JP3165649B2 - Cutting whetstone - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a cutting wheel. More specifically, the present invention relates to a cutting whetstone that generates less noise when cutting stone, concrete, or the like.

[0002]

2. Description of the Related Art Conventionally, when cutting stones, concrete, and the like using a cutting whetstone, noise during operation has been a problem. Therefore, various attempts have been made to develop a cutting whetstone that generates less noise during cutting. For example, Japanese Patent Publication No. 55-500536 proposes a circular saw blade in which an intermediate layer made of copper or a copper alloy is disposed between two steel disks and spot-welded. However, in such a substrate, generation of distortion is inevitable due to a difference in thermal expansion coefficient between the steel plate and the intermediate layer. In addition, when the cutting element is produced by directly sintering the substrate, the steel sheet and the intermediate layer adhere to each other during sintering, and there is a problem that the soundproofing effect is reduced. JP 5
Japanese Patent Application Laid-Open No. 9-107860 proposes a diamond cutter disk in which a plurality of steel sheets are bonded together via an intermediate layer made of a metal or alloy thin sheet having a low Young's modulus, and the steel sheet and the intermediate layer are metallurgically bonded. ing. However, this disk is also distorted due to the difference in the coefficient of thermal expansion between the steel sheet and the intermediate layer, and since the steel sheet and the intermediate layer are metallurgically bonded, the through-hole is formed by using the thin sheet of the intermediate layer as a porous plate. Even if it is drilled, the soundproofing effect does not improve much. In addition,
No. 97652 proposes a substrate structure of a cutting grindstone in which an intermediate plate formed of a copper-based material at the outer periphery and an iron-based material at the inner periphery is disposed between two steel plates and spot-welded. ing. However, such a substrate has a complicated structure, and distortion occurs due to a difference in coefficient of thermal expansion between a copper-based material and another material. Further, Japanese Patent Application Laid-Open No. 8-85066 discloses that a plurality of discs are joined via a separating material such as carbon, boron, and ceramic, and at least one disc is provided with irregularities so that a gap is formed between discs. A superabrasive blade having a contact portion has been proposed. However, such a blade not only requires a pressing step for providing irregularities on the disk, but also makes it difficult to apply a separating material uniformly,
When sintering the superabrasive grains, there is a problem that the separating material is biased and the substrate is partially bonded, and it is difficult to adjust the thickness.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a cutting whetstone which does not generate noise during work and is suitable for cutting concrete, stone and the like.

[0004]

The inventor of the present invention has conducted intensive studies in order to solve the above-mentioned problems, and as a result, bored holes other than at the center of three circular steel plates having different thicknesses. By using a substrate that has been subjected to a treatment that does not fuse to each other on the contact surface and bonded together, it has been found that the noise generated from the cutting grindstone can be significantly reduced, and based on this finding, the present invention has been completed. . That is, the present invention provides (1)
A cutting whetstone having a superabrasive layer on the outer periphery of a substrate obtained by bonding three circular steel plates by spot welding, wherein the thickness of the central steel plate and the two steel plates on both sides are different from each other. The center of the steel plate is covered with a coating selected from chromium, nickel, nickel-chromium, titanium nitride, titanium carbide, and aluminum oxide. (2) a cutting whetstone, characterized in that the surface in contact with the steel plate is coated with a copper film.
A cutting whetstone having a superabrasive layer on the outer periphery of a substrate obtained by bonding three circular steel plates by spot welding, wherein the thickness of the central steel plate and the two steel plates on both sides are different from each other. In addition to the center of the hole is drilled, both sides of the central steel plate is coated with a copper coating, the surface of the two steel plates on both sides in contact with the central steel plate is chromium, nickel, nickel-chrome, titanium nitride, A cutting wheel characterized by being coated with a film selected from titanium carbide and aluminum oxide, and
(3) A cutting whetstone according to the above (1) or (2), wherein the three steel plates are bonded to each other so as to have holes that do not overlap with each other.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The cutting whetstone of the present invention is a substrate in which three circular steel plates are bonded by spot welding, wherein the thickness of the central steel plate and the two steel plates on both sides are different.
Although the thicknesses of the three steel plates can all be different, it is usually advantageous from the viewpoint of workability and the like to make the thicknesses of the two steel plates on both sides the same. The central steel plate and the two steel plates on both sides can be made thicker, for example, the central steel plate can be 0.4 mm and the two steel plates on both sides can be 0.5 mm, or Conversely, the central steel plate may be 0.6 mm and the two steel plates on both sides may be 0.4 mm. By making the thickness of the central steel plate and the thickness of the two steel plates on both sides different, noise generated at the time of cutting is easily absorbed by the substrate. The difference in thickness between the central steel plate and the two steel plates on both sides is preferably 0.02 to 1.0 mm, and more preferably 0.05 to 0.5 mm. The difference in thickness between the central steel plate and the two steel plates on both sides is 0.0
If it is less than 2 mm, a sufficient noise reduction effect may not be obtained. If the thickness difference between the central steel plate and the two steel plates on both sides exceeds 1.0 mm, a sufficient noise reduction effect may not be obtained.

