JP2003326463A - Electrocast thin grinding wheel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thin grinding wheel capable of preventing such problems as burrs from occurring on a ground material such as electronic materials, particularly those on which different materials are laminated or those having a copper part of high ductility. <P>SOLUTION: This electrocast thin grinding wheel 10 comprises a generally disk-like grinding wheel body 11 formed by distributedly arranging super abrasive grains in the phase of a metal plating. A plurality of groove parts 13 are formed at the outer peripheral edge of the grinding wheel body 11, tips 14 formed of the single crystal or sintered body of a diamond or cBN are fixed onto the wall surfaces of the groove parts 13 in forward rotating direction of the grinding wheel body. Slits 15 extending in the radial direction of the grinding wheel body 11 are formed between the wall surfaces of the tips 14 in the forward rotating direction of the grinding wheel body and the wall surfaces of the groove parts 13 in the rearward rotating direction of the grinding wheel body. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electroformed thin blade grindstone used for cutting a work material such as an electronic material.

[0002]

2. Description of the Related Art In order to manufacture electronic parts, for example, a chip cut out from a wafer on which a circuit pattern is formed is placed on a lead frame made of Cu or the like, both members are bonded, and each chip is attached to the lead frame. A method of cutting the lead frame after encapsulating the whole with resin is adopted.

Recently, in consideration of increasing the number of electronic parts that can be manufactured at one time and downsizing of electronic parts, a plurality of chips are mounted instead of dividing each individual part and covering it with resin. The entire lead frame is sealed with resin,
A method of cutting the lead frame together with the resin layer and dividing the lead frame into individual parts (packages) is also adopted.

Conventionally, a disc-shaped thin blade grindstone 1 as shown in FIG. 4, for example, has been used for cutting such electronic parts. This thin blade grindstone 1 is formed by dispersing superabrasive grains such as diamond and cBN in a metal plating phase made of Ni, Co, or an alloy thereof, and a plurality of slits 1a are provided at the blade edge. There is. Slit 1
a is an electric discharge machine using a wire or the like, or a grindstone for the purpose of taking in shavings generated during cutting and easily discharging them to the outside to prevent clogging and guiding more cooling water to the cutting surface. It is formed at a predetermined interval from the outer peripheral edge toward the inner peripheral side in the radial direction by a grinding process using the above.

In such a thin blade grindstone 1, the inner peripheral side portion is clamped by a mounting flange and mounted on the grindstone shaft, and is tightened and fixed by a nut. While being rotated around the axis of the grindstone shaft, the outer peripheral side portion is The work material can be cut and processed by the cutting edge portion.

[0006]

However, in such a thin blade grindstone 1, although the workability is improved by the slit 1a, it is intermittently contacted with the work material by providing the slit 1a. In order to be
The corners of the outer peripheral edge of the slit 1a portion are easily worn. If the cutting performance of the grindstone deteriorates due to such wear of the cutting edge, burrs are likely to be generated in the cutting trace, and especially at the end of the work material or the part where the cutting lines intersect each other, the work material is weakly supported and fixed. Therefore, there is a problem that the work material escapes due to the pressure of the cutting edge, which easily causes burrs. Further, when cutting a work material in which different materials are laminated with the above-mentioned thin blade grindstone 1 such as when cutting a substrate having copper wiring on the surface, the wiring portion or lead frame portion made of copper having high ductility is stretched. There is a problem that it may be cut off after being blown off, and the wiring may be peeled off because it is difficult to cut. Furthermore, the corners of the cutting edge are worn or Cu chips from the cut lead frame adhere to the cutting edge and become clogged.
If the machinability of any part of the cutting edge deteriorates, it causes burrs due to cutting failure, and it is difficult to remove the burrs even if the cutting edge of the sharp cutting edge comes into contact with the work material. There is a problem in that

The present invention has been made in view of the above problems, and causes problems such as burrs in work materials such as electronic materials, particularly those in which different materials are laminated or those having a highly ductile copper portion. An object of the present invention is to provide a thin blade grindstone capable of preventing the occurrence of problems such as burrs when cutting an easily workable material.

