JP2016159401A - Cutter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin cutter that cuts well.SOLUTION: A diamond cutter 1 includes: a discoid substrate 10 provided with a shaft hole 11 in the center thereof to be connected to an electric power tool; and a tip 20 provided in an outer peripheral part of the substrate 10. The substrate 10 includes: a flat part 14 having the same thickness as that of tip 20 that is continuously formed from the shaft hole 11; and a taper 15 formed in a range from the flat part 14 to the tip 20. The taper 15 is inclined so as to reduce the plate thickness thereof toward the tip 20.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a cutter such as a diamond cutter.

  For example, diamond cutters of type 4 (φ105) to type 8 (φ203) are made by dry methods without water supply, such as concrete buildings, piers, revetments, etc., stone blocks such as concrete blocks, gravestones, stone building materials, tiles, Used for cutting ceramic products such as bricks.

  Here, when the pressing force is constant, the size of the contact area between the diamond cutter and the work (cut object) affects the cutting speed. Naturally, the diamond cutter has a higher cutting speed when the contact area is reduced. For example, the diamond cutter 9 described in Patent Documents 1 and 2 employs a substrate (thin blade substrate) 90 that is thinner than the chip 91 formed on the outer peripheral portion in order to reduce the contact area (see FIG. 8). .

JP 2002-59368 A Japanese Patent Laid-Open No. 7-328928

However, in the above-described conventional technology, since the substrate 90 is thinned according to the chip 91, the strength of the substrate 90 is insufficient. As a result, in the above-described conventional technology, the thrust of the substrate 90 (force to push the substrate 90 in the cutting direction) becomes weak, and the sharpness decreases. On the other hand, when the substrate 90 is thickened, the clearance C is reduced, and the substrate surface (side surface) of the substrate 90 and the workpiece are rubbed and resisted during cutting, and the substrate 90 is heated by frictional heat to cause slipping and thermal cracking. Also decreases.
The clearance C is a difference in thickness between the substrate surface of the substrate 90 and the side surface of the chip 91.

  Then, this invention makes it a subject to provide a cutter with thin and good sharpness.

  In view of the problems described above, a cutter according to the first invention of the present application includes a disk-shaped substrate provided with a shaft hole connected to an electric tool at the center, and a chip provided on an outer peripheral portion of the substrate. The substrate includes a taper that is inclined so that the thickness of the substrate decreases toward the chip.

  According to such a configuration, since the taper is formed on the substrate, the center portion of the substrate can be thickened and the outer peripheral portion of the substrate can be thinned, so that the clearance can be secured while maintaining the strength of the substrate. .

The cutter according to the second invention of the present application includes a flat portion in which the substrate is formed from the shaft hole to a side closer to the shaft hole than a predetermined cutting depth, and the taper formed from the flat portion to the chip. It is characterized by providing.
According to this configuration, the cutter can reduce contact between the substrate surface of the substrate and the workpiece.

In the cutter according to the third invention of the present application, the substrate is formed by providing a flat portion formed from the shaft hole to a side closer to the shaft hole than a predetermined cutting depth, and a step from the flat portion. It is characterized by comprising a thin part thinner than the chip and the taper formed from the thin part to the chip.
According to this configuration, the cutter can reduce contact between the substrate surface of the substrate and the workpiece.

The cutter according to the fourth invention of the present application is characterized in that the taper is formed on one side or both sides of the substrate.
According to this configuration, the cutter can be manufactured by an easy taper process.

According to the present invention, the following excellent effects can be obtained.
Since the cutter according to the first invention of the present application can secure the clearance while maintaining the strength of the substrate, the cutter can be made thin and sharp.

Since the cutter according to the second and third inventions of the present application can reduce the contact between the substrate surface of the substrate and the workpiece at the time of cutting, the sharpness can be further improved and the cutting speed can be increased.
Since the cutter according to the fourth invention of the present application is easy to taper, the manufacturing cost can be reduced.

It is a side view of the diamond cutter which concerns on 1st Embodiment of this invention. It is AA sectional drawing of FIG. It is a partial cross section enlarged view of the diamond cutter of FIG. It is explanatory drawing explaining the usage method of the diamond cutter of FIG. It is a cross-sectional enlarged view of the diamond cutter of FIG. It is sectional drawing of the diamond cutter which concerns on 2nd Embodiment of this invention. It is sectional drawing of the diamond cutter which concerns on 3rd Embodiment of this invention. It is sectional drawing of the diamond cutter which employ | adopted the conventional thin blade board | substrate.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as appropriate. In each embodiment, the same member is denoted by the same reference numeral, and the description thereof is omitted.

