JP2000237963A - Grinding wheel having improved abrasive grain holding force - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably maintain the excellent cutting performance for a long time while evening the distribution of the abrasive grains so as to improve the holding force by arranging the abrasive grains in a net-like openings having openings smaller than the grain diameter of the abrasive grains so as to be projected from each opening, and fixing the net-body and the abrasive grains to a base metal with the blazing material. SOLUTION: An abrasive grain layer 13 provided in the inner and the outer surfaces of a tip of a swelling part 12b of a base metal is formed by arranging abrasive grains 16 in openings of a metal net 14 of titanium having openings smaller than the grain diameter of the abrasive grains 16 so as to be projected from the metal net 14. The metal net 14 and the abrasive grains 16 are fixed to the inner and the outer surfaces and a tip surface of the swelling part 12b by the blazing material such as Ag-Cu-In-Tt base. Projected quantity of the abrasive grains 16 from the metal net 14 is desirably set at 1/5-1/2 in relation to the grain diameter of the abrasive grains 16. Furthermore, double layers or more of the net bodies and the abrasive grains can be formed by similarly arranging the metal net and the abrasive grains on the abrasive grains 16 arranged in the openings of the metal net 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to diamond, CB
The present invention relates to a grinding wheel that is applied to a grinding wheel using super-abrasive grains such as N, and in particular, has improved holding power of the abrasive grains.

[0002]

2. Description of the Related Art Conventionally, a grinding wheel in which superabrasives such as diamond abrasives and CBN abrasives are fixed to one layer by an electrodeposition method or a brazing method has been used as a grinding wheel for grinding and polishing. Such a grinding wheel is required to have excellent sharpness and to maintain the sharpness stably for a long period of time. However, the sharpness and the service life of diamond abrasive grains and CBN abrasive grains decrease with the progress of the grinding operation.

[0003] The main reasons for this are that, in the case of a grinding wheel by the electrodeposition method, the state of fixed abrasive grains on the base metal is unstable and the abrasive grains are likely to fall off. Clogging may occur due to chips during the grinding operation. In addition, in the case of the grinding wheel using the brazing method, the abrasive grains may fall off due to insufficient strength of the brazing material.

As a countermeasure against this, Japanese Patent Laid-Open Publication No.
In the publication, abrasive grains are put into each mesh of a mesh member made of a non-conductive material having a mesh smaller than the grain size of the abrasive grains, and the mesh member is placed on the base so that the abrasive grains are sandwiched between the mesh and the base metal. A method of manufacturing an electrodeposited whetstone in which abrasive grains are temporarily attached by temporary plating while being pressed against gold, and then a net-like member is removed and a base metal is subjected to main plating is disclosed.
In the publication, an adhesive is applied to one side of a non-conductive mesh sheet having a mesh size larger than the abrasive grains, the abrasive grains are adhered to the coated surface, and the adhesive applied surface side is pressed against a base metal. There is disclosed a method of manufacturing an electrodeposited whetstone in which abrasive grains are temporarily fixed between a mesh sheet and a base metal, plating is performed in this state, and then the mesh sheet is removed.

Japanese Patent Application Laid-Open No. HEI 10-118937 discloses that one or a plurality of abrasive grains are formed on an outer peripheral surface of a rotating substrate at intervals of at least the grain diameter of the abrasive grains.
A cutting wheel fixed by a brazing material containing hard particles is disclosed.

[0006]

SUMMARY OF THE INVENTION The above Japanese Patent Application Laid-Open No. 1-20
According to the manufacturing method described in JP-A-5979 or JP-A-7-205034, an electrodeposited whetstone having abrasive grains uniformly distributed at predetermined intervals can be obtained. However, the grindstone manufactured by such a method has an advantage that the abrasive grains can be uniformly dispersed by using a mesh sheet or a mesh, while the abrasive grains are fixed by plating. However, there is a disadvantage that the holding power of the abrasive grains is insufficient.

The cutting wheel disclosed in the above-mentioned Japanese Patent Application Laid-Open No. Hei 10-118937 has abrasion resistance of the brazing material which is somewhat improved by adding the hard particles to the brazing material. Since the adhesive strength is reduced, there is no effect of increasing the holding power of the abrasive grains, and the problem of the abrasive grains falling off still remains. Further, since the distribution of the abrasive grains is non-uniform, the load on the individual abrasive grains and the supply of the coolant to the cutting point become non-uniform, so that there is a problem that the stability of sharpness cannot be obtained.

An object of the present invention is to provide a grinding wheel having a uniform distribution of abrasive grains, excellent abrasive grain holding power, and capable of stably maintaining good sharpness over a long period of time. is there.

[0009]

SUMMARY OF THE INVENTION The present invention is directed to a grinding wheel using superabrasives such as diamond and CBN, in which all openings or spaces of meshes having openings smaller than the grain size of the abrasives are provided. Abrasive grains are arranged in the openings, the abrasive grains are projected from the surface of the mesh body, and the mesh body and the abrasive grains are fixed to the base metal with a brazing material.

