JPH0790467B2 - Diamond blade for cutting - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a cutting diamond blade for cutting,
In particular, the present invention relates to improvement of a cutting diamond blade used for cutting a road paved with asphalt, concrete or the like.

[Prior Art] As a diamond blade for cutting stone or concrete, U.S. Pat. No. 3,028,710 discloses diamond blades as shown in FIGS. 5A to 5D. In the diamond blade disclosed in this US Pat.No. 3,028,710, a plurality of standard bow-shaped diamond tips 22 are fixed to the outer circumference of the steel substrate 21 at equal intervals by a fixing means such as brazing. . This diamond tip 22 has an outer layer 22a, as shown in FIG. 5B.
A base layer 22e containing no diamond abrasive grains is formed in the three layers of 22b and the central layer 22c and the lower portions of these three layers (on the center side of the substrate 21). The concentration of diamond abrasive grains contained in the outer layers 22a and 22b is much higher than that of the diamond abrasive grains contained in the central layer 22c (about 4 times). Therefore, as the cutting work progresses, the central layer 22c is worn more than the outer layers 22a, 22b, the outer peripheral surface 22d of the diamond tip 22 has a concave shape as shown in FIG. 5C, and the cutting of the diamond blade is improved. There is an effect. The outer layers 22a and 22b and the central layer 22c have the same composition of the metal binder (bond) used, and the same grain size of the diamond abrasive grains used.

[Problems to be Solved by the Invention] This type of diamond blade can improve sharpness by making the diamond concentration of the central layer 22c lower than that of the outer layers 22a and 22b, but it is extremely worn by asphalt. When a material having properties is cut, there is a problem that wear of the diamond tip 22 is increased and the life of the diamond blade is shortened. Further, when cutting the asphalt road with this diamond blade, as the cutting work progresses, chips and the like cut by the diamond tip 22 contact and collide with the steel substrate 21 of the diamond blade, as shown in FIG. 5D. As shown, the diamond chip 22 fixed to the steel substrate 21, the substrate portion 21a which is the root portion is worn and thinned, the diamond tip 22 is separated from the substrate 21, the diamond tip 22 is used up Before, there is a problem that the diamond blade itself becomes unusable.

As described above, shortening the life of the diamond blade is very unfavorable for road cutting diamond blades where the life is important.

An object of the present invention is to provide a cutting diamond blade having a three-layer diamond tip consisting of an outer layer and a central layer, which can not only improve the sharpness but also prolong the life of the cutting diamond blade. This standard diamond tip and a special diamond tip, which is wider than the standard diamond tip in the radial direction of the diamond wheel, are fixed to minimize the wear of the outer circumference of the substrate located at the root of the standard diamond tip. At the same time, even if the standard diamond tip is completely worn, it is possible to provide a cutting diamond blade having a longer life which enables the cutting operation to be continued only with the remaining special diamond tip.

[Means for Solving the Problems] In order to solve the above problems, the present inventor has found that in the particle size of the diamond abrasive grains, the diamond concentration, and the metal binder forming the diamond tip, the metal binder is In the same case, even if the diamond concentration is the same, if the abrasive grains are large, the number of grains contained per unit volume will be small and the distance between grains will be long, so that the metal bond The present invention has been accomplished as a result of earnest efforts, focusing on the point that the agent is easily worn and the point on the wear of the root of the diamond tip. That is, the cutting diamond blade of the present invention is a cutting diamond blade in which three layers of diamond chips having outer layers formed on both sides of the central layer are fixed to the outer peripheral surface of the substrate at predetermined intervals, and the diamond chips are: The outer layer is formed of a hard metal binder and diamond abrasive grains, the central layer is formed of a softer metal binder and larger diamond abrasive grains than the outer layer, and the concentration of the diamond abrasive grains is the central layer and The outer layer is also composed of the same diamond tip, and the diamond tip is a standard bow-shaped diamond tip and a special diamond tip wider in the radial direction of the diamond wheel than the standard tip One or two chips are fixed to the substrate. To do.

