Tool changing device

Abstract

This invention provides a tool changing device that prevents breakage of cutting tools and damage to the flange when mounting cutting tools with different cutting thicknesses on a tool mounting base. The tool changing device used in a cutting apparatus includes: a holding part that detachably holds one side of the cutting tool; a moving part that moves the holding part, holding the cutting tool, relative to the spindle in the axial direction of the spindle, positioning the holding part at least at a mounting position where the other side of the cutting tool, located opposite to one side, is at least a predetermined distance from the flange of the tool mounting base, and at a disengaged position where the cutting tool is away from the tool mounting base; and a thickness information acquiring part that acquires information about the thickness of the cutting tool, adjusting the mounting position of the holding part based on the thickness of the cutting tool acquired by the thickness information acquiring part.

Description

Technical Field

[0001] This invention relates to a tool changing device used in a cutting apparatus. Background Technology

[0002] To cleave a semiconductor wafer, such as silicon, with multiple devices formed on its front side into individual device chips, a cutting device with a ring-shaped cutting tool is used. This cutting tool is a consumable and needs to be replaced as needed depending on the degree of wear.

[0003] For example, when the operator changes the cutting tool manually, after removing the used cutting tool from the tool mount fixed to the front end of the spindle, a new cutting tool is installed in the tool mount.

[0004] During installation, first, insert the boss of the tool mount into the through hole of the cutting tool. Next, with the cutting tool abutting against the flange of the tool mount, insert the boss into the press nut and tighten the press nut into the threaded groove on the outer peripheral side of the boss.

[0005] Thus, the cutting tool is held by the flange and the pressing nut, fixing the spindle's axial position. However, because the cutting edge of the cutting tool is very thin and easily damaged, a skilled operator is required for tool changeover.

[0006] Therefore, a tool changing device has been developed that automatically removes a new cutting tool from a cutting tool stand and installs it into a tool mounting base (for example, see Patent Document 1). The cutting tool that is replaced by the tool changing device is usually a hub-type cutting tool (i.e., a hub tool) having a metal annular base and an annular cutting edge fixed to the outer periphery of the annular base.

[0007] When using a tool changing device to mount a hub tool on a tool mounting base, for example, the tool holding unit of the tool changing device moves the hub tool while holding the front side of the annular base, so that the boss is inserted into the through hole of the annular base in such a way that the back side of the annular base abuts against the flange.

[0008] The annular base of the hub tool is uniform in thickness, regardless of the type of cutting edge. Therefore, when the hub tool is mounted on the tool holder using a tool changing device, it is usually moved to a predetermined position where it abuts against the flange on the back side of the annular base, regardless of the cutting edge thickness.

[0009] However, there are also tool changing devices that replace washer-type cutting tools (i.e., hubless tools) that do not have an annular base but are formed by the cutting edge itself (for example, see Patent Document 2). The tool changing device has a fixture for attracting and holding the hubless tool.

[0010] When using this tool changing device to mount a hubless tool onto a tool mounting base, firstly, a jig is used to attract and hold the front side of the hubless tool. Then, the jig is moved until the back side of the hubless tool contacts the flange. However, the cutting thickness of the hubless tool varies, for example, from 0.02 mm to 3.0 mm.

[0011] Therefore, for example, after installing a hubless tool with a relatively thin cutting edge on the tool holder, instead of installing a hubless tool with a relatively thick cutting edge, the hubless tool with a relatively thick cutting edge will be excessively pressed against the flange. In this case, it may cause the hubless tool to break or the flange to be damaged.

[0012] Patent Document 1: Japanese Patent Application Publication No. 2007-98536

[0013] Patent Document 2: Japanese Patent Application Publication No. 2016-64450 Summary of the Invention

[0014] The present invention was made in view of the above-mentioned problems, and prevents the cutting tools from breaking and the flange from being damaged when cutting tools with different cutting thicknesses are mounted on the tool mounting base.

[0015] According to one aspect of the present invention, a tool changing device is provided for use in a cutting device that cuts a workpiece using an annular cutting tool mounted on the front end of a spindle via a tool mounting seat. The tool mounting seat has: a cylindrical boss portion that, when fixed to the front end of the spindle, protrudes along the axial direction of the spindle and is inserted into a through hole of the cutting tool; and an annular flange portion located at the base end side of the boss portion, protruding radially outward from the boss portion. The flange portion is capable of contacting the cutting tool when the cutting tool is inserted into the boss portion. The device includes: a holding part that detachably holds one side of the cutting tool; a moving part that moves the holding part, which holds the cutting tool, relative to the spindle in the axial direction of the spindle, positioning the holding part at least at a mounting position where the other side of the cutting tool located on the opposite side is at a predetermined distance from the flange of the tool mount and at a disengaged position where the cutting tool is away from the tool mount; and a thickness information acquisition part that acquires information about the thickness of the cutting tool, and the mounting position of the holding part is adjusted based on the thickness of the cutting tool acquired by the thickness information acquisition part.

[0016] Preferably, the thickness information acquisition unit includes a camera unit, a reader, or a measurement unit. The camera unit is used to acquire an image of the identification information disposed on the cutting tool or in a storage box for storing the cutting tool. The reader is used to read the identification information. The measurement unit measures the thickness of the cutting tool.

[0017] Alternatively, preferably, an annular pressing flange is installed on the tool mounting base to clamp the cutting tool together with the flange portion. The pressing flange has: a central hole that is inserted into the boss portion; and a through hole that is provided outside the central hole and extends from one side of the pressing flange to the other side of the pressing flange. The retaining portion attracts and retains the opening exposed on one side of the pressing flange in the through hole, thereby attracting and retaining the cutting tool via the other side of the pressing flange.

[0018] Alternatively, preferably, the cutting tool has: an annular base portion held by the retaining portion; and an annular grinding portion fixed to the outer periphery of the base portion, wherein the retaining portion attracts and retains one side of the base portion, thereby attracting and retaining the cutting tool.

[0019] One aspect of the tool changing device of the present invention includes: a holding part that detachably holds one side of a cutting tool; a moving part that moves the holding part, which holds the cutting tool, relative to the spindle in the axial direction of the spindle, positioning the holding part at least in an installed position and a dismounted position; and a thickness information acquisition part that acquires information about the thickness of the cutting tool.