In the cutting wheel of the present invention, the diameters of the three circular steel plates can be the same or different. By making the diameters of the three circular steel plates different from each other, when super-abrasive grain segment chips are directly formed on the outer peripheral portion of the substrate by sintering, the bonding area between the super-abrasive grain segment chips and the substrate increases, This is preferable because the bonding of the abrasive grain segment chips becomes stronger. In the cutting wheel of the present invention, holes are formed in three circular steel plates in addition to the center. There is no particular limitation on the shape of the holes other than the center, but circular holes are easy to machine,
This is preferable because there is no portion where stress concentrates. There is no particular restriction on the position of the holes other than the center, but usually, it is a point symmetrical position with respect to the center of the circular steel plate, and it is necessary that the positions of the holes are equal on the circumference connecting the centers of the holes. It is preferable in maintaining balance, and is also convenient in the case where the holes are stuck together so as not to overlap. The size and number of holes other than the center portion are not particularly limited, and can be appropriately selected within a range where the strength of the substrate of the cutting grindstone can be maintained. By making holes other than the central part of the three steel plates, noise generated at the time of cutting is easily absorbed by the substrate. In addition, since holes other than the central portion have an effect of releasing strain, the work can be stably performed without causing distortion even during sintering or cutting.

[0007] In the cutting wheel of the present invention, both sides of the central steel plate are coated with a coating selected from chromium, nickel, nickel-chromium, titanium nitride, titanium carbide and aluminum oxide. The surface in contact with the steel plate is coated with a copper coating. Alternatively, conversely, both sides of the central steel plate are covered with a copper coating, and the surfaces of the two steel plates on both sides that are in contact with the central steel plate are made of chromium, nickel, nickel-chromium, titanium nitride, titanium carbide, and aluminum oxide. Cover with selected coating. By covering the surface of the steel plate in contact with the surface of the steel plate coated with the copper film with a film selected from chromium, nickel, nickel-chromium, titanium nitride, titanium carbide and aluminum oxide, during sintering of the superabrasive grains Since the surfaces of the steel sheets do not fuse together,
A slight gap is maintained between the steel plates, and the generation of noise during cutting can be suppressed. In the cutting wheel of the present invention, the surface of the steel plate is chromium, nickel, nickel-chrome,
The method of coating with a film selected from titanium nitride, titanium carbide and aluminum oxide is not particularly limited, for example,
Chromium, nickel and nickel-chromium can form a coating by electroplating, electroless plating, etc., and titanium nitride, titanium carbide and aluminum oxide are
Chemical vapor deposition (CV) such as plasma method and high-temperature heating method
D), a film can be formed by a physical vapor deposition method (PVD) such as a vacuum evaporation method or a sputtering method. There is no particular limitation on the method of coating the surface of the steel sheet with the copper film,
For example, electroplating, electroless plating, or the like can be used.

