Cutting device

Abstract

The present invention provides a cutting device that reduces the amount of cutting chips remaining on the front surface of a workpiece after cutting the workpiece while supplying a liquid to the cutting tool and the workpiece on one side. The workpiece is cut while supplying a liquid from directly above the upper end of the cutting tool toward the upper end. In this case, the liquid mostly exits the cutting tool in a direction approximately parallel to the front surface of the workpiece, and then reaches the front surface of the workpiece due to air resistance and gravity. Therefore, the speed of most of the liquid slows down before it comes into contact with the front surface of the workpiece. As a result, in the present invention, even if the cutting chips attached to the vicinity of the outer periphery of the cutting tool exit from the cutting tool and are carried into the liquid as an opportunity to come into contact with the liquid, the possibility of the cutting chips included in the liquid sticking and remaining on the front surface of the workpiece can be reduced.

Description

Technical Field

[0001] This invention relates to a cutting device. Background Technology

[0002] Chips for devices such as ICs (Integrated Circuits) and LSIs (Large Scale Integrations) are typically manufactured by dividing a workpiece (workpiece) obtained by stacking a functional layer containing conductive and insulating films on the front side of a disk-shaped semiconductor substrate.

[0003] Specifically, the workpiece is divided into multiple regions by predetermined dividing lines arranged in a grid pattern, called spacers, and each region contains a device. Furthermore, the workpiece is divided along the spacers to manufacture a chip of the device.

[0004] Such workpiece division is performed, for example, using a cutting device comprising: a chuck table for holding the workpiece; and a cutting unit having a cutting tool mounted at the front end of a spindle for cutting the workpiece (see, for example, Patent Document 1). In this cutting device, the workpiece is cut by rotating the cutting tool and bringing its outer periphery into contact with the workpiece.

[0005] Patent Document 1: Japanese Patent Application Publication No. 2011-159823

[0006] When a workpiece is cut by a cutting tool, cutting chips are generated. Furthermore, the quality of the chips obtained by dividing the workpiece may be degraded. Therefore, the cutting of the workpiece in the cutting device is mostly carried out while providing the workpiece with a liquid (washing water) to rinse away the cutting chips.

[0007] Furthermore, frictional heat is generated when the workpiece is cut by a cutting tool. And when the cutting tool is heated by this frictional heat, the quality of the chips used to cut and / or divide the workpiece may deteriorate, making it difficult to cut the workpiece as intended. Therefore, the cutting of the workpiece in the cutting device is mostly performed while a liquid (cooling water) is supplied to the cutting tool for cooling the tool.

[0008] Water is used as both cleaning water and cooling water. Therefore, in a cutting device, water that functions as both cleaning water and cooling water can be supplied from a single nozzle (shared nozzle) while cutting the workpiece. For example, if the cutting tool rotates clockwise when viewed from the direction extending from the spindle, a shared nozzle supplying water can be provided at the right end of the cutting tool.

[0009] Specifically, the water supplied from the common nozzle first contacts the vicinity of the right end of the cutting tool to cool it. Then, the water in contact with the right end of the cutting tool rotates together with the cutting tool and is affected by the centrifugal force and gravity generated by this rotation.

[0010] Therefore, most of the water that comes into contact with the right end of the cutting tool leaves the cutting tool and collides with the workpiece in a downward direction from the right end. Furthermore, the water that collides with the workpiece flows across the front surface of the workpiece, washing away the cutting chips attached to it.

[0011] However, even with water supply, not all the cutting chips generated by the cutting tool cutting the workpiece can be washed away. For example, cutting chips sometimes adhere to the vicinity of the outer circumference of the rotating cutting tool.

[0012] Furthermore, cutting chips adhering to the outer periphery of the cutting tool sometimes detach from the tool and are carried into the water upon contact with water supplied from the common nozzle. Therefore, when water is supplied from the common nozzle, the water containing cutting chips collides with the workpiece. As a result, cutting chips become embedded in the surface of the workpiece, making it difficult to remove them with rinsing water. Summary of the Invention

[0013] In view of the above, the object of the present invention is to provide a cutting device that can reduce the amount of cutting chips remaining on the front side of the workpiece after cutting the workpiece while supplying fluid to the cutting tool and the workpiece.