[0008]

In order to solve the above-mentioned problems, an electroformed thin blade grindstone according to the invention of claim 1 has a substantially disk-like shape in which superabrasive grains are dispersed in a metal plating phase. In an electroformed thin blade grindstone having a grindstone body, a plurality of grooves are formed on the outer peripheral edge of the grindstone body, and a chip made of a single crystal of diamond or cBN or a sintered body is fixed to the wall surface of the groove facing forward in the rotation direction of the grindstone body. A slit extending in the radial direction of the grindstone body is formed between the wall surface of the tip facing the front side in the grindstone body rotating direction and the wall surface of the groove facing rearward in the grindstone body rotating direction.

According to the present invention, since a part of the slit of the main body of the grindstone that abuts the work material is formed by a high-hardness tip made of diamond or cBN, clogging around the slit can be prevented, so that the cutting property can be improved. It is possible to suppress the deterioration of the burrs, prevent the burrs and the copper wiring from peeling off, and reliably cut the work material along a predetermined cutting line. That is,
Since the rear side of the slit that is likely to be clogged because it comes into contact with the work material is formed with a chip that has high hardness and is not clogged, clogging of this part can be prevented, so burrs due to cutting work etc. Can be prevented more effectively.

The electroformed thin blade grindstone according to the invention of claim 2 is the electroformed thin blade grindstone of claim 1, wherein the maximum thickness of the tip is
It is characterized in that it is thicker than the thickness of the whetstone body.

According to the present invention, since the thickness of the tip is larger than the thickness of the main body of the grindstone, the work piece is not scratched and pulled out by the abrasive grains on the side surface of the main body of the grindstone, and burr is less likely to occur. Enables precision processing of electronic component materials.

An electroformed thin blade grindstone according to a third aspect of the present invention is the electroformed thin blade grindstone according to the first or second aspect, wherein the tip is formed of a thin portion and a thick wall formed by gradually increasing the thickness from the thin portion. And a thin portion is located on the front side in the rotational direction of the grindstone main body with respect to the slit, and a thick portion is located on the rear side in the rotational direction with respect to the slit.

According to the present invention, the sharp rake angle can be maintained by processing the work material with the tip formed so that the blade thickness of the blade tip gradually increases as the grindstone body rotates. Therefore, good machinability can be maintained. Further, the thin-walled portion having a small blade thickness is more strongly brought into contact with the work material than the thick-walled portion having a large blade thickness, so that the work material is less likely to be stretched and the cutting process can be performed more reliably. Also, 1
Even if burrs are generated by cutting with one tip, the burrs can be removed or reduced by the next tip.

An electroformed thin blade grindstone according to a fourth aspect of the present invention is the electroformed thin blade grindstone according to the third aspect, wherein the slit is a first slit or a thin wall whose thin portion is arranged on one side surface side of the grindstone main body. The part is one of the second slits arranged on the other side surface side of the grindstone body, and a part of the plurality of slits is the first slit, and the remaining slits are the second slits. It is characterized by being.

According to the present invention, it is possible to perform the cutting process while surely removing or reducing the burr on the one side surface side by the first slit having the thin portion provided on the one side surface side. Similarly, it is possible to perform the cutting process while surely removing or reducing the burr on the other side surface side by the second slit having the thin portion on the other side surface side. Therefore, by providing both slits and alternately arranging them, it is possible to more reliably cut the work material while preventing burr formation.

An electroformed thin blade grindstone according to a fifth aspect of the present invention is characterized in that, in the electroformed thin blade grindstone according to the first to fourth aspects, the slit is formed in a constant shape in the radial direction.

