JPH05116139A - Method for cutting hard fragile material by outer peripheral edge - Google Patents

Abstract

PURPOSE:To enhance the accuracy of cutting processing to a large extent by a method wherein a work is sent to the outer periphery of a flexible disc-shaped blade rotating at a constant position while vibration of a low frequency region is imparted to the work in the same direction as the cutting direction of the work or the direction crossing said cutting direction at a right angle to be cut. CONSTITUTION:A work 9 is sent to the outer periphery of a flexible disc-shaped blade 10 rotating at a constant position while vibration of a low frequency region is imparted to the work 9 in the same direction as the cutting direction of the work or the direction crossing the cutting direction at a right angle to be cut. Therefore, cutting and separation are alternately repeated between the outer peripheral edge of the disc-shaped blade 10 and the work 9 by the vibration of the work 9 and cutting resistance is reduced. Even when offset abrasion is generated in the outer peripheral edge, no bending cutting is generated by applying vibration to the work and highly accurate linear cutting becomes possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for cutting a hard and brittle material such as a single crystal ingot or ceramics with an outer peripheral edge of a disk-shaped blade.

[0002]

2. Description of the Related Art As a method of cutting a hard brittle material, a method of cutting with a peripheral blade of a rotating disc-shaped blade and a method of cutting with an inner peripheral blade of a hollow disc-shaped blade are known. The peripheral blade cutting method has drawbacks in that the blade is easily bent due to a cutting reaction force to cause bending, and the blade thickness must be increased, resulting in large material loss and low cutting accuracy. Therefore, at present, the inner peripheral blade cutting method with low material loss and high accuracy is mainly used, and the outer peripheral blade cutting method is used only for roughing such as cutting both ends of the ingot and block cutting.

[0003]

However, the peripheral blade cutting method is characterized in that the structure of the processing device is simple, the operability is good, and the price is low. Therefore, reduce the blade thickness,
If the cutting accuracy can be improved, it is possible to provide a peripheral blade cutting device suitable for cutting a hard brittle material.

An object of the present invention is to provide a peripheral blade cutting method capable of reducing the cutting resistance applied to the blade at the time of cutting to improve the processing accuracy and preventing the bending due to the uneven wear of the cutting edge.

[0005]

According to the method for cutting a work of the present invention, a work 9 is provided on the outer periphery of a disk-shaped blade 10 having flexibility that rotates at a fixed position in the same direction as or orthogonal to the cutting direction. It is characterized by sending and cutting while applying vibration in the low frequency region.

[0006]

In the conventional outer peripheral blade cutting method, since the cutting resistance is large, the outer peripheral blade is made thicker so as to have resistance, but the outer peripheral blade causes uneven wear and cuts the work linearly. It was not possible to do this, and waviness occurred on the cut surface, and the processing accuracy was reduced.

In the method of the present invention, the vibration of the work causes
Cutting and separation are alternately repeated between the outer peripheral blade and the work, and the cutting resistance is reduced. Further, it has been proved by the experimental results that by applying vibration to the work, even if the outer peripheral blade is unevenly worn, the bending does not occur and a highly accurate linear cutting can be performed.

The higher the frequency of vibration applied during cutting and the larger the amplitude, the greater the reduction in cutting resistance. It should be noted that the chips are blown in the ultrasonic range to cause various problems, so it is preferable to keep the chips in the low frequency range.

A vibration cutting method is known as a method for reducing the cutting resistance in the cutting process using a rigid grindstone or a cutting tool. However, there is no known example of using a vibration cutting method for a flexible cutting tool such as a diamond blade, and this also reduces waviness of the machined surface even when the blade is unevenly worn. That is not predictable from vibration cutting with rigid tools.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 6 to 8 show an outer peripheral blade cutting device suitable for carrying out the present invention. In the figure, 1 is a base, 2
Is a fixed base fixed to the upper surface of the base 1, 3 is a first movable base provided on the fixed base 2 so as to be slidable in the front-back direction of FIG. 6, and 4 is a first movable base for setting the position of the first movable base 3. 1 handle, 5 is the first
A second movable base provided on the movable base 3 so as to be slidable in the left-right direction in FIG. 6, 6 is a second handle for setting the position of the second movable base 5, and 7 is a feed to the second movable base 5. A motor for giving, 8 is a vibrating device mounted on the second moving table 5, 9 is a work fixed on the vibrating device 8, 10 is a cutting blade rotatably provided above the work 9, Reference numeral 11 is a spindle of a cutting blade, 12 is a waterproof cover mounted on the second moving table 5 so as to cover the vibrating device 8, the work 9 and the cutting blade 10, and 13 drives the spindle 11 via a gear train (not shown). Motor, 14 is an elevating frame on which the spindle 11 and the motor 13 are mounted, 15 is a third handle for setting the position of the elevating frame,
16 is a machining fluid nozzle that supplies the machining fluid to the cutting blade 10, 17 is a water supply pump that delivers the machining fluid to the machining fluid nozzle 16, 18 is a tank that stores the machining fluid, 19 is a controller of the vibration device, and 20 is It is an operation panel.

Details of the vibration device are shown in FIG. A vibrating table 25 is mounted on a support frame 24 erected on the base 23 so as to be slidable in the left-right direction in the figure, and a processing table 26 for fixing the work 9 is fixed to the upper surface of the vibrating table 25.
The left end of the vibrating table 25 is connected to an eccentric wheel 28 driven by a motor 27 via a crank rod 32, and its right end is connected to a balance weight 30 via a phase inverter 29.
Is linked to. The phase inverter 29 is composed of a rocking lever of equal length on the left and right, which is supported by a vertical fulcrum pin 33 so as to be rockable about its center, and the vibrating table 25 and the balance weight 30 are connected to both ends thereof by connecting links 34 and 35. is doing.

