CN113045194B - Scribing wheel - Google Patents

Abstract

The purpose of the present invention is to provide a scoring wheel capable of improving the strength of an end face while forming a vertical crack of a sufficient depth in a substrate. The scoring wheel (100) is provided with: a plurality of blade parts (101) formed along the outer periphery; a plurality of groove parts (102) are provided between the blade parts (101) adjacent in the circumferential direction and are recessed toward the central axis (L0) side. The angle formed by the edge line of the end of the groove is larger than the angle formed by the edge line of the deepest part of the groove when the groove (102) is observed along the direction parallel to the central axis (L0), and the angle formed by the edge line of the end is larger than 155 degrees.

Description

scoring wheel

Technical field

The present invention relates to a scoring wheel for forming scoring lines on brittle material substrates such as glass substrates.

Background technique

A brittle material substrate such as a glass substrate is divided by a scribing process of forming scribe lines on the surface of the substrate and a breaking process of dividing the substrate along the formed scribe lines. In the scribing process, the scribing wheel moves along a predetermined line while being pressed against the substrate surface. Thereby, the scribing wheel rolls on the surface of the substrate to form scribing lines.

The following Patent Document 1 describes a scoring wheel in which a plurality of grooves are formed at a predetermined pitch on the outer peripheral ridge line. By using the scoring wheel with this structure, vertical cracks can be reliably formed on the substrate immediately after starting to score the substrate, and deep vertical cracks can be formed.

Prior technical documents

patent documents

Patent Document 1: Japanese Patent Application Publication No. 09-188534

Contents of the invention

Invent the problem to be solved

When the scribing wheel having the above structure is used, scribing lines are formed by intermittently forming scratches at predetermined intervals on the surface of the substrate and connecting vertical cracks formed directly under the scratches. Furthermore, it is known that the scoring quality varies due to the shape of the grooves. In order to form deep vertical cracks, it is necessary to make the grooves deeper, but this may cause the end face strength of the divided substrate to decrease.

In view of this problem, an object of the present invention is to provide a scribing wheel capable of improving end surface strength while forming vertical cracks of sufficient depth in a substrate.

Solutions for solving problems

The main aspect of the present invention relates to a scoring wheel for forming scoring lines on a substrate. The scoring wheel of this aspect is provided with a plurality of blades formed along the outer circumference and a plurality of grooves provided between the blades adjacent in the circumferential direction and recessed toward the central axis. Here, when the groove portion is viewed in a direction parallel to the central axis, the angle formed by the ridge line at the end of the groove portion is larger than the angle formed by the ridge line at the deepest portion of the groove portion, The angle formed by the ridge lines of the end portion is greater than 155 degrees.

According to the scoring wheel of this solution, when the scoring wheel rolls on the surface of the substrate, the portion near the blade bites into the substrate and forms scratches on the surface of the substrate. At this time, since the groove portion has the above-mentioned shape, the intervals between scratches formed under low load become narrow, and vertical cracks formed at the scratched locations are easily connected. Furthermore, the angle at the edge of the groove, that is, the boundary between the blade and the groove changes gently, making it difficult to cause damage to the substrate. Therefore, the end surface strength of the divided substrate can be improved.

In the scoring wheel according to this aspect, the groove portion may be formed in a curved shape on both sides of the circumferential direction relative to the deepest portion when viewed in a direction parallel to the central axis. In this way, as the scoring wheel rolls, the groove portion will bite into the substrate smoothly. This allows smooth formation of vertical cracks in the substrate.

Invention effect

As described above, according to the present invention, it is possible to provide a scribing wheel that can improve the end surface strength of divided substrates with a simple structure.

The effects and significance of the present invention will be further clarified by description of the embodiments shown below. However, the embodiment shown below is only an example of implementing the present invention, and the present invention is not limited to the content described in the following embodiment.

Description of drawings

(a) and (b) of FIG. 1 are respectively a side view and a front view schematically showing the scoring wheel according to the embodiment. FIG. 1(c) is an enlarged view showing a part of the outer periphery of the scoring wheel according to the embodiment.

FIG. 2 is a diagram for explaining the shape of the groove portion of the scoring wheel according to the embodiment when viewed in a direction parallel to the central axis.

FIG. 3 is a diagram showing the load in the scoring test using the scoring wheels of Experimental Examples 1 to 6. FIG.

FIG. 4 is a graph showing the end surface strength of the divided substrate in a scoring test using the scoring wheels of Experimental Examples 1 to 6. FIG.

Explanation of reference signs

100…scoring wheel

101…Blade

102…Groove

102a…deepest part.

Detailed ways

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, in each figure, for the sake of convenience, the X-axis, Y-axis, and Z-axis that are orthogonal to each other are noted. The Z-axis is parallel to the central axis of the scoring wheel.

(a) and (b) of FIG. 1 are respectively a side view and a front view schematically showing the structure of the scoring wheel 100 . (c) of FIG. 1 is an enlarged view showing a portion of the outer periphery of the scoring wheel 100 .