[0020] The mounting position of the retainer is adjusted according to the thickness of the cutting tool obtained by the thickness information acquisition unit. Therefore, even when cutting tools with different cutting thicknesses are mounted on the tool mount, damage to the cutting tool and the flange portion can be prevented. Attached Figure Description

[0021] Figure 1 This is a perspective view of the cutting device according to the first embodiment.

[0022] Figure 2 This is an exploded 3D view of the cutting unit.

[0023] Figure 3 This is a partial cross-sectional side view of the cutting unit.

[0024] Figure 4 This is a 3D view of the tool changing unit.

[0025] Figure 5 This is a side view of the replacement mechanism.

[0026] Figure 6This is a three-dimensional view of the tool storage area.

[0027] Figure 7 Figure (A) shows the installation of a cutting tool with a first thickness. Figure 7 (B) is a diagram showing the installation of a cutting tool with a second thickness.

[0028] Figure 8 (A) is Figure 7 A magnified view of (A). Figure 8 (B) is Figure 7 A magnified view of (B).

[0029] Figure 9 (A) is a diagram showing the situation where image recognition information is obtained. Figure 9 (B) is a diagram showing the situation where the thickness of the cutting edge is obtained.

[0030] Figure 10 This is an exploded perspective view of the cutting unit in the second embodiment.

[0031] Figure 11 This is a partial cross-sectional side view of the cutting unit in the second embodiment.

[0032] Figure 12 This is an exploded perspective view of the cutting unit in the third embodiment.

[0033] Figure 13 This is a partial cross-sectional side view of the cutting unit in the third embodiment.

[0034] Figure 14 This is an exploded perspective view of the cutting unit in the fourth embodiment.

[0035] Figure 15 This is a partial cross-sectional side view of the cutting unit in the fourth embodiment.

[0036] Label Explanation

[0037] 2: Cutting device; 4: Base; 4a, 4b: Opening; 6: Lift; 6a: Lifting platform; 8: Box; 8a: Support plate; 10: Cleaning unit; 11: Workpiece; 12: Rotary table; 13: Cutting belt; 14: Guide rail; 15: Frame; 16: Table cover; 17: Workpiece unit; 18: Dustproof and drip-proof cover; 20: Chuck table; 20a: Fixture unit; 22: Dressing table; 24: Cover component; 26, 100, 112, 120: Cutting unit; 28: Spindle housing; 30: Spindle; 30a: Front end; 30b: Axial direction; 30c: Threaded hole; 30d: Washer; 30e: Screw; 32: Tool mount; 32a: First boss; 32b: Second boss Platform (boss); 32c: Flange; 32d: Recess; 32e: Third boss; 32f: Bearing part; 32g: Flow path; 32h: Threaded groove; 34, 114: Cutting tools; 34a: Through hole; 34b: Another side; 34c: One side; 34d: Thickness; 34d1: First thickness; 34d2: Second thickness; 36: Pressing flange; 36a: Protrusion; 36b: Central hole; 36c: Flange surface; 36d: Annular surface; 36e: Through hole; 36e1: Opening; 36f: Annular surface; 38: Rotary joint; 38a: Boss; 38b: Annular groove; 38c: Suction path; 40: Solenoid valve; 42: Suction source; 44: Door; 46: First conveying unit; 46a: Suction Attached unit; 46b: Holding mechanism; 48: Second conveying unit; 48a: Adsorption unit; 50: Tool changing device; 52: Tool changing unit; 54: Base plate; 56: Lifting mechanism; 58: First support member; 60: Multi-joint robot; 62: First rotating mechanism; 62a: First arm; 64: Second rotating mechanism; 64a: Second arm; 66: Third rotating mechanism; 68: Bracket; 70: Moving part; 72: Changing mechanism; 72a: Housing; 72b: Rotating shaft; 74: Holding fixture (holding part); 74a1, 74a2: Mounting position; 76: Tool storage part; 78: Storage plate; 78a: Upper surface; 78b: First recess; 78c: Second recess; 78d: Protrusion; 80: Storage box; 80a: Protrusion; 82: Rotating shaft; 84: Circular illumination; 86: Camera unit (thickness information acquisition unit); 88: Identification information; 90: Control unit; 94: Camera unit (thickness information acquisition unit); 94a: Reader (thickness information acquisition unit); 96: Camera unit (measuring unit); 102: Press nut; 102a: Internal thread; 102b: Annular groove; 104: Nut retainer; 106: Claw; 108: Rotating shaft; 110: Drive unit; 116: Base unit; 116a: Protrusion; 116b: Through hole; 116c: Flange surface; 116d: Annular surface; 116e: Annular surface; 118: Mold unit; 118a: Through hole; 118b: Second surface;118c: First surface; 118d: Thickness. Detailed Implementation

[0038] An embodiment of one aspect of the present invention will be described with reference to the accompanying drawings. Figure 1 This is a perspective view of the cutting device 2 according to the first embodiment. Figure 1 The X-axis (machining feed direction), Y-axis (indexing feed direction), and Z-axis (vertical direction, up and down direction) shown are mutually perpendicular.

[0039] In addition, Figure 1 In the diagram, a functional block represents a part of the structural element. The cutting device 2 has a base 4 that supports each structural element. A lift 6, which is raised and lowered by a lifting mechanism (not shown), is provided at the corner of the base 4.

[0040] A box 8 is placed on the upper surface of the lifting platform 6a of the elevator 6. Multiple pairs of support plates 8a, each capable of supporting a workpiece 11, are arranged at predetermined intervals along the height direction of the box 8.

[0041] The workpiece 11 is, for example, a disk-shaped wafer made of semiconductor material such as silicon. A circular cutting strip 13 with a diameter larger than that of the workpiece 11 is attached to the center of one side of the workpiece 11.

[0042] Additionally, a metal ring-shaped frame 15 is attached to one side of the outer periphery of the cutting strip 13. The workpiece 11 is stored in the box 8 as a workpiece unit 17 supported by the frame 15 across the cutting strip 13.

[0043] A circular opening 4a is formed in the area adjacent to the elevator 6 in the X-axis direction. A cleaning unit 10 for cleaning the workpiece 11 after cutting is arranged in the opening 4a. The cleaning unit 10 has a rotary table 12.

[0044] A nozzle (not shown) is disposed above the rotary table 12 for spraying a gas-liquid mixture of liquids such as pure water and air. A pair of guide rails 14 are disposed above the cleaning unit 10.