In the grinding wheel of the present invention, the distribution of the abrasive grains can be made uniform at an arbitrary interval by arranging the abrasive grains in all the openings of the mesh body or in the openings at intervals. In addition, by holding the abrasive grains to the base metal with the mesh body and brazing material in a state where the abrasive grains are projected from the surface of the mesh body having openings smaller than the grain diameter of the abrasive grains, the holding power of the abrasive grains is excellent. A grinding wheel is obtained.

In the present invention, the net-like body functions as a reinforcing material for uniformly distributing the abrasive grains and for fixing and holding the abrasive grains to the base metal. Therefore, it is desirable to use a material having excellent strength and abrasion resistance as the mesh. Titanium, titanium alloys, stainless steel, ceramics, etc. can be adopted as the material. Titanium and titanium alloys are suitable for enhancing the holding power of abrasive grains, and carbon steel is preferred in terms of workability and cost. Or stainless steel is suitable. In particular, when a mesh made of titanium or a titanium alloy is used, the carbon in the abrasive grains reacts with the titanium in the mesh to generate titanium carbide, and a strong abrasive grain holding force is obtained.

Here, it is desirable that the protrusion amount of the abrasive grains from the surface of the mesh is in the range of １ ／ to １ ／ of the particle diameter of the abrasive grains. If the protrusion amount is smaller than 1/5 of the abrasive grain size, the portion contributing to the cutting is small, so the cutting amount is small, the sharpness is poor, and the chips are difficult to be discharged, and the clogging is easy to be performed. The reticulated body is easily worn. Further, the impact at the time of grinding is large, and the abrasive grains are easily broken. on the other hand,
If it is larger than ２, the abrasive holding force of the mesh body is reduced, and the abrasive is likely to fall off. When the protruding amount is within the above range, the abrasive grains sufficiently bite into the material to be ground and are ground, and chips are efficiently discharged, without clogging or seizure, and stable sharpness is obtained. Can be

Further, as the grinding wheel of the present invention, the abrasive grains are arranged at the openings of the mesh body as described above, and the mesh body and the abrasive grains are further similarly arranged to form a layer of the mesh body and the abrasive grains. Can be formed in two or more layers. In this case, by arranging the outer layer abrasive grains and the inner layer abrasive grains so as not to overlap, a uniform abrasive grain distribution can be obtained as a whole.
Furthermore, by forming a plurality of layers, even if the abrasive grains in the outer layer are crushed, the abrasive grains in the inner layer protrude, so that the grinding can be performed continuously.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on an embodiment in which the present invention is applied to a core bit. 1 is an overall perspective view of a core bit according to an embodiment of the present invention, FIG. 2 is a partial longitudinal sectional view of the core bit shown in FIG. 1, and FIG. 3 is a partial plan view showing an arrangement of abrasive grains in an abrasive layer.

In the drawing, reference numeral 10 denotes a core bit, 12 denotes a cylindrical base metal forming a main body of the core bit, and the base metal 12 is
Base 12 having an outer diameter of 30 mm and a thickness of 2 mm located on the machine side
a, and a bulging portion 12b located at the tip of the base portion 12a and having a larger thickness than the base portion 12a. 11 attached to the bottom surface of the base 12a is a core bit 1
0 is a boss for attaching to the rotating shaft of the machine, and the inside is hollow so that grinding fluid can be supplied.

As shown in FIG. 2, an abrasive layer 13 is formed on the distal end surface of the bulging portion 12b of the base metal 12 and on the inner and outer surfaces within a range of about 5 mm from the distal end surface. The abrasive layer 13 is shown in FIG.
As shown in FIG. 2, the abrasive grains 16 are arranged in the openings 15 of the titanium mesh 14 having openings smaller than the grain size of the abrasive grains 16, and the abrasive grains 16 protrude from the surface of the wire mesh 14. Ag-Cu-In-Ti-based brazing filler metal 1
7, and is fixed to the inner and outer surfaces and the distal end surface of the bulging portion 12b of the base metal 12.

In this embodiment, the opening is 450 μm.
In the opening 15 of the wire mesh 14 having a wire diameter of 100 μm, abrasive grains 16 having a particle diameter of 460 to 550 μm are arranged in a zigzag manner at intervals of one mesh, and the abrasive grains 16 are mounted on the wire mesh 14 and the brazing material 17. It is fixed to gold 12. The amount of protrusion of the abrasive grains 16 from the surface of the wire mesh 14 is about 130 to 175 μm, which is about の of the grain size of the abrasive grains.

By forming the abrasive grain layer 13 in this manner, the abrasive grains 16 have a uniform distribution over the entire surface of the abrasive grain layer 13 and have a smaller size than the surface of the metal mesh 14 having openings smaller than the grain size of the abrasive grains 16. By brazing the abrasive grains 16 to the base metal 12 with the wire mesh 14 and the brazing material in a state where the abrasive grains 16 are protruded, an abrasive grain layer 13 excellent in holding force of the abrasive grains 16 is obtained.