The scoring wheel 100 has a disk shape obtained by obliquely cutting both edges of the outer peripheral portion. Two inclined surfaces 100a that are inclined in mutually different directions when viewed from the side are formed on the outer peripheral portion of the scoring wheel 100. The two inclined surfaces 100a intersect to form a plurality of blade portions 101 including ridges, and a groove portion 102 recessed toward the central axis L0 is formed between the blade portions 101 adjacent in the circumferential direction. The lengths of the respective blade portions 101 in the circumferential direction are equal to each other. In addition, the lengths of the groove portions 102 in the circumferential direction are also equal to each other. Therefore, the pitch of the blade portions 101 in the circumferential direction is constant, and the pitch of the groove portions 102 in the circumferential direction is also constant.

The scoring wheel 100 is made of cemented carbide, sintered diamond, single crystal diamond or polycrystalline diamond. A circular hole 100b into which a shaft serving as a rotation axis is inserted is formed in the center of the scoring wheel 100. The diameter of the scoring wheel 100 is about 1 mm to 5 mm, and the thickness is about 0.4 to 1 mm. In addition, the angle of the blade portion 101, that is, the angle formed by the two inclined surfaces 100a, is approximately 100 to 160°, and the diameter of the hole 100b is approximately 0.4 to 1.5 mm.

The pitch p1 of the groove portions 102 (the sum of the circumferential length (L1) of one groove portion 102 and the circumferential length (L2) of one blade portion 101) is, for example, approximately 10 to 100 μm. The depth d1 of the groove (the difference in distance between the ridge line of the blade portion 101 and the deepest part of the groove portion 102 in the radial direction of the scoring wheel 100 ) is, for example, about 1 to 10 μm. The length of the area of the scoring wheel 100 that is recessed from the ridge line of the outer peripheral blade portion 101 , that is, the circumferential length (L1) of the groove portion 102 is, for example, approximately 3 to 40 μm. In addition, the same ridge line as that of the blade portion 101 is formed inside the groove portion 102 .

FIG. 2 is a diagram for explaining the shape of the groove portion 102 of the scoring wheel 100 when viewed in a direction parallel to the central axis L0.

As shown in FIG. 2 , a groove portion 102 having a width W in the circumferential direction is formed between adjacent blade portions 101 . When the groove portion 102 is viewed in a direction parallel to the central axis L0 (Z-axis direction), both circumferential side portions relative to the deepest portion 102a have a shape that bulges in a direction away from the central axis L0. That is, the angle at which the ridge lines at the boundary positions P3 and P4 of the blade portion 101 and the groove portion 102 intersect, that is, the end groove angle, is different from the angle between the ridge lines of the groove portion 102 in the deepest portion 102 a , that is, the bottom groove angle. , and the end groove angle is larger than the bottom groove angle. Here, the angle formed by the ridge line of the groove portion 102 and the ridge line of the blade portion 101 changes at positions P1 and P2 on both sides in the circumferential direction with respect to the deepest portion 102 a. It should be noted that in FIG. 2 , for convenience of explanation, the blade portion 101 and the groove portion 102 are shaped as straight lines, but they are actually shapes including curves.

Tangents Ln1 and Ln2 at the ends of the groove 102 are set at boundary positions P3 and P4 between the groove 102 and the blade 101 , and the angle formed by the tangents Ln1 and Ln2 is defined as the end groove angle θ1 . In addition, tangent lines Ln3 and Ln4 are set at both sides of the deepest portion 102a, and the angle formed by the tangent lines Ln3 and Ln4 is set as the bottom groove angle θ2. In this embodiment, θ1 is larger than θ2. In addition, θ1 is 155 degrees or more, preferably 160 degrees or more, and more preferably 165 degrees or more. Accordingly, the deepest portion 102a is located closer to the central axis side of the scribing wheel than the intersection point of the tangent lines Ln1 and Ln2.

As described above, in the scoring wheel 100 , if the angle formed by the tangent to the groove at the boundary between the blade 101 and the groove 102 , that is, the end groove angle θ1 is 155 degrees or more, then the scoring wheel 100 will have a larger scoring load. When the thickness is small, the volume of the portion that bites into the substrate increases, and the distance between the portions that bite into the substrate becomes narrower. This makes vertical cracks more likely to occur under low loads. In addition, since the angle between the blade 101 and the groove 102 at the boundary positions P3 and P4 of the blade 101 and the groove 102 is further blunted, the impact on the substrate can be further reduced and can be compared with the scribing load. Small conditions interact to improve the end face strength of the divided substrate.

In addition, since the bottom groove angle θ2 at the bottom of the groove is smaller than the end groove angle θ1, the groove depth d1 and the groove width can be independently changed according to the type and thickness of the substrate.

