shown in Figure 5, the loading/unloading means 6 in the illustrated embodiment further includes a casing 52, which has a regular hexagonal top plate 54 and six rectangular side walls 56 that hang down from the periphery of the top plate 54. The Z rotation shaft 46 protrudes from the upper surface of the top plate 54. A motor (not shown) connected to the Z rotation shaft 46 is housed inside the casing 52.

In the illustrated embodiment, of the six side walls 56 of the casing 52, blade holders 48 are attached to four side walls 56, and fixing nut holders 50 are attached to two side walls 56, with the two fixing nut holders 50 being provided on a pair of opposing side walls 56.

(Blade holding portion 48)
The blade holding portion 48 is formed in a cylindrical shape, and an end surface 58 of the blade holding portion 48 is provided with a circular central opening 60 capable of receiving the shaft portion 34 of the blade support shaft 24 and the tip of the spindle of the cutting device, and a plurality of suction holes 61 arranged at equal intervals in the circumferential direction around the central opening 60. Each suction hole 61 is connected to suction means (not shown).

When the blade holder 48 is positioned so that its end face 58 contacts the base 38 of the hub blade 36 stored in the cutting blade storage means 4, the suction means generates suction force in the suction hole 61 to suction-hold the hub blade 36.

(Fixing nut holding portion 50)
Continuing the explanation with reference to Figure 5, the fixed nut holding portion 50 includes a cylindrical housing 64 fixed to the side wall 56 of the casing 52, an annular rotating body 66 rotatably accommodated inside the housing 64, and a motor (not shown) that rotates the rotating body 66.

The rotor 66 has a central opening 68 that can receive the tip of the spindle of a cutting device. The end surface 66a of the rotor 66 has multiple suction holes 70 and multiple pins 72 arranged alternately and at intervals around the circumference.

Each suction hole 70 is connected to a suction means (not shown). The pin 72 is positioned by a spring (not shown) built into the rotor 66 at a position where it protrudes from the end face 66a of the rotor 66 (the position shown in Figure 5). When the pin 72 is pushed toward the inside of the rotor 66, the spring contracts and the pin 72 is housed inside the rotor 66. The pin 72 is also positioned to correspond to the position of a pin hole formed in the fixing nut.

In the fixing nut holder 50, the suction means generates suction force in each suction hole 70 to hold the fixing nut by suction, and with the pin 72 inserted into the pin hole formed in the fixing nut, the motor rotates the rotor 66, allowing the fixing nut for securing the hub blade 36 to the spindle of the cutting machine to be screwed and unscrewed from the male thread formed at the tip of the spindle.

Even if the position of the pin 72 of the fixing nut holder 50 is misaligned with the position of the pin hole in the fixing nut when unscrewing (removing) the fixing nut from the spindle, by positioning the end face 66a of the rotor 66 against the end face of the fixing nut attached to the spindle and then storing the pin 72 inside the rotor 66 and then rotating the rotor 66 with the motor, when the position of the pin 72 aligns with the position of the pin hole, the spring will push the pin 72 out and insert it into the pin hole.

In the illustrated embodiment, the loading/unloading means 6, which may be configured as described above, is disposed inside a frame 74, as shown in Figure 1. The frame 74 is supported on a lift table 76 so that it can move freely in the Y-axis direction, and the lift table 76 is supported on a base stand 78 so that it can move up and down freely in the Z-axis direction.

(frame body 74)
1 and 6, the frame 74 includes a rectangular plate-shaped bottom 80, four support posts 82 extending upward from the four corners of the upper surface of the bottom 80, and a plate-shaped ceiling 84 (see FIG. 1) fixed to the upper ends of the support posts 82. A pair of guided members 86, each having a groove 86a extending in the Y-axis direction, are provided on the underside of the bottom 80 at a distance in the X-axis direction.

(Lifting table 76)
The lift table 76 includes a rectangular top plate 88 and four cylindrical legs 90 extending downward from the four corners of the underside of the top plate 88. A pair of guide rails 92 extending in the Y-axis direction and spaced apart in the X-axis direction are provided on the upper surface of the top plate 88. The pair of guide rails 92 are slidably fitted into grooves 86a of a pair of guided members 86 of the frame body 74.

(Y-axis direction positioning means 8)
Furthermore, a Y-axis direction positioning means 8 is provided on the upper surface of the top plate 88 of the lift table 76. The Y-axis direction positioning means 8 has a ball screw 94 extending in the Y-axis direction between a pair of guide rails 92, and a motor 96 that rotates the ball screw 94. A nut portion (not shown) of the ball screw 94 is fixed to the lower surface of the bottom portion 80 of the frame body 74.