According to the present invention, since the slits are formed in a constant shape in the radial direction, even when the grindstone body is worn by cutting, the slits having the same shape as before the wear are formed. Longer service life and cost reduction in cutting are realized.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view of an electroformed thin blade grindstone according to the present embodiment, and FIG. 2 is an enlarged view showing a main part of the electroformed thin blade grindstone.

As shown in FIG. 1, the electroformed thin blade grindstone 10 according to the present embodiment has a substantially disk-shaped grindstone main body 11 that is driven to rotate about an axis, and the outer peripheral edge of the grindstone main body 11 has a cutting edge portion. It is 12. The grindstone main body 11 is formed in a disc shape by arranging diamonds dispersedly in a metal binding phase made of, for example, Ni, Co, or an alloy thereof. The electroformed thin blade grindstone 10 is mounted on the grindstone shaft while being clamped by the mounting flange at the inner peripheral side portion thereof, and is also tightened and fixed by the nut. Then, while rotating around the axis of the grindstone shaft, the blade-shaped portion 12 cuts the plate-shaped work material along the cutting line.

The grindstone body 11 has a plurality of groove portions 1 on the outer peripheral edge.
.. are formed, and a chip 14 made of a diamond sintered body is fixed to each of the groove portions 13. The tip 14 has a circumferential width of the grindstone main body 11 smaller than that of the groove portion 13, and as shown in FIG.
Of the slit 14 extending in the radial direction of the grindstone body 11 between the wall surface of the tip 14 facing forward in the rotation direction of the grindstone body 11 and the groove portion 13 facing the rearward direction in the rotation direction of the grindstone body 11. 15 is formed.
The slits 15 are required to take in shavings generated during cutting of the work material and to easily discharge them to the outside to prevent clogging, and to guide the cooling water more to the cutting surface. The shape.

[0021]

EXAMPLE An electroformed thin blade grindstone 10 which is an example of the present invention is described below.
A cutting test using a conventional electroformed thin blade grindstone 1 as a comparative example will be described. Electroformed thin blade grindstone 10 of the present invention
Is dispersion-plated with diamond of 40/60 μm in nickel sulfamate solution (6.5 A, about 3 hours),
After manufacturing a disk-shaped grindstone having an outer diameter of 80 mm and a thickness of 0.3 mm, a hole of 40 mm was formed on the inner peripheral side by wire electric discharge machining. Then, 16 grooves 13 having a width of 3 mm and a depth of 3 mm in the circumferential direction are provided by wire electric discharge machining, and each groove 13 has a chip 14 made of a diamond sintered body having a width of 2 mm, a depth of 3 mm and a thickness of 0.3 mm. Attached, width 1m
m slits 15 were formed.

A conventional electroformed thin blade grindstone 1 as a comparative example is obtained by dispersion-plating diamond (40/60 μm) in a nickel sulfamate solution (6.5 A, about 3 hours) to obtain an outer diameter φ.
After manufacturing a disc-shaped grindstone having a thickness of 100 mm and a thickness of 0.3 mm, a hole having a diameter of 40 mm was formed on the inner peripheral side by wire electric discharge machining, and further, an outer diameter of 80 mm was ground using a cylindrical grinder. Then, 1m in width in the circumferential direction by wire electric discharge machining
16 slits 1a having a depth of 3 mm and a depth of 3 mm were formed.

The cutting processing conditions are as shown below. -Work material Copper plate (50 mm x 50 mm, thickness 0.5 mm) -Used machine Fujikoshi dicing machine SHG20P-Number of revolutions 20000 [rev / min] -Cooling medium water-Feeding rate 10 [mm / sec] -Cut depth 0.6 [mm] -Tape fixing The size of copper burr generated on the fixing tape side by the cutting process performed under the above conditions was measured with a tool microscope. The results are shown in Table 1.

[0024]

[Table 1]

As shown in Table 1, in the electroformed thin blade grindstone 10 which is an example of the present invention, the maximum burr size is 2 as compared with the conventional one.
It decreased from 00 μm to 130 μm. Further, in the present invention, the average size of the burr is from 80 μm in the conventional case to 80 μm.
It was found to be as small as μm and the effect of preventing burr formation was high.