[0045] A pair of guide rails 14 move toward or away from each other along the Y-axis via a drive mechanism (not shown). The position of the workpiece unit 17 in the Y-axis direction is adjusted by the pair of guide rails 14.

[0046] A rectangular opening 4b, having a long side along the X-axis, is formed adjacent to the guide rail 14 on one side in the Y-axis direction. A rectangular worktable cover 16 is provided in the opening 4b.

[0047] Dustproof and drip-proof covers 18 that can extend and retract along the X-axis are provided on both sides of the worktable cover 16. A chuck worktable 20 for attracting and holding the workpiece unit 17 is provided above the worktable cover 16.

[0048] The upper surface of the chuck table 20 functions as a holding surface for attracting and holding the workpiece unit 17 using negative pressure generated by a suction source (not shown) such as an ejector. A pair of clamping units 20a for holding the workpiece unit 17 are provided on the table cover 16.

[0049] Additionally, a pair of dressing tables 22 are provided on the table cover 16. Each dressing table 22 holds a dressing plate (not shown) for dressing the cutting tool 34 (described later).

[0050] A rotary drive source (not shown) such as an electric motor is provided at the lower part of the chuck table 20 for rotating the chuck table 20 about a rotary axis that is approximately parallel to the Z-axis direction. A ball screw type X-axis moving mechanism (machining feed unit) (not shown) is provided at the lower part of the rotary drive source for moving the rotary drive source and the chuck table 20 along the X-axis direction.

[0051] The area in opening 4b adjacent to a pair of guide rails 14 in the Y-axis direction is the loading and unloading area for loading and unloading the workpiece 11. The area in opening 4b located on the X-axis side relative to the loading and unloading area is the cutting area for cutting the workpiece 11.

[0052] A cuboid cover 24, made of metal or the like, is provided above the cutting area. A pair of cutting units 26 are arranged in the space covered by the cover 24. Each cutting unit 26 is connected to a ball screw-type Z-axis movement mechanism (feed-in mechanism) (not shown).

[0053] Furthermore, the Z-axis movement mechanism is connected to a ball screw-type Y-axis movement mechanism (indexing feed mechanism) (not shown). Each cutting unit 26 moves along the Z-axis direction via the Z-axis movement mechanism and along the Y-axis direction via the Y-axis movement mechanism. Here, using... Figure 2 and Figure 3 The cutting unit 26 will be described.

[0054] Figure 2 This is an exploded perspective view of the cutting unit 26 of the first embodiment. Figure 3 This is a partial cross-sectional side view of the cutting unit 26. The cutting unit 26 has a cylindrical spindle housing 28.

[0055] A portion of a cylindrical spindle 30 is rotatably housed within the spindle housing 28. A rotary drive source (not shown) such as a servo motor is provided at the base end of the spindle 30.

[0056] The front end portion 30a of the spindle 30 protrudes from the spindle housing 28. A tool mount 32 is fixed to the front end portion 30a. The tool mount 32 has a first boss portion 32a, and a hole portion that engages with the front end portion 30a is formed on the inner side of the first boss portion 32a.

[0057] The tool mount 32 has a cylindrical second boss 32b (boss portion) that protrudes in the axial direction 30b (i.e., the Y-axis direction) of the spindle 30 toward the side opposite to the first boss portion 32a. The second boss portion 32b is inserted into a through hole 34a formed in an annular cutting tool 34 (in this embodiment, a hubless tool).

[0058] An annular flange 32c is provided on the base end side of the second boss portion 32b and at a position radially outward of the second boss portion 32b. When the second boss portion 32b is inserted into the cutting tool 34, the flange 32c can contact the other side 34b of the cutting tool 34.

[0059] In the radial direction of the second boss portion 32b, an annular recess 32d is formed between the second boss portion 32b and the flange portion 32c. The recess 32d functions as a bearing portion for the annular protrusion 36a of the pressing flange 36, which will be described later.

[0060] A third boss 32e is formed radially inward of the second boss 32b, protruding further from the second boss 32b. An annular bearing portion 32f for bearing the washer 30d is formed on the inner side of the third boss 32e.

[0061] With the washer 30d positioned on the bearing portion 32f, the screw 30e is inserted into the inner side of the third boss portion 32e. If the shaft portion of the screw 30e is tightened into the threaded hole 30c of the front end portion 30a, the bearing portion 32f is pressed by the head of the screw 30e via the washer 30d, thereby fixing the tool mount 32 to the front end portion 30a of the spindle 30.

[0062] A central hole 36b of an annular pressing flange 36 is inserted into the second boss portion 32b. The central hole 36b is formed radially in the pressing flange 36 at a position closer to the inside of the annular protrusion 36a.

[0063] An annular flange surface 36c (the other side of the pressing flange 36) is formed at a position outside the protrusion 36a. In addition, an annular surface 36d (the side of the pressing flange 36) is provided on the side opposite to the protrusion 36a and the flange surface 36c.

[0064] The openings 36e1 of the plurality of through holes 36e are exposed on the annular surface 36d. The plurality of through holes 36e are arranged at approximately equal intervals along the circumference of the pressing flange 36, such that they extend from the flange surface 36c to the annular surface 36d respectively.

[0065] With the flange surface 36c facing one side 34c of the cutting tool 34 located on the opposite side to the other side 34b, when negative pressure is applied to the annular surface 36d, the negative pressure is transmitted to the flange surface 36c through the through hole 36e. When one side 34c is attracted and held by the flange surface 36c, the flange surface 36c is in contact with one side 34c.

[0066] The cutting tool 34, which is attracted and held by the pressing flange 36, is disposed together with the pressing flange 36 in the tool mounting base 32. After being disposed in the tool mounting base 32, the annular surface 36f of the pressing flange 36, located between the protrusion 36a and the central hole 36b, is attracted and held on the side of the tool mounting base 32.

[0067] An opening is formed on the tool mounting base 32 at one end of the flow path 32g, which is located radially inside the recess 32d. An opening is formed on the outer peripheral side of the first boss portion 32a at the other end of the flow path 32g.

[0068] With the tool mount 32 fixed to the front end 30a, the cylindrical boss 38a located at the front end of the spindle housing 28 is situated on the outer periphery of the first boss 32a. An annular groove 38b is formed throughout the entire circumference of the inner periphery of the boss 38a.