In the Y-axis positioning means 8, the ball screw 94 converts the rotational motion of the motor 96 into linear motion and transmits it to the frame 74, moving the frame 74 in the Y-axis direction along a pair of guide rails 92. In this way, the frame 74 on which the loading/unloading means 6 is mounted is slidably supported on the guide rails 92 extending in the Y-axis direction and arranged on the lifting table 76, and can be positioned by the Y-axis positioning means 8 to an operating position and a retracted position in the Y-axis direction relative to the cutting blade storage means 4.

The operating position is a position where the blade holding portion 48 of the loading/unloading means 6 is close to the cutting blade storage means 4, and where the cutting blade supported by the cutting blade storage means 4 can be sucked and held by the blade holding portion 48. The retracted position is a position where the blade holding portion 48 of the loading/unloading means 6 is farther away from the cutting blade storage means 4 than the operating position.

(Base stand 78)
6, the base stand 78 includes a frame 98 and a rectangular base plate 100 fixed to the upper part of the frame 98. Four circular holes 102 are formed in the four corners of the base plate 100, into which the legs 90 of the lift table 76 are slidably inserted. In addition, a female screw 104 is formed in the center of the base plate 100.

(Z-axis moving means 10)
Continuing the explanation with reference to Figure 6, Z-axis movement means 10 is connected to the lift table 76 and the base frame 78. Z-axis movement means 10 includes a ball screw 106 extending in the Z-axis direction, a motor 108 that rotates the ball screw 106, and a connecting plate 110 fixed to the upper end of the motor 108. The ball screw 106 is threadedly engaged with the female thread 104 of the base plate 100. The connecting plate 110 is fixed to the underside of the top plate 88 of the lift table 76 by appropriate connecting means such as bolts (not shown).

In the Z-axis movement means 10, the ball screw 106 converts the rotational motion of the motor 108 into linear motion, and by raising and lowering the lifting table 76 relative to the base frame 78, the frame 74 on which the loading/unloading means 6 is mounted moves in the Z-axis direction.

(X-axis moving means 12)
7, the X-axis moving means 12 includes a bending arm 112 attached to the frame 74, and a first motor 114 and a second motor 115 that operate the bending arm 112. The bending arm 112 has a first arm piece 118 swingably connected to the underside of the ceiling portion 84 of the frame 74 via a spacer 116, and a second arm piece 120 swingably connected to the underside of the first arm piece 118.

The spacer 116 is disposed at one end of the first arm piece 118. The first arm piece 118 is connected to the ceiling portion 84 with the spacer 116 side serving as the swing center. A spacer 122 is also provided on the upper surface of the other end of the first arm piece 118. The second arm piece 120 is connected to the first arm piece 118 with the spacer 122 side serving as the swing center.

A circular hole (not shown) is provided at the tip of the second arm piece 120 (the end opposite the spacer 122). The Z rotation shaft 46 of the loading/unloading means 6 is inserted into this circular hole, and the Z rotation shaft 46 is fixed to the second arm piece 120 so that it cannot rotate. When the motor of the loading/unloading means 6, which is connected to the Z rotation shaft 46, is driven, the casing 52 of the loading/unloading means 6 rotates relative to the second arm piece 120, and the blade holder 48 and fixing nut holder 50 can be positioned in any orientation. In this way, the loading/unloading means 6 is connected to the tip of the bending arm 112 via the Z rotation shaft 46, and is disposed on the frame body 74 via the bending arm 112.

In the X-axis movement means 12, the first motor 114 swings the first arm piece 118 around the spacer 116 side as the swing center, and the second motor 115 swings the second arm piece 120 around the spacer 122 side as the swing center, thereby bending or extending the bending arm 112 and moving the loading/unloading means 6 in the X-axis direction.

(Cleaning means 13)
The cleaning means 13 has a blade holder cleaning unit that cleans the blade holder 48, and a cutting blade cleaning unit that cleans the back side of the cutting blade held by the blade holder 48. In the illustrated embodiment, as shown in Figures 1 and 8, the blade holder cleaning unit and the cutting blade cleaning unit are configured from a single common member.

Referring to Figure 8, the cleaning means 13 includes a circular base plate 124 mounted at the center of the drive gear 16 and a stepped cylindrical cleaning member 126 fixed to one side of the base plate 124. The cleaning member 126 may be made of felt or a hard sponge made of synthetic resin.

