JP2004255469A - Structure of grinding part in grinding tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structure of a grinding part in a grinding tool, by which fixing strength of brazed diamond grains to a surface of a grinding part is kept intact, and releasing of the diamond grains is reduced. <P>SOLUTION: In the structure of the grinding part in the grinding tool having diamond grains 2 brazed to the surface 1a of the grinding part, powder 8 having a melting point higher than that of the brazing material 7 and excellent wettability with the brazing material 7 is mixed into a brazing material 7. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a grinding unit structure of a grinding diamond disk used for grinding various objects to be ground using a grinding tool, specifically, a disk grinder or a file, a jigsaw, a hand saw, or the like.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, as a grinding tool, a diamond disk for grinding, in which a diamond piece is fixed to a disk surface made of a steel plate while leaving a central portion thereof, has been used.
[0003]
This type of diamond disk is used for grinding objects to be polished such as concrete, stone, and tiles by attaching it to the rotating shaft of a disk grinder through a mounting hole provided in the center of the disk and rotating it at high speed. Various diamond disks having different sizes and shapes of disks, and different particle sizes and densities of diamond flakes adhered to the disk surface are commercially available in accordance with the purpose of use.
[0004]
The applicant has previously proposed a diamond disk as shown in FIG. This diamond disk is adjacent to a diamond disk in which the center portion 4 of the disk 1 having the mounting hole 3 is left, and the diamond particle 2 is fixed to the desk surface 1a from the middle portion 5 of the disk surface 1a to the peripheral edge 6 thereof. The fixed positions of the plurality of the diamond pieces 2 are patterned to form the diamond particle group units A, and the diamond particle group units A are arranged on the disk surface 1a to position the respective diamond particles 2. Is fixed to the disk surface 1a. (See Patent Document 1).
[0005]
In the diamond disk having the above-described configuration, on the disk surface, a plurality of diamond particles belonging to the same diamond particle group unit are close to each other and have a surface spread, so that they are used for grinding concrete or stone materials. Therefore, grinding with these diamond particles is treated collectively, and can be regarded as grinding that broadens the apparent rotation trajectory. By doing so, the positioning of each diamond particle on the disk surface can be easily performed, and in terms of performance, the grinding performance is comparable to the conventional one that positions individual diamond particles on the disk surface. Demonstrate.
[0006]
[Patent Document 1]
Japanese Patent Application No. 2002-367807.
[0007]
[Problems to be solved by the invention]
However, as shown in FIG. 4, the bonding of the diamond particles to the disk surface of the diamond disk having the above-described structure is performed by attaching the general-purpose brazing material 7 to the disk surface 1a with the entire diamond particles 2 disposed on the disk surface 1a. When the temperature of the brazing material 7 has reached the melting temperature, the brazing material 7 melts like water around the diamond particles 2 to reduce the adhesion of the diamond particles 2. There is a case where it weakens and develops into the detachment of the granule pieces 2 of the diamond.
[0008]
Therefore, the present invention provides a grinding part structure of a grinding tool in which the brazing adhesion strength of the diamond particles to the grinding surface, that is, the disk surface of the diamond disk, etc., is kept constant, and the falling of the diamond particles is reduced. It is intended for.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, a grinding part structure of a grinding tool according to the present invention has a melting point higher than that of a brazing filler metal in a grinding part structure of a grinding tool in which a diamond piece is fixed to a grinding part surface by brazing. It is characterized in that the diamond flakes are brazed with a brazing material mixed with a powder having good wettability.
[0010]
Here, the grinding part surface of the grinding tool is a diamond disk surface made of a steel plate or an opening edge of a core body which is a cutting edge of a core drill, and the arrangement of the diamond particles and the brazing and fixing method thereof are described. Is the same as the well-known one.
[0011]
According to the grinding part structure of the grinding tool configured as described above, a diamond particle is fixed to the grinding part surface of the grinding tool by brazing, and powder having a melting point higher than that of the brazing material is contained in the brazing material. Since the powder remains in its original form, when the temperature of the brazing material reaches the melting temperature, the melted brazing material starts flowing around the particle of the diamond particle, and the powder remaining in the original shape around the particle of the diamond particle blocks it and blocks it. I do. In this manner, the brazing adhesion strength of the diamond particles is maintained, and the diamond particles are prevented from developing into falling off.