[0069] A suction path 38c is connected in the annular groove 38b at a position corresponding to the top of the boss portion 38a. The suction path 38c is connected to a suction source 42, such as an injector, via a solenoid valve 40.

[0070] The rotary joint 38 is composed of the boss 38a, the first boss 32a, the main shaft 30, etc. When the solenoid valve 40 is in the open state, the negative pressure acts on the flow path 32g through the suction path 38c and the annular groove 38b.

[0071] The negative pressure attracts the annular surface 36f of the pressing flange 36 to the tool mounting base 32, and the cutting tool 34 is held by the pressing flange 36 and the flange portion 32c. In this way, the cutting tool 34 is mounted on the front end 30a of the spindle 30.

[0072] Here, return Figure 1Other structural elements of the cutting device 2 will be described below. A door 44 is provided on the side of the cover member 24 on the side of the loading and unloading area. When the door 44 is open, the chuck table 20 can move in and out relative to the interior of the cover member 24 (i.e., the cutting chamber).

[0073] A first conveying unit 46 is disposed above the base 4 in a manner that does not interfere with the cover component 24. The first conveying unit 46 is capable of moving along the X and Y axes via a first horizontal moving mechanism (not shown).

[0074] The first conveying unit 46 has a cylinder whose length is arranged along the Z-axis. An adsorption unit 46a is provided at the lower end of the rod constituting the cylinder. The adsorption unit 46a has a support member that is approximately cross-shaped when viewed from above and a plurality of adsorption heads (not shown) provided on the lower surface side of the support member.

[0075] The adsorption unit 46a adsorbs, for example, the frame 15 of the workpiece unit 17. A holding mechanism 46b capable of holding a portion of the frame 15 is provided at one end of the elevator 6 side of the support member.

[0076] An arm of a second conveying unit 48 is provided above the first conveying unit 46. The second conveying unit 48 can move along the X and Y axes via a second horizontal moving mechanism (not shown).

[0077] The second conveying unit 48 also has a cylinder whose length is arranged along the Z-axis. An adsorption unit 48a is provided at the lower end of the rod constituting the cylinder. The adsorption unit 48a has a support member that is approximately cross-shaped when viewed from above and multiple adsorption heads (not shown) provided on the lower surface side of the support member.

[0078] Here, the steps for cutting the workpiece 11 using the cutting device 2 will be briefly explained. First, the first conveying unit 46 pulls the workpiece unit 17 from the box 8 toward a pair of guide rails 14 while holding the frame 15 with the holding mechanism 46b.

[0079] After adjusting the position of the workpiece unit 17 in the Y-axis direction using a pair of guide rails 14, the first conveying unit 46 uses the adsorption unit 46a to adsorb the frame 15 and convey the workpiece unit 17 to the chuck worktable 20 located in the conveying area.

[0080] Then, the chuck table 20 moves toward the cutting area while holding the back side of the workpiece 11 in a suction-holding state. After alignment, the workpiece 11 is cut by the rotating cutting tool 34 by moving the chuck table 20 relative to the cutting unit 26 in the X-axis direction.

[0081] After cutting, the chuck table 20 returns to the loading / unloading area. Then, the second transport unit 48 uses the adsorption unit 48a to adsorb the frame 15 and transports the workpiece unit 17 from the chuck table 20 to the cleaning unit 10.

[0082] The rotary table 12 rotates while holding the back side of the workpiece 11 in a suction manner, and sprays a gas-liquid mixture from the nozzle onto the front side of the workpiece 11, thereby cleaning the workpiece 11. Then, the workpiece 11 is dried.

[0083] After cleaning and drying, the first conveying unit 46 uses the adsorption unit 46a to adsorb the frame 15 and convey the workpiece unit 17 to a pair of guide rails 14. Then, the holding mechanism 46b presses the workpiece unit 17 into the box 8.

[0084] As multiple workpieces 11 are cut, the cutting tool 34 wears down, thus requiring replacement. The cutting apparatus 2 of this embodiment includes a tool changing device 50 for replacing the washer-type cutting tool 34.

[0085] The tool changing device 50 includes a tool changing unit 52 for conveying and changing cutting tools 34 (see reference). Figure 4 ). Figure 4 This is a perspective view of the tool changing unit 52. The tool changing unit 52 has a base plate 54 whose position is fixed relative to the base 4.

[0086] A lifting mechanism 56 is provided on the substrate 54. The lifting mechanism 56 includes, for example, an electric motor (not shown) provided at the lower part of the substrate 54 and a drive pulley (not shown) connected to the rotation shaft of the electric motor.

[0087] A driven pulley (not shown) is provided on the upper part of the base plate 54. A toothed endless belt (not shown) is mounted on the drive pulley and the driven pulley, and a portion of the toothed endless belt is connected to the first metal support member 58.

[0088] The first support member 58 moves up and down along the Z-axis in conjunction with the movement of the lifting mechanism 56. Alternatively, the lifting mechanism 56 can be a ball screw type. A multi-joint robot 60 is mounted on the first support member 58.

[0089] The articulated robot 60 has a first rotating mechanism 62, which has a rotational drive source such as a motor arranged with its rotation axis substantially parallel to the Z-axis direction. One end of a first arm 62a is mounted on the rotation axis of the first rotating mechanism 62.

[0090] A second rotating mechanism 64 is mounted at the other end of the first arm 62a. The second rotating mechanism 64 has a rotation drive source such as an electric motor whose rotation axis is arranged substantially parallel to the Z-axis direction. One end of the second arm 64a is mounted on the rotation axis of the second rotating mechanism 64.

[0091] A third rotating mechanism 66 is mounted at the other end of the second arm 64a. The third rotating mechanism 66 has a rotation drive source, such as an electric motor, whose rotation axis is arranged approximately parallel to the Z-axis direction. A metal bracket 68 is mounted on the rotation axis of the third rotating mechanism 66.

[0092] A replacement mechanism 72 for changing the cutting tool 34 is fixed on the bracket 68. The lifting mechanism 56 and the articulated robot 60 constitute the moving part 70 that moves the replacement mechanism 72. Figure 5 This is a side view of the replacement mechanism 72.

[0093] The replacement mechanism 72 has a generally cylindrical housing 72a. Inside the housing 72a is a rotation drive source (not shown), such as an electric motor, for rotating the housing 72a about a rotation axis 72b located approximately at the center of the cylinder.