The rotational force of the motor 27 is transmitted to the eccentric wheel 28 via the timing belt 31, and the eccentric center wheel produces an approximate harmonic vibration, which is transmitted to the vibrating table 25. Given. The phase shifter 29 shifts the phase of the vibration of the vibrating table 25 by 180 degrees to vibrate the balance weight 30, thereby preventing the vibration from adversely affecting other members.

Next, the method of the present invention will be described in detail by using the above apparatus.

A soda glass of 50 × 60 × 10 mm is used as the work 9 and a diameter of 125 × 1 is used as the cutting blade 10.
mm, SD # 200 diamond blade was used, the peripheral speed of the diamond blade was set to 1915 mm / min, the soda glass was fed at a feed rate of 20 to 80 mm / min, and cut to a cut amount of 11 mm. The frequency given to soda glass is 0 to 28 Hz, and the amplitude is 0 to
It is 0.6 mm.

The results are shown in FIGS. 1 to 5.

FIG. 1 shows the relationship between the frequency applied to the work and the value of the current flowing through the spindle drive motor 13. As shown in the figure, as the frequency increases, the current value decreases and the cutting resistance decreases. It is considered that when vibration is applied, cutting and separation of the diamond blade with respect to the work alternately occur, and when the frequency is increased, the cycle is shortened and the cutting amount per one cycle of vibration is reduced, so that the cutting resistance is reduced.

FIG. 2 shows the relationship between the amplitude and the current value. As shown in the figure, the current value decreases as the amplitude increases. It is considered that this is because when the amplitude becomes large, the amount of separation of the diamond blade per one cycle of vibration with respect to the workpiece becomes large and the cutting time for one cutting becomes short.
Further, it is considered that when the diamond blade retracts, chips are easily discharged and a grinding liquid is easily introduced, and thus cutting resistance is reduced.

Next, in order to investigate the relationship between the wear of the cutting edge of the blade and the cutting resistance and waviness, a test was carried out using a new blade and a blade having a partially worn cutting edge. Figure 9
Is a diagram showing the cross section of the tip of the processed groove, (a) shows the groove shape when a new blade is used, and (b) shows the groove shape when an unevenly worn blade is used. This groove shape is used for the test. The cross-sectional shape of the blade edge of the existing blade is shown.

FIG. 3 is a diagram showing the relationship between the frequency and the current value of a blade that is unevenly worn. As shown in the figure, the current value of 0.22 A is shown when the blade feed speed is 80 mm / min during the non-vibration cutting, but it decreases to a maximum of 0.10 A when vibration is added. Similarly, at other feed rates, the current value decreased to about 50% at the maximum.

FIG. 4 shows the relationship between frequency and surface waviness.
As shown in the figure, the surface waviness was 5.7 mm with the new blade at the time of non-vibration cutting, while the unevenly worn blade had a large amount of blade deformation in the lateral direction, resulting in a surface waviness of 27 μm. It was Moreover, when vibration was applied to the new blade, the surface waviness tended to slightly decrease. On the other hand, when vibration was applied to the blade that was unevenly worn, the surface waviness was reduced to nearly 14 μm.

FIG. 5 is a diagram showing the relationship between the frequency and the width of the processed groove. Both new blades and partially worn blades reduce the groove width by giving vibration to the work. With the new blade, the kerf loss is slightly reduced when the vibration is applied, whereas with the unevenly worn blade, the kerf loss is increased at the time of vibration-free cutting, but when the vibration is applied, the kerf loss is considerably reduced, and the effect of the vibration is clearly shown. This is because, as the frequency increases, the cutting resistance decreases as shown in FIG. 3, and the load acting on the outer circumference of the blade during cutting decreases, so the lateral bending due to uneven wear of the blade decreases. It is thought to be because of it.

[0022]

As described above, according to the present invention, the cutting resistance applied to the outer peripheral blade can be reduced, the groove width at the time of cutting can be reduced, and the surface waviness at the cutting end face can be reduced. Therefore, if the same processing accuracy is required, it is possible to perform processing using a thinner blade. In particular, when a blade that is unevenly worn is used, the cutting resistance can be reduced to about half and the surface waviness of the cut surface can be significantly reduced, so that the cutting accuracy of the cutting process can be greatly improved.

[Brief description of drawings]

FIG. 1 is a diagram showing a relationship between a frequency and a current consumption of a spindle motor.

FIG. 2 is a diagram showing a relationship between amplitude and current value.

FIG. 3 is a diagram showing a relationship between a frequency and a current value in a plate with uneven wear.

FIG. 4 is a diagram showing a relationship between frequency and surface waviness.

FIG. 5 is a diagram showing a relationship between a frequency and a machining groove width.

FIG. 6 is a front view of a peripheral blade cutting device.

FIG. 7 is a side view of a peripheral blade cutting device.

FIG. 8 is a perspective view of the vibration device.

FIG. 9 is an enlarged cross-sectional view of the tip of the processed groove.

[Explanation of symbols]

 9 Work 10 Cutting blade

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Takehiko Kitagawa, 1-7 Ogigaoka, Nonoichi-cho, Ishikawa-gun Ishikawa Prefecture, Kanazawa Institute of Technology (72) Takahisa Uchida 1-7, Ogaigaoka, Nonoichi-cho, Ishikawa-gun, Kanazawa Institute of Technology

Claims (1)

[Claims] 1. A work (9) is fed to the outer periphery of a flexible disk-shaped blade (10) that rotates in a fixed position while vibrating in a low-frequency region in the same direction or a direction orthogonal to the cutting direction. A method of cutting a hard brittle material with a peripheral blade, which comprises cutting with a peripheral edge.