JPH10277814A - Rotary cutting tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a rotary cutting tool to machine a workpiece without entailing any damage to the finished surface upon preventing chips from biting into a space between a tip and the workpiece by installing a bite preventing means in the point of a cutting tool body. SOLUTION: A bite preventing means 31 is integrally formed together with a shore part 31A to be erected on top of a cutting tool body 11 in a cantilevering state at an upper end of this shore part 31A while it is equipped with a platelike shielding part 31B where its point projecting toward a tip 25, and it is attached to a top face of the cutting tool body 11. Even in the case where chips produced out of a workpiece W are not cut short, and extended so as to get into a clearance part 33 where the rotating tip 25 and a peripheral surface of the workpiece W come nearer to each other, the chips are incapable of getting into the clearance part 33 as being hindered by the shielding part 31B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary cutting tool in which a disc-shaped throw-away tip (hereinafter referred to as a tip) is rotatably mounted on the tip of a cutting tool body around its axis. The present invention relates to a rotary tool that is effective for preventing chips from being caught between a work material and a chip.

[0002]

2. Description of the Related Art With respect to this kind of rotary tool, the present inventors have proposed a rotary tool as shown in FIG. 6 in Japanese Patent Application No. 8-273844. This rotary tool is a tip 1 of the tool body 1
A, a substantially cylindrical sheet member 3 is provided in a blind hole-shaped mounting hole 2 formed obliquely from the upper surface to the lower surface thereof so as to be rotatable around its central axis O.
A disc-shaped chip 5 is detachably attached to the tip of the device via a chip attachment member 4.

In the rotary cutting tool having such a structure, the work piece W is rotated while the tip 5 is rotated.
The chip 5, the chip mounting member 4, and the sheet member 3 are cut by the circumferential cutting blade 5A formed in
However, cutting is performed while integrally rotating about the axis O.

[0004]

However, in the rotary cutting tool having the above-described structure, the chips shaved from the work material W are continuously flowed without being divided into short pieces, and continuously flow. The rotating work material W and the outer peripheral surface of the tip 2 may enter the gap 6 approaching each other. In such a case, since the chip 5 and the work material W are both rotating in the direction in which the chips are wound into the depth of the gap 6 in the gap 6, the cutting that has entered the gap 6 is performed. There is a problem that the debris is caught between the work material W and the chip 2 and the finished surface W1 of the work material W is scratched.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a rotary cutting tool capable of effectively preventing chips from being caught between a work material and a chip.

[0006]

Means for Solving the Problems In order to solve the above-mentioned problems and achieve the object, a rotary cutting tool according to the present invention comprises
At the tip of the tool body, a disk-shaped chip with a circular cutting edge formed at the intersection ridge line between the upper surface forming the rake surface and the outer peripheral surface forming the flank is rotatably mounted around its axis. In the rotary bite, the tip of the bite body is provided with a biting prevention means for preventing chips from entering a gap where the outer peripheral surfaces of the rotating tip and the work material approach each other. It is a feature.

[0007] With this configuration, it is possible to prevent chips from being caught between the chip and the work material, so that cutting can be performed without scratching the finished surface of the work material. Can be.

According to a second aspect of the present invention, there is provided a rotary tool according to the first aspect, wherein the bite preventing means includes a support provided on an end of the tool main body and a support provided from the support. A shielding portion protruding toward the chip so as to shield the upper part of the gap portion, wherein the shielding portion has a circular arc-shaped notch formed along a flank of the chip at a tip portion. Is what you do.

In such a configuration, even if the chips extend into the gap while curling without being divided into short pieces, the chips may enter the gap due to the obstruction of the shielding portion. It is not possible to prevent the workpiece from being caught between the work material and the chip, so that cutting can be performed without scratching the finished surface of the work material. Also,
When the curled chips hit the shielding portion, the chips are broken on the way and are divided into short pieces, so that the chips can be discharged smoothly.

A rotary tool according to a third aspect of the present invention is the rotary tool according to the second aspect, wherein the gap between the inner peripheral surface of the notch of the shielding portion and the flank of the chip is different from each other.
It is characterized by being set to 0.05 mm to 0.1 mm.

With this configuration, chips can be prevented from entering the gap from the gap between the tip of the shielding portion and the flank of the chip, and smooth rotation of the chip can be maintained. Good cutting can be performed.

According to a fourth aspect of the present invention, there is provided a rotary tool according to the second or third aspect, wherein a side surface of the shield portion facing the work material and a center of rotation of the tip are provided. The mutual spacing in the cutting direction with the cutting edge most separated in the cutting direction from 0.1 mm ~
It is characterized by being set to 0.5 mm.

