Dressing method of saw blade

Abstract

To provide a dressing method which can reproduce sharpness of a saw blade without causing abrasion of the saw blade.SOLUTION: A dressing method of a saw blade of the invention includes: a preparation step in which a cutting device 1, comprising a chuck table 34 configured to hold a workpiece, cutting means 6 configured to rotatably support a spindle 24 attached with a saw blade 15 for cutting the workpiece held by the chuck table 34, and feeding means which feeds the chuck table 34 and the cutting means 6 relative to each other, is prepared; and a dressing step in which a dressing board 100 for adjusting a cutting blade 15b is held in the chuck table 34, the saw blade 15 is rotated in a direction opposite to a forward direction to feed the chuck table 34 and the cutting means 6 relative to each other, and the cutting blade 15b is cut into the dressing board 100 to be adjusted.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a method for dressing a saw blade. [Background technology]

[0002] A wafer having a plurality of devices such as ICs and LSIs formed on its surface along division lines is separated into individual device chips by a cutting machine equipped with a rotatable cutting blade. These chips are then used in electrical equipment such as mobile phones and personal computers.

[0003] Furthermore, ceramic capacitor chips used in electrical devices are formed by dividing a plate-shaped raw ceramic into individual ceramic capacitor chips and then sintering them.

[0004] To cut wafers, a cutting blade formed from an electroformed grinding wheel with diamond abrasive grains fixed with nickel plating is used, and to cut raw ceramics, a saw blade formed from ultra-hard steel and equipped with multiple saw blades with a forward rotation direction on the outer periphery of a circular base is used (see, for example, Patent Document 1).

[0005] When the cutting blade becomes clogged with cutting chips, the cutting blade cuts the dressing board, exposing the diamond abrasive grains from the plating layer and restoring the sharpness of the blade (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 04-179505 [Patent Document 2] JP 2012-187693 A Summary of the Invention [Problem to be solved by the invention]

[0007] When cutting raw ceramics or resin with the above saw blade, cutting chips adhere to the saw blade and the sharpness decreases. In order to remove the cutting chips adhered to the cutting blade and restore the sharpness, the saw blade is rotated in the forward direction, which is the inclined direction of the saw blade, to cut the dressing board in the same manner as the above cutting blade, but the cutting edge side of the saw blade is worn by the abrasive grains such as SiC that make up the dressing board, and the sharpness cannot be restored properly.

[0008] The present invention has been made in consideration of the above-mentioned facts, and its main technical object is to provide a dressing method that can restore the sharpness of a saw blade without wearing down the cutting edge side of the saw blade. [Means for solving the problem]

[0009] In order to solve the above-mentioned main technical problems, according to the present invention, there is provided a method for dressing a saw blade having a plurality of saw blades formed on the outer periphery of a circular base, the method including a preparation step of preparing a cutting device including a chuck table for holding a workpiece, cutting means for rotatably supporting a spindle on which a saw blade for cutting the workpiece held on the chuck table is attached, and processing feed means for processing and feeding the chuck table and the cutting means relatively, and a dressing step of holding a dressing board for trimming the saw blade on the chuck table, rotating the saw blade in the direction opposite to the forward direction to process and feed the chuck table and the cutting means relatively, and cutting the saw blade into the dressing board to trim the saw blade.

[0010] In the dressing step, the chuck table can be relatively fed for processing in a direction following the rotation direction of the saw blade. Also, in the dressing step, the chuck table may be relatively fed for processing in a direction against the rotation direction of the saw blade. Effect of the Invention

[0011] The saw blade dressing method of the present invention is a method for dressing a saw blade having a plurality of saw blades formed on the outer periphery of a circular base, with the rotation direction being specified as a forward direction, and includes a preparation step of preparing a cutting device including a chuck table for holding a workpiece, cutting means for rotatably supporting a spindle on which a saw blade for cutting the workpiece held on the chuck table is attached, and processing feed means for processing and feeding the chuck table and the cutting means relatively, and a dressing step of holding a dressing board for trimming the saw blade on the chuck table, rotating the saw blade in the opposite direction to the forward direction to process and feed the chuck table and the cutting means relatively, and cutting the saw blade into the dressing board to trim the saw blade, thereby efficiently removing cutting chips adhering to the saw blade and trimming the saw blade without the cutting edge side of the saw blade being worn by the dressing board, thereby restoring the sharpness of the saw blade. [Brief description of the drawings]

