JP3028320B2 - Cutting wheel and its manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to a cutting wheel, and more particularly, to a non-clogging wheel having irregularities on its side surfaces and having a portion having a large and a small grain density.

[0002]

2. Description of the Related Art Conventional grinding wheels, such as cutting wheels and flat wheels,
It is manufactured by compressing abrasive grains made of silicon carbide, gold sand, or the like into a disk shape together with a binder, and then heat-treating the binder. Depending on the use of the grinding wheel, abrasive grains of various particle sizes are appropriately compounded, and a binder made of a liquid or powdery phenol resin or the like is added thereto. As shown in FIG. 1, a disc-shaped lower mold 2 is fitted to the bottom of a cylinder 1, abrasive grains 3 are evenly put on the lower mold 2, a disc-shaped upper mold 4 is fitted, and a hydraulic press is performed. After pressing to form a uniform disk shape as a whole, baking is performed. At the time of this molding, pressing is performed with a reinforcing cloth made of glass fiber or the like sandwiched between both surfaces or an intermediate layer of the disk.

[0003] The above-mentioned conventional grinding wheels often cause clogging when cutting or cutting metal or the like, resulting in poor sharpness.
Further, there has been a problem that the temperature of the grindstone and the cut material becomes high due to frictional heat, and the life of the grindstone is shortened. Especially aluminum,
When grinding a soft metal such as brass, clogging is severe, and it is often necessary to perform dressing. In the case of cutting stainless steel, there is a possibility that the cut material becomes hot and discolors.

Japanese Patent Application Laid-Open No. 49-132688 discloses a relatively hard sector-shaped grinding member having a small pore volume (porosity).
It has been proposed to arrange a grinding wheel by alternately arranging relatively soft sector grinding members having a large pore volume (porosity) to prevent clogging of the grinding wheel and increase grinding efficiency. The grinding wheel in which the relatively small porosity relatively hard sector grinding member and the relatively large porosity relatively soft sector grinding member are arranged alternately separates the soft and hard sector grinding members separately from the abrasive grains. After molding and firing to produce segments, these are alternately arranged and assembled into a disk shape by bonding or the like to each other.The manufacturing process is extremely complicated, and the adhesive strength of the fan-shaped segments is high. It was weak, and there was a possibility that the segments of the grinding wheel would chip or break during the grinding operation.

Therefore, the present inventor has disclosed Japanese Patent Publication No. 3-67834.
When a grinding wheel is molded by a mold as shown in FIG. 1, abrasive grains 3 are evenly placed on a lower mold 2 in a cylinder 1 in FIG. 1 to form an abrasive grain layer having a constant depth. Pressing a disk-shaped pressing die 17 having a fan-shaped uneven portion on the lower surface as shown in FIG. 2 to form the unevenness on the upper surface of the abrasive layer, then removing the pressing die 17 and having a flat lower surface instead When the disc-shaped upper mold 4 is placed and pressed, in the state where the irregularities are formed, the convex portion of the abrasive layer has a large thickness of the abrasive layer, and the concave portion has a small thickness. When pressed, the convex part of the abrasive layer has a large compression ratio and a high abrasive density,
The part that was the concave part of the abrasive layer has a low compression ratio and a low abrasive density, and it is possible to simultaneously mold a grinding wheel where sector parts with large abrasive density and small sector parts are alternately arranged. Indicated.