[0013] With such a configuration, chips are prevented from entering the gap from the gap between the work material and the side surface of the shielding portion facing the work material, and at the same time, the size of the work material is reduced. Interference between the finished surface and the shielding portion can be prevented, so that not only scratches due to biting of chips but also scratches due to interference can be prevented.

According to a fifth aspect of the present invention, there is provided a rotary tool according to any one of the first to fourth aspects, wherein a welding-preventing means is provided at a tip end portion of the tool body for removing a deposit attached to the chip. Is provided.

[0015] In the case of such a configuration, even if the cuttings shaved from the work material are welded to the chip, the welded material is removed to generate scratches on the finished surface of the work material, A reduction in processing accuracy can be prevented.

According to a sixth aspect of the present invention, in the rotary tool according to the fifth aspect, the welding prevention means is a protruding portion that protrudes from a tip of the shielding portion and is disposed above the cutting blade. It is characterized by having.

In such a configuration, even when the chips shaved from the work material are welded to the chip and the welded material adheres, the welded material is rotated by the rotation of the chip during cutting. Since it can be dropped against the side surface of the protruding portion of the shielding portion, it is possible to prevent generation of scratches on the finished surface of the work material due to the welded material and reduction in processing accuracy.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS.
A first embodiment of the present invention will be described. In the present embodiment, as shown in FIG. 3, a blind hole-shaped mounting hole 13 is formed in the tip end portion 12 of the cutting tool body 11 from the upper surface to the lower surface thereof. A bearing member 14 having a flange shape whose tip (upper end) portion 14A is one step larger in diameter than the cylindrical body portion 14B is fitted and inserted.

The bearing member 14 has a concave portion 1 in a body portion 14B.
4C, the tip of a fixed piece 15 inserted into a through hole 12A formed at the tip 12 of the cutting tool body 11 so as to open at the position of the recess 14C.
It is fixed to the mounting hole 13 by engaging with 4C.

The radial bearing 1 is provided on the inner periphery of the bearing member 14.
6, a substantially columnar sheet member 17 whose front end (upper end) portion 17A is enlarged by one step is attached by inserting the columnar shaft portion 17B, and the bearing member 14 is attached thereto.
The upper surface of the front end portion 14A and the front end portion 17 of the sheet member 17
A thrust bearings 18 are interposed between the lower surface of A and
The seat members 17 are formed by these bearings 16.
Is rotatably supported about its central axis O.

At the rear end 17C of the sheet member 17,
A disc-shaped receiving plate 19 is attached to the tip portion 17A side by clamp screws 21 and 21 with a thrust ball bearing 20 interposed therebetween, and attached to the thrust ball bearing 20 and the rear end opening of the bearing member 14. The disc spring 23 is interposed between the disc spring 23 and the annular disc spring receiving member 22 in a compressed state. Along with 19, it is urged toward the rear end side in the axis O direction.

On the other hand, a substantially disk-shaped chip 25 penetrates the tip 25A of the sheet member 17 via a chip mounting member 24 having a substantially bottomed annular shape at the front end portion 17A of the sheet member 17. It is detachably mounted by a clamp screw 26 screwed into the sheet member 17.

The tip 25 is made of, for example, a hard material such as a cemented carbide, and one of the circular upper and lower surfaces is a rake face 27 and the outer peripheral face is a flank face 28. A circular cutting edge 25A is formed at the intersection ridgeline between the flank 28 and the rake face 27. Also,
A groove-shaped chip breaker 25B is formed on the outer peripheral edge of the upper and lower surfaces of the chip 25 so as to orbit along the cutting edge 25A.

Further, a mounting hole 12C is formed in the tip end portion 12 of the cutting tool body 11 from the upper surface 12B through a through hole 1C formed in the body portion 14B of the bearing member 14 through an oil passage 12D.
4D, the mounting holes 12 are formed.
C from the grease nipple 29 attached to the oil passage 1
Lubricating oil is supplied between the bearing member 14 and the shaft portion 17B of the seat member 17 through the 2D and the through hole 14D.

The upper surface 12B of the cutting tool body 11
Is fitted with anti-jamming means 31. The anti-jamming means 31 in the present embodiment includes a column 31A which is provided upright on the upper surface 12B of the cutting tool body 11, and is integrally formed in a cantilever state at the upper end of the column 31A, and the tip is formed as described above. An upper surface of the cutting tool body 11 is formed by bolts 32, 32 having a substantially L-shaped cross section including a plate-shaped shielding portion 31B protruding toward the chip 25, and penetrating the support portion 31A in the length direction. 12
B attached.

