JP2003089064A - Rotary truer and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary truer capable of reducing the wear of a combined material and having excellent holding force of ultraabrasive grains and a manufacturing method therefor. SOLUTION: This rotary truer in which an abrasive grain layer part 3 containing ultraabrasive grains and metallic powders is formed on an outer peripheral face of a base metal unit 1 by sintering is characterized to have a peak of particle diameter of large diameter ultraabrasive grains and a peak of particle diameter of minute ultraabrasive grains in its particle size distribution. This rotary truer manufacturing method is provided for forming the abrasive grain layer part by filling a granulated material 6, granulated the large diameter ultraabrasive grains coated with metallic powders containing minute ultraabrasive grains, into molds 4, 7, and pressing, sintering it. In this manufacturing method, metallic powders with higher hardness than the metallic powders coated the large diameter ultraabrasive grains are filled into at least one side of the granulated material like layers to form a reinforced layer 9 with higher hardness than a combined material in the abrasive grain layer part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary truer and its manufacturing method. More specifically, the present invention relates to a rotary truer having a small amount of wear of a binder and an excellent holding force for superabrasive grains, and a method for manufacturing the same.

[0002]

2. Description of the Related Art A super-abrasive grain wheel using super-abrasive grains such as CBN abrasive grains and diamond abrasive grains as a blade material, a silicon carbide-based GC abrasive grain, and an aluminum oxide-based WA abrasive grain as a blade material If the grinding wheel used as above is continuously used for grinding and cutting, the wheel is worn, the sharpness is gradually reduced, and the surface roughness and the shape are defective. If the wheel is eccentric or rotated at high speed without being a perfect circle, it will have various adverse effects on the workpiece and machine.Therefore, the convex portion on the working surface of the wheel will be scraped off, and the grinding working surface will become the center of the shaft. Truing to concentrically shape is performed. Conventionally, in such a truing operation, a rotary truer composed of a ring-shaped base metal and an abrasive grain layer portion provided on an outer peripheral portion of the base metal is traversed in the width direction. Normally, the width of the abrasive grain layer of the rotary truer is very thin, around 1 mm,
Superabrasive grains are dispersed in this abrasive grain layer. A rotary truer with a narrow width of the abrasive grain layer is likely to damage the abrasive grain layer during truing or to cause the superabrasive grains to drop off from the side surface of the abrasive grain layer. Various attempts have been made to prevent this. For example, Japanese Examined Patent Publication No. 7-16884 discloses a ring-shaped base, a thin whetstone portion, and a thin whetstone portion as a thin whetstone that does not break during traverse grinding or when manufacturing the thin whetstone portion. There has been proposed a thin width abrasive grain grinding wheel including a reinforcing portion integrally formed on at least one surface and containing no hard abrasive grains. In addition, JP 2000-1
No. 08038 discloses a granulated product in which superabrasive grains are coated with metal powder and granulated as a wheel dresser that eliminates uneven distribution of superabrasive grains on the outer peripheral side of the grindstone portion and prevents the superabrasive grains from falling off from the side face of the grindstone portion. There has been proposed a wheel dresser in which a layer containing no superabrasive grains is formed on both side surfaces and the outermost peripheral portion of a grindstone portion formed by pressure molding and firing. According to these techniques, it is possible to increase the strength of the thin abrasive grain layer and prevent the superabrasive grains from falling off from the side surface of the abrasive grain layer, but there is no superabrasive grain in the abrasive grain layer. Due to the existence of the region, the abrasion of the abrasive grain layer in the radial direction is accelerated, the holding force of the superabrasive grains is weak, and the rotary truer is frequently replaced. Also,
Even when the reinforcing portion is provided, there is a problem that the abrasive grain layer portion and the reinforcing portion cause uneven wear due to the drop of the superabrasive grains in the abrasive grain layer portion.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a rotary truer having a small amount of wear of a bonding material and an excellent holding force for superabrasive grains, and a method for producing the same.