[0014] According to the present invention, a cutting apparatus is provided, comprising: a chuck table having a holding surface substantially parallel to a horizontal direction for holding a workpiece; a cutting unit having a spindle extending along the horizontal direction for cutting the workpiece using an annular cutting tool mounted at the front end of the spindle; and a liquid supply unit for supplying liquid to the cutting tool and the workpiece, the liquid supply unit including a first nozzle supplying liquid from directly above the upper end of the cutting tool toward the upper end, the cutting tool rotating clockwise or counterclockwise when viewed from the direction extending from the spindle.

[0015] Preferably, the liquid supply unit includes a second nozzle that supplies liquid toward a region of the upper surface of the workpiece, the region being located directly below the right end of the cutting tool when viewed from the direction extending from the spindle and rotating clockwise, or directly below the left end of the cutting tool when viewed from the direction extending from the spindle and rotating counterclockwise.

[0016] In addition, it is preferable to form a liquid film by means of liquid supplied from the second nozzle, the thickness of which is greater in this region than in other regions.

[0017] In this invention, the workpiece can be cut while liquid is supplied upwards from directly above the upper end of the cutting tool. This liquid functions as both cooling water and cleaning water. Specifically, the liquid first contacts the vicinity of the upper end of the cutting tool to cool it, thus functioning as cooling water.

[0018] Next, most of the liquid that came into contact with the upper part of the cutting tool rotates with the cutting tool and is affected by the centrifugal force generated by this rotation. As a result, most of the liquid that came into contact with the upper part of the cutting tool leaves the cutting tool in the direction of rotation of the cutting tool (to the right if the cutting tool rotates clockwise when viewed from the direction extending from the spindle).

[0019] Furthermore, the liquid leaving the cutting tool traces a parabolic trajectory as it reaches the front of the workpiece due to air resistance and gravity. Additionally, the liquid reaching the front of the workpiece flows across it, washing away the cutting chips adhering to it, thus functioning as cleaning water.

[0020] Here, in this invention, most of the liquid leaves the cutting tool in a direction roughly parallel to the front of the workpiece and reaches the front of the workpiece due to air resistance and gravity. In other words, in this invention, the amount of liquid colliding with the front of the workpiece in a straight line is reduced, while the amount of liquid moving from near the top of the cutting tool toward the front of the workpiece while tracing a parabolic trajectory is increased.

[0021] Therefore, the velocity of most of the liquid just before it comes into contact with the workpiece (especially the vertical component of the liquid's velocity) is slower than the velocity of the water supplied from the aforementioned common nozzle (the nozzle that supplies water to the right end of the cutting tool, which rotates clockwise when viewed from the direction extending from the spindle) just before it collides with the workpiece.

[0022] As a result, in this invention, even if the cutting chips attached to the outer periphery of the cutting tool leave the cutting tool and are carried into the liquid by contact with the liquid, the possibility of cutting chips contained in the liquid getting stuck and remaining on the front side of the workpiece can be reduced. Attached Figure Description

[0023] Figure 1 It is a perspective view schematically showing an example of a workpiece.

[0024] Figure 2This is a perspective view schematically illustrating an example of a cutting device.

[0025] Figure 3 It is an exploded perspective view schematically showing a portion of the components of the cutting unit.

[0026] Figure 4 This is a schematic side view of the liquid supply unit.

[0027] Figure 5 It is a schematic side view showing the workpiece being cut and the cutting tool, etc.

