JPH05337722A - Rotary tool - Google Patents

Abstract

PURPOSE:To make accurate shape forming such as gradation, chamfering or the like along a reference finishing surface form easily machinable in a separate process from reference finish surfacing work by installing a journal bearing in the tip of a cutting edge. CONSTITUTION:When spiral chamfering is performed, a tool is chucked to a milling machine and then an outer circumference of a ball bearing 3 is pushed to a side wall 5 serving as a reference finishing surface of a workpiece 4. At this time, a height direction of the tool should be set according to a chamfering quantity. In this state, if the tool is traveled along the side wall 5 as rotating it, accurate chamfering is automatically formed along the side wall 5 by a cutting edge 1. In this case, the workpiece 4 may be moved instead of moving the tool.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention is generally used in milling.

[0002]

2. Description of the Related Art FIG. 4 shows a sectional view of a conventional rotary tool for milling. These tools generally consist of a shank part 2 fixed to the machine tool and a cutting edge 1 for machining the workpiece 4. When chamfering in a shape along the reference finishing surface 5 with a conventional rotary tool as shown in the figure and forming a paragraph, etc., perform additional machining while fixing the finishing surface on the machined equipment, or It was necessary to position and fix the work piece to another equipment with high precision, and machine it with equipment having NC control or a profile processing device.

[0003]

However, according to the above-mentioned method with the conventional rotary tool, for example, as shown in FIG. 3, the intersection 6 between the upper surface 7 and the side surface 5 of the spiral wall is chamfered with high accuracy. When processing and removing, it is necessary to chamfer without removing the chuck after finishing the wall surface with the same equipment as the finishing processing of the upper and side surfaces of the spiral wall, which increases the processing time, enlarges the equipment, and increases the equipment cost. It was necessary to improve accuracy.
There is also a method of simultaneously machining the wall surface and chamfering with a tool with a chamfering blade for the wall surface finishing tool, but if the required dimensional accuracy is strict, the tool fabrication is difficult and the desired tool shape cannot be obtained. Therefore, it was difficult to obtain high dimensional accuracy. When chamfering is performed in a separate step, re-chuck causes angular deviation / center deviation from the spiral shape, making it difficult to obtain a uniform and highly accurate chamfered shape. In order to obtain a uniform and highly accurate chamfered shape, it is necessary to accurately position and fix the workpiece, and it is necessary to improve the accuracy of the equipment, which requires a long time for installation and causes a cost increase.

The present invention is intended to solve the above-mentioned problems of the conventional example, and an object thereof is to easily process even a complicated shape when processing a shape along a finished surface. ..

[0005]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a rotatable journal bearing at the tip of a cutting blade. Particularly for chamfering, a cutting edge surface having an angle with respect to the tool axis is formed, and a rotatable journal bearing is provided at the tip thereof.

[0006]

According to the present invention, since the rotary tool having the above-mentioned structure is pressed against the finish surface which becomes the reference in the vicinity of the portion where the rotatable journal bearing is to be processed and is subjected to the milling processing, the reference finish surface is used. The shape can be easily shaped and processed with high precision.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a sectional view of a rotary tool provided with a journal bearing, and in the case of machining, FIG. 2 is a sectional view of a rotary chamfering tool provided with a journal bearing.

FIG. 1 shows a tool for forming a surface 6 in which a workpiece 4 is divided into a reference finished surface 5 by a predetermined amount δ. A shank portion 2 has a cylindrical cutting edge 1 at the tip thereof, and further a cutting edge. There is a boss 8 coaxial with the shank portion 2 at the end of 1.
The inner ring of the ball bearing is inserted into and fixedly attached to form a rotatable journal bearing 3. The cutting edge diameter is larger than the outer diameter of the ball bearing by the amount corresponding to the set depth of cut δ. If this tool is chucked on a milling machine and moved while pressing the outer circumference of the ball bearing against the reference finishing side surface 5 of the workpiece 4, the surface 6 which is a certain amount δ from the reference side surface 5 is accurate along the reference side surface. Well shaped. Since the outer circumference of the ball bearing 3 moves while pressing against the reference surface 5, even if the cutting edge 1 of the tool is rotated at several thousand revolutions per minute, the ball bearing outer circumference is in a rolling state with respect to the reference surface due to the rotatable structure. Even if the workpiece is brought into contact with each other and pressed with a relatively large force, the reference finish surface 5 of the workpiece is not damaged.