[0004]

As a result of intensive studies to solve the above-mentioned problems, the present inventor has found that when the binder of the abrasive grain layer contains fine superabrasive grains, the wear of the binder is increased. To increase the holding power of the superabrasive grain and extend the life of the rotary truer.In addition, when the reinforcing layer is provided on the side surface of the abrasive grain layer, the metal of the reinforcing layer should be harder than the bonding material. It was found that a good reinforcing effect can be obtained, and the present invention has been completed based on this finding. That is, according to the present invention, (1) in a rotary truer in which an abrasive grain layer portion containing superabrasive grains and metal powder is formed on the outer peripheral surface of a base metal by sintering, the grain size distribution of the superabrasive grains has a large diameter. A rotary truer having a peak of the particle size of superabrasive grains and a peak of the particle size of fine superabrasive grains, (2) The position of the peak of the grain size of large-diameter superabrasive grains is 150 to 1,000 μm. The rotary truer according to the first aspect, wherein the position of the peak of the grain size of the fine superabrasive grains is 5 to 60 μm, and (3) the superabrasive grains are large-diameter superabrasive grains 80 to 9
The rotary truer according to the first aspect, which comprises 9.9% by volume and 0.1 to 20% by volume of fine superabrasive grains, and (4) hardness on at least one side of the abrasive layer portion, which is higher than that of the binder of the abrasive layer portion. A rotary truer according to claim 1 having a high reinforcing layer, and (5)
Manufacturing a rotary truer in which a large-diameter superabrasive grain is coated with a metal powder containing fine superabrasive grains and the granulated material is filled into a mold, pressure-molded, and sintered to form an abrasive grain layer portion. A method for filling at least one side of the granulated material with a layer of metal powder having a hardness higher than that of the metal powder coated with large-diameter superabrasive grains, and reinforcing the abrasive grain layer portion to have a hardness higher than that of the binder. A method for manufacturing a rotary truer, which comprises forming a layer.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The rotary truer of the present invention is a rotary truer in which an abrasive grain layer portion containing superabrasive grains and metal powder is formed on a peripheral surface of a base metal by sintering. The distribution is a rotary truer having a peak of the grain size of the large-diameter superabrasive grains and a peak of the grain size of the fine superabrasive grains. Figure 1 (a)
FIG. 1B is a plan view of an example of a rotary truer, and FIG.
[FIG. 4] is a cross-sectional view taken along a plane passing through the central axis. In the rotary truer of this figure, an abrasive grain layer portion 3 containing superabrasive grains and metal powder is formed on an outer peripheral surface 2 of a base metal 1. In the rotary truer of the present invention, the particle size distribution of the superabrasive grains contained in the abrasive grain layer portion has two peaks, that is, the peak of the large-diameter superabrasive grains and the peak of the fine superabrasive grains. The large-diameter super-abrasive grains contained in the abrasive grain layer part, similar to the super-abrasive grains contained in the abrasive grain layer part of a normal rotary truer, scrape the convex part on the working surface of the grinding tool to be trued. It acts to drop. The fine superabrasive grains contained in the abrasive grain layer portion strengthen the binder made of sintered metal powder, so that abrasion and deformation of the binder portion are prevented, and the large-diameter superabrasive grains are firmly bonded by the binder. It is retained and the rotary truer has a long life. When the width of the abrasive grain layer portion is twice or more the average grain size of the large-diameter superabrasive grains, the region where the superabrasive grains do not exist increases, but by uniformly dispersing the fine superabrasive grains, The binding material can be strengthened to prevent early wear and prevent the large-diameter superabrasive grains from falling off.

In the rotary truer of the present invention, the position of the peak of the grain size of the large-diameter superabrasive grains is 150 to 1,000 μm.
It is preferably m, and more preferably 250 to 600 μm. In order to set the peak position of the particle diameter of the large-diameter superabrasive particles to 150 to 1,000 μm, JIS B 4
It is possible to use superabrasive grains having a grain size of 80/100 to 18/20 specified in 130. If the peak position of the particle diameter of the large-diameter superabrasive particles is less than 150 μm, the sharpness of the rotary truer may be insufficient. If the position of the peak of the grain size of the large-diameter superabrasive grains exceeds 1,000 μm, the width of the grain layer portion of the rotary truer may become too thick. In the rotary truer of the present invention, the position of the peak of the grain size of the fine superabrasive grains is preferably 5 to 60 μm, and more preferably 10 to 30 μm. In order to set the peak position of the grain size of the fine superabrasive grains to 5 to 60 μm, superabrasive grains having a grain size of 3000 to 325/400 can be used. The position of the peak of the fine superabrasive grain size is 5μ
If it is less than m or more than 60 μm, the effect of strengthening the binder may be insufficient. In the rotary truer of the present invention, the superabrasive grains are large-diameter superabrasive grains 80-9.
It is preferably composed of 9.9% by volume and fine superabrasive grains of 0.1 to 20% by volume, and more preferably large diameter superabrasive grains of 93 to 98% by volume and fine superabrasive grains of 2 to 7% by volume. In the particle size distribution curve of the superabrasive grain, a superabrasive grain having a grain size larger than the minimum point is defined as a large-diameter superabrasive grain, and a superabrasive grain having a grain size smaller than the minimal point is defined as a boundary. Use fine super abrasive grains. If the proportion of fine superabrasive grains in the superabrasive grains is less than 0.1% by volume, the effect of strengthening the binder may be insufficient. When the proportion of the fine superabrasive grains in the superabrasive grains is 20% by volume or less, a sufficient effect can be obtained, and normally, the fine superabrasive grains exceeding 20% by volume are unnecessary.