[0028] Label Explanation

[0029] 11: Workpiece; 13: Substrate; 15: Functional layer; 17: Spacer; 19: Device; 2: Cutting device; 4: Base; 6: X-axis moving mechanism; 8: Guide rail; 10: X-axis moving plate; 12: Lead screw; 14: Motor; 16: Water tank; 18: Worktable base; 20: Theta stage; 22: Cover; 24: Chuck worktable; 26: Frame; 28: Perforated plate; 30: Support structure; 32: Y-axis moving mechanism; 34: Guide rail; 36: Y-axis moving plate; 38: Lead screw; 40: Motor; 42: Z-axis moving mechanism; 44: Guide rail; 46: Z-axis moving plate; 48: Lead screw; 50: Motor; 52: Cutting unit; 54: Spindle housing; 56: Spindle; 56a: Opening; 56b 58: Inner wall surface; 60: Cutting tool; 62: Mounting base; 62a: Flange; 62b: Abutment surface; 64: Protrusion; 64a: Outer wall surface; 66: Mounting base fixing bolt; 66a: Outer wall surface; 68: Flange; 68a: Opening; 70: Flange fixing nut; 70a: Opening; 70b: Inner wall surface; 72: Liquid supply unit; 74: Tool cover; 76: Nozzle; 78: Connecting part; 80: Piping; 82: Valve; 84: Liquid supply source; 86: Nozzle; 86a: Upper part; 86b: Lower part; 86c: Opening; 88: Connecting part; 90: Piping; 92: Valve; 94: Nozzle; 94a: Opening; 96: Connecting part; 98: Piping; 100: Valve; 102: Imaging unit. Detailed Implementation

[0030] The embodiments of the present invention will be described with reference to the accompanying drawings. Figure 1 This is a perspective view schematically illustrating an example of a workpiece being cut by a cutting device. Figure 1 The workpiece 11 shown has a disk-shaped substrate 13, which has cutouts formed at its outer edge to indicate crystal orientation. The substrate 13 is formed, for example, from silicon (Si), and a portion of the front (upper) surface of the substrate 13 has an impurity region doped with impurities.

[0031] Furthermore, there are no limitations on the material, shape, structure, and size of the substrate 13. The substrate 13 can be formed from materials other than silicon, such as semiconductors, ceramics, resins, and metals. Additionally, sometimes impurity regions are not provided on the substrate 13. Furthermore, a flat portion indicating crystal orientation, known as an orientation plane, can be formed on the outer edge of the substrate 13 instead of a notch.

[0032] A functional layer 15 comprising multiple insulating films and multiple conductive films is stacked on the front side of the substrate 13. The workpiece 11, consisting of the stacked substrate 13 and functional layer 15, is also referred to as a wafer.

[0033] Furthermore, in the workpiece 11, a portion of the substrate 13 (intrinsic semiconductor regions and impurity regions free of impurities) and a portion of the functional layer 15 (insulating film and conductive film) comprised of the region divided by multiple spacers 17 arranged in a grid pattern constitute a device (IC, etc.) 19. Moreover, there are no limitations on the type, number, shape, structure, size, and arrangement of the device 19.

[0034] Figure 2 This is a perspective view schematically illustrating an example of a cutting device that cuts the workpiece 11. For example, using... Figure 2 The cutting device 2 shown can cut the workpiece 11 along multiple spacers 17 to manufacture a chip of the device; can form grooves (half-cut) on the multiple spacers 17; and can remove the outer periphery of the workpiece 11 (edge ​​trimming); and so on.

[0035] in addition, Figure 2 The X-axis (machining feed direction, forward and backward direction) and Y-axis (indexing feed direction, left and right direction) shown are mutually perpendicular directions on the horizontal plane (horizontal direction). In addition, the Z-axis (cut-in feed direction, height direction) is perpendicular to the X-axis and Y-axis (vertical direction).

[0036] Figure 2 The cutting device 2 shown has a base 4 that supports each component. A ball screw type X-axis moving mechanism 6 is mounted on the base 4. The X-axis moving mechanism 6 has a pair of guide rails 8 extending along the X-axis direction.

[0037] An X-axis moving plate 10 is slidably connected to the upper surface of a pair of guide rails 8. Additionally, a lead screw 12 extending along the X-axis is disposed between the pair of guide rails 8. A motor 14 for rotating the lead screw 12 is connected to one end of the lead screw 12.

[0038] A ball screw is constructed by providing a nut (not shown) on the threaded outer circumferential surface of the lead screw shaft 12 to house the balls that circulate as the lead screw shaft 12 rotates. This nut is fixed to the lower surface of the X-axis moving plate 10. Therefore, when the lead screw shaft 12 is rotated by the motor 14, the X-axis moving plate 10 and the nut move together along the X-axis direction.