In the cutting whetstone of the present invention, the two steel plates on both sides can obtain a sufficient effect if only the surface in contact with the central steel plate is covered. The steel plate may be coated on both sides.
For example, in the case of coating by plating or the like, it is often easier to apply plating to both surfaces than to mask and remove the masking after masking one surface. In the cutting wheel of the present invention, the thickness of the coating selected from chromium, nickel, nickel-chromium, titanium nitride, titanium carbide, and aluminum oxide coating the steel sheet is not particularly limited, but is preferably 2 to 100 μm. , And more preferably 10 to 50 μm. The thickness of the coating selected from chromium, nickel, nickel-chromium, titanium nitride, titanium carbide and aluminum oxide is 2
If less than μm, chromium, nickel, nickel-chromium, titanium nitride, the surface of the steel sheet coated with a film selected from titanium carbide and aluminum oxide, and the surface of the steel sheet coated with a copper film is a super-abrasive grain There is a possibility that the cutting wheel will not have a sufficient noise prevention effect due to fusion during sintering. The thickness of the coating selected from chromium, nickel, nickel-chromium, titanium nitride, titanium carbide and aluminum oxide is 1
When the thickness is less than 00 μm, a sufficient effect is normally exhibited,
The formation of a coating having a thickness of more than m may result in a loss of time for the material and a loss of economic efficiency.

[0009] In the cutting wheel of the present invention, the thickness of the copper coating on the steel sheet is not particularly limited.
m, more preferably 10 to 50 μm. When the thickness of the copper coating is less than 2 μm,
The surface of the steel sheet coated with copper coating, chromium, nickel,
The surface of the steel sheet coated with a coating selected from nickel-chromium, titanium nitride, titanium carbide and aluminum oxide may be fused during sintering of the superabrasive grains, and the cutting wheel may not have a sufficient noise prevention effect. . Copper coating thickness is 100
When the thickness is less than μm, a sufficient effect is normally exhibited, and the formation of a coating film having a thickness of more than 100 μm may result in a loss of material and time, thereby impairing economic efficiency. In the cutting wheel of the present invention, the thickness of the coating selected from chromium, nickel, nickel-chromium, titanium nitride, titanium carbide, and aluminum oxide and the thickness of the copper coating are significantly smaller than the thickness of the steel sheet. Even if there is a difference in the coefficient of thermal expansion between the steel sheets, there is no possibility that the steel sheets will be distorted.

[0010] In the cutting wheel of the present invention, the central steel plate and the two steel plates on both sides are spot-welded. By superposing three steel plates, sandwiching them between the electrodes, and energizing while applying pressure, the joint can be locally heated and spot-welded in a semi-molten state by resistance heat. There is no particular limitation on the number and position of the spot welding spots, and they can be appropriately selected so that the three steel sheets are integrated and maintain sufficient strength as a substrate of the cutting wheel. When three steel sheets are overlapped and spot-welded, it is preferable to attach the three steel sheets in a state having holes that do not overlap with each other. In addition to the hole in the center, and if necessary, some of the holes in the outer peripheral part overlap and become a penetrating hole, by providing holes that do not overlap each other, compared to the case where all holes overlap, Generation of noise at the time of cutting can be further suppressed. The cutting whetstone of the present invention has a superabrasive grain segment chip on its outer peripheral part. There is no particular limitation on the method of providing superabrasive grain segment chips on the outer peripheral portion. For example, superabrasive grains are directly sintered on the outer peripheral portion of a substrate on which three circular steel plates are laminated to form a superabrasive grain segment chip. It can be formed or a separately made superabrasive segment tip can be bonded to the outer periphery of the substrate. When directly sintering superabrasive grains, the mixture of the superabrasive grains and the binder is compressed into the outer periphery of the substrate using a mold, temporarily formed, and then heated using a sintering furnace. An abrasive segment tip can be formed.