Further, it is preferable that at least one side surface of the substrate is coated with at least two kinds of colors.

[Operation] When an asphalt road or the like is cut by using the cutting diamond blade configured as described above, a hard metal binder and small diamond abrasive grains are formed in the outer layer of the diamond tip, and the center layer is softer than the outer layer. Even if the outer layer and the central layer have the same diamond concentration, the central layer wears more than the outer layer and the outer peripheral surface of the diamond tip is concave because the metal binder and the larger diamond abrasive are used. And the sharpness of the diamond blade is improved. At the same time, a hard metal binder is used in the outer layer, and the diamond concentration of the central layer is the same as that of the outer layer, which reduces wear on the entire diamond tip and extends the life of the diamond blade. A standard diamond tip and a special diamond tip having a width wider in the radial direction of the diamond wheel than the standard diamond tip, one standard diamond tip or two standard diamond tips per special diamond tip. Even if the standard diamond tip is completely worn, the cutting operation can be continued only with the special diamond tip that is not yet completely worn. Furthermore, if at least two colors are applied to at least one side of the substrate, it is very convenient as a guide due to the difference in color when setting the desired cutting depth by rotating the diamond blade. It can be easily confirmed.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings. The members, arrangements, and the like described below are not intended to limit the present invention and can be variously modified without departing from the spirit of the present invention.

FIG. 1A is a partial front view of a diamond blade for cutting in an embodiment of the present invention, FIG. 1B is a sectional view taken along the line BB in FIG. 1A,
1C is a sectional view taken along the line CC of FIG. 1A, and FIG. 1D is FIG. 1B and 1C.
FIG. 1E is an enlarged sectional view of the diamond tips 2 and 3, and FIG. 1E is an enlarged sectional view of the diamond tips 2 and 3 after a slight use of the diamond blade.

The cutting diamond blade D of the present invention comprises a substrate 1 made of steel, a standard bow-shaped diamond tip 2 and a special diamond tip 3 wider than the standard diamond tip 2.

A plurality of notched grooves 8 are provided at regular intervals on the outer peripheral portion of the steel substrate 1 of this example, and a substrate outer peripheral surface 9 is formed between each notched groove 8 and the substrate outer peripheral surface 9 Is such that the standard diamond tip 2 having the above-mentioned bow shape is joined,
It is processed into an arc shape. Also, diamond tip 3
The outer peripheral surface 10 of the substrate to which is bonded is processed into a linear shape.
The standard diamond tip 2 and the special diamond tip 3 are fixed to the outer peripheral surfaces 9 and 10, respectively, and the ratio of the diamond tips 2 and 3 in this example is 2: 1.
It is fixed at a rate of. As a means for fixing the diamond chips 2 and 3 to the substrate 1, conventionally known brazing, laser welding, electron beam welding or the like is used.

As shown in FIG. 1D, the standard diamond tip 2 is composed of three layers, an outer layer 2a, 2b and a central layer 2c, and the outer layer 2a, 2b is a small diamond abrasive grain 4 and hard grain. The central layer 2c is composed of large diamond abrasive grains 5 and a soft-grained metal binder 7.

The grain size of the smaller diamond abrasive grains 4 in this embodiment is about US mesh 35 to 60, and the grain size of the larger diamond abrasive grains 5 is about US mesh 25 to 40. In addition, "hard eyes" and "soft eyes" in the above metal binders 6,7
Is given in comparison with the case of comparing two kinds of metal binders, and does not necessarily mean a generally bronze-based metal binder. The special diamond tip 3 has a different shape, and is otherwise the same in structure as the standard tip. Further, the thickness t ₂ of the central layer 2c (3c) is set to the outer layers 2a, 2b (3a, 3
It is preferable that the thickness is 3 times or more the thickness t ₁ of b). this is,
As will be described later, the range of the concave portion of the chip outer peripheral surface 2d (3d) is widened to improve the sharpness, and the metal binder 7 of the central layer 2c (3c) is connected to the metal of the outer layers 2a, 2b (3a, 3b). This is because even if it is slightly softer than the binder 6, the wear of the entire chip is reduced.