As shown in FIG. 4, a notch N having a concave arc shape in plan view along the flank of the chip 25 is formed at the tip of the shielding portion 31B. The inner surface of N and the clearance 28 between the flank 28 of the chip 25 are set to 0.05 mm to 0.1 mm, and the side surface F of the shielding portion 31B on the side facing the work material W. ,
The cutting tool is set so that the mutual interval L2 in the cutting direction d from the position P farthest in the cutting direction d from the rotation center C on the cutting edge 25A of the tip 25 is set to 0.1 mm to 0.5 mm. It is attached to the upper surface 12B of the main body 11. Further, the upper surface of the shielding portion 31B is set so as to be flush with the cutting blade 25A.

The reason why these mutual intervals L1 and L2 are set in the above range is as follows. That is, L1 is 0.1 m
If it is larger than m, the chips are cutouts N of the shielding portion 31B,
It becomes easy to enter the gap 33 through the gap between the flank 28 of the tip 25A and the chip 25A may not be effectively prevented from being caught by the chip 25A.
If it is smaller, the chip 25A interferes with the chip 25A.
This is because the smooth rotation of A may be hindered and the processing accuracy may be reduced.

If L2 is larger than 0.5 mm, chips enter the gap 33 through the gap between the side face F of the shielding portion 31B facing the work W and the work W. This makes it difficult to effectively prevent chips from being caught. When the thickness is smaller than 0.1 mm, the finished surface W1 of the work material W and the shielding portion 31B interfere with each other and the finished surface W1 This is because there is a possibility that the surface may be scratched.

In the rotary cutting tool having such a configuration, the chips shaved from the work material W are not divided shortly, and the rotating tip 25 and the outer peripheral surfaces of the work material W approach each other. Even if it extends so as to enter the gap 33, it cannot enter the gap 33 because it is obstructed by the shielding portion 31 </ b> B.

Therefore, chips are not caught between the workpiece W and the chip 25, and cutting can be performed without scratching the finished surface W1. In addition, when the curled chips hit the shielding portion 31B, the chips are broken on the way and are divided into short pieces.
Chips can be discharged smoothly.

Further, chips are generated at the intervals L1, L2.
The chip 25 is prevented from entering the gap 33 from the
Smooth rotation is maintained and cutting with high machining accuracy is enabled, and interference between the finished surface W1 of the work material W and the shielding portion 31B can be prevented. And the occurrence of scratches due to interference can be eliminated.

Next, a second embodiment of the present invention will be described with reference to FIG. The rotary cutting tool according to the present embodiment includes a shielding portion 31 of the biting prevention means 31.
Except that the cross-sectional shape of B is different, it has the same configuration as the rotary tool in the above-described first embodiment, and hence only the shielding portion will be described below.

The biting prevention means 41 in this embodiment
Is formed integrally in a cantilever manner at the upper end of a column 41A attached to the upper surface 12B of the cutting tool main body 11 with bolts 42, 42. In common, the protruding portion 41C protruding toward the center of rotation C of the tip 25 has a cutting edge such that a mutual interval L3 in the direction of the axis O with the cutting edge 25A is 0.05 mm to 0.1 mm. 25A
And that it is arranged above the chip breaker 25B.

In the case of such a configuration, the work material W
Chips that have been cut from
Even if the welded material 43 adheres to the surface, the welded material 43 can be dropped on the side surface f of the protruding portion of the shielding portion 31 by rotating the chip 25 at the time of cutting.
It is possible to prevent generation of scratches on the finished surface W1 of the work material W due to the welded material 43 and a decrease in processing accuracy.

In each of the above embodiments, as the anti-jamming means 31, 41, one in which the support portions 31A, 41A and the shielding portions 31B, 41B are integrally formed has been described. , 41A and the shielding portions 31B, 41B may be configured separately.

[0036]

As is clear from the above description, according to the present invention, the following effects can be obtained. (A) In the rotary tool according to the first aspect, since the bite preventing means is provided at the tip of the bite body, biting of chips between the tip and the work material can be prevented. Cutting can be performed without scratching the finished surface of the work material, and the accuracy of the finished surface can be improved.

(B) In the rotary cutting tool according to the second aspect, the bite preventing means is provided with a column standing upright at the tip of the bit body, and the outer periphery of the tip and the work material rotated from the column. A shielding portion protruding toward the chip so as to shield the upper side of the gap portion where the surfaces approach each other, and further, an arc-shaped notch is formed at the tip of the shielding portion along the flank of the chip. As a result, the chips cannot be hindered by the shielding portion and enter the gap, and the chips do not get caught between the work material and the chip, so that the finished surface of the work material is scratched. The cutting can be performed without adding a mark.