The cleaning member 126 has a large diameter portion 128 on the substrate 124 side and a small diameter portion 130 with a smaller diameter than the large diameter portion 128. The large diameter portion 128 is sized to be able to clean the end surface 58 of the blade holding portion 48 and the back side of the hub blade 36. The small diameter portion 130 is sized to be able to clean the central opening 38a of the hub blade 36 and the inside of the central opening 60 of the blade holding portion 48.

Although not shown, a cleaning liquid flow path may be formed that passes through the drive gear 16, the rotation shaft 14 of the drive gear 16, and the motor 30 that rotates the drive gear 16, and reaches the cleaning member 126, and cleaning liquid is supplied to the cleaning member 126 through this cleaning liquid flow path. It is preferable that the cleaning liquid flow path branches radially in the radial direction of the cleaning member 126 inside the cleaning member 126. This allows cleaning liquid to be supplied evenly throughout the entire cleaning member 126.

As described above, in the illustrated embodiment, the cleaning means 13 has the blade holder cleaning unit and cutting blade cleaning unit configured as a single common member, but the blade holder cleaning unit and cutting blade cleaning unit may also be provided separately. In this case, one of the blade holder cleaning unit or cutting blade cleaning unit may be attached to the drive gear 16, and the other of the blade holder cleaning unit or cutting blade cleaning unit may be attached to the driven gear 20. Alternatively, the cleaning means 13 may be attached to an appropriate bracket (not shown).

Next, with reference to Figures 9 to 13, we will explain the cutting device 170 to which the automatic exchange device 2 described above is connected.

(Cutting device 170)
As shown in FIG. 9 , the cutting device 170 includes a chuck table 172 having a holding surface for holding a workpiece, cutting means 174 having a cutting blade attached with a fixing nut for cutting the workpiece held on the chuck table 172, X-axis feed means 176 for feeding the chuck table 172 for processing in the X-axis direction, Y-axis feed means 178 for indexing and feeding the cutting means 174 in the Y-axis direction perpendicular to the X-axis direction, and Z-axis feed means 180 for feeding the cutting means 174 in the Z-axis direction perpendicular to the X-axis and Y-axis directions.

(Chuck table 172)
9 and 10 , the cutting device 170 includes an X-axis movable plate 184 that is provided on the upper surface of a base 182 (see FIG. 9 ) so as to be movable in the X-axis direction, a support column 186 fixed to the upper surface of the X-axis movable plate 184, and a cover plate 188 fixed to the upper end of the support column 186. A circular opening 188a is formed in the cover plate 188. The chuck table 172 is rotatably mounted on the upper end of the support column 186 and extends upward through the circular opening 188a in the cover plate 188. The chuck table 172 is rotated about the Z-axis by a motor (not shown) built into the support column 186.

As shown in Figure 10, a porous, circular suction chuck 190 connected to a suction means (not shown) is located at the upper end of the chuck table 172. The suction means generates a suction force on the upper surface of the suction chuck 190 on the chuck table 172, thereby suction-holding a workpiece placed on the upper surface of the suction chuck 190.

In this way, on the chuck table 172, the upper surface of the suction chuck 190 serves as the holding surface for holding the workpiece, and the holding surface is positioned on the XY plane defined by the X-axis and Y-axis directions. Furthermore, multiple clamps 192 are arranged around the periphery of the chuck table 172 at intervals in the circumferential direction.

(X-axis feed means 176)
10 , the X-axis feed means 176 has a ball screw 198 that is connected to the X-axis movable plate 184 and extends in the X-axis direction, and a motor 200 that rotates the ball screw 198. The X-axis feed means 176 converts the rotational motion of the motor 200 into linear motion using the ball screw 198 and transmits it to the X-axis movable plate 184, moving the X-axis movable plate 184 along the guide rails 182 a of the base 182 and feeding the chuck table 172 for processing in the X-axis direction.

As shown in FIG. 9, the cutting device 170 includes a gate-shaped frame 202 positioned across the chuck table 172. The frame 202 has a pair of support columns 204 spaced apart in the Y-axis direction and extending upward from the top surface of the base 182, and a beam 206 spanning between the upper ends of the pair of support columns 204 and extending in the Y-axis direction.

(Cutting means 174)
A pair of cutting means 174 are provided on one side surface of the beam 206 (the side surface on the rear side in FIG. 9 ) at a distance in the Y-axis direction. In the cutting device 170 of the illustrated embodiment, a pair of cutting means 174 is provided so that the cutting blades face each other, and a workpiece held on the chuck table 172 can be simultaneously cut by the pair of cutting blades. Note that the number of cutting means 174 may be one.