[0039] A water tank 16 is provided around the X-axis moving mechanism 6 to temporarily store the liquid supplied when cutting the workpiece 11. The liquid stored in the water tank 16 is discharged to the outside of the cutting device 2 through a drain pipe (not shown).

[0040] A worktable base 18 is fixed on the upper surface (front side) of the X-axis moving plate 10. A cylindrical θ-stage 20 is provided on the upper surface of the worktable base 18. A cover 22 with a rectangular upper surface is provided around the θ-stage 20.

[0041] A disc-shaped chuck table 24 is fixed on the upper surface of the θ stage 20. The chuck table 24 has a holding surface on its upper part for holding the workpiece 11. This holding surface is approximately parallel to the X-axis and Y-axis directions.

[0042] Additionally, the θ stage 20 is connected to a rotary drive source (not shown) such as an electric motor for rotating the θ stage 20 and the chuck table 24. The axes of rotation of the θ stage 20 and the chuck table 24 are parallel to the Z-axis direction and pass through the center of the holding surface of the chuck table 24.

[0043] The chuck worktable 24 has a disc-shaped frame 26 made of a metal such as stainless steel. A recess is formed on the upper surface of the frame 26, and a disc-shaped perforated plate 28 is fixed in the recess. The perforated plate 28 is made of porous ceramic and has an outer diameter that is approximately the same as the inner diameter of the recess.

[0044] The perforated plate 28 is connected to a suction source (not shown) such as a vacuum pump via a flow path formed in the frame 26. When the suction source is activated, a negative pressure is generated on the upper surface of the perforated plate 28 (the holding surface of the chuck stage 24). This negative pressure allows the workpiece 11 to be suctioned and held on the holding surface of the chuck stage 24.

[0045] Furthermore, the workpiece 11 can be held on the holding surface of the chuck table 24 in a frame unit integrated with the frame. This frame unit is, for example, composed of a disc-shaped adhesive tape, the workpiece 11 attached to the central region of the upper surface of the adhesive tape, and a frame attached to the region near the outer edge of the upper surface of the adhesive tape.

[0046] exist Figure 2In the cutting device 2 shown, the movement of the table base 18 along the X-axis direction is controlled by the X-axis movement mechanism 6. Furthermore, the chuck table 24 is supported on the table base 18 by means of the θ-stage 20. Therefore, the chuck table 24 moves together with the table base 18 along the X-axis direction.

[0047] A portal-shaped support structure 30 is provided on the base 4, arranged in a manner that spans the X-axis moving mechanism 6. A ball screw-type Y-axis moving mechanism 32 is provided on the front surface (front) of the support structure 30. The Y-axis moving mechanism 32 has a pair of guide rails 34 extending along the Y-axis direction.

[0048] A Y-axis moving plate 36 is slidably connected to the front surface (front side) of a pair of guide rails 34. Additionally, a lead screw 38 extending along the Y-axis is disposed between the pair of guide rails 34. A motor 40 for rotating the lead screw 38 is connected to one end of the lead screw 38.

[0049] A nut portion (not shown) is provided on the threaded outer circumferential surface of the lead screw shaft 38 to house the balls that circulate as the lead screw shaft 38 rotates, thus forming a ball screw. This nut portion is fixed to the rear surface (back side) of the Y-axis moving plate 36. Therefore, if the lead screw shaft 38 is rotated by the motor 40, the Y-axis moving plate 36 and the nut portion move together along the Y-axis direction.

[0050] A ball screw type Z-axis moving mechanism 42 is provided on the front surface (front side) of the Y-axis moving mechanism 32. The Z-axis moving mechanism 42 has a pair of guide rails 44 extending along the Z-axis direction.

[0051] A Z-axis moving plate 46 is slidably connected to the front surface (front side) of a pair of guide rails 44. Additionally, a lead screw 48 extending along the Z-axis is disposed between the pair of guide rails 44. A motor 50 for rotating the lead screw 48 is connected to one end of the lead screw 48.

