JPH0258067B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a circular steel substrate 1 as shown in FIG.
A central hole 2 for attachment to the rotating shaft is drilled in the center of the grinding wheel, a large number of slots 3 are formed on the periphery at required intervals, and a diamond grinding wheel body 5 (segment) is placed in the divided circumferential portion 4 between each slot 3. This invention relates to a diamond cutting grindstone that is configured by mounting the diamond cutting grindstone.

This type of diamond cutting grindstone is widely used for cutting stone, concrete, etc., grooving, etc., but it has the disadvantage that the substrate 1 is worn out directly under the segments 5, that is, an undercut occurs. That is, initially, the thickness of the substrate 1 is constant over the entire surface, but as the area directly below the segment wears out, the substrate 1 becomes thinner at the portion 6 that holds the segment 5 as shown in FIG.
As the thickness of the grinding wheel decreases, the grinding wheel breaks down at this point.

As a measure to prevent undercutting, a method is used in which a chip 7 of a wear-resistant material such as cemented carbide is attached to the front side of the slot portion 3 of the substrate in the direction of rotation of the grinding wheel (arrow a), as shown in FIG. As a result, wear 6 directly below the segment is almost suppressed, but
As shown in FIG. 4, wear 9 occurs along the circumference below the lower end 8 of the tip (see FIG. 4), and the problem of undercuts cannot be completely solved.

In recent years, the performance of the diamond grinding wheel body 5 has improved and its life has become longer, so that the wear resistance of the substrate 1 is relatively insufficient and the problem of undercut has emerged.
In particular, the substrate of a grindstone for cutting concrete is thin, whereas the material to be cut, concrete, is highly abrasive, so undercuts appear prominently. The same applies to grindstones for cutting asphalt for road pavement.

SUMMARY OF THE INVENTION An object of the present invention is to provide a diamond cutting wheel that prevents undercuts and can withstand normal use until the segments are exhausted. In order to achieve the above object, the present invention is constructed as follows.

It is clear that substrate wear occurs due to chips generated during the cutting process. The chips flow through a small gap between the cut surface of the material to be cut and the substrate and are discharged, but because the relative speed with the high-speed rotating substrate is high, this wears out the steel substrate. The chips mainly generated at the outermost periphery of the grinding wheel temporarily stay in the slot 3 and then flow out into the gap between the workpiece and the substrate as described above, but since the amount of chips is greatest right below the segment, it is important to avoid cutting in this area. first wears out, creating a wear groove along the outermost periphery of the substrate 1. Once a groove is formed, it becomes a flow path for chips and the flow is concentrated in this groove, so that the groove rapidly develops to the state shown in FIG. 26.

In the cutting wheel shown in FIG. 3, the wear-resistant chip 7 reinforces the substrate and prevents the above-mentioned initial wear, which has the effect of suppressing undercuts directly under the segments. However, since there is no barrier of wear-resistant material at the bottom 10 of the slot, a wear groove develops at this location in a process similar to that described above, resulting in an undercut as shown in the cross-sectional view of FIG.

As described above, undercutting occurs as a result of the flow of chips discharged through the gap between the workpiece and the substrate being concentrated along a circular ring of a constant radius on the substrate. If this concentration is avoided and the flow of chips is dispersed, undercuts will not occur. The diamond cutting grindstone of the present invention realizes this state.

FIG. 5 shows an embodiment of the present invention.
Cemented carbide chips with different lengths 15, 16,
17 are arranged repeatedly. Note that the slots 12, 13, and 14 of the substrate 11 are filled with the cemented carbide chips 1.
The depth corresponds to the length of 5, 16, and 17. These wear-resistant chips protect the board from wear and prevent undercuts directly under the segments, which is the same as the conventional structure shown in Figure 3, but the length of the wear-resistant chips is not constant and differs in three stages. Therefore, the difference is that the depth of the slot is also different.

In the present invention, there is an unavoidable tendency for wear to occur along the circular ring in contact with the bottom of the slot on the board, but this is distributed over three circular rings to avoid concentrating on a certain circular ring. , the degree of concentration is reduced by 1/3, and the width of the concentration channel is practically increased by 3 times, so local wear is greatly suppressed,
Substantially no wear groove formation or undercuts are observed until the diamond wheel segments are exhausted.

As described above, the diamond cutting grindstone of the present invention has no fear of damage due to undercuts, is highly reliable in use, and has a long service life, so it is particularly suitable for cutting concrete, asphalt, etc. This is much more advantageous than the conventional method.

In the embodiment shown in FIG. 5, the length of the wear-resistant chip is in three stages, but the present invention is not limited to this number, and a plurality of stages can be adopted as appropriate depending on the application, usage conditions, etc. Also, in the same embodiment, chip 7
Although cemented carbide was used as the wear-resistant material, it goes without saying that any other suitable wear-resistant material may be used.

[Brief explanation of the drawing]

Figure 1 is a front view of a commonly used diamond cutting wheel, Figure 2 is a sectional view of a portion of the same, and Figure 3 is a front view of a portion of a known diamond cutting wheel with a wear-resistant material attached to the slot. , FIG. 4 is a sectional view of the same as above, and FIG. 5 is a front view of the diamond cutting grindstone according to the present invention. 11... Board, 12, 13, 14... Slot, 1
5, 16, 17...Wear-resistant chip.

Claims (1)

[Claims] 1. Slots are formed on the periphery of the substrate at required intervals, diamonds are attached to the divided circumferential parts formed between the slots, and wear-resistant chips are attached to the slots. Repeatedly placing different lengths on the stage,
A diamond cutting grindstone in which the depth of the slot is also varied in accordance with the length of the wear-resistant chip.