[0012] [Figure 1] FIG. [Diagram 2] 2 is an enlarged perspective view showing a spindle unit attached to the cutting device shown in FIG. 1. [Diagram 3] FIG. 3 is an exploded perspective view of the spindle unit shown in FIG. 2. [Figure 4] 4(a) is a perspective view showing a further exploded portion of the spindle unit shown in FIG. 3, and FIG. 4(b) is a perspective view showing a state in which a saw blade is attached to the spindle unit shown in FIG. [Diagram 5] FIG. 1A is a perspective view showing an embodiment of a method for dressing a saw blade of the present invention; FIG. 1B is a perspective view showing an embodiment different from the embodiment shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a method for dressing a saw blade constructed according to the present invention will be described together with a cutting apparatus suitable for carrying out the method for dressing a saw blade of the present invention.

[0014] 1 shows a cutting device 1. The cutting device 1 is disposed on a stationary base 2, and includes a holding means 3 for holding a workpiece, an X-axis feed means 5 for feeding the holding means 3 in the X-axis direction shown by the arrow X in the figure, a cutting means 6 for cutting a workpiece (not shown) held by the holding means 3, a chuck table 34 of the holding means 3, a Y-axis feed means 7 for indexing and feeding the cutting means 6 in the Y-axis direction shown by the arrow Y in the figure perpendicular to the X-axis direction, and a Z-axis feed means 8 for cutting and feeding the cutting means 6 in the Z-axis direction (up and down) shown by the arrow Z in the figure perpendicular to the X-axis direction and the Y-axis direction.

[0015] A pair of first guide rails 2a, 2a along the X-axis direction and a pair of second guide rails 2b, 2b along the Y-axis direction are disposed on the upper surface 2c of the stationary base 2. The holding means 3 includes a first movable body 31 movably disposed on the first guide rails 2a, 2a, a cylindrical member 32 fixed to the upper surface 31a of the first movable body 31, a cover member 33 fixed to the upper part of the cylindrical member 32, a chuck table 34 that protrudes from the upper surface of the cover member 33 and holds the workpiece by suction, and a plurality of clamps 35 (four in this embodiment) disposed at equal intervals on the outer periphery of the chuck table 34 and grip a frame (not shown) that supports the workpiece. Note that a suction means (not shown) is connected to the chuck table 34, and a negative pressure is generated on the holding surface of the chuck table 34 by operating the suction means.

[0016] The X-axis feed means 5 includes a servo motor 51 and a ball screw 52. The servo motor 51 is disposed at one end of the ball screw 52, ​​and the other end is rotatably supported by a bearing portion 2d disposed on the upper surface 2c of the base 2. The rotational motion of the servo motor 51 is transmitted and converted into linear motion by a ball screw mechanism constituted by a nut portion (not shown) disposed on the lower surface side of the first movable body 31 into which the ball screw 52 screws, and is converted into linear motion. This allows the first movable body 31 to advance and retreat in the X-axis direction along the first guide rails 2a, 2a with which the slide grooves 31b, 31b on the lower surface side of the first movable body 31 slidably engage.

[0017] The cutting means 6 is supported by the second movable body 53 and disposed at a rear position adjacent in the Y-axis direction to the area where the holding means 3 moves in the X-axis direction. The cutting means 6 includes a spindle unit 16. A blade cover 22 is disposed at the tip side of the spindle unit 16 to protect the cutting blade 14 fixed to the rotating spindle rotatably supported by the spindle unit 16. The spindle unit 16 is also integrally provided with an imaging means (not shown) for imaging the workpiece held by the holding means 3 and detecting the area to be processed. In addition to the illustrated cutting blade 14, a saw blade 15 (described later) can be attached to the rotating spindle (see FIG. 4(a)), and is appropriately replaced depending on the type of workpiece, processing conditions, etc.

[0018] The second movable body 53 includes a horizontal wall portion 53a and a vertical wall portion 53b erected on the horizontal wall portion 53a, and rail engagement portions 53c, 53c arranged on the lower surface side of the horizontal wall portion 53a slidably engage with the second guide rails 2b, 2b, and are configured to be movable in the Y-axis direction by the Y-axis feed means 7. The Y-axis feed means 7 includes a servo motor 71 and a ball screw 72 whose end is rotatably supported by a bearing portion 73 arranged on the base 2. The rotational motion of the servo motor 71 is transmitted by a ball screw mechanism formed of a nut portion (not shown) arranged on the lower surface side of the horizontal wall portion 53a that screws into the ball screw 72, and is converted into linear motion, causing the second movable body 53 to advance and retreat in the Y-axis direction along the second guide rails 2b, 2b.