[0006] However, it is quite difficult for the grinding wheel to form irregularities on the surface of the abrasive layer in the mold during the manufacturing process. That is, after pressing a disk-shaped pressing die having a fan-shaped uneven portion on the lower surface of the abrasive layer on the lower surface to form the unevenness on the upper surface of the abrasive layer, the abrasive particles are sharply applied to the grinding wheel in a fan shape when pressed. In order to cause a difference in density, it is necessary that both the concave portion and the convex portion have an abrasive grain density as uniform as possible in a state where the unevenness is formed on the upper surface of the abrasive grain layer. Only by doing so, the thick protrusions of the abrasive grain layer are pressed into a disk shape having the same thickness as the thin recesses of the abrasive grain layer, resulting in a difference in the abrasive grain density. When the pressing die is pressed to form irregularities on the upper surface of the abrasive layer, in order to make the abrasive density as uniform as possible in the concave portions and the convex portions, the adhesiveness of the abrasive particles mixed with a binder is small, Abrasive grains need to be powders that flow easily. On the other hand, when pressing the abrasive layer having the irregularities on the upper surface with the flat upper mold 4, it is necessary to compress the irregularities formed on the upper surface of the abrasive layer as much as possible, and compress it downward as it is. For this purpose, it is desirable that the abrasive grains be a powder that is slightly sticky and hardly flows. It is difficult to meet conflicting requirements for the fluidity of this abrasive,
When pressed with the flat upper mold 4, a part of the uneven shape on the upper surface of the abrasive layer, the end of the convex portion is easily collapsed, and the difference in the abrasive density is separated by a clear boundary between each part of the formed grinding wheel. Difficult to cause.

Therefore, the present inventor has filed Japanese Patent Application No. Hei 3-225056.
No., when manufacturing an offset-type grinding wheel, uniformly mix compounded abrasive particles with relatively low fluidity in a cylindrical mold, and press a die having an uneven shape on the lower surface on the abrasive layer. When pressed, the pressing die is pressed as it is as the upper die for pressing 4. When pressing, the abrasive grains do not move in the horizontal direction but are compressed in the vertical direction as they are, so the thickness of the finally formed grinding wheel is The thinner the area, the higher the compression ratio of the abrasive grains and the higher the abrasive density, and the thicker the grinding wheel, the lower the compressibility of the abrasive grains and the lower the abrasive density. This method is easy to manufacture a grinding wheel, and the offset type grinding wheel manufactured in this way is extremely unlikely to cause clogging and has a high cutting speed. It was disclosed that.

Further, the inventor of the present invention has disclosed in Japanese Patent Application No. 6-280062 that the cutting surface of an offset grinding wheel has corrugated irregularities, and the corrugations are numerous from the center to the outer periphery of the grinding wheel. The wave front line extends in a substantially radial direction, and the shape of the grinding wheel surface in a cross section along a concentric circle concentric with the center of the grinding wheel is a wavy shape. Disclosed is an offset grinding wheel in which the abrasive density is small and the abrasive density inside the grinding wheel in the concave portion of the waveform is large.

The above-described offset type grinding wheel is designed to efficiently cut a rotating disk grindstone by bringing a circular cutting surface having irregularities into contact with a workpiece. On the other hand, the cutting wheel is used for cutting and cutting by sliding the circumferential surface of the rotating disk wheel on the workpiece, but all the conventional cutting wheels are flat disk wheels, Has no irregularities at all.

[0010]

The conventional grinding wheel tends to be clogged when cutting soft metals such as brass and aluminum, and the cutting speed is slow when cutting stainless steel and the like. If the load at the time of cutting is excessively applied to increase the cutting speed, the grinding wheel is severely damaged and wear due to frictional heat is severe, which is extremely dangerous for the operator. SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a cutting wheel having excellent sharpness and a long service life, in which a circumferential surface of a rotating disk wheel is brought into contact with a workpiece to efficiently cut the wheel.

[0011]

In order to achieve the above object,
The inventor of the present invention has conducted intensive studies, and as a result, by providing irregularities on the circular side surface of the cutting wheel made of a rotating disk wheel, and providing a difference in density between the abrasive grains inside the cutting wheel, the sharpness is extremely excellent. Good cutting efficiency, no clogging,
The present inventors have found that a long-life cutting wheel can be obtained, and have completed the present invention.

That is, according to the present invention, an abrasive grain composition obtained by blending abrasive grains with a binder and the like is compression-molded into a disc shape together with at least one reinforcing cloth made of glass fiber or the like, and then fired. In the cutting wheel, irregularities are provided on both surfaces of the cutting wheel, and the wave height of the corrugations of the irregularities is 7 mm, which is the maximum thickness of the cutting wheel.
In the range of about 30%, the unevenness on both surfaces of the cutting wheel is formed so as to be symmetrical to each other, the abrasive density inside the convex portion of the unevenness is small, and the abrasive density inside the concave portion The gist of the present invention is to provide a cutting wheel in which the whole of the cutting wheel is integrally formed so as to increase the size of the wheel.