(First embodiment)
A diamond cutter (cutter) 1 according to a first embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 1, the diamond cutter 1 cuts a work W (FIG. 4) such as concrete, stone, tile, tile, and the like, and includes a substrate 10 and a chip 20.

The substrate 10 is a thin disc-shaped steel plate, and a shaft hole 11 connected to a spindle 101 of a disc grinder (electric tool) 100 is formed at the center (FIG. 4). Further, the substrate 10 has twelve notches 13 formed in the outer peripheral portion 12 at regular intervals.
Details of the substrate 10 will be described later.

  The chip 20 is formed on the outer peripheral portion 12 of the substrate 10. In the present embodiment, the chip 20 is formed between the notches 13. For example, the chip 20 is a diamond-containing sintered chip obtained by sintering diamond particles.

<Substrate structure>
The structure of the substrate 10 will be described with reference to FIGS. 2 and 3 (see FIG. 1 as appropriate).
As shown in FIG. 2, the substrate 10 includes a flat portion 14 whose both surfaces are flat, and a taper 15 which is inclined so that the plate thickness decreases toward the chip 20.

The flat part 14 is continuously formed from the shaft hole 11 to the side closer to the shaft hole 11 than the cut depth D. In the present embodiment, the flat portion 14 is formed to have the same thickness as the chip 20.
The cutting depth D is the maximum depth at which the diamond cutter 1 can be cut into the workpiece W in the radial direction of the substrate 10 with the tip of the chip 20 as a reference.

  The taper 15 is formed on both surfaces of the substrate 10 such that the substrate 10 becomes thicker on the shaft hole 11 side and the substrate 10 becomes thinner on the outer peripheral portion 12 side. The taper 15 is connected to the flat portion 14 on the shaft hole 11 side, and a chip 20 is formed on the outer peripheral portion 12. As shown in FIG. 3, the taper 15 is inclined by the inclination angle θ with respect to the flat surface (substrate surface) in the flat portion 14.

In the present embodiment, the taper 15 is formed from the side closer to the shaft hole 11 than the cut depth D.
Here, the closer the substrate 10 is to the shaft hole 11, the less the contact between the substrate surface and the workpiece W, and the closer the substrate 10 is to the outer peripheral portion 12, the greater the contact between the substrate surface and the workpiece W. For this reason, the taper 15 may be formed between a flange (not shown) for connection to the disc grinder 100 and the cut depth D.

  For example, it is assumed that the diameter of the diamond cutter 1 is φ105 and the cutting depth D is 25 mm. In this case, the diameter of the substrate 10 is φ91, the diameter of the shaft hole 11 is φ20, and the thickness of the chip 20 is 1.2 mm. Further, the flat portion 14 is formed from the center of the shaft hole 11 to a position of φ50, and the thickness of the flat portion 14 is 1.2 mm. Further, a taper 15 is formed from the position of φ50 to the position of φ91. The taper 15 has a thickness of 0.8 mm at the outer peripheral portion 12 and an inclination angle θ of 0.56 °.

<Usage of diamond cutter>
The usage of the diamond cutter 1 will be described with reference to FIGS. 4 and 5 (see FIG. 2 as appropriate).
As shown in FIG. 4, in the diamond cutter 1, the spindle 101 of the disc grinder 100 is inserted into the connecting shaft hole 11 and fixed by the nut 102. And the workpiece | work W is fixed on a base (not shown), the switch of rotation starting is turned on, and the diamond cutter 1 is rotated. When the cutting edge of the diamond cutter 1 attached to the disc grinder 100 is cut into the workpiece W, the workpiece W is cut by the tip 20 of the diamond cutter 1.

  As shown in FIG. 5, in the diamond cutter 1, the taper 15 is formed to the shaft hole 11 side rather than the cutting depth D, so that the clearance can be maintained at the time of cutting, and the substrate 10 can contact the workpiece W. Few. Thereby, the diamond cutter 1 reduces the frictional resistance received at the time of cutting, and the cutting speed becomes faster. Furthermore, since the diamond cutter 1 reduces heat generation (heat storage), the strength of the substrate 10 can be maintained, and thermal distortion is also reduced, so that accurate cutting along the cutting line is possible.

  Furthermore, since the diamond cutter 1 has a thick shaft hole 11 side and a thin outer peripheral portion 12 side, the strength of the substrate 10 is high and thrust can be maintained. Thus, the diamond cutter 1 can achieve both the thinness of the substrate 10 and good sharpness.

