JP3664930B2 - Diamond tools for processing hard and brittle materials - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an improvement of a cylindrical diamond tool used for processing hard and brittle materials such as cemented carbide, glass and ceramics by various machine tools such as a jig grinder, a grinding center, and a general purpose / exclusive grinder.
[0002]
[Prior art]
Diamond tools are used to process hard and brittle materials. The diamond tool is generally formed by adhering diamond abrasive grains to a columnar or cylindrical main body (base metal) via an adhesive or by electrodeposition.
[0003]
[Problems to be solved by the invention]
In such side surface processing using a diamond tool, the processing liquid is not efficiently supplied to the processing point, and thus there is a problem that the processing speed cannot be increased due to insufficient cooling and lubrication, or the tool life is reduced. Further, in the drilling process in which a planetary motion is given to the diamond tool, the load of the diamond abrasive grains at the tool corner portion is increased, and the tool life is shortened due to falling off or wear of the abrasive grains. In addition, since the machining waste is not sufficiently discharged at the bottom surface of the tool, the machining waste is clogged between the diamond abrasive grains, resulting in a problem that machining cannot be continued.
[0004]
The problem to be solved by the present invention is to improve the working efficiency and extend the tool life in one-dimensional or two-dimensional side surface processing, three-dimensional shape processing and drilling processing in processing of hard and brittle materials. It is in.
[0005]
[Means for Solving the Problems]
The gist of the present invention is that a cylindrical tool body of a diamond tool for processing hard and brittle materials is (a) a torsion angle of 0 to 45 °, a rake angle of 0 to + 5 ° and a rake angle of 5 ° to 10 on the outer periphery. An outer peripheral cutting edge having an outer clearance angle of 3 ° and a margin width of 3 mm to 5 mm, (b) a corner cutting edge having a corner radius R = 1 mm to 3 mm at the corner, and (c) a rake of 0 to + 5 ° at the bottom. the bottom cutting edge and a margin width of the corner and 5 ° to 10 ° clearance angle and 2 mm to 4 mm, it characterized as having.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
The illustrated examples are all cylindrical diamond tools used for processing hard and brittle materials such as cemented carbide, glass, ceramics, etc., with various machine tools such as jig grinders, grinding centers, and general purpose / exclusive grinders. Indicates.
[0007]
1 and 2, reference numeral 1 denotes a tool body, 2 denotes a tool shaft, and the tool body is detachably attached to a spindle of a machine tool. 3 is an outer peripheral cutting edge provided on the outer periphery of the tool, and 4 is a diamond abrasive, which is bonded to the tool body and the outer peripheral blade via a known adhesive or by electrodeposition. A supply hole 5 communicates with the tool shaft 2 and opens at the bottom of the tool body. The supply hole 5 is provided in the center axis of the tool shaft 2 and the tool body 1, and a working fluid for cooling and lubrication is supplied through the supply hole. The
[0008]
As shown in FIG. 3, the outer peripheral cutting edge 3 has a twist angle of 0 to 45 °, a rake angle of 0 to + 5 °, a peripheral clearance angle of 5 ° to 10 °, and a margin width of 3 mm to 5 mm. Note that the flank width is 5 mm or more. These numbers and the following numbers are empirical values. 6 is a chip pocket, which is formed by providing an outer peripheral cutting edge.
[0009]
By providing the outer peripheral cutting edge 3, in the side surface processing, the diamond abrasive grains 4 and the cutting edge shape of the outer peripheral cutting edge combine to reduce the processing burden, and the chip pocket 6 is secured to discharge machining waste. Becomes easier. Further, as shown in FIG. 4, the machining fluid supplied from the outside of the tool is more effectively supplied to the machining point on the rake face of the outer peripheral blade.
[0010]
5 and 6 show an example in which a corner cutting edge 7 having a corner radius R = 1 mm to 3 mm is provided at a corner portion (lower end outer peripheral portion) of the tool body 1 provided with the outer peripheral cutting edge 3. By providing the corner cutting edge, the burden on the corner portion, which was large in the prior art, is dispersed, so the burden on the abrasive grain unit is reduced, and the falling off and wear of the abrasive grains are reduced. In the example of FIG. 4, the machining fluid supply hole 5 may be provided.