FIG. 1 is a plan view of a circular steel plate used in the present invention. FIG. 1A shows a central steel plate, and FIG.
Are steel plates on both sides, and the diameter of the central steel plate is slightly smaller than that of the steel plates on both sides. In the circular steel plate of this figure, in addition to the hole 1 in the center, eight holes 2 are formed in the outer periphery, and four holes 3 are formed in the middle between the center and the outer periphery. FIG.
FIG. 2 is an explanatory view showing one embodiment of a method for producing a cutting whetstone of the present invention. FIG. 2A is a partial cross-sectional view of the outer peripheral portions of three spot-welded steel plates. In the figure, the central steel plate 4 is smaller in diameter and thinner than the steel plates 5 on both sides. FIG. 2 (b)
FIG. 3 is a partial cross-sectional view showing a state where a mixture of superabrasive grains and a binder is temporarily formed on an outer peripheral portion of a substrate. Since the central steel plate has a smaller diameter than the steel plates on both sides, the area of the joint between the mixture 6 of the superabrasive grains and the binder and the substrate is widened, and a stable and strong bond can be obtained. FIG. 2 (c) shows a substrate obtained by temporarily forming a mixture of the superabrasive grains and the binder of FIG. 2 (b) by sintering using a sintering furnace.
This shows a state in which a superabrasive grain segment tip is formed. By sintering, the mixture of the superabrasive grains and the binder is integrated to form the superabrasive grain segment chip 7, which is firmly bonded to the substrate. FIG.
It is a top view of one mode of the segment type cutting whetstone of the present invention. The substrate on which the three steel plates are bonded is spot-welded in such a manner that holes drilled at portions other than the center of the steel plates do not overlap with each other. Eight superabrasive grain segment chips 7 are formed on the outer peripheral portion.

In the cutting wheel of the present invention, the superabrasive layer at the outer peripheral portion of the substrate can have any shape. FIG.
It is a top view of one mode of a continuous type cutting whetstone of the present invention. In this embodiment, a continuous annular superabrasive layer 8 is formed on the outer peripheral portion of the substrate. FIG. 5 is a plan view of one embodiment of a corrugated cutting wheel of the present invention.
In this embodiment, eleven corrugated superabrasive grain segments 9 are formed on the outer peripheral portion of the substrate. In the cutting wheel of the present invention, the superabrasive grain segment can be formed by any method. For example, the substrate is placed in a mold having an annular cavity, the cavity is filled with a mixture of superabrasives and a binder, preliminarily molded, and then sintered using a sintering furnace. After forming a superannular superabrasive grain layer, the superabrasive layer is subjected to slit processing to obtain a superabrasive grain segment chip. Alternatively, the substrate is placed in a mold having a segment-shaped or corrugated cavity, and the cavity is filled with a mixture of superabrasives and a binder, preliminarily molded, and then sintered using a sintering furnace to obtain a segment type or A corrugated cutting wheel can be obtained. The cutting whetstone according to the present invention is characterized in that the three steel plates are made to have different thicknesses, the steel plates are bonded to each other by making holes in the steel plates so as to have holes that do not overlap each other, and by coating the surface of the steel plates with a coating. Therefore, noise generated when cutting stone, concrete, or the like can be effectively suppressed.

