JPH04159083A - Rotary grinding tool - Google Patents

Abstract

PURPOSE:To provide excellent cutting capacity for a long period and to provide a sharply increased life by forming an axially extending plane at the tip of a shaft base body and adhering grinding materials to a plane in a manner that the grinding materials are axially interconnected. CONSTITUTION:Through rotation of a rotary grinding tool formed such that grinding materials 13 are adhered on the tip surface of a shaft base body 11, a work is ground by means of the grinding materials 13. In this case, an axially extending plane 12a is formed to the tip of the shaft base body 11, and the grinding materials 13 are adhered on the plane 12a in a manner that they are interconnected in an axial direction. Thus, when grinding grains 13 at the topmost tip effecting grinding through rotation of the shaft base body 11 are worn or dropped off, the tip of the shaft base body 11 is inversely ground by a work. Thereby, the grinding grains 13 subsequent to the grinding grains at the topmost tip is functioned as a cutting edge in way that they are protruded from the tip of the shaft base body 11, and grinding can be consecutively executed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a rotary grinding tool having an abrasive material such as diamond grains attached to the tip of a shaft base.

(Prior Art) This type of tool is used for drilling holes in hard materials such as ceramics. The conventional one uses abrasive grains 1, such as diamond grains, as the abrasive material, and has a structure in which the abrasive grains 1, such as diamond grains, are attached to the tip surface of a shaft base body 2 having a thin cylindrical shape, as shown in FIG. One group of these abrasive grains adheres to the surface of the shaft base 2 by one layer, and is fixed to the shaft base 2 by the nickel plating layer 3. By pressing the tip against the workpiece while rotating the shaft base body 2, the abrasive grains 1 can grind the workpiece and make a hole in the workpiece.

(Problem to be solved by the invention) However, conventional tools of this type have had a problem of short life. When drilling a hole in a workpiece by rotating a tool having the structure shown in FIG. 12 while applying ultrasonic vibrations up and down, the abrasive grains 1 in the center of rotation are worn out, as shown in FIG. 13. This results in severe wear and loss of grinding ability. Furthermore, if a large load is applied to the abrasive grains 1, the abrasive grains 1 will fall off early, as shown in FIG. 14, and the grinding ability will be rapidly lost.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a rotary grinding tool that can have a long service life.

[Structure of the Invention] (Means for Solving the Problems) The rotary grinding tool of the present invention has an abrasive material attached to the tip surface of a shaft base, and grinds a workpiece with the abrasive material by rotating the tool. , is characterized in that a flat surface extending in the axial direction is formed at the tip of the shaft base, and the abrasive material is attached to the flat surface so as to be continuous in the axial direction.

(Function) According to the above embodiment, the abrasive material is attached to the plane formed at the tip of the shaft base in a continuous manner in the axial direction. For this reason,
For example, if the abrasive material is abrasive grains such as diamond grains,
A large number of abrasive grains are arranged in the remaining film in the axial direction. Therefore, if the cutting edge abrasive grain wears out or falls off while the shaft base is being rotated and polished, the tip of the shaft base will be ground by the workpiece, and the next abrasive grain will be removed from the shaft. It protrudes from the tip of the base body and functions as a cutting edge so that grinding can continue. The abrasive material may be not only abrasive grains such as diamond or CBN, but also a sintered body such as CBN or cermet, or a hard film such as gas-phase diamond. If the abrasive grains are formed in a continuous manner in the same direction, as the abrasive material at the tip wears down, the next new abrasive material will contribute to grinding, and the same effect as that of diamond abrasive grains can be obtained.

(Embodiment) 1> A first embodiment of the present invention will be described with reference to FIGS. 1 to 3.

As shown in FIG. 3, the overall shape of the shaft base 11 is cylindrical, and the base side is thicker and the tip side is tapered in a stepped manner. A semicircular cross section 12 is provided at the tip by removing the vertical half by cutting, and a flat surface 12a extending in the axial direction is formed there. This plane 12a
As an abrasive material, abrasive grains 13 of, for example, diamond grains are adhered to the shaft base 11 so as to be closely continuous in the axial direction of the shaft base 11, and these are fixed to the shaft base 11 by an electrodeposited layer 14 formed by nickel plating. In addition, in this way, plane 1
A surface formed by a group of 13 abrasive grains fixed to one surface of 2a is located so as to include the center of rotation of the shaft base 11. Further, as a method for fixing the abrasive grains 13 to the shaft base 11, a well-known electrodeposition method can be adopted. For example, a flat surface 12 extending in the axial direction located at a semicircular cross section 12 of the shaft base 11
After masking the parts other than a, the shaft base 11
Insert the tip of the abrasive grains 13 into the storage part and
The abrasive grains 13 may be attached to the surface, and nickel plating may be applied in this state to fix the abrasive grains 13.

When drilling a hole in a workpiece such as a ceramic using the above-described tool, the tool is rotated while vertically applying ultrasonic vibration to the shaft base 11, and the tip is pressed against the workpiece, as in the conventional tool. Then, the 13 rows of abrasive grains located at the leading edge rotate while vibrating up and down on the surface of the workpiece, so that the workpiece is ground and a hole with an inner diameter approximately equal to the diameter of the semicircular cross-sectional portion 12 of the shaft base 11 is bored. . When such grinding is performed many times, the 13 rows of abrasive grains located at the leading edge gradually wear out, and as a result, the tip surface of the semicircular section 12 of the shaft base 11 comes to rub directly against the workpiece. . Then, the tip end surface wears out and retreats from its initial position as shown by the dashed line in FIG. The abrasive grains 13 protrude from the tip surface of the circular portion 12, and the 13 rows of abrasive grains function as cutting edges to continue grinding the workpiece.