[0094] A pair of retaining fixtures 74 (retaining parts) are arranged on the side of the housing 72a in such a way that they clamp the axis of rotation 72b. Each retaining fixture 74 can be detachably used to retain one side 34c of the cutting tool 34.

[0095] The retaining fixture 74 has a bottomed cylindrical frame made of metal or the like. Near the opening inside the frame is a ring-shaped lip (not shown) used for attaching or detaching the pressing flange 36. This lip is made of an elastic material such as rubber, resin, or an elastomer.

[0096] Multiple first openings (not shown) are formed on the front side of the lip along the circumference of the lip. Each first opening is connected to a first flow path (not shown) and a second flow path (not shown). The first flow path is connected to an suction source (not shown) such as an injector, and the second flow path is connected to an air supply source (not shown) for the jet air.

[0097] Solenoid valves (not shown) are respectively installed in the first flow path and the second flow path. When the first flow path is in the open state and the second flow path is in the closed state, negative pressure is transmitted to the first opening. For example, the pressing flange 36 is attracted and held by the lip by this negative pressure.

[0098] Conversely, when the first flow path is closed and the second flow path is open, air is injected from the first opening. Air injection is used, for example, when separating the pressing flange 36 from the lip.

[0099] Additionally, a ring-shaped non-contact attraction part (not shown) made of metal or the like is provided between the inner peripheral side of the frame and the outer peripheral side of the lip. Multiple second openings (not shown) are formed along the circumference of the non-contact attraction part on its outer peripheral side.

[0100] Each of the second openings is connected to the aforementioned air supply source (not shown) via a third flow path (not shown). A solenoid valve (not shown) is also installed in the third flow path. When the third flow path is opened and air is ejected from each of the second openings, a swirling flow is formed, and according to Bernoulli's theorem, a negative pressure is generated near the center of the swirling flow.

[0101] The negative pressure thus created is applied via the pressing flange 36 and held in place by the retaining fixture 74 in the tool storage section 76 (see reference). Figure 6 The cutting tool 34 is used for attraction and retention. Figure 6 This is a perspective view of the tool storage section 76.

[0102] The tool storage section 76 has a disc-shaped storage plate 78. In this embodiment, the storage plate 78 is formed of a generally transparent material (e.g., acrylic resin) that allows visible light to pass through.

[0103] Multiple first recesses 78b are formed along the circumference of the upper surface 78a of the storage plate 78 for storing the storage boxes 80 respectively. A generally transparent resin storage box 80 is disposed in each of the first recesses 78b.

[0104] In addition, Figure 6 For convenience, one storage box 80 is omitted. A disc-shaped protrusion 80a is formed in the center of the storage box 80. One cutting tool 34 is stored in one storage box 80 by means of a through hole 34a in the protrusion 80a.

[0105] Additionally, a second recess 78c for receiving the pressing flange 36 is formed on the upper surface 78a side. The second recess 78c is an annular recess, and a cylindrical protrusion 78d is provided in the center of the recess, which is inserted into the central hole 36b of the pressing flange 36.

[0106] A pressing flange 36 is housed in the second recess 78c with its annular surface 36d facing upwards. The lower surface of the central portion of the storage plate 78 is connected to the rotation shaft 82. A ring light 84 is disposed at a position outside the rotation shaft 82 and below the storage plate 78.

[0107] A camera unit (thickness information acquisition unit) 86 is arranged facing upwards below the through-hole of the ring illumination 84. The camera unit 86 has imaging elements such as an objective lens, a CMOS (Complementary Metal-Oxide-Semiconductor) image sensor or a CCD (Charge-Coupled Device) image sensor. The camera unit 86 acquires images of the identification information 88 set in the storage box 80 or the cutting tool 34.

[0108] The identification information consists of barcodes, QR codes, text, graphics, and symbols. Figure 6 In the example shown, the identification information 88 is set on the storage box 80, but the identification information 88 can also be set on the cutting tool 34 (see reference). Figure 9 (A)).

[0109] Alternatively, the identification information 88 can be printed directly on the storage box 80 or the cutting tool 34, or a seal with the identification information 88 printed on it can be pasted onto the storage box 80 or the cutting tool 34.

[0110] The cutting tool 34 is formed, for example, by mixing abrasive grains such as diamond or cBN (cubic boron nitride) into a bonding material such as metal, ceramic, or resin. Therefore, the surface of the cutting tool 34 has irregularities caused by the abrasive grains.

[0111] In contrast, the surface of the storage box 80 has less unevenness compared to the surface of the cutting tool 34. Therefore, compared to setting the identification information 88 on the surface of the cutting tool 34, the method of setting the identification information 88 on the surface of the storage box 80 can acquire an image of the identification information 88 more accurately by the camera unit 86.

[0112] Identification information 88 includes, for example, the thickness 34d of the cutting tool 34 (see reference). Figure 3 ), outer diameter, inner diameter, type of abrasive, abrasive particle size, concentration, type of adhesive, serial number, and information to identify the storage box 80 to be stored, etc.

[0113] Control unit 90 of cutting device 2 (refer to) Figure 1 The image acquired by the camera unit 86 is analyzed and read to obtain information about the thickness 34d of the cutting tool 34, which is set to various values ​​from 10 μm to 5 mm.

[0114] The control unit 90 is, for example, composed of a computer, including a processor (processing device) represented by a CPU (Central Processing Unit), main storage devices such as DRAM (Dynamic Random Access Memory), SRAM (Static Random Access Memory), and ROM (Read Only Memory), as well as auxiliary storage devices such as flash memory, hard disk drives, and solid-state drives.

[0115] The auxiliary storage device stores software containing a prescribed program. By following this software, the processing device and the like operate, thus realizing the function of the control unit 90. The auxiliary storage device also stores a program for reading information such as the thickness 34d of the cutting tool 34 based on the image acquired by the camera unit 86.

[0116] The program for reading information such as thickness 34d decodes codes, for example, when the identification information 88 is composed of one-dimensional barcodes, two-dimensional barcodes, etc. Additionally, the program can perform optical character recognition (OCR) when the identification information 88 is composed of text.

[0117] The control unit 90 also controls the actions of the elevator 6, cleaning unit 10, guide rail 14, chuck worktable 20, cutting unit 26, first conveying unit 46, second conveying unit 48, tool changing device 50, etc.