Hereinafter, the present invention will be described in more detail with reference to Examples.
Although described in detail, the present invention is not limited to these examples.
It is not limited. Example 1 A circular carbon steel for machine structural use having a diameter of 94 mm and a thickness of 0.4 mm.
One plate and carbon for machine structure of 96mm in diameter and 0.5mm in thickness
Two circular steel plates were prepared. Center on each steel plate
One hole with a diameter of 20.0mm in the part, radius 2 from the center of the steel plate
4.5mm diameter holes centered on a 5.0mm circumference
Four at intervals, and a circle with a radius of 42.0 mm from the center of the steel plate
Eight equally spaced 5.0mm holes with a center on top
Empty as shown in 1. 94mm diameter steel plate, thickness 10
μm nickel plating, and a further 15
A chrome plating of μm was applied. In addition, a 96 mm diameter steel plate
Two sheets were plated with 30 μm thick copper. Nickel-nick
The chrome-plated steel plate with a diameter of 94 mm is used as the central steel plate.
On both sides with a copper-plated steel plate with a diameter of 96 mm.
Position of the 4.5 mm diameter hole and the 5.0 mm diameter hole
It is shifted by degrees so that they do not overlap.
Welding at 20 points indicated by the mark to obtain a substrate for the cutting wheel
Was. Next, a 40/50 grain size die
5 parts by weight of diamond grains, cobalt, iron, copper and tin
A mixture of 95 parts by weight of the mixed powder is compressed using a mold and temporarily
225 kg / cm using a sintering furnace^TwoPressurization
Sintering at 800 ° C. for 60 minutes to obtain the shape shown in FIG.
Diamond with a thickness of 1.8mm and a depth of abrasive layer of 7.0mm
It has 8 abrasive grain segment chips,
The cut interval is 8.0 mm at the outermost periphery of the segment.
A cutting whetstone was obtained. Using this cutting whetstone, concrete
And cut the noise from the working point.
When measured at a position 1 m away diagonally above 45 degrees, 9
It was 3 dB. Example 2 Three 4.5mm and 5.0mm diameter holes of three steel sheets overlap
Performed except that three steel plates were spot welded in a matched state
A cutting wheel was obtained in the same manner as in Example 1. Using this cutting whetstone
Then, in the same manner as in Example 1,
When the noise was measured, it was 94 dB. Example 3 Instead of applying nickel-chrome plating to the central steel plate,
A coating of titanium nitride was formed to produce a cutting wheel. Implementation
Titanium was added to a 94 mm diameter steel plate with holes as in Example 1.
As a target, a mixed gas of argon and nitrogen (pN_Two=
3 × 10^-Four) As a sputtering gas, and a total sputtering pressure of 1 ×
10^-3Torr, substrate temperature 150 ° C, sputtering voltage 1,00
0 V, cathode current 5 mA, magnetic field 5,000 G, deposition rate
Magnetron sputter under the condition of 1.5μm / h
A titanium nitride film having a thickness of 25 μm was formed. this
The steel sheet coated with the titanium nitride film is
And both sides are made of the same copper-plated steel sheet as in Example 1.
Nipping, substrate of cutting whetstone by spot welding in the same manner as in Example 1
I got Next, a particle size of 40/50 was applied to the outer peripheral portion of the substrate.
5 parts by weight of diamond abrasive, cobalt, iron, copper and
A mixture of 95 parts by weight of the tin powder mixture was poured into an annular cavity.
Tentative molding by compression using a metal mold
225 kg / cm using a furnace ^Two60 minutes at 800 ° C under pressure
During sintering, and the saw thickness is 1.8 mm, as shown in FIG.
7.0mm continuous annular diamond abrasive sintered body
Was formed. Furthermore, the slit interval is
Eight slits are added at equal intervals so that the length is 8.0 mm.
And has eight segment chips of the shape shown in FIG.
A cutting whetstone was obtained. Using this cutting whetstone, concrete
And cut the noise from the working point.
When measured at a position 1 m away diagonally above 45 degrees, 9
It was 3 db. Comparative Example 1 Holes of 4.5 mm in diameter and 5.0 mm in diameter were made in three steel plates.
A cutting wheel was obtained in the same manner as in Example 1 except that there was no
Was. Using this cutting whetstone, the
When the noise at the time of cleat cutting was measured, 96d
b. Comparative Example 2 Except that all three steel plates were 0.5 mm thick,
A cutting wheel was obtained in the same manner as in Example 1. This cutting whetstone
And cut in concrete in the same manner as in Example 1.
When the noise at that time was measured, it was 96 db. Comparative Example 3 Instead of applying nickel-chrome plating to the central steel plate,
Except that all three steel plates were plated with copper
A cutting wheel was obtained in the same manner as in Example 1. Using this cutting whetstone
Then, in the same manner as in Example 1,
When the noise was measured, it was 100 dB. Example 1
Table 3 summarizes the results of Comparative Examples 1 to 3 and Comparative Examples 1 to 3.
You.