Examples of superabrasive grains used in the rotary truer of the present invention include CBN abrasive grains, natural diamond abrasive grains, and synthetic diamond abrasive grains.
Examples of the metal powder used to form the binder in the rotary truer of the present invention include, for example, copper, tin, cobalt, iron, nickel, single metal powder such as tungsten, and steel,
Examples thereof include metal powder of alloy such as bronze. These metal powders can be used individually by 1 type, or can also be used in combination of 2 or more type. The rotary truer of the present invention preferably has a reinforcing layer having a hardness higher than that of the binder of the abrasive grain layer portion on at least one side of the abrasive grain layer portion. By making the hardness of the reinforcing layer provided on at least one side of the abrasive grain layer portion higher than the hardness of the binder of the abrasive grain layer portion, the abrasive grain layer portion and the reinforcing layer are worn almost uniformly during truing, and stable truing is achieved. The performance can be maintained for a long time. The difference in hardness between the binder and the reinforcing layer is preferably 10 to 500, and more preferably 30 to 200 in terms of Brinell hardness. When the difference in Brinell hardness between the binder and the reinforcing layer is less than 10, the reinforcing layer is worn more quickly than the abrasive grain layer portion, and the reinforcing effect of the reinforcing layer may be insufficient. When the difference in Brinell hardness between the binder and the reinforcing layer exceeds 500, the abrasive grain layer portion is worn more quickly than the reinforcing layer, and it may be difficult to maintain stable truing performance.

The method for manufacturing a rotary truer of the present invention is as follows.
Manufacturing a rotary truer in which a large-diameter superabrasive grain is coated with a metal powder containing fine superabrasive grains and the granulated material is filled into a mold, pressure-molded, and sintered to form an abrasive grain layer portion. A method for filling at least one side of the granulated material with a layer of metal powder having a hardness higher than that of the metal powder coated with large-diameter superabrasive grains, and reinforcing the abrasive grain layer portion to have a hardness higher than that of the binder. Form the layers. There is no particular limitation on the method of granulating the large-diameter superabrasive particles with a metal powder containing fine superabrasive particles, for example, by suspending the large-diameter superabrasive particles in a granulating device equipped with a circulating fluid tank, Powder, fine superabrasives, organic binder,
Coated granulation can be carried out by adding an organic solvent or the like. FIG. 2 is an explanatory view of one embodiment of the method for manufacturing a rotary truer of the present invention. As shown in FIG. 2A, the base metal 1 is fitted into the recess of the lower mold 4, and the outer mold 5 is attached to the outer periphery of the lower mold. Next, a predetermined amount of the granulated material 6 obtained by coating and granulating the large-diameter superabrasive grains with the metal powder containing the fine superabrasive grains is put into the space between the base metal and the outer die. As shown in FIG. 2 (b), the upper die 7 is mounted and pressed to compress the granulated material, causing plastic deformation of the metal that coats the large-diameter superabrasive particles, and the abrasive layer portion. Is pressure-molded. Once the upper mold is removed, a layer of metal powder 8 having a hardness higher than that of the metal powder coated with the large-diameter superabrasive particles is layered on the abrasive grain layer portion, the upper mold is mounted again, and heating is performed under pressure. Thereby, the abrasive grain layer portion is sintered and the reinforcing layer is formed. Then, the outer mold, the upper mold, and the lower mold are removed to complete the rotary truer having the abrasive grain layer portion 3 reinforced by the reinforcing layer 9 on one side on the outer peripheral surface 2 of the base metal 1.