FIG. 4 is a diagram showing a cross-sectional structure of an abrasive layer in another embodiment in which a mesh and abrasive layers are formed in two layers. In the present embodiment, the bulging portion 12b shown in FIG.
An abrasive layer 23 having the same configuration as that of the abrasive layer 13 is formed on the abrasive layer 13 on the front end surface of the substrate. The second abrasive layer 23,
The abrasive grains 26 are arranged at the positions of the metal mesh openings where the abrasive grains 16 are not arranged in the first abrasive grain layer 13, and the first abrasive grains 1
The abrasive grains 26 of the second layer together with the wire mesh 6 and the wire mesh 14 are fixed to the base metal by the wire mesh 24 and brazing material.

With such a two-layer structure,
Even if the abrasive grains in the layer are crushed, they can be continuously ground by the abrasive grains in the first layer. Further, since the second-layer abrasive grains are arranged in the first-layer wire mesh opening together with the second-layer wire mesh opening, an effect of being more firmly fixed can be obtained.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A core bit (inventive product) according to the present invention shown in FIGS. 1 and 2 and a core bit (comparative product) in which an abrasive layer was formed in the basic shape shown in FIG. 1 by the method described in JP-A-10-118937. ) Was used to perform a drilling test on concrete.

[Test conditions] Machine used: motor 100V, 10.5A, rotation speed 10
00 rpm Drilling method: Wet type (cooling water amount 1.5 L / min) Drilling depth 200 mm, manual feed Work material: Reinforced concrete, thickness 200 mm

[Test Results] The invention product was excellent in the holding power of the abrasive grains, did not drop off the abrasive grains during the drilling operation, and was able to maintain good sharpness for a long time. Perforation efficiency is about 14
At 0 (mm / min), it was about 1.3 times that of the comparative product, and the life was about 10.1 m, which was about 3 times that of the comparative product. On the other hand, the comparative product does not have sufficient holding power for the abrasive grains, and some of the abrasive grains fall off during the drilling operation to reduce the drilling efficiency.
(Mm / min), and the life was about 3.2 m.

[0024]

According to the present invention, the following effects can be obtained.

(1) The distribution of the abrasive grains can be made uniform by arranging the abrasive grains in all the openings of the mesh body or in the openings at intervals. Also, by fixing the mesh and the abrasive grains to the base metal with a brazing material in a state where the abrasive grains are projected from the surface of the mesh body having an aperture smaller than the grain diameter of the abrasive grains, the abrasive grains have excellent holding power. A grinding wheel is obtained.

(2) The abrasion resistance of the brazing material can be increased by fixing the net-like body in the brazing material having low wear resistance.

(3) By setting the projection amount of the abrasive grains from the surface of the mesh within a specific range, the abrasive grains sufficiently dig into the material to be ground and are ground, and the chips are efficiently discharged. ,
Stable sharpness is obtained without clogging or seizure.

(4) By forming a plurality of abrasive layers composed of a mesh and abrasive grains, even if the outer layer abrasive grains are crushed, the abrasive grains in the inner layer protrude, so that the grinding is continued. It can be performed.

(5) By using a mesh made of titanium or a titanium alloy, the carbon in the abrasive grains reacts with the titanium in the mesh to produce titanium carbide, and a strong abrasive grain holding force is obtained. .

[Brief description of the drawings]

FIG. 1 is an overall perspective view of a core bit according to an embodiment of the present invention.

FIG. 2 is a partial longitudinal sectional view of the core bit shown in FIG.

FIG. 3 is a partial plan view showing an arrangement of abrasive grains in an abrasive layer.

FIG. 4 is a view showing a cross-sectional structure of an abrasive grain layer in another embodiment in which a network and an abrasive grain layer are formed in two layers.

[Explanation of symbols]

 Reference Signs List 10 core bit 11 boss 12 base metal 12a base 12b bulging part 13,23 abrasive layer 14,24 wire mesh 15 opening 16,26 abrasive 17 brazing material

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Seiya Ogata 210 Noritake Diamond Co., Ltd. F-term (reference) 3C063 AA02 BA31 BB02 BG01 BG16 BH05 FF22 FF23

Claims (4)

[Claims] 1. A grinding wheel using super-abrasive grains such as diamond or CBN, wherein the abrasive grains are arranged in all openings or spaced openings of a mesh having openings smaller than the grain size of the abrasive grains. A grinding wheel, characterized in that abrasive grains project from the surface of the mesh body, and the abrasive grains are fixed to the base metal with the mesh body and a brazing material. 2. The amount of protrusion of abrasive grains from the surface of the mesh body,
2. The grinding wheel according to claim 1, wherein the diameter is in the range of 1/5 to 1/2 of the grain size of the abrasive grains. 3. The grinding wheel according to claim 1, wherein a plurality of abrasive layers comprising the mesh and abrasive grains are formed. 4. The grinding wheel according to claim 1, wherein the mesh is titanium or a titanium alloy.