FIG. 2 shows that the workpiece 4 is chamfered along the reference finish surface 6 at the intersection with the upper end surface 7 with high accuracy (for example, the chamfering amount is 0.05 to 0.15 mm at an angle α). It is a tool, and the shank part 2
The cutting edge 1 is arranged at the tip of the cutting edge 1 and the cutting edge 1 has a predetermined chamfering angle α.
It is shaped like a cone with. Further, there is a boss 8 coaxial with the shank portion 2 at the tip of the cutting edge 1, and an inner ring of a ball bearing is inserted and fixed to the boss portion 8 to form a rotatable journal bearing 3.

As an example, FIG. 3 shows a spiral chamfering process which is carried out by using the rotary chamfering tool of the present invention. Workpiece 4 is chucked with the tool on a milling machine.
The outer periphery of the ball bearing 3 is pressed against the side wall 5 which is the reference finish surface of. Set the height direction of the tool according to the chamfering amount. If the tool is moved along the side wall 5 while rotating the tool in this state, a chamfer with high precision is automatically formed along the side wall 5. In this case, the workpiece 4 may be moved instead of moving the tool. Also in this case, similarly to the case of the paragraph in FIG. 1, due to the action of the rotatable journal bearing, it is possible to press with a proper force without damaging the finished surface of the workpiece. Further, as a method for fixing the cutting edge 1 to the shank portion 2, only the cutting edge 1 is made of carbide or other high precision tool material, and each is fixed by screwing or brazing,
A rotary tool or a chamfering tool having a journal bearing at its tip is conceivable, and can be produced relatively inexpensively.

[0011]

As is apparent from the above description, according to the present invention, by providing the journal bearing at the tip of the cutting edge, the accurate finish forming such as step drop and chamfering along the reference finished surface shape can be performed as the standard finish. It can be easily processed in a separate process from the surface processing. Therefore, it is not necessary to use a high-precision machine tool, nor is it necessary to perform high-precision positioning, which results in inexpensive machining. Further, there is no fear of damage to the reference work surface due to the profile work, and various effects are exhibited such that the tool to be used can be made relatively inexpensive.

[Brief description of drawings]

FIG. 1 is a sectional view of a rotary tool showing an embodiment of the invention.

FIG. 2 is a sectional view of a rotary chamfering tool showing an embodiment of the invention.

FIG. 3 is a perspective view showing a spiral chamfering processing state in which the rotary chamfering tool of the present invention is used for processing.

FIG. 4 is a sectional view of a conventional tool for making a paragraph.

[Explanation of symbols]

 1 Cutting edge 2 Shank part 3 Journal bearing

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshimi Yotsuya 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (6)

[Claims] 1. A rotary tool in which a rotatable journal bearing is provided at the tip of a cutting blade. 2. The rotary tool according to claim 1, wherein the rotary tool is an end mill. 3. The rotary tool according to claim 1, wherein the outer diameter of the journal bearing is the same as or smaller than the outer shape of the cutting edge of the rotary tool. 4. A rotary chamfering tool provided with a rotatable journal bearing at the tip of a cutting edge, the cutting edge having an angle with respect to the tool axis. 5. The rotary chamfering tool is an end mill.
Rotary chamfering tool. 6. The rotary chamfering tool according to claim 4, wherein the outer diameter of the journal bearing is equal to or smaller than the diameter of the cutting edge of the rotary chamfering tool.