JP2004322233A - Chamfering work method of hard fragile plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for enhancing quality of a work surface without requiring supply of a cutting liquid by restraining a temperature rise in a work point in the chamfering work method of a hard fragile plate suitable for chamfering the cut-and-split edge of a glass pane used for, for example, a liquid crystal panel. <P>SOLUTION: A tool edge 6 is contacted with a ridgeline part of the chamfering edge of the hard fragile plate 1, and the hard fragile plate and the tool edge are relatively moved in the ridgeline direction being the cutting direction of a tool, and ultrasonic vibration is imparted to the tool edge 6. The vibration direction of the ultrasonic vibration is desirably set as circular and elliptic vibration or rocking vibration including the movement in the ridgeline direction for chamfering. When the tool is a rotary tool, the vibration direction can be set in the shaft direction of the tool. Work is performed without using the cutting liquid at all, and a superior result is sometimes provided in case of performing the work in a wetted state by dripping of the cutting liquid on the work point. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for chamfering a sharp ridge line of a side of a hard brittle plate obliquely or in an arc shape, for example, to a method suitable for chamfering a sharp ridge line generated on a cut side of a glass plate used for a liquid crystal panel. It is.
[0002]
[Prior art]
2. Description of the Related Art A liquid crystal panel used as a display device of an electronic device is manufactured by a process of forming a plurality of devices in a matrix on a glass substrate having a predetermined size, and then cutting the device into dimensions for each device. A general method of cutting a glass plate is to use the brittleness of glass. A scribe groove (scratch groove) is formed on the surface of the glass with a diamond point or a roller. Vertical cracks are promoted by heat or impact to break the cracks. A rough ridge line due to scratching or a sharp ridge line due to cracks is formed at the ridge portion of the cut side of the glass substrate cut by such a method. Therefore, it is necessary to chamfer the ridge line portion to prevent the fingertip from being hurt when the operator lifts, and to prevent the ridge line from being chipped or cracked.
[0003]
Conventionally, this chamfering is performed using a rotary grindstone as shown in FIGS. That is, as shown in FIG. 6, the outer periphery of a plurality of disk-shaped grindstones 12 rotating around an axis 11 substantially parallel to the ridge line 2a to be chamfered, and the ridge line 2 of the glass substrate 1 serving as a work. To move the glass substrate 1 relative to the grindstone 12 in the direction of arrow 13 in the figure along the ridgeline. When, for example, three grindstones are mounted on the rotating shaft 11, the cutting is sequentially performed by the three grindstones, and chamfering of the chamfer dimension C is performed on the ridge line portion. The rotation direction of the grindstone 12 is the direction of arrow 14 in the figure from the surface of the glass substrate to the side.
[0004]
[Problems to be solved by the invention]
In chamfering a glass substrate using a conventional grindstone as shown in FIGS. 6 and 7, a cutting fluid is applied to a machining point in order to suppress a rise in temperature at the machining point due to the grinding stone 12 rubbing the machining point at high speed. Supply is indispensable, and as shown in FIG. 7, it is necessary to perform machining while continuously supplying a large amount of cutting fluid from the cutting fluid nozzle 16 toward the machining point 15. That is, in the chamfering of the glass substrate by the grinding wheel, since the heat generated at the processing point is large, the amount of the processing liquid for suppressing the temperature rise by depriving the heat also increases, and the water supply tank having a large capacity or the injected cutting liquid is used. It was necessary to provide a drainage structure and the like for recovery in the device. In particular, when chamfering with a rotating grindstone, the cutting fluid scatters in all directions with the rotation of the grindstone, so a large cover is required to collect the scattered water droplets and mist. The drainage structure becomes large.
[0005]
In addition, in order to improve the machining efficiency of chamfering, it is necessary to increase the rotation speed of the grinding wheel. It becomes impossible to catch up with the rubbing speed, it becomes a state close to dry grinding, the temperature of the processing point sharply rises, and the phenomenon that the quality of the processed surface deteriorates and the life of the grinding wheel decreases, and this is the limit There is a problem that there is a limit in increasing the feed speed of the workpiece and the cutting depth of the grinding wheel.