[0118] The control unit 90 causes the Y-axis movement mechanism of the cutting unit 26, the lifting mechanism 56, the multi-joint robot 60, etc. to operate, thereby keeping the fixture 74 at least in the installation position and the disengagement position.

[0119] The mounting position of the retaining fixture 74 refers to the position of the retaining fixture 74 that attracts and holds the cutting tool 34 when the other side 34b of the cutting tool 34 is at or below a predetermined distance relative to the flange 32c of the tool mount 32 (see reference). Figure 7 (A) Figure 7 (B) Figure 8 (A) and Figure 8 (B)

[0120] For example, when the fixture 74 is held in the mounting position, the other side 34b of the cutting tool 34 contacts the flange 32c of the tool mount 32. Alternatively, when the fixture 74 is held in the mounting position, a small gap (e.g., about 0.1 mm to 1.0 mm) may be formed between the other side 34b and the flange 32c.

[0121] Additionally, the disengaged position of the retaining fixture 74 refers to the position of the retaining fixture 74 that attracts and holds the cutting tool 34 when the cutting tool 34 is located away from the tool mount 32 (for example, see reference). Figure 9 (A)).

[0122] For example, when the retaining fixture 74 is in the disengaged position, the other side 34b of the cutting tool 34 is located at a position separated from the front end of the third boss portion 32e by a predetermined distance in the axial direction 30b. Next, the steps for changing the cutting tool 34 using the retaining fixture 74 will be described.

[0123] Before changing the cutting tool 34, the mounting position of the holding fixture 74 is first set (teaching process). In the teaching process, for example, using an optical camera (not shown) installed on the cutting device 2, the operator sets the spatial coordinates of the mounting position while observing the position of the holding fixture 74.

[0124] Specifically, while the cutting tool 34 with a specified thickness 34d is attracted and held by the holding fixture 74 via the pressing flange 36, the cutting unit 26 and the holding fixture 74 move relative to each other along the Y-axis direction (axial direction 30b), thereby determining the installation position and storing the spatial coordinates of the installation position in the control unit 90.

[0125] Furthermore, the aforementioned observation, advance / retreat, and decision-making are performed using a display input device (e.g., a touch panel) provided on the cutting device 2. After the teaching process, the cutting tool 34 is replaced at an appropriate time (replacement process).

[0126] During the changeover process, firstly, information such as the thickness 34d of the new cutting tool 34 is obtained using the camera unit 86 (see reference). Figure 6 Next, the changing mechanism 72 is moved to the tool storage section 76 by the moving part 70, and the new cutting tool 34 is attracted and held by a holding fixture 74 by pressing the flange 36.

[0127] Next, the changing mechanism 72 is moved into the interior of the cover member 24 via the door 44, so that another retaining fixture 74, different from one retaining fixture 74, is opposed to the pressing flange 36 mounted on the tool mounting seat 32.

[0128] Then, the cutting unit 26 is moved via the Y-axis moving mechanism in such a way that the spindle 30 approaches another holding fixture 74, and the other holding fixture 74 is used to attract and hold the pressing flange 36 mounted on the tool mount 32 and the used cutting tool 34. Meanwhile, the solenoid valve 40 connected to the rotary joint 38 is in the closed state at this time.

[0129] After the used cutting tool 34 is held in place by another retaining fixture 74, the cutting unit 26 is moved (retracted) so that the other retaining fixture 74 moves away from the tool mount 32 along the Y-axis. As a result, the other retaining fixture 74 moves relative to the tool mount 32 and the spindle 30 and moves toward the disengaged position.

[0130] Next, after rotating the changing mechanism 72 180 degrees about the rotation axis 72b, the cutting unit 26 is moved (advanced) so that a holding fixture 74 approaches the tool mount 32 along the Y-axis. As a result, the holding fixture 74 moves relative to the tool mount 32 and the spindle 30 and moves toward the mounting position.

[0131] Alternatively, during the replacement process, the pressing flange 36 already installed on the tool mounting base 32 can be replaced without replacing the cutting tool 34. Specifically, first, with the used cutting tool 34 and pressing flange 36 held in place by a holding fixture 74, the holding fixture 74 is moved toward the tool storage section 76.

[0132] Then, after placing the used cutting tool 34 in the empty storage box 80, a new cutting tool 34 is held in place by pressing the flange 36 using a retaining fixture 74. Afterwards, the retaining fixture 74 is positioned in the mounting position. This allows for the replacement of the cutting tool 34.

[0133] The mounting position of a retaining fixture 74 is adjusted according to the thickness 34d of the new cutting tool 34. Figure 7 Figure (A) shows the case where a new cutting tool 34 with a first thickness 34d1 is mounted on the tool mount 32.

[0134] The first thickness 34d1 is larger than the thickness 34d of the cutting tool 34 used in the teaching process. In this case, the control unit 90 reduces the advance of the cutting unit 26 based on the difference between the thicknesses 34d and 34d1, thereby adjusting the mounting position of a holding fixture 74.

[0135] Therefore, even when a new cutting tool 34 with a first thickness 34d1 different from the set thickness 34d is installed on the tool mounting base 32, damage to the new cutting tool 34 and the flange portion 32c can be prevented.

[0136] Figure 7 Figure (B) shows the case where a new cutting tool 34 having a second thickness 34d2 is mounted on the tool mount 32. The second thickness 34d2 is smaller than the thickness 34d of the cutting tool 34 used in the teaching operation.

[0137] In this case, the control unit 90 increases the advance of the cutting unit 26 based on the difference between the thicknesses 34d and 34d2, thereby adjusting the mounting position of a retaining fixture 74. Therefore, damage to the new cutting tool 34 and the flange 32c can be prevented, and the new cutting tool 34 and the pressing flange 36 can be properly positioned in the tool mounting base 32.

[0138] Figure 8 (A) is Figure 7 A magnified view of (A). Figure 8 (B) is Figure 7 A magnified view of (B). For example... Figure 8 As shown in (A), when a cutting tool 34 with a relatively thick first thickness 34d1 is mounted on the tool mount 32, the control unit 90 will hold the front end of the fixture 74 in the mounting position 74a1 (see reference). Figure 8 (B)

[0139] In contrast, when a cutting tool 34 with a relatively thin second thickness 34d2 is mounted on the tool mount 32, such as Figure 8 As shown in (B), the control unit 90 will hold the front end of the fixture 74 in a mounting position 74a2 that is closer to the flange 32c than the mounting position 74a1.