As shown in Figure 11, each cutting means 174 comprises a rectangular Y-axis movable member 208 supported on one side of a beam 206 so as to be movable in the Y-axis direction, a Z-axis movable member 210 with an L-shaped cross section supported on the Y-axis movable member 208 so as to be movable up and down in the Z-axis direction, and a spindle housing 212 fixed to the lower end of the Z-axis movable member 210.

A pair of guided grooves 208a extending in the Y-axis direction and spaced apart in the Z-axis direction are formed on one side of the Y-axis movable member 208 (the side facing the viewer in Figure 11). The guided grooves 208a are slidably connected to a pair of guide rails (not shown) extending in the Y-axis direction and spaced apart in the vertical direction on one side of the beam 206.

(Y-axis feed means 178)
Y-axis feed means 178 has a ball screw 214 extending in the Y-axis direction on one side surface of beam 206, and a motor 216 that rotates ball screw 214. Ball screw 214 is connected to Y-axis movable member 208. Y-axis feed means 178 converts the rotational motion of motor 216 into linear motion using ball screw 214 and transmits it to Y-axis movable member 208, and indexes and feeds Y-axis movable member 208 in the Y-axis direction along a guide rail attached to one side surface of beam 206.

A pair of guide rails (not shown) extending in the Z-axis direction and spaced apart in the Y-axis direction are formed on the other side of the Y-axis movable member 208 (the side facing the rear in Figure 11), and the Z-axis movable member 210 has a pair of guided grooves (not shown) that are slidably connected to the pair of guide rails of the Y-axis movable member 208.

(Z-axis feeding means 180)
Z-axis feed means 180 has a ball screw (not shown) that is connected to Z-axis movable member 210 and extends in the Z-axis direction, and a motor 218 that rotates this ball screw. Z-axis feed means 180 converts the rotational motion of motor 218 into linear motion using the ball screw and transmits it to Z-axis movable member 210, and feeds Z-axis movable member 210 in the Z-axis direction along the guide rail of Y-axis movable member 208.

Referring to Figure 12, the spindle housing 212 supports a cylindrical spindle 220 that can rotate freely around the Y-axis direction, and houses a motor (not shown) that rotates the spindle 220. A cutting blade that cuts the workpiece is removably fixed to the tip of the spindle 220 by a fixing nut 222.

A blade cover 224 that covers the cutting blade is attached to the tip of the spindle housing 212. The blade cover 224 has a first cover member 224a fixed to the tip of the spindle housing 212 and a second cover member 224b movably attached to the tip of the first cover member 224a. The second cover member 224b is designed to be moved in the X-axis direction by an appropriate actuator (not shown), such as an air cylinder. When replacing the cutting blade, it is positioned in the open position shown in Figure 12, and when cutting, it is positioned in the closed position shown in Figure 11.

As shown in Figure 13, an annular mount flange 226 that protrudes radially outward is provided on the outer peripheral surface of the tip end of the spindle 220. An annular recess 226a is formed in the radially inner portion of the tip end surface of the mount flange 226, and the outer peripheral portion of the tip end surface of the mount flange 226 forms an annular receiving portion 226b that protrudes in the axial direction. In addition, a male thread 228 is formed on the outer peripheral surface of the spindle 220 further tip side than the mount flange 226.

The central opening 38a of the hub blade 36 fits into the tip of the spindle 220, and the external threads 228 of the spindle 220 are screwed (fastened) into the fixing nut 222, thereby sandwiching the hub blade 36 between the receiving portion 226b of the mount flange 226 and the fixing nut 222 and removably fixing it to the tip of the spindle 220. Furthermore, the side of the fixing nut 222 has multiple pin holes 222a formed at equal intervals around the circumference, into which pins 72 of the fixing nut holder 50 of the loading/unloading means 6 are inserted.

As shown in Figure 9, a pair of imaging means 230 for capturing images of the workpiece held on the chuck table 172 is mounted on the other side of the beam 206 of the frame 202 (the side facing the front in Figure 9) so as to be movable in the Y-axis direction, and a pair of moving means 232 for moving the imaging means 230 in the Y-axis direction is also mounted.

The moving means 232 has a ball screw 234 extending in the Y-axis direction on the other side of the beam 206, and a motor 236 that rotates the ball screw 234. The ball screw 234 is connected to the imaging means 230. The moving means 232 converts the rotational motion of the motor 236 into linear motion and transmits it to the imaging means 230, moving the imaging means 230 in the Y-axis direction along a guide rail 206a attached to the other side of the beam 206. Note that there may be only one imaging means 230.

(cutting)
When cutting a workpiece such as a wafer using the cutting device 170, the workpiece is first sucked onto the chuck table 172. Next, the X-axis feed means 176 moves the chuck table 172 below the imaging means 230, and the moving means 232 adjusts the position of the imaging means 230 in the Y-axis direction. Next, the imaging means 230 images the workpiece from above, and the cutting area of the workpiece is detected.