[0006]
Further, in the grinding of a hard brittle material, there is a problem that chipping or chipping is liable to occur since the grinding is performed by removing the work so as to peel off the work.
[0007]
The present invention has been made in order to solve the above-mentioned problems of the prior art, and it is possible to suppress a rise in the temperature of a processing point as much as possible. It is an object of the present invention to provide a method for chamfering a hard brittle plate such as a glass substrate, which can have a high surface quality.
[0008]
[Means for Solving the Problems]
In the method for chamfering a hard brittle plate according to the invention of the present application, the tool cutting edges 6, 6a, 6b are brought into contact with the ridge of the side to be chamfered of the hard brittle plate 1, as described in claim 1. The above problem is solved by relatively moving the hard brittle plate and the tool edge in the direction of the ridge, which is the cutting direction of the tool, and applying ultrasonic vibration to the tool edges 6, 6a, 6b. .
[0009]
As the vibration direction of the ultrasonic vibration applied to the tool cutting edges 6, 6a, 6b in the above chamfering method, as described in claim 2, vibration including movement in the cutting direction, that is, movement in the ridge line direction to be chamfered, For example, a circular or elliptical vibration or oscillating vibration having the direction as the diameter direction is preferable.
[0010]
In the above-described chamfering method of the present application, as the ultrasonic vibration applied to the tool cutting edges 6, 6a, 6b, the locus of the cutting edges when the tool cutting edges 6, 6a, 6b vibrate is chamfered. It is preferable to use vibration of a circular or elliptical locus or oscillation of a circular arc or elliptical arc locus around an axis in a direction intersecting the ridge line to be tried, typically around an axis in a direction orthogonal to the ridge line.
[0011]
When the rotary tool 10 such as a milling cutter is used as the tool, the vibration direction of the ultrasonic vibration applied to the tool edges 6a and 6b may be set to the rotation axis direction of the rotary tool. It is.
[0012]
The shape of the cutting edge of the tool can conform to the shape of the cutting edge of a general metal cutting tool. Processing can be performed without using any cutting fluid, but performing processing in a wet state, such as by dropping a cutting fluid onto a processing point, can provide good results in some cases. In this case, the amount of cutting fluid is extremely small, and it is not necessary to provide a special drainage structure in the apparatus.
[0013]
The frequency of the ultrasonic wave to be applied is generally 10 to 50 kHz and the amplitude of one side is several tens of microns, but the processing speed can be increased by increasing the frequency. The workpiece feed speed varies depending on the vibration frequency and amplitude of the applied ultrasonic wave, but is a speed of several m to several tens m / min.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, an embodiment of the present invention will be described with reference to the drawings. A glass plate 1 whose chamfered side 2 is to be chamfered is fixed on a table 3, and a tool cutting edge (slow-away tip) 6 attached to a vibration device 4 having a built-in piezoelectric vibrator via a tip holder (horn) 5. , A vibration voltage is applied to the piezoelectric vibrator from the vibration oscillator 7, and the tool edge 6 is moved in the direction of arrow 9 while being vibrated in the direction of arrow 8. Here, the feed direction indicated by an arrow 9 is parallel to the cutting side 2, and the vibration direction 8 of the tool edge is the same as the feed direction 9.
[0015]
The vibration trajectory of the tool edge 6 may be a linear trajectory by a linear reciprocating motion as shown in FIG. 3A, but as shown in FIG. 3B, an arc or an elliptical arc having a velocity component parallel to the feed direction 9 It is preferable to use a locus, and a circular or elliptical locus may be used as shown in FIG. When making a circular or elliptical locus, when the tool cutting edge 6 comes into contact with the workpiece 1, the tool cutting edge 6 is vibrated so as to move in the feed direction.
[0016]
In such vibration cutting, it is necessary that the speed at which the tool edge 6 moves in the retreating direction due to vibration is higher than the feed speed, so that the tool edge 6 intermittently separates from the cutting point of the work, and heat radiation occurs. Is promoted. When supplying the cutting fluid to the cutting point, a cutting fluid dripping nozzle is disposed in front of the tool cutting edge 6 in the feed direction, or the cutting fluid is applied in advance to the ridge portion of the cut side 2 to be chamfered. Means can be adopted.