In another aspect of the present invention, an abrasive powder obtained by mixing a binder between an upper mold and a lower mold in a cylinder installed with a disc-shaped lower mold fitted to the bottom and having an axis line extending vertically is used. In a method of manufacturing a grinding wheel in which a disc-shaped molded product is heated and fired after pressing into a disc shape by pressing at a high pressure with an abrasive grain composition formed therebetween, the lower mold upper surface having irregularities on the upper surface in the cylinder An abrasive compound is deposited to a certain thickness to form an abrasive layer, and an upper mold having irregularities on the lower surface is placed on the abrasive layer and press-molded, and both surfaces are mutually symmetrical irregularities. By forming a distribution of the abrasive grain density from a high abrasive grain density part to a low abrasive grain density part in a cutting wheel by molding into a disk shape having a grinding wheel. Make a summary.

Next, the contents of the present invention will be described in detail with reference to the drawings. FIG. 3 is a plan view of a cutting wheel of an example of the grinding wheel of the present invention, FIG. 4 is a sectional view of the AOA, and FIG. 5 is a sectional view along the arc BB. Numeral 5 denotes a cutting wheel, on the side surface 9 of which are alternately provided elongated and fan-shaped convex portions 7 and concave portions 8 extending radially. The convex portion 7 and the concave portion 8 are provided on both surfaces of the cutting wheel 5 in a plane-symmetrical manner.

[0015] The cutting wheel 5 of the present invention is prepared by the method described later.
Is manufactured, the abrasive grain density inside the convex portion 7 is small, and the internal abrasive grain density inside the concave portion 8 is large, so that a portion having a large abrasive density and a portion having a small abrasive density alternately cut a workpiece during rotary cutting. Become.

The shapes and arrangements of the concave portions 8 and the convex portions 7 on the side surface 9 of the cutting wheel 5 are not limited to those shown in FIG. 3, but various shapes and arrangements are possible. The conditions necessary for the arrangement are such that, of the concentric circles centered on the rotation axis of the cutting wheel 5, the convex portions 7 and the concave portions 8 are alternately arranged at an appropriate ratio on all concentric circles within the range used for cutting. Need to be On a certain concentric circle, it is not preferable that only the convex portion 7 or only the concave portion 8 is arranged over the entire circumference of the concentric circle. When the grinding wheel 5 is worn down to the concentric circle, it is cut only by the convex portion 7 or the concave portion 8, and the cutting is performed by the peripheral edge of the cutting wheel 5 having a constant width and a constant abrasive grain density. This is because the state is the same as that of the usual cutting by the conventional grinding wheel 5.

Other examples of the shapes and arrangements of the concave portions 8 and the convex portions 7 are shown in FIGS. 6 and 7, for example. In FIG. 6, a large number of convex portions 7 are present in the form of islands in the concave portion 8 of the side surface 9. In FIG. 6, the concave portion 8 becomes the convex portion 7, the convex portion 7 becomes the concave portion 8, and the convex portion 7 and the concave portion 8 are formed.
May be the reverse arrangement of FIG. FIG. 7 shows a radial grid pattern of projections 7 on each part defined by concentric circles and radially extending lines.
And a concave portion 8 (only a part of the concave portion 8 and the convex portion 7 is shown in FIG. 7).

The wave 10 of the cross-sectional shape of the irregularities on the side surface 9 of the cutting wheel 5 is not limited to the rectangular wave shown in FIG. 5, but the sawtooth wave shown in FIG. 8, the triangular wave shown in FIG.
Any shape such as a trapezoidal wave shape shown in FIG. 11 and a substantially sinusoidal wave shape shown in FIG. 11 is possible.