[0052] A ball screw is constructed by providing a nut (not shown) on the threaded outer circumferential surface of the lead screw shaft 48 to house the balls that circulate as the lead screw shaft 48 rotates. This nut is fixed to the rear surface (back side) of the Z-axis moving plate 46. Therefore, when the lead screw shaft 48 is rotated by the motor 50, the Z-axis moving plate 46 and the nut move together along the Z-axis direction.

[0053] A cutting unit 52 is fixed to the lower part of the Z-axis moving plate 46. The cutting unit 52 has a cylindrical spindle housing 54 extending along the Y-axis direction. A portion of the components of the cutting unit 52 are housed in the spindle housing 54, and the remainder is exposed on the side of the spindle housing 54 near the chuck table 24.

[0054] Figure 3 This is an exploded perspective view schematically showing the components of the cutting unit 52 exposed outside the spindle housing 54. The cutting unit 52 has a spindle 56 with one end protruding from the front end of the spindle housing 54 and the rest housed within the spindle housing 54.

[0055] The spindle 56 is supported in the spindle housing 54 in a manner that allows it to rotate around an axis parallel to the Y-axis. Furthermore, the other end of the spindle 56 is connected to a rotary drive source (not shown), such as an electric motor, for rotating the spindle 56. This rotary drive source is housed in the spindle housing 54 and, for example, rotates the spindle 56 at 20,000 rpm to 50,000 rpm.

[0056] A mounting base 60 is installed at one end of the spindle 56 for mounting the cutting tool 58. In addition, an opening 56a is formed at one end of the spindle 56, and a threaded groove is provided on the inner wall surface 56b of the opening 56a.

[0057] The mounting base 60 has a flange portion 62 extending radially outward and a protrusion 64 protruding from the front of the flange portion 62. An opening 62a through the flange portion 62 is formed in the center of the flange portion 62.

[0058] Additionally, a fitting portion (not shown) is formed on the back side of the flange portion 62 to fit the front end of the main shaft 56. This fitting portion is provided at a position corresponding to the opening 62a.

[0059] With one end of the spindle 56 inserted into the mating portion formed in the flange portion 62, the mounting base 60 is fixed to the spindle 56 by screwing the mounting base fixing bolt 66 into the openings 62a and 56a. Furthermore, the outer wall surface 66a of the mounting base fixing bolt 66 is provided with threads corresponding to the threaded groove of the opening 56a.

[0060] The front side of the flange 62 forms an abutment surface 62b that abuts against the back side of the cutting tool 58. The abutment surface 62b is annular when viewed from the direction extending from the spindle 56 (Y-axis direction). The protrusion 64 is cylindrical, and threads are provided on the outer wall surface 64a of the protrusion 64.

[0061] An opening 58a is formed in the center of the cutting tool 58 for the protrusion 64 to be inserted through. The cutting tool 58 is mounted on the mounting base 60 by inserting the protrusion 64 through into the opening 58a.

[0062] With the cutting tool 58 mounted on the mounting base 60, an annular flange 68 is mounted on the front side of the cutting tool 58. An opening 68a is formed in the center of the flange 68, and a protrusion 64 of the mounting base 60 is inserted into the opening 68a.

[0063] The back side of flange 68 becomes an abutment surface (not shown) that abuts against the front side of cutting tool 58. This abutment surface is arranged in an annular shape in a manner corresponding to the abutment surface 62b of mounting base 60.

[0064] After installing the flange 68, screw the annular flange retaining nut 70 into the front end of the protrusion 64. This presses the flange 68 toward the mounting base 60, and the cutting tool 58 is clamped by the mounting base 60 and the flange 68.

[0065] That is, the front side of the cutting tool 58 abuts against the contact surface of the flange 68, and the back side of the cutting tool 58 abuts against the contact surface 62b of the mounting base 60, thereby holding the cutting tool 58 in a predetermined position. In addition, an opening 70a is provided on the flange fixing nut 70, and a threaded groove is formed on the inner wall surface 70b of the opening 70a.

[0066] A fluid supply unit 72 is provided around the components of the cutting unit 52 that are exposed outside the spindle housing 54 (see reference). Figure 2 The liquid supply unit 72 provides liquid to flush away the chips generated when the workpiece 11 is cut by the cutting tool 58 and to prevent the cutting tool 58 from being heated at this time.