(Second Embodiment)
With reference to FIG. 6, a different point from 1st Embodiment is demonstrated about the diamond cutter 1B which concerns on 2nd Embodiment of this invention (refer FIG. 2 suitably).
This embodiment is different from the first embodiment in that the taper 15B is formed only on one side.

  As shown in FIG. 6, in the diamond cutter 1B, the flat portion 14 is thinner than the chip 20B. The taper 15 </ b> B is formed on one side of the substrate 10 from the side closer to the shaft hole 11 than the cut depth D. The diamond cutter 1B is provided with a clearance C so that the substrate surface on which the taper 15B is not formed does not come into contact with the workpiece W.

  For example, the diameter of the diamond cutter 1B is φ105, and the cutting depth is 25 mm. In this case, the thickness of the chip 20B is 1.4 mm, and the thickness of the flat portion 14 is 1.2 mm. Therefore, the clearance C is 0.2 mm. Further, the taper 15B has a thickness of 0.8 mm at the outer peripheral portion 12 and an inclination angle of 1.12 °.

As described above, the diamond cutter 1B according to the second embodiment of the present invention has the same effects as those of the first embodiment.
Furthermore, since the diamond cutter 1B only needs to form the taper 15B only on one side, the manufacturing is easy and the cost can be reduced.

(Third embodiment)
With reference to FIG. 7, a different point from 1st Embodiment is demonstrated about the diamond cutter 1C which concerns on 3rd Embodiment of this invention (refer FIG. 2 suitably).
The present embodiment is different from the first embodiment in that a thin portion 16 is formed between the flat portion 14 and the taper 15.

  As shown in FIG. 7, the thin portion 16 is formed on both surfaces of the substrate 10 with a step from the flat portion 14. That is, the thin portion 16 is obtained by making the thickness of the substrate 10 one level thinner than the flat portion 14. The thin portion 16 is connected to the flat portion 14 on the shaft hole 11 side, and is connected to the taper 15 on the outer peripheral portion 12 side.

  In the present embodiment, the thin portion 16 is formed from the side closer to the shaft hole 11 than the cut depth D. Furthermore, you may form the thin part 16 from between an above described flange and the cutting depth D. FIG.

  For example, the diameter of the diamond cutter 1C is φ105, and the cut depth D is 25 mm. In this case, the flat portion 14 is formed from the center of the shaft hole 11 to a position of φ40, and the thickness of the flat portion 14 is 1.2 mm. Moreover, the thin part 16 is formed from the position of φ40 to the position of φ60, and the thickness of the thin part 16 is 1.1 mm. Further, a taper 15 is formed from the position of φ60 to the position of φ91. The taper 15 has a thickness of 0.8 mm at the outer peripheral portion 12 and an inclination angle θ of 0.56 °.

As described above, the diamond cutter 1C according to the third embodiment of the present invention has the same effect as that of the first embodiment.
Furthermore, the diamond cutter 1 </ b> C can significantly reduce the contact between the substrate and the workpiece during cutting by forming the thin portion 16. Thereby, the diamond cutter 1C can further improve the sharpness and increase the cutting speed.

(Example)
Hereinafter, the results of the buckling measurement test and the cutting test of the diamond cutter according to the first embodiment of the present invention will be described as examples of the present invention.

As shown in Table 1 below, a buckling measurement test and a cutting test were performed on four types of substrates.
A substrate on which a taper is formed (taper substrate) is referred to as Example 1, and a substrate (quenched taper substrate) obtained by adding a quenching process to Example 1 is referred to as Example 2. The structures and dimensions of the substrates in Examples 1 and 2 are the same as those exemplified in the first embodiment. In Example 2, tempering was performed after quenching at 850 ° C.

Moreover, the buckling measurement test and the cutting test were also performed on the following comparative examples 1 and 2 as comparison objects with the examples 1 and 2.
A substrate (general substrate) having the same plate thickness from the shaft hole to the outer peripheral portion is referred to as Comparative Example 1, and a substrate (thin blade substrate) having a plate thickness smaller than that of Comparative Example 1 is referred to as Comparative Example 2.

In the buckling measurement test, the buckling strength of the substrate was measured. At this time, a universal measuring instrument (AG-25TA) manufactured by Shimadzu Corporation was used as a buckling measuring instrument. Then, with the substrate placed on the buckling measurement jig, the universal measuring instrument was moved 1 mm per 60 seconds to apply a compressive load from the radial direction of the substrate, and the yield point at that time was measured.
The buckling measurement test was performed in a state where no chip was formed on the substrate.