[0012]
Further, in the above structure, the powder mixed with the brazing material is not particularly limited in terms of material as long as it has a higher melting point than the brazing material and has good wettability with the brazing material. However, if it is composed of a single element such as cobalt, nickel, iron or a mixture of these plural elements, these materials are easily available and have excellent practicality.
[0013]
When the above-mentioned cobalt, nickel, iron, or the like is used as a powder, the mixing ratio of the powder to the brazing material is preferably set to 10 to 50%.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings.
[0015]
FIG. 1 is a longitudinal sectional view of a diamond disk showing an embodiment of the present invention, and FIG. 2 is a partially enlarged view showing a structure of fixing a diamond particle to a disk surface.
[0016]
The drawing in FIG. 1 corresponds to the longitudinal sectional view of the diamond disk shown in FIG. Therefore, the same parts as those in FIG.
[0017]
In FIG. 1, a grain piece 2 of a diamond is fixed to a disk surface 1 a on one side of a disk 1 made of a steel plate with a limited area.
[0018]
In the disk 1 of the embodiment, the central part 4 having the mounting hole 3 is left as a flat plate part from the disk middle part, and is depressed to one disk surface 1b side (downward in FIG. 1) at a predetermined depth. The outer peripheral portion 5 of the portion is rounded on the other disk surface 1a side (upper side in FIG. 1) to form a bulging shape. This is a mode in which a gentle curved surface is formed, and the disk outer peripheral portion 6 is warped toward the concave portion 4 (downward in FIG. 1). It is hung on the part 6 and fixed by brazing.
[0019]
In the present invention, as shown in FIG. 2, a powder 8 having a melting point higher than that of the brazing material and having good wettability with the brazing material 7 is mixed in the brazing material 7 used for fixing the diamond-shaped diamond particles 2.
[0020]
In this case, the powder 8 mixed into the brazing material 7 is a powder 8 made of cobalt, nickel, iron, or the like, which is easily available and has excellent practicality. Incidentally, the melting temperature of the powder brazing material used for vacuum brazing is about 1000 degrees, the melting point of cobalt is 1495 degrees, the melting point of nickel is 1455 degrees, and the melting point of iron is 1539 degrees. The practical mixing ratio of the powder 8 to the brazing material is about 10 to 50%.
[0021]
In the present invention, the powder 8 having a melting point higher than that of the brazing material 7 remains in the solidified brazing material 7 in a state where the diamond particles 2 are brazed and fixed to the disk surface 1a. When the temperature reaches the melting temperature, the melted brazing material starts flowing around the granule 2 and the powder 8 remaining around the granule 2 blocks the brazing material 7 from melting. In this manner, the brazing adhesion strength of the diamond pieces 2 is maintained, and the diamond pieces are prevented from developing into falling off.
[0022]
【The invention's effect】
The present invention is implemented in the form described above, and according to the present invention, a brazing material for brazing and fixing a diamond particle to a grinding portion surface of a grinding tool is mixed with a powder made of high melting point cobalt or the like. Therefore, even if the brazing filler metal is melted, the powder blocks the diamond particles around the diamond particles to maintain the bonding strength of the diamond particles, and the diamond particles 2 do not develop into falling off. An easy-to-use, high-quality grinding tool can be provided according to the purpose.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a diamond disk showing an embodiment of the present invention.
FIG. 2 is a partially enlarged view showing a structure in which a diamond particle piece is fixed to a disk surface of a diamond disk in FIG.
FIG. 3 is a front view of a conventional diamond disk.
FIG. 4 is a partially enlarged view showing a structure of attaching a diamond particle to a disk surface of a conventional diamond disk.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 disk 1a disk surface 1b disk surface 2 danmond grain piece 3 mounting hole 4 central part 5 dent outer periphery 6 disc outer periphery 7 brazing material 8 powder A danmond grain piece collective unit

Claims (3)

In the grinding part structure of the grinding tool, where the diamond particles are brazed to the surface of the grinding part, the melting point is higher than that of the brazing material, and the diamond particles are brazed with a powder mixed with powder that has good wettability with the brazing material. The grinding part structure of the grinding tool, characterized in that: The grinding part structure of a grinding tool according to claim 1, wherein the powder is made of a single element such as cobalt, nickel, iron or a mixture of a plurality of these single elements. The grinding part structure of a grinding tool according to claim 1 or 2, wherein a mixing ratio of the powder to the brazing material is set to 10 to 50%.

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