Radially concave portions 8 and convex portions 7 as shown in FIG.
Is provided, the number of waves 10 in the cross section of the concentric circle is not particularly limited, but a wave number of 10 to 100 is used depending on the diameter of the grinding wheel and the purpose of use. For example, for a cutting wheel 5 having a diameter of 100 mm, a wave number of 15 to 50 is preferably used. The thickness of the grinding wheel 5 at the convex portion 7 and the concave portion 8 is not particularly limited. For example, when unevenness is provided symmetrically on both surfaces of the grinding wheel, the thickness of the grinding wheel at the convex portion 7 (the The maximum thickness D is 1.5 to 4.0 mm, the thickness d of the grinding wheel of the recess 8 is 0.7 to 3.0 mm, and the ratio d / D.
Can be set to 0.3 to 0.7. Wave height h of wave 10
Is preferably 5 to 35%, more preferably 7 to 30%, even more preferably 10 to 25% of the thickness D of the convex portion 7 of the cutting wheel 5. When the wave height h is less than 5% of D, the difference between the abrasive grain density inside the concave portion 8 and the abrasive grain density in the portion other than the concave portion 8 becomes small, and the effect of preventing clogging and improving the cutting speed decreases. If the wave height h is greater than 35% of D, the compression ratio of the convex portion 9 of the grinding wheel is small because the bottom of the concave portion 7 cannot be further compressed when the bottom of the concave portion 7 is compressed to a certain abrasive grain density during press molding of the grinding wheel. The strength of the grinding wheel at that portion decreases, and the strength of the entire grinding wheel decreases. The area ratio between the concave portion 8 and the convex portion 7 is not particularly limited, but for example, 0.2 to 0.8 is selected.
0.4 to 0.6 is preferably used.

The wave height h does not need to be constant for all waves, and the wave height h can be changed by the waves. In particular, as shown in the cross-sectional view of FIG. 12 along the concentric arc, large, medium, and small waves with a wave height h can be repeatedly and cyclically arranged in that order.

In order to manufacture the grinding wheel of the present invention, for example, in the case of the cutting wheel 5 shown in FIGS. 3 to 5, a mold comprising a cylinder 1, a lower die 2 and an upper die 4 as shown in FIG. 11 is used. The center of the upper mold 4 and the lower mold 2 has a center hole 13 through which the pin 12 is inserted, respectively, and a wave for forming a rectangular wave wave 10 radially on the lower surface of the upper mold 4 and the upper surface of the lower mold 2. It has a mold 14.

The lower die 2 is fitted to the bottom of the cylinder 1 of the die 11, and an abrasive grain composition 15 described later is thinly put on the lower die 2, and the whole is leveled to a certain depth. A reinforcing cloth 16 made of glass fiber or the like is placed thereon, and the abrasive compound 15 is further put into a certain depth, and the upper part is pressed by the upper mold 4 and pressurized by a hydraulic press. If necessary, another reinforcing cloth 16 made of glass fiber or the like may be pressed in the middle of the abrasive layer. The reinforcing cloth 16 may be provided on both upper and lower surfaces of the abrasive layer 18.

Known abrasive grains for grinding wheels such as silicon carbide, alumina, zirconia, and fine sand can be used as abrasive grains used in the production of the grinding wheel of the present invention. Also, diamond abrasive grains can be partially mixed and used. The abrasive grains are mixed with a liquid phenol resin such as resol type or benzylic ether type and a powdery phenol resin as a binder to form an abrasive grain composition 23. The mixing ratio of the binder is preferably 10 to 30 parts by weight with respect to 100 parts by weight of the abrasive grains.
~ 25 parts by weight is more preferred. The fluidity of the abrasive composition can be appropriately adjusted by adjusting the ratio and the amount of the liquid phenol resin and the powdery phenol resin. In order to manufacture a grinding wheel by the method of the present invention, it is necessary to adjust the fluidity of the abrasive composition to an appropriate fluidity. In a state in which the abrasive composition 15 has a large fluidity and flows smoothly, when the abrasive layer is pressed by the upper mold 4 having the corrugation 14 on the lower surface, the portion of the abrasive that falls under the convex portion of the corrugation 14 Grain 3
Move easily in the horizontal direction, and it is not possible to mold the grain density in that portion sufficiently high. If the fluidity is poor, the pressing pressure will not be evenly transmitted to the inside of the grinding wheel, making it difficult to press uniformly in the direction perpendicular to the surface (in the direction parallel to the surface of the grinding wheel, Naturally, they are not equal, because they produce high and low parts.) It is desirable that the abrasive composition 15 has a shape-retaining property such that it can be slightly shaped when it is firmly gripped by hand.