In the cutting test, the speed at which the workpiece was cut with a cutter was measured. At this time, concrete having a nominal strength of 30 N, a width of 100 cm, a length of 30 cm, and a depth of 15 cm was used. The depth of cut was 25 mm in the depth direction. Then, the time required to cut the workpiece 30 cm in the vertical direction was measured. This test was repeated 60 times, and a total of 18 m was cut. Then, the number of seconds required for cutting 30 cm was averaged for 60 times to obtain the cutting time.
The cutting test was performed in a state where chips were formed on the outer peripheral portion of the substrate. Moreover, the chip | tip formed in each board | substrate is the same diamond containing sintering chip | tip.

As shown in Table 1, with respect to Examples 1 and 2 and Comparative Examples 1 and 2, the material to be tested, the outer shape, the substrate thickness, the hardness, the yield point in the buckling measurement test and the yield point ratio, the cutting time in the cutting test showed that.
In Examples 1 and 2, the substrate thickness indicates that the taper tip has a thickness of 0.8 mm and the flat portion has a thickness of 1.2 mm.
The yield point ratio represents the ratio of the yield points of Comparative Example 2 and Examples 1 and 2 with Comparative Example 1 as a reference.

In the buckling measurement test, in each of Examples 1 and 2 and Comparative Examples 1 and 2, the substrate 10 was bent at the tip of the notch.
In Comparative Example 1, the yield point was high because the substrate was the thickest, and the yield point was about twice that of Comparative Example 2. Moreover, since the comparative example 1 had the high thrust of a board | substrate, the cutting time became quick.
In Comparative Example 2, since the substrate was the thinnest, the yield point was the lowest. In Comparative Example 2, the cutting time was delayed because the thrust of the substrate was low.

In Example 1, although the tip of the substrate is as thin as 0.8 mm, the yield point is about 0.9 times that of Comparative Example 1 and about 1.8 times that of Comparative Example 2 due to the taper effect. It became. In Example 1, since the thrust of the substrate was high, the cutting time was also fast.
In Example 2, the hardness was improved by the effect of quenching, and the yield point was higher than in Example 1. In addition, the cutting time of Example 2 was the same as that of Example 1.
As described above, it was found that Examples 1 and 2 can achieve both a thin substrate and good sharpness as compared with Comparative Examples 1 and 2.

(Modification)
As mentioned above, although each embodiment of this invention was explained in full detail, this invention is not limited to above-described embodiment, The design change etc. of the range which does not deviate from the summary of this invention are also included.

  Needless to say, the cutter according to the present invention is not limited to 4 type (φ105) to 8 type (φ203). For example, the cutter according to the present invention may be 4 type or less or 8 type or more.

In the cutter according to the present invention, the thickness of the flat portion is not limited, and may be thinner or thicker than the chip.
The thickness of the tip of the cutter according to the present invention is not limited, and may be 1.4 mm, for example.

The cutter according to the present invention is not limited to the shape of the notch, and may be, for example, a straight shape.
The number of notches in the cutter according to the present invention is not limited, and may be eight, for example. Furthermore, the cutter according to the present invention does not need to form a notch in the substrate.

In the above-described third embodiment, the boundary between the flat portion and the thin portion is formed at a right angle, but the cutter according to the present invention is not limited to this.
For example, the cutter according to the present invention may form a boundary between the flat portion and the thin portion with a taper or a curve. Thereby, since the cutter concerning this invention can suppress the stress concentration to the boundary of a flat part and a thin part, the fatigue strength of a board | substrate can increase and the lifetime of a board | substrate can be extended.

1,1B, 1C Diamond cutter (cutter)
DESCRIPTION OF SYMBOLS 10 Substrate 11 Shaft hole 12 Outer peripheral part 13 Notch 14 Flat part 16 Thin part 15, 15B Taper 20, 20B Chip

Claims (4)

In a cutter comprising a disk-shaped substrate provided with a shaft hole connected to an electric tool in the center, and a chip provided on the outer peripheral portion of the substrate,
The cutter is characterized in that the substrate includes a taper that is inclined so that the plate thickness becomes thinner toward the chip. The substrate is
A flat portion formed from the shaft hole to a side closer to the shaft hole than a predetermined cutting depth;
The cutter according to claim 1, further comprising: the taper formed from the flat portion to the tip. The substrate is
A flat portion formed from the shaft hole to a side closer to the shaft hole than a predetermined cutting depth;
A thin portion formed thinner than the chip, formed with a step from the flat portion,
The cutter according to claim 1, further comprising: the taper formed from the thin portion to the tip.   The cutter according to claim 2 or 3, wherein the taper is formed on one side or both sides of the substrate.

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