[0019] A pair of third guide rails 54, 54 are provided on the side surface of the vertical wall portion 53b of the second movable body 53 along the Z-axis direction (up-down direction) indicated by the arrow Z (partially shown by dashed lines). A third movable body 55 functioning as a support member for supporting the spindle unit 16 is slidably attached to the third guide rails 54, 54, and is configured to be movable in the up-down direction (Z-axis direction) by the Z-axis feed means 8. The Z-axis feed means 8 includes a stepping motor 81 and a ball screw 82 (shown by dashed lines) which is connected to the stepping motor 81 and rotates, and whose end is supported by a bearing portion 83 (shown by dashed lines) which is arranged on the lower side of the side surface of the vertical wall portion 53b of the second movable body 53. The rotational motion of the stepping motor 81 is transmitted to a nut portion (not shown) arranged on the third movable body 55 which is screwed into the ball screw 82, thereby moving the third movable body 55 forward and backward along the third guide rails 54, 54 in the Z-axis direction. The stepping motor 81 is provided with a rotation speed detection means (e.g., a rotary encoder), and the actual rotation speed of the stepping motor 81 is output to a control means (not shown), thereby precisely controlling the position of the third movable body 55 in the Z-axis direction.

[0020] The control means includes a central processing unit (CPU) that executes calculations in accordance with a control program, a read-only memory (ROM) that stores the control program etc., a read / write random access memory (RAM) for temporarily storing calculation results etc., an input interface, and an output interface (details not shown in the figure), and controls each operating part of the cutting device 1.

[0021] Fig. 2 shows an enlarged view of the spindle unit 16 of the cutting means 6 attached to the cutting device 1 shown in Fig. 1. The spindle unit 16 includes a housing 20, a blade cover 22 attached to the tip of the housing 20, a rotating spindle 24 supported by the housing 20 so as to be rotatable about the Y-axis direction, and a spindle drive motor that rotates the rotating spindle 24. The direction indicated by the arrow R1 in Fig. 2 is the rotation direction of the rotating spindle 24 when the cutting blade 14 cuts the workpiece.

[0022] 2 and 3, the blade cover 22 includes a fixed cover 22a fixed to the tip of the housing 20, a removable cover 22b detachably attached to the tip of the fixed cover 22a via a screw 26, and a blade detection block 22c detachably attached to the upper part of the fixed cover 22a via a screw 28. Although not shown, a light emitting member and a light receiving member are disposed in the blade detection block 22c for detecting the state of the cutting blade 14. When replacing the cutting blade 14 with the saw blade 15, the above-mentioned removable cover 22b and blade detection block 22c are removed and replaced.

[0023] Fig. 4(a) shows a perspective view of the spindle unit 16 further disassembled. For convenience of explanation, the blade cover 22 is omitted in Fig. 4(a). As shown in the figure, the cutting blade 14 or the saw blade 15 is selected and attached to the spindle unit 16 depending on the type of workpiece, the processing conditions, etc. The cutting blade 14 is, for example, a blade formed by an electroformed grindstone in which diamond abrasive grains are fixed by nickel plating, and the saw blade 15 is, for example, a blade in which a plurality of saw blades 15b are formed on the outer periphery of a circular base 15a formed by super steel.

[0024] In the embodiment shown in Figs. 4(a) and (b), a description will be given of a saw blade 15 being mounted on the rotating spindle 24. As shown in the figures, an annular mount flange 21 that protrudes radially outward is provided on the outer peripheral surface of the tip side of the rotating spindle 24. A male thread 24a is formed on the outer peripheral surface of the rotating spindle 24 further on the tip side than the mount flange 21. The saw blade 15 is first mounted from the tip side of the rotating spindle 24, and then the annular detachable flange 23 is mounted. Then, a nut 25 is screwed onto the male thread 24a of the rotating spindle 24. As a result, as shown in Fig. 4(b), the saw blade 15 is sandwiched between the mount flange 21 and the detachable flange 23 from both sides in the Y-axis direction and fixed to the tip of the rotating spindle 24. Then, when the rotating spindle 24 is rotated by a spindle drive motor (not shown), the saw blade 15 rotates together with the rotating spindle 24.

[0025] Saw blade 15 is used when cutting green ceramics or plate-shaped resin members, and as can be seen from Figures 4(a) and (b), saw blade 15's saw blade 15 has a saw blade 15b that is formed so as to be inclined at an acute angle in one circumferential direction, and the direction of the inclination is defined as a forward direction along the rotation direction (direction indicated by R1 in the figure) when cutting a workpiece with saw blade 15. As shown in an enlarged partial view on the right side of Figure 4(b), saw blade 15b has cutting edge portion 15ba and back portion 15bb, and cutting edge portion 15ba faces the forward direction of saw blade 15.