[0014]

[Table 1]

The thickness of the central steel plate and the thickness of the steel plates on both sides are different,
The cutting whetstone of Example 1 using a substrate in which a central steel plate is subjected to nickel-chrome plating, a steel plate on both sides is subjected to copper plating, and holes except for the central portions formed in the three steel plates are not overlapped with each other, Low noise when cutting. On the other hand, even if the same steel plate is used, the cutting grindstone of the second embodiment using the substrate in which three steel plates are laminated at a position where the holes other than the center overlap each other has a lower noise than the cutting grindstone of the first embodiment. It can be seen that it is effective to reduce noise by bonding the holes so that the holes other than the center are not overlapped. Also, the thickness of the central steel plate and the steel plates on both sides are different,
The cutting whetstone of Example 3 using a substrate in which the center steel plate is coated with a titanium nitride film, the steel plates on both sides are copper-plated, and the holes except for the center of the three steel plates are non-overlapping, Similar to the cutting wheel of the first embodiment, the noise at the time of cutting concrete is small. The cutting whetstone of Comparative Example 1 using a substrate having no hole except the center portion in the steel plate and the cutting whetstone of Comparative Example 2 using a substrate having all three steel plates having the same thickness were used when cutting concrete. Loud noise. In addition, the cutting whetstone of Comparative Example 3 using a substrate in which all three steel plates are plated with copper has the largest noise when cutting concrete. In the cutting test of the concrete of Example and Comparative Example, the cutting whetstone of the present invention of Example 1
In particular, the noise in the high frequency range of 3,000 Hz or more was remarkably reduced.

[0016]

According to the cutting wheel of the present invention, the thickness of the three steel plates is made different, holes are formed in other than the center of the steel plates, and the coating prevents the fusion of the steel plates. Noise generated when cutting concrete or the like can be effectively suppressed.

[Brief description of the drawings]

FIG. 1 is a plan view of a circular steel plate used in the present invention.

FIG. 2 is an explanatory view showing one embodiment of a method for producing a cutting whetstone of the present invention.

FIG. 3 is a plan view of one embodiment of a segment type cutting wheel of the present invention.

FIG. 4 is a plan view of one embodiment of a continuous-type cutting grindstone of the present invention.

FIG. 5 is a plan view of one embodiment of a corrugated cutting wheel of the present invention.

[Explanation of symbols]

 Reference Signs List 1 center hole 2 hole 3 hole 4 central steel plate 5 steel plate on both sides 6 mixture of superabrasive grains and binder 7 superabrasive grain segment tip 8 annular superabrasive grain layer 9 corrugated superabrasive grain segment

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Claims (3)

(57) [Claims] 1. A cutting whetstone having a superabrasive layer on an outer peripheral portion of a substrate obtained by bonding three circular steel plates by spot welding, wherein the thickness of a central steel plate and two steel plates on both sides are different. , 3
Holes are drilled in addition to the central part of the steel sheets, and both sides of the central steel sheet are covered with a film selected from chromium, nickel, nickel-chromium, titanium nitride, titanium carbide and aluminum oxide. A cutting wheel, characterized in that a surface of the steel plate in contact with the central steel plate is coated with a copper coating. 2. A cutting whetstone having a superabrasive layer on the outer periphery of a substrate obtained by bonding three circular steel plates by spot welding, wherein the thickness of the central steel plate and the two steel plates on both sides are different. , 3
Holes are drilled in addition to the central part of the two steel plates, both sides of the central steel plate are covered with a copper coating, and the surfaces of the two steel plates on both sides that contact the central steel plate are chrome, nickel, nickel-chrome, A cutting wheel characterized by being coated with a film selected from titanium nitride, titanium carbide and aluminum oxide. 3. The cutting whetstone according to claim 1, wherein the three steel plates are bonded to each other with holes that do not overlap each other.