[0067] Figure 4 This is a schematic side view of an example of the liquid supply unit 72 (viewed from the direction extending from the main axis 56 (Y-axis direction)). Additionally, in Figure 4 In the diagram, a simplified representation of some of the components of the liquid supply unit 72 is shown. Additionally, the spindle 56 and cutting tool 58 are also shown below. Figure 4 The explanation is based on the premise that the direction of the arrow shown is clockwise rotation.

[0068] The liquid supply unit 72 has a tool cover 74, which is configured to surround the area around the cutting tool 58 except for the area near the lower end B. A pair of L-shaped nozzles 76 for clamping the lower part of the cutting tool 58 are fixed inside the tool cover 74.

[0069] A pair of nozzles 76 are connected to a liquid supply source 84 via a connecting part 78 provided on the cutter cover 74, a pipe 80 connected to the connecting part 78, and a valve 82 in the pipe 80.

[0070] Multiple slits (not shown) are formed at the front end of each of the pair of nozzles 76 in a manner opposite to the cutting tool 58. Furthermore, when the valve 82 is in the open state, liquid supplied from the liquid supply source 84 is supplied from the multiple slits to the vicinity of the lower end B of the cutting tool 58 via the piping 80 and the connecting part 78.

[0071] Additionally, in the machining direction of the cutting tool 58, at the front ( Figure 4 A nozzle 86 is also provided on the right side of the cutting tool 58 shown. When viewed from the Y-axis direction, the nozzle 86 is away from the cutting tool 58, and when viewed from the X-axis direction, the nozzle 86 overlaps with the cutting tool 58. In addition, the nozzle 86 has: an upper part 86a, which extends along the Z-axis direction; and a lower part 86b, which bends from the lower end of the upper part 86a toward the cutting tool 58 side and extends in a straight line obliquely downward.

[0072] The nozzle 86 is connected to the liquid supply source 84 via a connecting part 88 provided on the cutter cover 74, a pipe 90 connected to the connecting part 88, and a valve 92 in the pipe 90.

[0073] An opening 86c is provided at the front end of the nozzle 86 (the lower end of the lower part 86b). In addition, when the workpiece 11 is cut by the cutting tool 58, the front end of the nozzle 86 faces the area of ​​the upper surface of the workpiece 11 located directly below the right end R of the cutting tool 58.

[0074] Furthermore, when the workpiece 11 is cut using the cutting tool 58, when the valve 92 is in the open state, the liquid supplied from the liquid supply source 84 is supplied from the front end of the nozzle 86 to the area on the upper surface of the workpiece 11 located directly below the right end R of the cutting tool 58 via the pipe 90 and the connection part 88.

[0075] In addition, a nozzle 94 is provided above the cutting tool 58. The nozzle 94 is located directly above the upper end T of the cutting tool 58 and extends along the Z-axis. The nozzle 94 is connected to the liquid supply source 84 via a connecting part 96 provided on the tool cover 74, a pipe 98 connected to the connecting part 96, and a valve 100 in the pipe 98.

[0076] An opening 94a is provided at the front end of the nozzle 94. In addition, the front end of the nozzle 94 faces the upper end T of the cutting tool 58. Furthermore, when the valve 100 is in the open state, the liquid supplied from the liquid supply source 84 is supplied from the front end of the nozzle 94 to the upper end T of the cutting tool 58 via the pipe 98 and the connection 96.

[0077] Additionally, a shooting unit 102 is fixed to the side of the main shaft housing 54 (see reference). Figure 2 The imaging unit 102 captures images of the workpiece 11 held by the holding surface of the chuck table 24.

[0078] The imaging unit 102 includes, for example, a light source such as an LED (Light Emitting Diode); an objective lens; and imaging elements such as a CCD (Charge Coupled Device) image sensor or a CMOS (Complementary Metal Oxide Semiconductor) image sensor.