Next, another embodiment of the present invention will be described with reference to FIG. FIG. 3 is an enlarged view showing the vicinity of the groove portion 23 in the grindstone body 21 of the electroformed thin blade grindstone 20 according to the present embodiment. Electroformed thin blade grindstone 20 according to the present embodiment
Like the electroformed thin blade grindstone 10, the grindstone main body 2 has a substantially disk-shaped grindstone main body 21 that is driven to rotate about an axis.
The outer peripheral edge of No. 1 is the blade edge portion 22. This whetstone body 2
No. 1 is formed in a disk shape by arranging diamond in a metallic bonding phase made of Ni, Co, or an alloy thereof, for example. The electroformed thin blade grindstone 20 is mounted on the grindstone shaft while being clamped by the mounting flange at the inner peripheral side portion thereof, and is tightened and fixed by the nut. Then, while rotating around the axis of the grindstone shaft, the blade-shaped portion 22 cuts the plate-shaped work material along the cutting line.

The grindstone body 21 has a plurality of groove portions 2 on its outer peripheral edge.
, 23, ... Are formed, and each of the groove portions 23 has a first chip 24A made of a diamond sintered body.
One of the second chip 24B and the second chip 24B is fixed. The first chip 24A and the second chip 24B are
It has a thin wall portion 24a and a thick wall portion 24b formed by gradually increasing the wall thickness from the thin wall portion 24a. The thin wall portion 24a is located on the front side in the rotation direction of the grindstone body 21, and is thicker on the rear side in the rotation direction. The meat portion 24b is fixed so as to be located. That is, in each of the chips 24A and 24B, a plurality of cutting regions in which the blade thickness is gradually increased are formed in the grindstone body 21.

In the first tip 24A, as shown in FIG. 3A, the thin portion 24a has one side surface 21 of the grindstone body 21.
It is arranged on the a side and forms a first slit 25a between itself and the groove 23. On the other hand, the second chip 24B
As shown in FIG. 3 (b), the thin portion 24 a is arranged on the other side surface 21 b side of the grindstone body 21, and the groove portion 23
The second slit 25b is formed between the first and second slits. Each slit formed in the plurality of groove portions 23, 23, ... With the chips 24A, 24B is either the first slit 25a or the second slit 25b, and in the present embodiment, the first slit 25a and The second slits 25b are arranged alternately. Further, each slit is formed in a constant shape in the radial direction, and the shape is maintained even when the grindstone body 21 or each tip is worn.

According to the electroformed thin blade grindstone 20 of this embodiment,
When the cutting edge portion 22 processes the work material as the grindstone body 21 rotates, the cutting edge thickness gradually increases at each tip portion, so that a sharp cutting edge can be maintained even if the tip wears, and one side surface The burr on one side can be removed, and then the chip having the thin portion 24a on the other side can remove or reduce the burr on the other side surface. Since the chips 24A and 24B are made of a high hardness diamond sintered body, they have high wear resistance,
Cutting can be performed while preventing burrs of the work material and peeling of the wiring.

The shapes, combinations and the like of the constituent members shown in the above embodiments are merely examples, and various modifications can be made without departing from the spirit of the present invention based on design requirements and the like. For example, in the above embodiments,
Although the tip is brazed to the grindstone body, it can be fixed by other means such as plating. Further, the tip is not limited to the diamond sintered body described above, and may be a diamond single crystal, a cBN sintered body or a single crystal.

[0031]

As described above, according to the electroformed thin blade grindstone according to the invention of claim 1, the rear side of the slit abutting the work piece is formed by a diamond or cBN chip having high hardness. Since the chip cuts the copper wiring portion that is prone to burrs, it is possible to suppress deterioration of cuttability, prevent burrs and copper wiring from peeling off, and reliably cut the work material along a predetermined cutting line. .