[0026] When cutting a workpiece, such as raw ceramics, the saw blade 15 is rotated in the direction of rotation indicated by the arrow R1 in FIG. 4(b), and the above-mentioned X-axis feed means 5, Y-axis feed means 7, and Z-axis feed means 8 are operated to cut the cutting edge portion 15ba of the saw blade 15b of the saw blade 15 into the workpiece held on the chuck table 34 of the holding means 3, thereby performing cutting along a predetermined intended processing line.

[0027] As described above, by repeatedly performing cutting processing with saw blade 15, grinding waste adheres and accumulates between adjacent saw edges 15b of saw blade 15, making it difficult to properly cut the workpiece. Therefore, the dressing method for the saw blade described below is performed periodically or at any desired timing.

[0028] (preparation process) In carrying out the method for dressing a saw blade of this embodiment, first, a cutting device is prepared that includes a chuck table for holding a workpiece, cutting means for rotatably supporting a spindle on which a saw blade for cutting the workpiece held on the chuck table is attached, and processing feed means for relatively feeding the chuck table and the cutting means. More specifically, the preparation process is completed by preparing the above-mentioned cutting device 1.

[0029] (Dressing process) Next, a dressing process described below is performed. When performing the dressing process, first, a dressing board 100 for aligning the saw blade 15b of the saw blade 15 shown in Fig. 5(a) is held on the chuck table 34 of the cutting device 1. The dressing board 100 is typically a rectangular plate-like member, for example, a rectangular plate-like member in which general abrasive grains such as GC (Green Carborundum) and WA (White Alundum) are hardened with a bonding material such as resin or vitreous. In order to hold the dressing board 100 on the chuck table 34, the dressing board 100 is positioned at the center of an annular frame F having an opening Fa capable of accommodating the dressing board 100, and is held and integrated with the frame F via an adhesive tape T.

[0030] If the dressing board 100 is held and integrated with the frame F via the adhesive tape T, it is placed on the chuck table 34 of the holding means 3 of the cutting device 1, the frame F is sandwiched by the clamp 35, and suction means (not shown) on the holding surface of the chuck table 34 is operated to generate a negative pressure for suction holding. In addition, when the dressing board is formed in a disk shape and has the same size as the holding surface of the chuck table 34 or a size larger than the holding surface of the chuck table 34, the dressing board may be directly placed on the chuck table 34 for suction holding.

[0031] As described above, when the dressing board 100 is held on the chuck table 34, according to the shape of the dressing board 100, a predetermined cutting planned line is aligned in the X-axis direction of the cutting device 1, and alignment with the saw blade 15 is performed. At this time, the entire dressing board 100 is imaged by an imaging means (not shown), the position of the preset cutting planned line is specified on the dressing board 100, and the height of the surface 100a is detected.

[0032] 5(a), the saw blade 15 is rotated in the reverse direction indicated by the arrow R2 relative to the forward direction of the saw blade 15. Then, the saw blade 15 rotated at high speed in the reverse direction indicated by the arrow R2 is positioned on the cutting line aligned in the X-axis direction and cuts into the surface 100a, and the X-axis feed means 5 is operated to move the chuck table 34 in a direction following the rotation direction of the saw blade 15 indicated by the arrow R2, i.e., in the direction indicated by the arrow X1 in the figure, to feed the dressing board 100 for processing and form the cutting groove 110.

[0033] The above-mentioned cutting groove 110 is formed by rotating the saw blade 15 in the reverse direction (the direction indicated by arrow R2 in the figure) relative to the forward direction in which the saw blade 15 of the saw blade 15 is inclined, and cutting into the dressing board 100 from the back portion 15bb side of the saw blade 15b.This allows cutting chips adhering to the saw blade 15b to be efficiently removed, and the cutting edge portion 15ba side of the saw blade 15b to be straightened without being worn down by the dressing board 100, thereby restoring the sharpness of the saw blade 15b.

[0034] If the cutting chips are not sufficiently removed from the saw blade 15b of the saw blade 15 by only one cutting groove 110, the above-mentioned Y-axis feed means 7 is operated to index and feed the saw blade 15 to a position adjacent to the cutting groove 110 in the Y-axis direction where the cutting groove 110 is not formed, and the cutting groove 110 is formed in the same manner as described above. By performing these operations multiple times, the cutting chips attached to the saw blade 15b are more reliably removed, and the cutting edge portion 15ba of the saw blade 15b is smoothed by the dressing board 100 without being worn, and the sharpness can be restored.