[0079] exist Figure 2 In the cutting device 2 shown, the movement of the cutting unit 52 along the Y-axis is controlled by the Y-axis moving mechanism 32, and its movement along the Z-axis is controlled by the Z-axis moving mechanism 42. Furthermore, the liquid supply unit 72 and the imaging unit 102 are fixed to the cutting unit 52. Therefore, the liquid supply unit 72 and the imaging unit 102 move together with the cutting unit 52 along the Y-axis and / or Z-axis directions.

[0080] Furthermore, in the cutting device 2, the rotation of the cutting tool 58 is controlled by a rotation drive source housed in the spindle housing 54. The cutting device 2 is also capable of: cutting the workpiece 11 along multiple spacers 17 to manufacture a chip for a device; forming grooves on the multiple spacers 17; and removing the outer periphery of the workpiece 11; and so on.

[0081] For example, in the case of manufacturing a chip, after the cutting device 2 positions the lower end B of the cutting tool 58 below the lower surface of the workpiece 11 held by the holding surface of the chuck table 24, it rotates the cutting tool 58 and moves the chuck table 24 along the X-axis, thereby cutting the workpiece 11.

[0082] Here, in the cutting device 2, the workpiece 11 can be cut while supplying liquid to the cutting tool 58 via the nozzle 94 and to the workpiece 11 via the nozzle 86. Figure 5 This is a side view showing the workpiece 11 being cut and the cutting tool 58, etc.

[0083] In this case, the workpiece 11 can be cut while liquid L1 is supplied from directly above the upper end T of the cutting tool 58 via nozzle 94. Furthermore, the liquid L1 first contacts the vicinity of the upper end T of the cutting tool 58 to cool the cutting tool 58.

[0084] Next, most of the liquid L1 in contact with the upper end T of the cutting tool 58 rotates together with the cutting tool 58 and is affected by the centrifugal force generated by this rotation. Thus, most of the liquid L1 in contact with the upper end T of the cutting tool 58 rotates in the direction of rotation from the upper end T of the cutting tool 58 toward the cutting tool 58 (in... Figure 5 The cutting tool 58 leaves the paper in a direction from left to right.

[0085] Furthermore, the liquid L1 leaving the cutting tool 58 traces a parabolic trajectory as it reaches the front surface of the workpiece 11 due to air resistance and gravity. In addition, the liquid that reaches the front surface of the workpiece 11 flows on the front surface of the workpiece 11, washing away the cutting chips attached to the workpiece 11.

[0086] Here, in the cutting device 2, after most of the liquid L1 leaves the cutting tool 58 in a direction approximately parallel to the front of the workpiece 11, it reaches the front of the workpiece 11 due to air resistance and gravity. In other words, in the cutting device 2, the amount of liquid L1 that collides with the front of the workpiece 11 in a straight line decreases, while the amount of liquid L1 that moves from near the upper end T of the cutting tool 58 toward the front of the workpiece 11 while tracing a parabolic trajectory increases.

[0087] Therefore, the velocity of most of the liquid L1 just before it comes into contact with the workpiece 11 (especially the vertical component of the liquid's velocity) is slower than the velocity of the liquid supplied from the nozzle of the existing cutting device (supplying liquid to the right end R of the cutting tool 58) just before it comes into contact with the workpiece 11.

[0088] As a result, in the cutting device 2, even if the cutting chips attached to the outer periphery of the cutting tool 58 are taken into the liquid by contact with the liquid, the possibility of cutting chips contained in the liquid getting stuck and remaining on the front side of the workpiece 11 can be reduced.

[0089] In addition, such as Figure 5 As shown, when cutting the workpiece 11, the workpiece 11 can be cut while the liquid is supplied to the region 21 on the upper surface of the workpiece 11 located directly below the right end R of the cutting tool 58 via the nozzle 86.

[0090] In this case, liquid L2 spreads on the upper surface of the workpiece 11 to form a liquid film LF. Specifically, liquid L2 spreads radially from region 21, thus forming a liquid film LF with a greater thickness in region 21 than in other regions. Furthermore, the liquid film LF functions as a protective film protecting the upper surface of the workpiece 11.