Next, based on the cutting area of the workpiece detected by the imaging means 230, the chuck table 172 is rotated to adjust the orientation of the cutting area of the workpiece relative to the cutting blades of the cutting means 174. Next, the X-axis feed means 176 moves the chuck table 172 in the X-axis direction, and the Y-axis feed means 178 moves the spindle housing 212 in the Y-axis direction, positioning the pair of cutting blades above the cutting area of the workpiece.

Then, the spindle housing 212 is lowered by the Z-axis feed means 180, and the cutting edge of the rapidly rotating cutting blade is caused to cut into the cutting area of the workpiece. While supplying cutting water to the area where the cutting blade will cut, the chuck table 172 is fed in the X-axis direction to perform the specified cutting process on the cutting area of the workpiece. The spindle housing 212 is indexed and fed in the Y-axis direction by the Y-axis feed means 178, and the above cutting process is repeated as appropriate until the entire cutting area of the workpiece is cut. After the cutting process is complete, the machined workpiece is transported to the next process.

(Cutting blade replacement)
When the cutting process is repeatedly performed, the cutting blade wears, and when the wear of the cutting blade reaches a predetermined amount, cutting accuracy cannot be maintained, so it is necessary to replace the cutting blade attached to the spindle 220 with a new cutting blade. Also, even if the wear of the cutting blade attached to the spindle 220 has not reached the predetermined amount, when cutting a workpiece made of a material different from that of the workpiece previously cut, it may be necessary to replace the cutting blade with one that suits the material of the workpiece.

In the illustrated embodiment, as shown in FIG. 14, an automatic blade changer 2 that can automatically change the cutting blade of the cutting device 170 is connected to the cutting device 170, and a method for changing the hub blade 36 using the automatic blade changer 2 will be described below.

As shown in Figure 14, the automatic changer 2 is located at the rear of the cutting device 170 in the X-axis direction, so that it can be attached to a cutting device 170 that has already been delivered to a user. When using the automatic changer 2 to replace a cutting blade attached to the cutting device 170, first rotate the endless track 22 of the cutting blade storage means 4 and position the blade support shaft 24 supporting the new hub blade 36 to be loaded into the cutting device 170 at a predetermined position (for example, the lowest position on the track of the blade support shaft 24).

Next, as shown in Figure 15, the casing 52 is rotated by a motor connected to the Z rotation shaft 46 of the loading/unloading means 6, and the side wall 56 of the casing 52 to which the blade holder 48 is attached is aligned in the X-axis direction, so that the blade holder 48 faces the cutting blade storage means 4.

The X-axis moving means 12 and Z-axis moving means 10 are then operated to adjust the X-axis and Z-axis positions of the blade holding portion 48 so that the shaft portion 34 of the blade support shaft 24 in the predetermined position can be inserted into the central opening 60 of the blade holding portion 48 (see Figure 5).

Next, as shown in Figure 16, the frame 74 is moved in the Y-axis direction by the Y-axis positioning means 8, and the loading/unloading means 6 is positioned at an operating position where the hub blade 36 supported by the blade support shaft 24 can be held by the blade holder 48. This inserts the shaft 34 of the blade support shaft 24 in the predetermined position into the central opening 60 of the blade holder 48, and brings the end face 58 of the blade holder 48 into contact with the end face of the hub blade 36 located at the tip of the shaft 34. Next, suction force is generated in the suction hole 61 of the blade holder 48, and the hub blade 36 located at the tip of the shaft 34 is suction-held by the blade holder 48.

Next, the Y-axis positioning means 8 is activated, and the loading/unloading means 6 is moved away from the cutting blade storage means 4 in the Y-axis direction to a retracted position. Next, the casing 52 of the loading/unloading means 6 is rotated 180 degrees, so that the blade holding portion 48 opposite the blade holding portion 48 that holds the hub blade 36 by suction faces the cutting blade storage means 4.

The Y-axis positioning means 8 is then activated, positioning the loading/unloading means 6 at an operating position where the opposite blade holder 48 can hold the hub blade 36 of the blade support shaft 24. Next, suction force is generated in the suction hole 61 of the opposite blade holder 48, causing the blade holder 48 to suction-hold the hub blade 36 located at the tip of the shaft 34. This results in a state in which a new hub blade 36 is suction-held by a pair of opposing blade holders 48 out of the four blade holders 48.