(C) Further, when the curled chips hit the shielding portion, the chips are broken on the way and cut short.
Chips can be discharged smoothly.

(D) In the rotary cutting tool according to the third aspect, the mutual interval between the notch inner peripheral surface of the shielding portion and the flank of the chip is set to be 0.05 mm to 0.1 mm. It is possible to prevent chips from entering the gap from the gap between the tip of the shielding portion and the flank of the chip, maintain smooth rotation of the chip, and perform cutting with high machining accuracy.

(E) In the rotary cutting tool according to the fourth aspect, the side surface of the shielding portion facing the work material and the cutting edge most separated in the cutting direction from the rotation center of the tip. By setting the mutual interval in the direction to be 0.1 mm to 0.5 mm, chips enter the gap from the gap between the work material and the side surface of the shielding portion facing the work material. Can be prevented, and interference between the finished surface of the work material and the shielding portion can be prevented, so that not only scratches due to chips but also scratches due to the interference can be prevented.

(F) In the rotary cutting tool according to the fifth aspect, the tip of the cutting tool body is provided with a welding prevention means for removing the deposited material attached to the chip, so that the cutting tool is cut out from the work material. Even if the cutting chips are welded to the chip, the welded material is removed, and it is possible to prevent generation of scratches on the finished surface of the work material due to the welded material and reduction in processing accuracy.

(G) In the rotary cutting tool according to the sixth aspect, the projecting portion disposed above the cutting edge of the tip is provided at the tip of the shielding portion, so that the cutting cut out from the work material. Even when the powder is welded to the chip and the deposited material adheres, the deposited material can be dropped against the side surface of the projecting portion of the shielding portion by rotating the chip during cutting,
Occurrence of flaws on the finished surface of the work material due to welding,
A reduction in processing accuracy can be prevented.

[Brief description of the drawings]

FIG. 1 is a plan view showing a state in which a work material is being cut by a rotary tool according to a first embodiment of the present invention.

FIG. 2 is a side view of FIG.

FIG. 3 is a sectional view showing a main part of the rotary tool.

FIG. 4 is a plan view of a main part of the rotary tool viewed from an axial direction of a chip.

FIG. 5 is a cross-sectional view illustrating a main part of a rotary tool according to a second embodiment of the present invention.

FIG. 6 is a plan view showing a state in which a work material is being cut by an example of a conventional rotary tool.

[Explanation of symbols]

 Reference Signs List 11 Tool body 12 Tip part 25 Tip (throw-away tip) 25A Cutting edge 27 Rake surface (upper surface) 28 Relief surface (outer peripheral surface) 31, 41 Biting prevention means 31A, 41A Column 31B, 41B Shield 33 Gap 41C Projecting part 43 Welding material C Center of rotation L1, L2 Spacing N Notch O Axis line W Work material d Cutting direction

Claims (6)

[Claims] 1. A disc-shaped throw-away tip having a circular cutting edge formed at a crossing ridge portion between an upper surface forming a rake face and an outer peripheral surface forming a flank at a tip end portion of a cutting tool body. In a rotary tool rotatably mounted, biting prevention for preventing chips from entering a gap where the outer peripheral surfaces of the rotating throw-away tip and the work material approach each other at a tip end of the tool body. A rotary cutting tool characterized by being provided with means. 2. The bite prevention means protrudes toward the throw-away tip so as to shield a portion above the gap portion from a support portion erected at a tip end portion of the cutting tool main body. The rotary cutting tool according to claim 1, further comprising a shielding part, wherein the shielding part has a circular arc-shaped notch formed along a flank of the throw-away tip at a tip end. 3. The distance between the inner peripheral surface of the notch of the shielding portion and the flank of the throw-away tip is 0.05 mm or more.
3. The rotary cutting tool according to claim 2, wherein the diameter is set to 0.1 mm. 4. A mutual interval in the cutting direction between a side surface of the shielding portion facing the work material and a cutting edge furthest away from a rotation center of the throw-away tip in the cutting direction is 0. The rotary tool according to claim 2, wherein the diameter is set to 1 mm to 0.5 mm. 5. The rotary tool according to claim 1, wherein a welding prevention means is provided at a tip end portion of the tool body for removing a welded matter attached to the throw-away tip. A rotary bite characterized by: 6. The rotary cutting tool according to claim 5, wherein the welding prevention means is a protrusion protruding from a distal end of the shielding portion and disposed above the cutting blade.