[0017]
The vibration direction of the vibrating device 4 depends on the direction in which the axis 5a of the tip holder is provided with respect to the ridge line 2a of the work, but is orthogonal to the upper surface 1a of the work as shown in FIGS. When provided in the direction, the vibration shown in FIGS. 3A and 3B can be applied to the cutting edge by bending vibration that bends the shaft 5a in the feed direction or torsional vibration that twists around the axis. it can.
[0018]
1 and 2 show an example in which the upper ridge line of the glass substrate 1 is chamfered obliquely using a triangular tool edge, but it is possible to chamfer in an arc shape by the shape of the tool edge 6. It is also possible to provide the tool cutting edge 6 integrally above and below the glass substrate 1 and to chamfer the upper and lower ridge lines at the same time. In the case of a glass substrate such as a liquid crystal, the chamfer dimension C is about 0.3 to 0.5 mm.
[0019]
4 and 5 are views showing an example using a rotary tool 10 such as an end mill or a reamer. FIG. 4 shows an example of processing with a cutting edge 6a on the end face of the rotary tool 10, and FIG. The example which processes by is shown. In the drawing, an arrow 9 is a feed direction of the work 1 with respect to the tool 10, an arrow 8a, 8b is a vibration direction, and indicates that the tool cutting edges 6a, 6b are vibrated in one or both directions of the arrows 8a, 8b. ing.
[0020]
【The invention's effect】
According to the present invention described above, in the chamfering of a hard brittle plate such as a glass substrate, the cutting resistance is reduced, and the increase in the processing temperature is suppressed. This eliminates the need for a large-scale structure for supplying, discharging, and preventing scattering of the cutting fluid, which is required in the past, and reduces running costs. In addition, since chips are generated in small increments due to the vibration of the tool edge, the chips are less likely to adhere to the tool edge, and tool life and machining surface accuracy can be improved. Further, there is an effect that the feed rate can be improved due to the improvement in machinability by vibration cutting, and the productivity of chamfering hard brittle plates can be improved.
[Brief description of the drawings]
1 is a perspective view schematically showing a chamfering method according to the present invention; FIG. 2 is a schematic enlarged front view of a processing portion in the method shown in FIG. 1; FIG. 3 is a side view showing an example of a vibration locus of a tool edge; FIG. 4 is a perspective view showing an example of machining with a cutting edge on the end face of the rotary tool. FIG. 5 is a perspective view showing an example of machining with a cutting edge on the peripheral surface of the rotary tool. FIG. 6 is a chamfer using a conventional rotary grindstone. FIG. 7 is a perspective view schematically showing a processing method. FIG. 7 is an enlarged front view of a processing portion in the method of FIG.
1 Glass plate 6, 6a, 6b Tool edge 10 Rotary tool

Claims (4)

A tool edge (6, 6a, 6b) is brought into contact with a ridge portion of a side to be chamfered of the hard brittle plate (1), and the hard brittle plate and the tool blade edge are moved in the ridge direction, which is a cutting direction of the tool. A method of chamfering a hard brittle plate, characterized in that ultrasonic vibration is applied to the tool edge (6, 6a, 6b) while being relatively moved along the tool edge. The chamfering method for a hard brittle plate according to claim 1, wherein the vibration direction of the ultrasonic vibration applied to the tool edge (6, 6a, 6b) is the cutting direction. The surface of the hard brittle plate according to claim 1 or 2, wherein the trajectory of the cutting edge when the tool cutting edge (6, 6a, 6b) vibrates is a circular or elliptical locus or an arc or an elliptical arc locus around an axis intersecting the ridge line. Taking method. The chamfering method for a hard brittle plate according to claim 1, wherein the tool is a rotary tool (10), and a vibration direction of the ultrasonic vibration applied to the tool cutting edge (6a, 6b) is a rotation axis direction of the rotary tool. .

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