Next, as shown in FIG. 17, the frame 74 is moved in the Y-axis direction by the Y-axis positioning means 8, and the lifting table 76 is moved in the Z-axis direction by the Z-axis moving means 10. This separates the loading/unloading means 6 from the cutting blade storage means 4 and positions it in a retracted position, and also adjusts the Y-axis and Z-axis positions of the loading/unloading means 6 relative to the cutting device 170. After the position adjustment, the Y-axis position of the loading/unloading means 6 is between the pair of cutting means 174 of the cutting device 170, and the Z-axis position of the loading/unloading means 6 after the position adjustment is above the holding surface of the chuck table 172.

Next, as shown in Figure 18, the X-axis movement means 12 moves the loading/unloading means 6 in the X-axis direction, and the X-axis position of the loading/unloading means 6 relative to the pair of cutting means 174 is adjusted. Specifically, the X-axis position of the center of the new pair of hub blades 36 held by suction by the pair of blade holding portions 48 of the loading/unloading means 6 is aligned with the X-axis position of the center of the pair of hub blades 36 attached to the pair of cutting means 174.

The Z-axis movement means 10 of the automatic exchanger 2 or the Z-axis feed means 180 of the cutting device 170 is also operated to align the Z-axis position of the center of the hub blade 36 of the blade holder 48 with the Z-axis position of the center of the hub blade 36 of the cutting means 174.

Next, the casing 52 of the loading/unloading means 6 is rotated 60° so that the pair of fixing nut holders 50 face the hub blades 36 of the pair of cutting means 174. The casing 52 may also be rotated 60° before the loading/unloading means 6 is advanced.

Next, the second cover member 224b of each blade cover 224 of the pair of cutting means 174 is positioned in the open position (see Figure 12). Next, the cutting means 174 is moved in the Y-axis direction by the Y-axis feed means 178 of the cutting device 170, and the fixing nut 222 securing the hub blade 36 to the spindle 220 is brought into contact with the end face 66a of the rotating body 66 of the fixing nut holder 50. As a result, the pin 72 of the fixing nut holder 50 is pushed by the fixing nut 222 and accommodated inside the rotating body 66, and the tip of the spindle 220 is accommodated in the central opening 68 of the rotating body 66.

Next, when the motor of the fixing nut holder 50 rotates the rotor 66, the pins 72 fit into the pin holes 222a of the fixing nut 222 when they align with the pin holes 222a. The rotational motion of the rotor 66 is transmitted to the fixing nut 222 via the pins 72, loosening the fixing nut 222. This allows the fixing nut 222 to be unscrewed (removed) from the male thread 228 of the spindle 220 of the cutting means 174. Suction force is also generated in the suction holes 70 of the fixing nut holder 50, and the removed fixing nut 222 is held by suction by the fixing nut holder 50.

Next, the cutting means 174 is moved away from the loading/unloading means 6 by the Y-axis feed means 178, and the casing 52 of the loading/unloading means 6 is rotated 60° so that the empty blade holding section 48 that is not holding the hub blade 36 by suction faces the hub blade 36 of the cutting means 174.

The cutting means 174 is then moved closer to the loading/unloading means 6 by the Y-axis feed means 178, and the spindle 220 of the cutting means 174 is inserted into the central opening 60 of the blade holder 48, while the end face of the hub blade 36 of the cutting means 174 is brought into contact with the end face 58 of the empty blade holder 48. Next, suction force is generated in the suction hole 61 of the blade holder 48, and the hub blade 36 of the cutting means 174 is suction-held by the blade holder 48.

Next, the cutting means 174 is moved away from the loading/unloading means 6 by the Y-axis feed means 178, and the casing 52 of the loading/unloading means 6 is rotated 60° so that the blade holding portion 48, which is holding the new hub blade 36 by suction, faces the spindle 220 of the cutting means 174.

Then, the cutting means 174 is moved closer to the loading/unloading means 6 by the Y-axis feed means 178, and the spindle 220 is inserted into the central opening 38a of the new hub blade 36, bringing the end face of the hub blade 36 into contact with the receiving portion 226b of the mounting flange 226 of the spindle 220. Next, the suction force of the blade holder 48 is released, and the new hub blade 36 is transferred from the blade holder 48 to the spindle 220.

Next, the cutting means 174 is moved away from the loading/unloading means 6 by the Y-axis feed means 178, and the casing 52 of the loading/unloading means 6 is rotated 60° so that the fixing nut holding portion 50, which is holding the removed fixing nut 222 by suction, faces the spindle 220 of the cutting means 174.