[0011]
7 and 8 show an example in which a bottom cutting edge 8 is provided at the bottom of the tool body 1 of FIG. The bottom cutting edge 8 has a rake angle of 0 to + 5 °, a clearance angle of 5 ° to 10 °, and a margin width of 2 mm to 4 mm. By providing the bottom cutting edge 8, the chip pocket 6 is secured and the machining waste can be easily discharged. Further, by supplying the machining fluid from the supply hole 5, the machining waste on the bottom surface of the tool body 1 is reduced. Clogging is reduced.
[0012]
The tool body 1 may be provided with only one cutting edge from among the outer peripheral cutting edge 3, the corner cutting edge 7, and the bottom cutting edge 8, and from the cutting edges 3, 7, 8 depending on the application. Two or three selected cutting edges may be provided. For example, when the outer peripheral cutting edge 3 and the bottom cutting edge 8 are provided, both side machining and drilling can be performed.
[0013]
Here, the diamond tool of the present invention provided with the outer peripheral cutting edge 3 shown in FIG. 1 and FIG. 2 is an example in which the tool life is improved compared with the conventional cylindrical diamond tool by side machining of cemented carbide. Show.
Tool rotation speed 12000 revolutions / minute feed rate 1000 mm / minute axial depth of cut 20 mm
Radial depth of cut 0.05mm
Under the above grinding conditions, the life grinding length of the conventional diamond tool was 3.6 m, while that of the present invention was 8 m.
[0014]
Further, as shown in FIG. 9, the resistance value corresponding to the 45th pass of the conventional diamond tool represented by a broken line and the resistance value of the 100th pass of the diamond tool of the present invention represented by the solid line are the same. Diamond tools have been demonstrated to have more than twice the life of conventional diamond tools.
[0015]
Next, the tool life comparison between the diamond tool of the present invention provided with the bottom cutting edge 8 and the conventional cylindrical diamond tool shown in FIGS. 7 and 8 is shown. Cutting conditions are
Tool rotation speed 14000 rotation / feed rate per minute 100mm / planetary radius 2mm per minute
The axial depth of cut is 0.05 mm / rotation, and the life processing depth is 10 mm for the diamond tool of the present invention, whereas the conventional diamond tool is 5 mm. As a result, it has been demonstrated that the diamond tool of the present invention has twice the life compared to conventional diamond tools.
[0016]
【The invention's effect】
By processing hard and brittle materials, it is possible to improve the processing efficiency and extend the tool life in one-dimensional or two-dimensional side surface processing, three-dimensional shape processing, and drilling processing.
[Brief description of the drawings]
FIG. 1 is a front view of a diamond tool provided with a peripheral cutting edge.
FIG. 2 is a cross-sectional view of FIG.
FIG. 3 is an enlarged view of a main part of FIG. 2;
FIG. 4 is a side view when supplying a processing liquid to a processing point.
FIG. 5 is a front view of a diamond tool provided with an outer peripheral cutting edge and a corner cutting edge.
FIG. 6 is an enlarged cross-sectional view of a main part showing a corner cutting edge.
FIG. 7 is a bottom view when a bottom cutting edge is provided.
FIG. 8 is an enlarged view of a bottom cutting edge.
FIG. 9 is a graph showing the life of a conventional diamond tool and a diamond tool of the present invention in side machining.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Tool body 3 Perimeter cutting edge 4 Diamond abrasive grain 5 Supply hole 7 Corner cutting edge 8 Bottom cutting edge

Claims (2)

The cylindrical tool body
An outer peripheral cutting edge having a torsion angle of 0 to 45 °, a rake angle of 0 to + 5 °, an outer clearance angle of 5 ° to 10 °, and a margin width of 3 mm to 5 mm on the outer periphery;
A corner cutting edge having a corner radius R = 1 mm to 3 mm at the corner, and
The bottom cutting edge and a margin width of flank angle and 2mm~4mm rake angle and 5 ° to 10 ° of 0 to + 5 ° to the bottom,
A diamond tool for processing a hard and brittle material, comprising:   The diamond tool for processing a hard and brittle material according to claim 1, wherein a supply hole for supplying a cooling / lubricating processing fluid that opens to a bottom portion in communication with the tool shaft is provided in the cylindrical tool body.

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