<Experimental example>

The inventors conducted scoring evaluation using the scoring wheels 100 of Experimental Examples 1 to 6 obtained by changing the groove end angle θ1 in six steps. As a brittle material substrate, a glass substrate with a thickness of 0.4 mm was used. The scribing speed is set to 100mm/second. The structures other than the shape of the groove portion 102 when viewed in the direction of the central axis L0 are the same in the scoring wheels of Experimental Examples 1 to 6. It is assumed that the outer diameter is 2.0 mm, the thickness is 0.65 mm, and the blade edge angle is 115 Spend.

Fig. 3 is a table related to the scoring wheels of Experimental Examples 1 to 6. As shown in FIG. 3 , the end groove angle θ1 of the scoring wheel 100 is 165.2 degrees in Experimental Example 1, 162.7 degrees in Experimental Example 2, 157.8 degrees in Experimental Example 3, and 154.0 in Experimental Example 4. The temperature was 153.4 degrees in Experimental Example 5 and 150.0 degrees in Experimental Example 6. Using these scribing wheels, it is possible to form rib-like patterns on the substrate by changing the load each time a scribing line is formed, and to confirm a load range with good scribing quality.

As shown in FIG. 3 , in Experimental Examples 1 to 6, the minimum load required to form ribs is 5.0 to 6.5 N, and the larger the groove end angle θ1 is, the smaller the minimum load tends to be. The highest load that can produce a good-quality scribed line is 14.5 to 15.0 N, and the change caused by the groove end angle θ1 is smaller than the lowest load.

Next, each scoring wheel was used to form a scoring line at a load 0.5 N higher than the lowest load shown in Figure 3, and the end surface strength of 20 divided test pieces was measured using a four-point bending test.

FIG. 4 is a graph showing the end surface strength of the divided substrate in a scoring test using the scoring wheels of Experimental Examples 1 to 6. FIG. In FIG. 4 , the average value of the end surface strength is shown by numerical values, and the maximum value and the minimum value are shown by horizontal bars. The lower bar graph represents the standard deviation. As shown in FIG. 4 , the average value of the end surface strength was 121.0N in the scoring wheel of Experimental Example 1 and 110.0N in the scoring wheel of Experimental Example 2. In addition, in the scoring wheels of Experimental Examples 1 and 2, the minimum value of the end surface strength also exceeded 100N, and a tendency for the standard deviation to be relatively low was also found. On the other hand, in the scoring wheel of Experimental Example 3, the average value of the end surface strength was 89.5N, which was a sufficiently high value. In contrast, the end face strengths of the scoring wheels of Experimental Examples 4, 5, and 6 were 73.3N, 53.0N, and 51.3N, respectively.

In this way, it was confirmed that by using the scribing wheel 100 with the end groove angle θ1 of 155 degrees or more, the end surface strength of the substrate after being divided at a load near the minimum load that can form a scribe line can be significantly improved compared to the conventional method. . Thus, by using the scoring wheel 100 of the embodiment, it was confirmed that a good scoring line can be formed even with a lower load.

<Example of change>

In addition to the above, various modifications can be made to the embodiment of the present invention.

For example, in the above embodiment, as shown in FIG. 2 , both sides of the deepest portion 102 a have a shape including a straight portion when viewed in a direction parallel to the central axis L0 , but the shape of the portion is not limited to this. , as long as it protrudes in a direction away from the central axis L0, it can be changed appropriately. For example, the shape of both sides of the deepest part 102a may be a curved shape in which the curvature changes toward the deepest part 102a.

In addition, the length of the ridge line of the blade portion 101 in the circumferential direction can be appropriately adjusted according to the number of groove portions 102 formed on the outer periphery of the scoring wheel 100 . Similarly, the width W of the groove portion 102 in the circumferential direction can also be appropriately adjusted according to the number of groove portions 102 formed on the outer periphery of the scoring wheel 100 .

In addition, in the above-described embodiment, the shape of the groove portion 102 when viewed in the circumferential direction is a shape having ridges inside the groove portion 102 as shown in FIGS. 1(b) and (c) , but it may also be a curved surface shape convex in a direction away from the central axis, a shape including a plane perpendicular to the radial direction, or other shapes.

In addition, the embodiment of the present invention can be appropriately modified in various ways within the scope of the technical idea represented by the technical claims.

Claims (1)

1. A scoring wheel used to form scoring lines on a substrate, The scoring wheel is characterized by: A plurality of cutting edges formed along the outer periphery and containing ridges; and A plurality of groove portions provided between the circumferentially adjacent blade portions and recessed toward the central axis, A ridge is formed inside the groove, When viewed in a direction parallel to the central axis, the angle formed by the ridge line at the end of the groove is larger than the angle formed by the ridge at the deepest part of the groove, and the ridge at the end The angle formed by the lines is greater than 155 degrees, When the groove portion is viewed in a direction parallel to the central axis, portions on both sides of the circumferential direction relative to the deepest portion have a curved shape.