[0035] The dressing method of the saw blade of this embodiment is not limited to the above embodiment, and may be implemented, for example, in the form shown in Fig. 5(b). In the embodiment shown in Fig. 5(b), similarly to the description based on Fig. 5(a), the saw blade 15 is rotated at high speed in the reverse direction indicated by the arrow R2 with respect to the forward direction of the saw blade 15 (the direction indicated by the arrow R1 in Fig. 4(a)). Then, the saw blade 15 rotated at high speed in the direction indicated by the arrow R2 is positioned on the cutting line aligned in the X-axis direction, and cuts from the surface 100a side, and the X-axis feed means 5 is operated to move the chuck table 34 in the direction against the rotation direction of the saw blade 15 indicated by the arrow R2, i.e., in the direction indicated by the arrow X2 in the figure, to feed the dressing board 100 for processing and form the cutting groove 112. In this embodiment, the saw blade 15 is rotated in the opposite direction (indicated by the arrow R2 in the figure) to the forward direction in which the saw blade 15b of the saw blade 15 is inclined, and the back 15bb of the saw blade 15b is cut into the dressing board 100, so that the cutting chips attached to the saw blade 15b are efficiently removed, and the cutting edge portion 15ba of the saw blade 15b is smoothed by the dressing board 100 without being worn, and the sharpness can be restored. In addition, the processing feed direction X2 of the dressing board 100 is the direction opposite to the rotation direction of the saw blade 15, and the relative speed of the saw blade 15b passing through the dressing board 100 is high, so that the effect of removing the cutting chips from the saw blade 15b can be expected to be greater.

[0036] Furthermore, the dressing method of the saw blade of the present invention is not limited to either Figure 5(a) or Figure 5(b) described above, but may alternately and continuously involve dressing by feeding the dressing board 100 for processing in the direction indicated by arrow X1 in Figure 5(a) and dressing by feeding the dressing board 100 for processing in the direction indicated by arrow X2 in Figure 5(b).

[0037] In the above-described embodiment, a dressing method was implemented in which the saw blade 15 was rotated in the opposite direction to the forward direction and the chuck table 34 was processed and fed in the X-axis direction to cause the saw blade 15b to cut into the dressing board 100 and shape the saw blade. However, the present invention is not limited to this, and dressing may be performed by holding the dressing board 100 on a fixed chuck table and processing and feeding the cutting means 6 side in the X-axis direction to cause the saw blade 15b to cut into the dressing board 100. [Explanation of symbols]

[0038] 1:Cutting device 2:Stationary base 2a: First guide rail 2b: Second guide rail 2c:Top surface 2d: Bearing part 3: Holding means 31: First moving body 32: Cylindrical member 33: Cover material 34: Chuck table 35: Clamp 5: X-axis feed means 51: Servo motor 52: Ball screw 53: Second moving body 54: Third guide rail 55: The third moving body 6:Cutting means 7: Y-axis feed means 71: Servo motor 72: Ball screw 8: Z-axis feed means 81: Stepping motor 82: Ball screw 83: Bearing part 14: Cutting blade 15: Saw blade 15a: Circular base 15b: Saw blade 15ba: cutting edge 15bb: back 16: Spindle unit 20: Housing 21: Mount flange 22: Blade cover 23: Detachable flange 24: Rotating spindle 100: Dressing board 110, 112: Cutting groove

Claims

1. A method for dressing a saw blade having a plurality of saw blades, each having a rotation direction defined in a forward direction, formed on an outer periphery of a circular base, comprising: a chuck table for holding a workpiece; and cutting means for rotatably supporting a spindle having a saw blade mounted thereon for cutting the workpiece held on the chuck table; a preparation step of preparing a cutting device including a processing feed means for relatively processing-feeding the chuck table and the cutting means; a dressing step in which a dressing board for shaping the saw blade is held on the chuck table, the saw blade is rotated in a direction opposite to the forward direction to relatively feed the chuck table and the cutting means for processing, and the saw blade is cut into the dressing board to shape the saw blade; 2. A method of dressing a saw blade comprising:

2. 2. A method for dressing a saw blade as claimed in claim 1, wherein in the dressing step, the chuck table is fed for processing in a direction following the direction of rotation of the saw blade.

3. 2. A method for dressing a saw blade as claimed in claim 1, wherein in the dressing step, the chuck table is relatively fed for processing in a direction opposite to the direction of rotation of the saw blade.

Images