[0140] Next, a modified example of the method for obtaining the thickness information of the cutting tool 34 will be described. Figure 9 (A) is a diagram showing the case where an image of the identification information 88 provided on the cutting tool 34 is obtained using a camera unit (thickness information acquisition unit) 94, which is different from the camera unit 86 of the tool storage unit 76.

[0141] The camera unit 94 is fixed at any position on the base 4, for example. When the other side 34b of the cutting tool 34, which is held by the holding fixture 74 via the pressing flange 36, is opposite the camera unit 94, the camera unit 94 can acquire an image of the identification information 88 provided on the other side 34b.

[0142] Alternatively, the camera unit 94 can be a portable type that the operator can hold in their hand. In this case, by bringing the camera unit 94 close to the tool storage section 76, the operator can obtain an image of the identification information 88 provided in the storage box 80 or the cutting tool 34 through the camera unit 94.

[0143] Alternatively, the camera unit 94 may be provided in the tool changing mechanism 72 of the tool changing unit 52. In this case, when the fixture 74 is held close to the cutting tool 34 disposed in the tool storage section 76, the camera unit 94 can acquire an image of the identification information 88 provided in the storage box 80 or the cutting tool 34.

[0144] However, if the rotation axis 82 of the tool storage section 76 is arranged in a predetermined orientation that is approximately perpendicular to the Z-axis direction, an image of the identification information 88 can also be obtained by using the optical axis of the objective lens (not shown) and the camera unit 86 arranged in that predetermined direction.

[0145] Figure 9 Figure (B) shows a case where the camera unit (measuring unit) 96 acquires an image of the thickness 34d of the cutting tool 34 in another variation. The camera unit 96 can be fixed at any position on the base 4. Alternatively, the camera unit 96 can also be a portable type that can be held by the operator.

[0146] For example, such as Figure 9 As shown in (B), if the positions of the holding fixture 74 and the camera unit 96 are adjusted so that the central axis of the cutting tool 34 is approximately perpendicular to the optical axis of the objective lens (not shown) of the camera unit 96, and the camera unit 96 is positioned on the side of the cutting edge, an image of the cutting edge can be obtained.

[0147] The acquired image is processed by a prescribed program installed in the control unit 90. The actual length corresponding to one pixel is predetermined, and the thickness 34d is calculated by converting the number of pixels in the thickness direction of the cutting tool 34 into the actual length using the prescribed program.

[0148] Alternatively, as the measurement unit, a reflective laser displacement meter (not shown) with one or two sensor heads can be used instead of camera units 94 and 96. The sensor head has a semiconductor laser that emits a laser beam. Additionally, the sensor head has a light-receiving element that receives reflected light from the laser beam illuminating the object being measured.

[0149] For example, two sensor heads are arranged in such a way that the cutting tool 34 is sandwiched in the middle and facing each other. The thickness 34d is calculated by subtracting the distance from one sensor head to the other surface 34b and the distance from the other sensor head to one surface 34c from the distance between the two sensor heads.

[0150] Furthermore, the calculation of thickness 34d can also be performed using a processor located in the reflective laser displacement meter. Additionally, the acquisition of information about the thickness 34d of the cutting tool 34 is not limited to image acquisition based on camera units 86, 94, 96 or thickness measurement based on the laser displacement meter.

[0151] For example, if the identification information 88 is a barcode or QR code, a reader (scanner) 94a can also be used as a thickness information acquisition unit to read the identification information 88 (see reference). Figure 9 (A)). The reader 94a has a light source, a line sensor or area sensor that receives reflected light from the light source, and a processor that decodes the signal received by the sensor.

[0152] Alternatively, if the identification information 88 is a barcode, the reader 94a may also include: a light source capable of illuminating a laser beam; a multifaceted mirror that scans the laser beam; a sensor that receives reflected light; and a processor that decodes the signal received by the sensor.

[0153] Alternatively, for example, if an IC (Integrated Circuit) tag or RFID (Radio Frequency Identifier) ​​tag storing information about the thickness 34d is provided on the cutting tool 34, a non-contact reader (thickness information acquisition unit) 94a, such as an IC reader or RFID reader that reads information from the IC tag or RFID tag, can be used instead of the camera unit 86, 94, 96.

[0154] Next, the second embodiment will be described. Figure 10 This is an exploded perspective view of the cutting unit 100 according to the second embodiment. Figure 11 This is a partial cross-sectional side view of the cutting unit 100 according to the second embodiment. The cutting unit 100 does not have a rotary joint 38.

[0155] In the cutting unit 100, instead of using suction based on negative pressure, a pressing nut 102 with an internal thread 102a formed on the inner circumferential side is fastened in the threaded groove 32h of the third boss portion 32e formed in the tool mounting seat 32, thereby using the pressing flange 36 and the flange portion 32c to clamp the cutting tool 34.

[0156] Therefore, a cutting tool 34 is mounted on the front end 30a of the spindle 30. In the second embodiment, similarly to the first embodiment, the control unit 90 adjusts the mounting position of the retaining fixture 74 based on the difference from the set thickness 34d. This prevents breakage of the cutting tool 34 and damage to the flange portion 32c.

[0157] An annular groove 102b is formed on the outer peripheral side of the press nut 102 for use when holding the press nut 102. The press nut 102 is held by the nut retaining part 104 of the changing mechanism 72 (see reference). Figure 4 , Figure 5 And rotate.

[0158] like Figure 4 and Figure 5 As shown, the nut retaining part 104 has four claws 106 for retaining the outer periphery of the pressing nut 102. The base end of each claw 106 is connected to the rotating shaft 108.

[0159] The rotating shaft 108 is connected to a drive unit 110, such as a motor. When the drive unit 110 is activated, each claw portion 106 rotates around the rotating shaft 108. Figure 5 It can also rotate in the opposite direction, as shown in the diagram.

[0160] For example, when the nut retaining part 104 is rotated in one direction, the pressing nut 102 is fastened to the third boss part 32e, and when the nut retaining part 104 is rotated in another direction, the pressing nut 102 is removed from the third boss part 32e.

[0161] Next, the third embodiment will be described. Figure 12 This is an exploded perspective view of the cutting unit 112 of the third embodiment. Figure 13 This is a partial cross-sectional side view of the cutting unit 112 in the third embodiment.