Furthermore, when this 13 rows of abrasive grains are worn out, the next 13 rows of abrasive grains come to contribute to grinding, as described above, and new abrasive grains 13 come to function as cutting edges one after another. In the end, the grinding ability is maintained until the 13 rows of residual abrasive grains connected in the axial direction are worn out, dramatically extending the lifespan of conventional rotary grinding tools in which only one row of abrasive grains contributes to grinding. It can be extended. Furthermore, in the past, when an excessive load was applied to the tool, the abrasive grains 1 often fell off from the tip of the shaft base 2 as described above, but according to this embodiment, the abrasive grains 13 are removed in the axial direction. Since the abrasive grains 13 are fixed to the flat surface 12a extending in the direction of
Half of the group will receive a force in the direction of being pressed against the plane 12a. Therefore, the abrasive grains 13 are less likely to fall off, which also contributes to longer life.

2> A second embodiment of the present invention will be described with reference to FIGS. 4 and 5. In order to avoid duplication of explanation, the same parts as in the first embodiment are given the same reference numerals, and differences will be mainly described. In this embodiment, the plane extending in the axial direction to be formed in the shaft system 11 is such that a groove 21 is formed at the tip of the shaft system 11, and one surface of the groove 21 is formed in the axial direction for attaching the abrasive grains 13. The plane 21a extends to .

3> FIGS. 6 and 7 show a third embodiment of the present invention. Again, in order to avoid duplication of explanation, the same parts as in the second embodiment are given the same reference numerals, and differences will be mainly described. In this embodiment as well, a flat surface 21a is formed in the same manner as in the second embodiment, and the abrasive grains 13 are fixed thereto by an electrodeposited layer 14. Then, the remaining space of the groove 21 is filled with an adhesive 22 containing metal powder, thereby increasing the rigidity of the tool tip.

4> FIGS. 8 and 9 show a fourth embodiment of the present invention.

Again, in order to avoid duplication of explanation, the same parts as in the third embodiment are given the same reference numerals, and differences will be mainly described. The difference from the third embodiment is that the grooves 31 are formed in a cross shape, and the abrasive grains 13 are fixed to a flat surface 31a extending in the axial direction to form the grooves 31 by an electrodeposited layer 14. The third embodiment is similar to the third embodiment in that the remaining space of the groove 31 is filled with adhesive 22 containing metal powder.

5> FIGS. 10 and 11 show a fifth embodiment of the present invention. Again, in order to avoid duplication of explanation, the same parts as in the first embodiment are given the same reference numerals, and differences will be mainly described. The difference from the first embodiment is that instead of the abrasive grains 13, TiC or T
The abrasive material layer 41 is formed by coating with iN or the like.

Even in this configuration, since the abrasive material layers 41 are continuous in the axial direction, it is possible to extend the life as in the first embodiment.

6) In addition, the present invention can be applied to any type of abrasive material and the material of the shaft system, such as using super abrasive grains such as CBN or their sintered bodies, or using a vapor-phase diamond film. It doesn't matter. Further, the abrasive material may be attached not only to the plane extending in the axial direction but also to the entire tip of the shaft system body, and the ultrasonic vibration may be applied as necessary, etc., without departing from the gist of the present invention. This can be implemented with various modifications.

[Effects of the Invention] As described above, according to the rotary grinding tool of the present invention, even if the abrasive material wears out, new abrasive material can function as a cutting edge one after another, so excellent grinding can be achieved over a long period of time. This has the effect of making it possible to demonstrate the ability and dramatically extend the lifespan.

[Brief explanation of the drawing]

1 to 3 show a first embodiment of the present invention.
The figure is a side view of the main part, FIG. 2 is a plan view of the main part, and FIG. 3 is a perspective view of the whole. 4 and 5 are views corresponding to FIGS. 1 and 2 showing a second embodiment of the present invention, and FIGS. 6 and 7 are views corresponding to FIGS. 1 and 2 showing a third embodiment of the present invention. Figure equivalent diagram,
8 and 9 are views corresponding to FIGS. 1 and 2 showing the fourth embodiment of the present invention, and FIGS. 10 and 11 are views corresponding to the fifth embodiment of the present invention.
FIG. 1 is a diagram corresponding to FIG. 1 and FIG. 2 showing an embodiment. FIGS. 12 to 14 are sectional views of main parts of a conventional rotary grinding tool. In the figure, 11 is a shaft system body, 12a, 21a, and 31a are planes extending in the axial direction, 13 is an abrasive grain (abrasive material), and 41 is an abrasive material layer (abrasive material). Agent Patent Attorney Tsuyoshi Sato Figure 1 Figure 1 S Figure 2 Figure 3 Figure M4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 13 Figure 2a Figure 11 2 Akira Ku 14 Figure

Claims (1)

[Claims] 1. An abrasive material is attached to the tip surface of a shaft base, and a workpiece is ground by rotating the abrasive material, in which a plane extending in the axial direction is formed at the tip of the shaft base, and the abrasive material is attached to the top surface of the shaft base. A rotary grinding tool characterized by having abrasive material attached in a continuous manner in the axial direction.