[0009]

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Example 1 Large diameter synthetic diamond abrasive grain 1.0 having an average grain size of 350 μm
0.05 parts by weight of fine synthetic diamond abrasive grains having an average particle size of 30 μm and 27.1 parts by weight of bronze (Brinell hardness 65) powder are charged into a granulator together with an acrylic resin and isopropyl alcohol, and a large diameter abrasive grain is prepared. Is coated with bronze powder containing fine abrasive grains and has an average particle size of 800 μm
To obtain a granulated product. A 100D × 8H × 20T base metal made of S45C was prepared, and the base metal, the lower mold, and the outer mold were assembled in the state shown in FIG. Then, the above granules are filled between a base metal and an outer mold, an upper mold is attached, pressure molding is performed at a pressure of 300 MPa, and then heating is performed at 600 ° C. for 60 minutes under a pressure of 100 MPa, A rotary abrasive was completed by forming a diamond abrasive grain layer portion having a width of 5.5 mm and a thickness of 0.6 mm on the outer peripheral portion of gold. A vitrified CBN wheel was trued using this rotary truer. Truing conditions are wheel peripheral speed of 80 m / sec and dress peripheral speed ratio of 0.
5, down cut, dress depth 0.005mm / pass,
The dress lead was 0.15 mm / rev. Dress efficiency is 1
It was 35. Example 2 The same operation as in Example 1 was performed until the granules were filled between the base metal and the outer mold and the upper mold was mounted, then pressure molding was performed at a pressure of 320 MPa, and the upper mold was removed. Then, cobalt (Brinell hardness 124) powder was supplied in layers on the pressure-molded abrasive grain layer portion, and the upper die was mounted again. Then 100MP
Heated at 750 ° C for 60 minutes under pressure of a, and a cobalt reinforcing layer with a width of 5.5 mm and a thickness of 0.2 mm and a width of 5.5 m on the outer periphery of the base metal.
A diamond truer layer having a thickness of m and a thickness of 0.6 mm was formed to complete the rotary truer. Using this rotary truer, a vitrified CBN wheel was trued in the same manner as in Example 1. Dress efficiency is 160
Met. Comparative Example 1 Large diameter synthetic diamond abrasive grain with an average grain size of 350 μm 1.0
Parts by weight and bronze (Brinell hardness 65) powder 27.2
A rotary truer was produced in the same manner as in Example 1 except that a granulated product prepared by using parts by weight and containing no fine synthetic diamond abrasive grains was used. Using this rotary truer, in the same manner as in Example 1, vitrified C
The BN wheel was trued. Dress efficiency is
It was 100. The results of Examples 1 and 2 and Comparative Example 1 are
It is shown in Table 1.

[0010]

[Table 1]

As can be seen from Table 1, compared with the truing of Comparative Example 1 using the conventional rotary truer, the rotary truer containing fine diamond abrasive grains in the binder of the abrasive grain layer is used. The dressing efficiency is excellent in Example 1 and the dressing efficiency is further excellent in Example 2 in which the rotary truer in which the diamond abrasive grain layer has the cobalt reinforcing layer is used.

[0012]

EFFECT OF THE INVENTION The rotary truer of the present invention has less wear of the bonding material, excellent holding power for superabrasive grains, and long life. According to the method of the present invention, such a rotary truer can be easily manufactured.

[Brief description of drawings]

FIG. 1 is a plan view and a cross-sectional view of an example of a rotary truer.

FIG. 2 is an explanatory view of one embodiment of a method for manufacturing a rotary truer of the present invention.

[Explanation of symbols]

1 unit 2 outer peripheral surface 3 Abrasive layer 4 Lower mold 5 External type 6 granules 7 Upper mold 8 High hardness metal powder 9 Reinforcement layer

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) B24D 3/06 B24D 3/06 A 5/04 5/04

Claims (5)

[Claims] 1. In a rotary truer in which an abrasive grain layer portion containing superabrasive grains and metal powder is formed on the outer peripheral surface of a base metal by sintering, the grain size distribution of the superabrasive grains is large. A rotary truer having a particle size peak and a particle size peak of fine superabrasive grains. 2. The peak position of the particle diameter of the large-diameter superabrasive grains is 150.
The rotary truer according to claim 1, wherein the particle diameter of the fine superabrasive grains is at a peak position of 5 to 60 µm. 3. The superabrasive grains are large-diameter superabrasive grains of 80 to 99.9% by volume and fine superabrasive grains of 0.1 to 20% by volume.
The rotary truer described. 4. The rotary truer according to claim 1, wherein a reinforcing layer having a hardness higher than that of the binder of the abrasive grain layer portion is provided on at least one side of the abrasive grain layer portion. 5. A mold is filled with a granulated product obtained by coating and granulating large-diameter super-abrasive grains with metal powder containing fine super-abrasive grains, pressure-molded, and sintered to form an abrasive grain layer portion. A method for manufacturing a rotary truer, wherein at least one side of the granulated material is filled with a layer of metal powder having a hardness higher than that of the metal powder coated with large-diameter superabrasive particles,
A method for manufacturing a rotary truer, which comprises forming a reinforcing layer having a hardness higher than that of the binder in the abrasive grain layer portion.