In order to make the above examples clearer, four types of 12-inch cutting diamond blades shown in Table 1 described below were used to cut the asphalt roads for comparison.

The diamond tips of the cutting diamond blades A to D had the same size, and the cutting diamond blade D also used the special tip 3.

As a result of the comparison between the cutting diamond blades A to C and D, the cutting diamond blade D of the present invention has a shorter cutting time per m than the cutting diamond blades A to C, and has a so-called sharpness and a chip. It has been shown that the amount of wear is very small and the so-called life is much longer.

This is because even if the diamond tip has three layers like the cutting diamond blade C, the concentration of diamond in the central layer 22c is reduced and the thickness is set to about twice the thickness of the outer layers 22a and 22b. However, it is considered that the sharpness is not improved because the range of the concave portion formed by the outer layers 22a and 22b and the central layer 22c formed on the outer peripheral surface of the diamond tip is narrowed. Further, since the central layer 22c has a low diamond concentration, large grains, and a soft metal binder, the wear is increased, and the wear of the diamond tip as a whole is reduced by the conventional cutting diamond blade (A and B). ) Will be almost the same.

On the other hand, in the cutting diamond blade D of the present invention, the central layer 2c (3c) has a diamond concentration of the outer layers 2a, 2b (3).
a, 3b) same as the diamond concentration, central layer 2c (3c)
Thickness t ₂ is 4.4 times the thickness t ₁ of the outer layers 2a, 2b (3a, 3b), the range of the concave part of the chip outer peripheral surface 2d (3d) is wide and the sharpness is improved. Even if the metal binder 7 of the central layer 2c (3c) is slightly softer than the metal binder 6 of the outer layers 2a, 2b (3a, 3b), the wear of the entire tip is considerably less than that of the cutting diamond blade C. It can be judged that it has become.

In order to make the above example clearer, an example was performed in which an asphalt road was cut for 3000 m using the above four types of cutting diamond blades A to D. The results are shown in FIGS. 2A and 2B. In this example, a 2200 rpm self-propelled engine cutter was used as the machine used. The cutting depth was 50 mm.

FIG. 2A is a line graph showing the relationship between cutting distance and cutting time per second (seconds), and FIG. 2B is a diamond tip of cutting diamond blades A to D when cutting an asphalt road 3000 m. It is a bar graph showing the amount of wear (mm).

As can be seen from FIGS. 2A and 2B, the cutting diamond blade D according to the present invention always has a cutting time of about 1 second less than the other cutting diamond blades A to C, and the asphalt road 3000 The amount of diamond tip wear after cutting the meter was also about 2 mm less.

Furthermore, after the above test, it was confirmed that even if the standard diamond tip 2 is completely worn and the state shown in FIG. 3 is reached, it is possible to cut with only the remaining special diamond tip 3. . However, it has also been found that if the ratio of standard diamond tips to one special diamond tip is set to three or more, it is impossible to continue cutting with only the remaining special diamond tips. Therefore, if a special diamond tip is attached for the purpose of minimizing the wear of the substrate outer peripheral part of the standard diamond tip fixing part due to chips, etc., 3 or more standard diamond tips, but special diamond tips 3
If cut only by itself (ie until the special diamond tip is completely worn), a ratio of special diamond tip to standard diamond tip of 1: 2 is preferred.

Further, in order to allow the operator to easily set the cutting depth at the start of the cutting work and to confirm the cutting state during the cutting work, as shown in FIG. It is desirable to alternately paint two types of colors on the surface that will be the outer side when the is attached to the machine. For example, in FIG. 4, white paint (or black paint) is applied to the coating area 11a of the inner portion from a position which enters the inner diameter side by l ₁ from the outer circumference of the cutting diamond blade D, and l ₂ enters the inner diameter side from the outer circumference. By applying red paint to the area 11b, it is very convenient as a guide when rotating the cutting diamond blade D to set the desired cutting depth, and the cutting depth during cutting is also easy. I can confirm. Further, in the above example, two kinds of colors are alternately coated, but three or more kinds of coloring may be applied. In this case,
Needless to say, the distance from the outer circumference of each paint is different.