The abrasive composition 15 may further contain an organic solvent or other liquid fluidity modifier. In addition, additives such as powdered fillers such as cryolite, calcium carbonate, and white carbon, coloring agents, and the like, which are added to the abrasive grains during the production of a normal grinding wheel, can be appropriately compounded.

The abrasive compound 15 is pressed by the mold 11.
Pressure is not particularly limited, but is usually 100 to 150 kgf / cm
2 is used. Press temperature is 80 ~ 100 ℃ normal
Press temperature is used.

The disc-shaped abrasive grain compact is fired at 170 to 180 ° C. for about 24 hours. In the first 14 hours, the temperature is gradually raised from room temperature to around 170 ° C., then kept at 170 to 180 ° C. for about 10 hours, and then gradually cooled.

In firing the press-formed product of the grinding wheel according to the present invention, when laminating a large number of pieces at the same time and molding the same, the press-formed product and the thickness of 1 to 2 are set so that the grinding wheel is not distorted during firing.
mm thin iron plates are alternately stacked and laminated, and 50 to 100 press-formed products are laminated and heated and fired while applying a load to the whole, so that the grinding wheel can be fired without distortion during firing. .

Next, an example of a method of manufacturing a grinding wheel by the method of the present invention will be described in more detail. 100 parts by weight of a 60-mesh green silicon carbide powder, 18 parts by weight of a liquid phenol resin, 650 parts by weight of cryolite powder filler, and a small amount of a coloring agent are mixed to obtain an abrasive compound A. On the other hand, 100 parts by weight of green silicon carbide powder of 60 mesh, liquid phenol resin 5
Parts by weight, 15 parts by weight of powdery phenol resin, cryolite powder 5
A weight part and a small amount of a coloring agent are mixed to obtain an abrasive grain composition B. Abrasive composition A and B are appropriately mixed and used. Abrasive mixture A and B are mixed at a mixing ratio of 3: 7 to 2: 8, and are mixed at about 70 ° C. in advance.
A lower abrasive layer 18a is uniformly spread to a thickness of about 2 mm on the lower mold 2 in the mold 11 shown in FIG. Lay cloth 16. Further, an abrasive composition having the same composition as that of the lower abrasive layer 18a is further uniformly filled as the upper abrasive layer 18b to a thickness of 2 mm. Finally, the metal reinforcing ring 19 is placed on the top of the central part of the abrasive layer 18. An upper mold 4 having a rectangular wave-shaped wave pattern 14 extending radially on its lower surface is put on the abrasive layer 18 and pressurized to 80 kgf / cm ² by a 100 t hydraulic press to form the shapes shown in FIGS. Then, a disk-shaped press-formed product having a diameter of 105 mm was obtained. The pressing temperature is 90 ° C. This press-formed product 50
The sheets are alternately laminated with iron plates each having a thickness of 0.7 mm, placed in a firing furnace, heated to a predetermined temperature in 14 hours, and then maintained at that temperature for 10 hours, and then left to cool as it is.

Using this cutting wheel 5, an iron plate, a brass plate,
When the surface of the aluminum plate is cut, there is no clogging of the grinding wheel at all, it can be cut at several times the speed of the conventional cutting wheel, and the life of the grinding wheel is long,
During use, the grinding wheel has no cracks, defects, etc. and can be operated extremely safely.

Example 1 A 105 mm diameter was obtained by the above method.
On the lower mold 2 having a rectangular wave-shaped wave 14 radially on the upper surface, the compounding ratio of the abrasive grain compounds A and B of the upper and lower abrasive layers is 3: 7, and the wave-shaped rectangular wave 14 is formed radially. It is pressed with the upper die 4 (FIG. 8), which is baked, and the number of the convex portions 7 is 18,
A cutting wheel 5 having a wave height h of 0.6 mm, a thickness of the convex portion 7 of 2.4 mm, and a thickness of the concave portion 8 of 1.2 mm was produced. A workpiece made of a steel rod (SS11) having a diameter of 16 mm was cut by the cutting wheel 5 at a load of 3000 and 4300 rpm and a load of 3 kgf, and tested. Table 1 shows the test results. The cutting speed is shown as a comparative value, with the conventional cutting wheel manufactured in exactly the same manner using the upper mold 4 and the lower mold 2 having no corrugation as a comparative example and the cutting speed of the comparative example as 1.