Then, the cutting means 174 is moved closer to the loading/unloading means 6 by the Y-axis feed means 178, and the fixing nut 222 held by suction by the fixing nut holding unit 50 is fitted onto the tip of the spindle 220. Next, the motor of the fixing nut holding unit 50 is operated in the opposite direction to when the fixing nut 222 was removed, rotating the fixing nut 222 and screwing (fastening) the fixing nut 222 onto the male thread 228 of the spindle 220.

This allows the new hub blade 36 to be attached to the cutting means 174 to be clamped between the receiving portion 226b of the mounting flange 226 of the spindle 220 and the fixing nut 222, and fixed to the spindle 220.

Next, after releasing the suction force of the fixing nut holder 50, the second cover member 224b of the blade cover 224 of the cutting means 174 is positioned in the closed position. Note that the removal and installation of the fixing nut 222 and hub blade 36 as described above may be performed simultaneously for the pair of cutting means 174, or may be performed separately.

Next, the loading/unloading means 6 is retracted and the casing 52 of the loading/unloading means 6 is rotated 60° so that one of the pair of removed hub blades 36 faces the cutting blade storage means 4. The pair of hub blades 36 removed from the cutting device 170 are then fitted onto the blade support shaft 24 of the cutting blade storage means 4 for storage. In the illustrated embodiment of the automatic blade changer 2, the back side of the hub blade 36 can be cleaned with the cleaning member 126 of the cleaning means 13 before the removed hub blade 36 is fitted onto the blade support shaft 24, as will be described with reference to Figure 19.

Note that in Figure 19, for convenience, the blade holder 48 and the hub blade 36 are shown separated, but in reality, the hub blade 36 is cleaned while being held by suction by the blade holder 48.

When cleaning the back side of the hub blade 36, the X-axis movement means 12 and Z-axis movement means 10 are operated to adjust the X-axis and Z-axis positions of the blade holding portion 48 so that the central opening 38a of the hub blade 36, which is held by suction by the blade holding portion 48, can fit into the small diameter portion 130 of the cleaning member 126.

The cleaning means 13 is then rotated in the direction indicated by arrow R together with the drive gear 16. The Y-axis positioning means 8 then moves the loading/unloading means 6 in the Y-axis direction, pressing the back side of the hub blade 36 held by suction in the blade holding portion 48 against the large diameter portion 128 of the cleaning member 126, and fitting the central opening 38a of the hub blade 36 into the small diameter portion 130 of the cleaning member 126. This allows the back side and central opening 38a of the hub blade 36 to be cleaned by the cleaning member 126 of the cleaning means 13.

When cleaning, it is preferable to supply cleaning liquid to the cleaning member 126 via the cleaning liquid flow path. This can further improve the cleanliness of the hub blade 36.

If the blade holder 48 is rotatably attached to the casing 52, the blade holder 48, which holds the hub blade 36 by suction, may be rotated when pressing the hub blade 36 against the cleaning member 126.

Furthermore, as shown in Figure 20, the end surface of the blade holding portion 48 can also be cleaned by pressing the blade holding portion 48 against the cleaning member 126 when the hub blade 36 is not being held by suction with the blade holding portion 48. When cleaning the blade holding portion 48, cleaning liquid may also be supplied to the cleaning member 126.

After cleaning one back side of the removed hub blade 36, rotate the endless track 22 of the cutting blade storage means 4 and position the empty blade support shaft 24 that is not supporting the hub blade 36 in a predetermined position (for example, the lowest position in the track of the blade support shaft 24).

Next, the X-axis moving means 12 and Z-axis moving means 10 are operated to adjust the X-axis and Z-axis positions of the blade holding portion 48 so that the shaft portion 34 of the blade support shaft 24 in the specified position can be inserted into the central opening 38a of one of the hub blades 36 held by suction by the blade holding portion 48.

Then, the frame 74 is moved in the Y-axis direction by the Y-axis positioning means 8, and the shaft portion 34 of the blade support shaft 24 in the predetermined position is inserted into the central opening 38a of one of the hub blades 36 held by suction by the blade holding portion 48, and the end face of one of the hub blades 36 is brought into contact with the end face of the base portion 32 of the blade support shaft 24. Next, the suction force of the blade holding portion 48 is released, and one of the removed pair of hub blades 36 is transferred to the blade support shaft 24.

The Y-axis positioning means 8 also moves the loading/unloading means 6 away from the cutting blade storage means 4, and the casing 52 of the loading/unloading means 6 is rotated 180 degrees so that the opposite blade holding portion 48, which holds the other of the pair of removed hub blades 36 by suction, faces the cutting blade storage means 4.