According to the electroformed thin blade grindstone of the second aspect of the present invention, since the thickness of the tip is larger than the thickness of the grindstone main body, cutting in the width direction is performed at the tip portion, so that the rotating grindstone main body It is possible to suppress the occurrence of burrs due to the side surface coming into contact with the work material, and it is possible to perform precision machining of electronic component materials.

According to the electroformed thin blade grindstone of the third aspect of the present invention, the tip formed so that the blade thickness of the blade tip gradually increases with the rotation of the grindstone main body processes the work material, whereby the sharpness is improved. The cutting edge can be maintained and burrs can be removed.
Further, even if burrs are generated by cutting with one tip, the burrs can be removed or reduced by the next tip.

According to the electroformed thin blade grindstone of the fourth aspect of the present invention, the first slit having the thin portion on any one of the side surfaces is used to surely remove or reduce the burr on the one side surface. Processing can be performed. Similarly, it is possible to perform the cutting process while surely removing or reducing the burr on the other side surface side by the second slit having the thin portion on the other side surface side. Therefore, by providing both slits and alternately arranging them, it is possible to more reliably cut the work material while preventing burr formation.

According to the electroformed thin blade grindstone of the fifth aspect of the present invention, since the slit is formed in a constant shape in the radial direction, even when the grindstone body is worn by cutting, it has the same shape as before the wear. Since the slit is formed, the life of the grindstone is extended, and the cost reduction in cutting is realized.

[Brief description of drawings]

FIG. 1 is a plan view showing an electroformed thin blade grindstone according to an embodiment of the present invention.

FIG. 2 is an enlarged perspective view showing a main part of the electroformed thin blade grindstone shown in FIG.

FIG. 3 is an enlarged perspective view showing a main part of an electroformed thin blade grindstone according to another embodiment of the present invention.

FIG. 4 is a plan view showing a conventional thin blade grindstone.

[Explanation of symbols]

10,20 Electroformed thin blade grindstone 11,21 Wheel body 13,23 Groove 14 chips 15 slits 24A first chip 24B Second chip 24a thin part 24b thick part 25a First slit 25b Second slit

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 3C063 AA02 AB03 BA04 BA12 BA24                       BB02 BC02 BG01 BG05 BH05                       CC02 CC12 EE10 EE31 FF30

Claims (5)

[Claims] 1. An electroformed thin blade grindstone having a substantially disk-shaped grindstone main body in which superabrasive grains are dispersed in a metal plating phase, wherein a plurality of groove portions are formed on an outer peripheral edge of the grindstone body, and the groove portions are formed. Of a diamond or cBN single crystal or sintered body is fixed to the wall surface of the whetstone main body which faces the front in the rotation direction of the whetstone main body, and the wall surface of the chip facing forward in the whetstone body rotation direction and the whetstone body rotation of the groove portion. An electroformed thin blade grindstone, characterized in that a slit extending in the radial direction of the grindstone body is formed between the wall surface and the wall surface facing rearward. 2. The electroformed thin blade grindstone according to claim 1, wherein the maximum thickness of the tip is not less than the thickness of the grindstone body. 3. The tip has a thin-walled portion and a thick-walled portion formed by gradually increasing the thickness from the thin-walled portion, and the thin-walled portion is located on the front side in the rotation direction of the grindstone body. The electroformed thin blade grindstone according to claim 1 or 2, wherein the thick-walled portion is fixed so as to be located on the rear side in the rotation direction. 4. The slit has a first slit in which the thin portion is arranged on one side surface side of the grindstone body or a second slit in which the thin portion is arranged on the other side surface side of the grindstone body. The slit according to claim 3, wherein a part of the plurality of slits is the first slit and the remaining slits are the second slits. Thin cast blade whetstone. 5. The electroformed thin blade grindstone according to claim 1, wherein the slit is formed in a constant shape in a radial direction.