[Table 1]

[Embodiment 2] As in Embodiment 1, FIG.
As shown in Fig. 5, a cutting wheel 5 having sawtooth waves radially provided was manufactured. The cutting height of the sawtooth wave was 0.5 mm, and the other conditions were exactly the same as those in Example 1. The same cutting test was performed on the cutting wheel 5 produced in the same manner as in Example 1. The results are shown in Table 1.

[0032]

According to the method of manufacturing a grinding wheel of the present invention, as shown schematically in FIG. 13, a fixed height indicated by a chain line is placed on a lower mold 2 having irregularities on the upper surface of a mold 11. When the abrasive layer 18 uniformly deposited to the position H is pressed by the upper mold 4 having irregularities on the lower surface and compressed as it is at a high pressure, it is compressed to the thickness of H ₂ by the corrugations 14 of the lower mold 2 and the upper mold 4. Recess 8
Has a high compression ratio from H ₁ to H _{2 and} a high density portion 20, and the convex portions 7 compressed by the concave portions of the lower die 2 and the upper die 4 are compressed only from the thickness of H ₃ to H _4. Because it is not
The compression ratio of the abrasive layer 18 is low, and that portion is
Becomes

According to the grinding wheel of the present invention, the surface of the grinding wheel has irregularities, and the abrasive density inside the recess 8 is high. The surface is repeatedly contacted in order from the high-density part to the low-density part of the grinding wheel, and then to the space part. As a result, the surface condition changes moment by moment, and the surface is continually slid on a conventional grinding wheel of the same density. The cutting speed is surprisingly higher than when moving. This is because the abrasive grains in the low-density part of the grinding wheel fall off and enter between the adjacent high-density part and the metal surface being cut. It is presumed that this is because the surface of the high portion is shaved and the surface is renewed to remove metal fine particles that are easily clogged in the gaps between the abrasive grains. Further, the concave portion on the surface of the grinding wheel has an effect of removing cut metal powder and the like, and from this point, it effectively acts to prevent clogging of the grinding wheel.

The wave shape of the surface of the grinding wheel of the present invention is such that the grinding wheel and the metal to be cut are cooled by interrupting the sliding of the grinding wheel and the metal being cut during the rotation of the grinding wheel, and the life of the grinding wheel is reduced. Can be greatly extended.

The cutting wheel 5 of the present invention can also be applied to a diamond cutting wheel using diamond abrasive grains. In that case, expensive diamond abrasive grains can be mixed with ordinary abrasive grains and placed only on the periphery of the grinding wheel.

[0036]

According to the grinding wheel of the present invention, the cutting speed is greatly improved as compared with a conventional ordinary grinding wheel, and no clogging of the grinding wheel occurs even when cutting a soft metal. The life of the grinding wheel is greatly extended, a high cutting speed can be obtained even when the rotation speed of the grinding wheel is reduced, and there is no risk of breakage of the grinding wheel during cutting. Carbide special steel can hardly be cut by a conventional cutting wheel, but can be easily cut by a cutting wheel of the present invention.

According to the method for manufacturing a grinding wheel of the present invention, it is possible to manufacture a grinding wheel having portions having different densities by an extremely simple method, and it is possible to reduce the manufacturing cost and make the product quality uniform. .

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a conventional molding die for a grinding wheel.

FIG. 2 is a perspective view of a conventional molding die of a grinding wheel.

FIG. 3 is a plan view of an example of the grinding wheel of the present invention.

FIG. 4 is a sectional view taken along line AA of an example of the grinding wheel of the present invention.

FIG. 5 is a sectional view along an arc BB of an example of the grinding wheel of the present invention.

FIG. 6 is a plan view of an example of the grinding wheel of the present invention.