[0091] Specifically, in the cutting device 2, even if the liquid containing cutting chips exits from the cutting tool 58 in a downward direction from near the right end R of the cutting tool 58, the liquid film LF can prevent the liquid containing cutting chips from colliding with the upper surface of the workpiece 11. Therefore, in the cutting device 2, the possibility of cutting chips contained in the liquid embedding and remaining on the front surface of the workpiece 11 can be further reduced.

[0092] Furthermore, while cutting device 2 is one embodiment of the present invention, cutting devices with different features from cutting device 2 are also included in the present invention. For example, in the present invention, the L-shaped pair of nozzles 76 and / or nozzles 86 may not be provided.

[0093] Alternatively, in the cutting device 2, the spindle 56 and the cutting tool 58 can be rotated counterclockwise when viewed from the direction extending from the spindle 56 (Y-axis direction). However, in this case, the configuration and / or structure of the nozzle 86 needs to be changed.

[0094] Specifically, the nozzle 86 should be positioned such that its tip faces the area on the upper surface of the workpiece 11 directly below the left end of the cutting tool 58 when the workpiece 11 is being cut by the cutting tool 58. As described above, this further reduces the possibility of cutting chips contained in liquid becoming embedded and remaining on the front surface of the workpiece 11.

[0095] In addition, the above-described embodiments and variations can be appropriately modified and implemented as long as they do not depart from the scope of the present invention.

[0096]

Example

[0097] A cutting apparatus having a nozzle of an embodiment and a cutting apparatus having a nozzle of a comparative example are prepared. The nozzle of the embodiment supplies liquid directly above the upper end of a cutting tool that rotates clockwise when viewed from a direction extending from the spindle on which the cutting tool is mounted at its front end. The nozzle of the comparative example supplies liquid to the right end of the clockwise rotating cutting tool. Furthermore, the nozzle of the embodiment is... Figure 4 and Figure 5 The nozzle corresponding to nozzle 94 shown.

[0098] The workpiece was cut in two states: one where liquid was supplied only from the nozzle of the embodiment (the embodiment) and the other where liquid was supplied only from the nozzle of the comparative example (the comparative example). The workpiece used for cutting was the same in both states. The spindle speed during cutting was 30,000 rpm.

[0099] Furthermore, the quantities of foreign matter with a size (diameter) of approximately 0.1 μm and a diameter of approximately 0.2 μm remaining on the upper surface of the workpiece after cutting were statistically analyzed. Table 1 shows the statistically analyzed quantities of foreign matter.

[0100] Table 1

[0101] Number of foreign objects around 0.1 μm Number of foreign objects around 0.2μm Example 34 11 Comparative example 226 34

[0102] As shown in Table 1, compared with the case where liquid is supplied to the workpiece while cutting it through the nozzle of the comparative example, the amount of foreign matter remaining on the upper surface of the workpiece can be reduced by supplying liquid to the workpiece through the nozzle of the embodiment while cutting it.

Claims

1. A cutting device, characterized in that, The cutting device has the following features: A chuck table has a retaining surface that is approximately parallel to the horizontal direction, which is used to hold the workpiece. A cutting unit having a spindle extending along the horizontal direction, which cuts the workpiece using an annular cutting tool mounted at the front end of the spindle; as well as A liquid supply unit that supplies liquid to the cutting tool and the workpiece. The liquid supply unit includes: The first nozzle, which supplies liquid from directly above the upper end of the cutting tool, rotates clockwise or counterclockwise when viewed from the direction extending from the spindle. as well as A second nozzle provides liquid toward the upper surface of the workpiece, the area being located directly below the right end of the cutting tool, which rotates clockwise when viewed from the direction extending from the spindle, or directly below the left end of the cutting tool, which rotates counterclockwise when viewed from the direction extending from the spindle. The second nozzle is located in front of the cutting tool in the direction of machining when viewed from the cutting tool. It does not supply liquid directly to the cutting tool from the second nozzle. Instead, it forms a liquid film by supplying liquid from the second nozzle. The thickness of this liquid film on the upper surface of the workpiece is greater in the area directly opposite the right end of the cutting tool (when viewed from the direction extending from the spindle) in the vertical direction than in other areas.

Images