In the above embodiment, the outer peripheral surface 10 of the substrate on which the special diamond tip is attached is processed into a straight line, but this outer peripheral surface 10 is referred to as the outer peripheral surface 9 when the standard diamond tip is attached. It may be processed in the same or opposite circular arc shape, and a wide special diamond tip whose lower surface has a corresponding circular arc shape may be attached.

[Effects of the Invention] As is clear from the above description, in the diamond tip of the diamond blade for cutting of the present invention, the outer layer is provided with the hard metal binder and the smaller diamond abrasive grains, and the central layer is provided with a smaller diameter than the outer layer. By using a soft metal binder and large diamond abrasive grains, and making the outer layer and the central layer have the same diamond concentration, it is possible to improve the sharpness and prolong the life of the cutting diamond blade. In particular, the standard diamond tip and the special diamond tip that is wider than the standard diamond tip in the radial direction of the diamond wheel are arranged at a ratio of 1: 1 or 2: 1. It is possible to minimize the wear of the outer periphery of the substrate located at the root of the Even if all the tips are completely worn, the cutting work can be continued only with special diamond tips that are not yet completely worn, so the life is longer than the cutting diamond blade consisting of only standard diamond tips. .

Furthermore, by coating at least two kinds of colors on at least one side of the board, the setting of the cutting depth at the start of the cutting work and the confirmation of the cutting depth during the cutting work can be performed by recognizing the color difference. It will be easy.

[Brief description of drawings]

FIG. 1A is a partial front view of a diamond blade for cutting in an embodiment of the present invention, FIG. 1B is a sectional view taken along line BB of FIG. 1A,
FIG. 1C is a sectional view taken along line CC of FIG. 1A, and FIG. 1D is a sectional view of FIG. 1B and FIG.
Fig. 1C is an enlarged view of the diamond tip, Fig. 1E is an enlarged sectional view of the diamond tip after a slight use of a cutting diamond blade, Figs. 2A and 2B are graphs, and Fig. 3 is a standard diamond. Fig. 4 is a partial front view showing a state where all the chips are completely worn. Fig. 4 is a front view of a cutting diamond blade in which two kinds of colors are alternately coated on the side surface of the substrate.
5A to 5D show a conventional example, FIG. 5A is a partial side view, FIG. 5B is a sectional view taken along the line BB of FIG. 5A, and FIG. 5C is a sectional view of a diamond tip in use. 5D is a cross-sectional view taken along the line BB in FIG. 5A of the cutting diamond blade during use. 1 ... Substrate (steel substrate), 2 ... Standard diamond tip, 2a, 2b, 3a, 3b ... Outer layer, 2c, 3c ... Central layer, 3
…… Special diamond tips, A, B, C, D …… Diamond blades for cutting.

Claims (2)

[Claims] 1. A cutting diamond blade in which three layers of diamond tips having outer layers formed on both sides of a central layer are fixed to an outer peripheral surface of a substrate at predetermined intervals, wherein the diamond tip has a hard outer layer. Formed from a metal binder and diamond abrasive, the central layer is formed from a softer metal binder and larger diamond abrasive than the outer layer, and the concentration of the diamond abrasive is the same for both the central layer and the outer layer. The diamond tip is composed of a standard bow-shaped diamond tip and a special diamond tip wider in the radial direction of the diamond wheel than the standard tip.
A diamond blade for cutting, characterized in that one special chip or two standard chips are fixed to the substrate. 2. The cutting diamond plate according to claim 1, wherein at least one side surface of the substrate is coated with at least two kinds of colors.