FIG. 7 is a plan view of an example of the grinding wheel of the present invention.

FIG. 8 is a sectional view taken along an arc of an example of the grinding wheel of the present invention.

FIG. 9 is a sectional view along an arc of an example of the grinding wheel of the present invention.

FIG. 10 is a sectional view along an arc of an example of the grinding wheel of the present invention.

FIG. 11 is a sectional view taken along an arc of an example of the grinding wheel of the present invention.

FIG. 11 is a sectional view taken along an arc of an example of the grinding wheel of the present invention.

FIG. 13 is a cross-sectional view illustrating a method for manufacturing the grinding wheel of the present invention.

[Explanation of symbols]

 Reference Signs List 1 cylinder 2 lower mold 3 abrasive grains 4 upper mold 5 cutting wheel 7 convex part 8 concave part 9 side surface 10 wave 11 mold 12 pin 13 center hole 14 corrugation 15 abrasive compound 16 reinforcing cloth 17 press mold 18 abrasive layer 19 Reinforcement ring 20 High density part 21 Low density part

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-42482 (JP, A) JP-A-63-300872 (JP, A) JP-A-3-228579 (JP, A) JP-A-60-1985 232875 (JP, A) JP-A-59-102575 (JP, A) JP-A-6-312377 (JP, A) JP-A-1-101765 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B24D 5/14 B24D 3/00 340 B24D 5/12

Claims (6)

(57) [Claims] An abrasive grain composition comprising an abrasive grain and a binder, etc., is used together with a reinforcing cloth made of at least one glass fiber or the like.
To, and compressed into a disc shape, firing was formed by cutting the grinding wheel, the cutting irregularities in the both sides of the grinding wheel is provided, the unevenness corrugated
Wave height of 7 to 30% of the maximum thickness of the cutting wheel
The unevenness on both sides of the cutting wheel is symmetrical with each other.
It formed into so that a small abrasive grain density inside of the convex portion of the concavo-convex, the abrasive density is large Kunar so within the recess,該切
A cutting wheel in which the entire cutting wheel is integrally formed . 2. The abrasive grain density in an arc-shaped cross section along each concentric circle whose concavities and convexities are within a range used for cutting of the cutting wheel among concentric circles around the rotation axis of the cutting wheel. The cutting wheel according to claim 1, wherein the concave portions having a large diameter and the convex portions having a small abrasive grain density are alternately arranged. 3. The cutting wheel according to claim 1, wherein the concave and convex portions comprise a concave portion and a convex portion extending in a substantially radial direction from a center portion of the cutting wheel toward an outer peripheral portion thereof, and the cross section along a concentric circle concentric with the center of the cutting wheel. The cutting wheel according to claim 1, wherein the surface of the cutting wheel has a wavy shape such as a rectangular wave, a sawtooth wave, a triangular wave, a trapezoidal wave, or a substantially sinusoidal wave. 4. The cutting wheel according to claim 3, wherein the shape of the surface of the cutting wheel in a cross section along a concentric circle concentric with the center of the cutting wheel is rectangular. 5. An abrasive made of abrasive powder in which a binder is mixed between an upper mold and a lower mold in a cylinder set so that a disc-shaped lower mold is fitted to the bottom and the axis is vertically set. In a method of manufacturing a grinding wheel in which the compound is sandwiched and pressed at a high pressure to form a disc, and then the disc-shaped molded product is heated and fired, a constant amount is formed on the upper surface of the lower mold having irregularities on the upper surface in the cylinder. An abrasive grain composition is deposited to a thickness to form an abrasive layer, and an upper mold having irregularities on a lower surface is placed on the abrasive layer and press-molded, and a circle having mutually symmetric irregularities on both surfaces is formed. A method for manufacturing a grinding wheel, wherein a distribution of abrasive grain density is formed from a portion having a high abrasive grain density to a portion having a low abrasive grain density in a cutting wheel by molding into a plate shape. 6. The method for manufacturing a grinding wheel according to claim 5 , wherein one or more glass fiber reinforcing cloths are interposed on both sides or in the middle of said abrasive layer to deposit said abrasive layer and press-mold.