[0162] The cutting unit 112 of the third embodiment does not have a washer-type cutting tool 34, but has a hub-type cutting tool 114. This differs from the first embodiment. The cutting tool 114 has an annular base portion 116 formed of a metal such as aluminum alloy.

[0163] The base portion 116 has an annular protrusion 116a corresponding to the protrusion 36a. A through hole 116b is formed in the radial direction of the base portion 116 at a position closer to the protrusion 116a. The second boss portion 32b of the tool mounting seat 32 is inserted into the through hole 116b.

[0164] In the radial direction of the base portion 116, an annular flange surface 116c is formed on the outer side of the protrusion 116a. The annular grinding portion 118, which functions as a cutting edge, is fixed to the base portion 116 by an adhesive in a state where the edge of its through hole 118a contacts the outer periphery of the protrusion 116a and the first surface 118c contacts the flange surface 116c.

[0165] Thus, in the third embodiment, the base portion 116 and the grinding portion 118 are integrated by fixing the grinding part 118 to the outer periphery of the base portion 116. However, no through hole 36e is formed on the base portion 116.

[0166] When the retaining fixture 74 is used to attract and retain the annular surface 116d (i.e., one side of the cutting tool 114) located on the side opposite to the protrusion 116a and the flange surface 116c, the cutting tool 114 is attracted and retained by the retaining fixture 74.

[0167] When the cutting tool 114 held by the retaining fixture 74 is positioned in the tool mounting base 32, the mounting position of the retaining fixture 74 is adjusted, for example, so that the protrusion 116a enters the recess 32d and the second surface 118b (i.e., the other side of the cutting tool 114) located on the opposite side of the first surface 118c contacts the flange 32c.

[0168] Next, the annular surface 116e located inside the protrusion 116a is attracted toward the tool mounting base 32 by the rotary joint 38, thereby mounting the cutting tool 114 onto the tool mounting base 32.

[0169] The thickness 118d of the grinding part 118 is the length from the second surface 118b to the first surface 118c. The thickness of the base part 116 is approximately constant in any cutting tool 114, but the thickness 118d of the grinding part 118 is set to various values, for example, from 10 μm to 5 mm.

[0170] In the third embodiment, when the retaining fixture 74 holding the new cutting tool 114 is positioned in the mounting position, the control unit 90 adjusts the mounting position of the retaining fixture 74 according to the difference between the thickness 118d set in the teaching process, just as in the first embodiment.

[0171] This prevents breakage of the cutting tool 114 and damage to the flange portion 32c. Next, the fourth embodiment will be described. Figure 14 This is an exploded perspective view of the cutting unit 120 according to the fourth embodiment. Figure 15 This is a partial cross-sectional side view of the cutting unit 120 of the fourth embodiment.

[0172] In the cutting unit 120 of the fourth embodiment, similarly to the third embodiment, a hub-type cutting tool 114 is mounted on the tool mounting base 32. However, the cutting unit 120 does not have a rotary joint 38.

[0173] In the cutting unit 120, suction based on negative pressure is not utilized, unlike in the second embodiment (see reference). Figure 10 and Figure 11Similarly, the cutting tool 114 is held by using the pressing nut 102 and the flange portion 32c to fasten the pressing nut 102 to the threaded groove 32h.

[0174] In the fourth embodiment, similarly to the first embodiment, the control unit 90 adjusts the mounting position of the holding fixture 74 that holds the new cutting tool 114 based on the difference between the thickness 118d set in the teaching process and the thickness 118d. This prevents breakage of the cutting tool 114 and damage to the flange 32c.

[0175] Furthermore, the structure and method of the above embodiments can be appropriately modified to implement them without departing from the purpose of the present invention. For example, in the cutting units 26 and 112 that use negative pressure to attract the cutting tools 34 and 114 toward the tool mounting base 32 (see...) Figure 2 , Figure 3 , Figure 12 , Figure 13 In this context, it can also be used with cutting units 100 and 120 (refer to...). Figure 10 , Figure 11 , Figure 14 , Figure 15 Similarly, the press nut 102 is fastened to the third boss 32e of the tool mounting seat 32.

Claims

1. A tool changing device for use in a cutting device that cuts a workpiece using an annular cutting tool mounted on the front end of a spindle via a tool mounting seat, characterized in that, The tool mount has: A cylindrical boss, which, while fixed to the front end of the spindle, protrudes along the axial direction of the spindle and inserts into the through hole of the cutting tool; and An annular flange portion, located at the base end of the boss portion, protrudes radially outward from the boss portion. This flange portion is capable of contacting the cutting tool when the cutting tool is inserted into the boss portion. The tool changing device has the following features: A retaining part that can be easily attached to and detached to hold one side of the cutting tool; A moving part that causes the retaining part, which holds the cutting tool in a state, to move forward and backward relative to the spindle in the axial direction of the spindle, positioning the retaining part at least in a mounting position where the other side of the cutting tool located on the opposite side is at a predetermined distance from the flange of the tool mount, or in a disengaged position where the cutting tool is away from the tool mount; and The thickness information acquisition unit is used to acquire information about the thickness of the cutting tool. The mounting position of the retaining part is adjusted according to the thickness of the cutting tool obtained by the thickness information acquisition part.

2. The tool changing device according to claim 1, characterized in that, The thickness information acquisition unit includes a camera unit, a reader, or a measurement unit. The camera unit is used to acquire an image of the identification information set on the cutting tool or the storage box for storing the cutting tool. The reader is used to read the identification information. The measurement unit measures the thickness of the cutting tool.

3. The tool changing device according to claim 1 or 2, characterized in that, An annular pressing flange is mounted on the tool mounting base to clamp the cutting tool together with the flange portion. The pressing flange has: The central hole is inserted into the boss portion; and A through hole is provided on the outside of the central hole, extending from one side of the pressing flange to the other side of the pressing flange. The retaining part attracts and retains the opening exposed on one side of the pressing flange in the through hole, thereby attracting and retaining the cutting tool via the other side of the pressing flange.

4. The tool changing device according to claim 1 or 2, characterized in that, This cutting tool has the following characteristics: The annular base portion is held by the retaining portion; and The annular grinding part is fixed to the outer periphery of the base part. The retaining part attracts and retains one side of the base portion, thereby attracting and retaining the cutting tool.

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