The other of the removed hub blades 36 is then cleaned in the same manner as above, and the frame 74 is then moved in the Y-axis direction by the Y-axis positioning means 8, and the shaft portion 34 of the blade support shaft 24 in the specified position is inserted into the central opening 38a of the other hub blade 36 held by suction by the blade holder 48 on the opposite side, and the end face of the other hub blade 36 is brought into contact with the end face of the hub blade 36 supported by the blade support shaft 24. Next, the suction force of the blade holder 48 is released, and the other of the pair of removed hub blades 36 is transferred to the blade support shaft 24.

In this way, the automatic blade changer 2 of the illustrated embodiment can be attached to a cutting device 170 that has already been delivered to a user, allowing the cutting blade attached to the cutting means 174 of the cutting device 170 to be replaced. In addition, the back side of the cutting blade and the blade holder 48 can be cleaned using the cleaning means 13. Therefore, even if the cutting blade is repeatedly replaced, the automatic blade changer 2 can reliably hold the cutting blade using the blade holder 48, and the ID of the cutting blade can be kept readable.

2: Automatic exchange device 4: Cutting blade storage means 6: Carrying-in/out means 8: Y-axis direction positioning means 10: Z-axis movement means 12: X-axis movement means 13: Cleaning means 14: Rotating shaft 16: Driving gear 18: Rotating shaft 20: Driven gear 22: Caterpillar track 24: Blade support shaft 36: Hub blade (cutting blade)
38: Base 38a: Central opening 40: Cutting blade 46: Z rotation axis 48: Blade holding portion 50: Fixing nut holding portion 74: Frame 76: Lifting table 92: Guide rail 112: Bent arm 170: Cutting device 172: Chuck table 174: Cutting means 176: X-axis feed means 178: Y-axis feed means 180: Z-axis feed means 220: Spindle 222: Fixing nut 228: Male thread (spindle)

Claims (6)

an automatic changer comprising: a chuck table having a holding surface for holding a workpiece; cutting means having a cutting blade attached with a fixing nut for cutting the workpiece held on the chuck table; X-axis feed means for feeding the chuck table in an X-axis direction for processing; Y-axis feed means for indexing and feeding the cutting means in a Y-axis direction perpendicular to the X-axis direction; and Z-axis feed means for cutting and feeding the cutting means in a Z-axis direction perpendicular to the X-axis and Y-axis directions, wherein the holding surface is connected to a cutting device defined in the X-axis and Y-axis directions;
The cutting blade storage device includes at least a cutting blade storage means for storing a plurality of cutting blades, a carrying-in/out means for carrying cutting blades in and out of the cutting blade storage means, a Y-axis positioning means for positioning the carrying-in/out means at an operating position and a retracted position in the Y-axis direction relative to the cutting blade storage means, a Z-axis moving means for moving the carrying-in/out means in the Z-axis direction, an X-axis moving means for moving the carrying-in/out means in the X-axis direction to act on the cutting blades attached to the spindles of the cutting means, and a cleaning means.
The carry-in/out means includes a Z rotation shaft extending in the Z axis direction, a blade holding portion radially connected to the Z rotation shaft and suction-holding the cutting blade, and a fixing nut holding portion that screws the fixing nut onto and unscrews the male screw formed at the tip of the spindle,
The cleaning means is an automatic changer having a blade holder cleaning unit that cleans the blade holder, and a cutting blade cleaning unit that cleans the back side of the cutting blade held by the blade holder. The automatic blade changer according to claim 1, wherein the carrying-in/out means is mounted on a frame via a bent arm, the frame is slidably supported on a guide rail extending in the Y-axis direction and mounted on a lifting table, and the Y-axis positioning means positions the cutting blade storage means at the operating position and the retracted position in the Y-axis direction. The automatic exchange device according to claim 2, wherein the bending arm moves the loading/unloading means forward and backward in the X-axis direction. The automatic blade changer according to claim 1, wherein the cutting blade storage means includes a drive gear having a rotational axis extending in the Y-axis direction, a driven gear spaced apart from the drive gear in the Z-axis direction and having a rotational axis extending in the Y-axis direction, an endless track wound around the drive gear and the driven gear, and blade support shafts extending in the Y-axis direction, arranged at predetermined intervals on the endless track, inserted into central openings in the cutting blades, and supporting the cutting blades. An automatic gear changer as described in claim 4, in which the distance between the drive gear and the driven gear in the Z-axis direction can be adjusted and the length of the endless track can also be adjusted. The cutting blades stored in the cutting blade storage means are hub blades having cutting edges disposed on the outer periphery of a base,
5. The automatic blade changer according to claim 4, wherein said blade support shaft has an outer diameter corresponding to an inner diameter of a central opening of said hub blade, and said blade holder holds said hub blade.