JPS6039007A - Annular edge tool - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to an annular cutter for forming holes in a workpiece.

Common problems with annular cutters include wear and chipping of the radially inner edges of the cutting teeth. This problem is caused by the inner circumferential surface of the tooth section and the inside of the workpiece being cut by the blade during cutting. It is thought that this is caused by metal chips frequently getting stuck between the outer circumferential surfaces of the disks &19.

These chips gradually increase and appear on the inner circumferential surface of the cutter near the tip edge of the cutter. If the metal is immersed in oil on the inner circumferential surface of the teeth, it will cause significant wear, resulting in an increase in the torque required to rotate the blade. In addition, not only is heat generation further accelerated, but wear becomes excessive, and function stoppage due to chipping or breakage is accelerated. Similarly, the chips that accumulate on the inner circumferential surface of all objects cause radial carts on the blade,
This results in the formation of additional holes, resulting in poor finish and easy damage. Therefore, it can be seen that by minimizing friction and effectively cooling the cutting edge, the life of the cutting tool will be extended.

An object of the present invention is to solve the problems of wear, chipping, heat conduction, and damage caused by accumulation of chips around the inner peripheral surface of a cutter.

A particular object of the present invention is to form an annular cutter so that surface contact of the inner circumferential surface of the cutter with the central disc portion which is being formed by the cutter is minimized at the corners.

Another object of the invention is to provide a large volume coolant passage directly adjacent the blade teeth.

The features and advantages of the song of the invention will become apparent from the following description and description of the aspects.

In the drawings, a sword according to the invention is generally designated by the reference numeral 10. The cutter 10 has a shank 12 at its upper end, from which an annular side wall 14 extends downwardly. A plurality of cutting teeth 16 are formed at the lower end of this side wall 14 and are spaced apart in the circumferential direction, while a spiral groove 18 is formed upwardly on the side wall 14 and the number of the teeth 16 is equal to or smaller than the teeth 16. There is. Each helical groove 18 is thus radially juxtaposed to the web 20. In the preferred illustrated embodiment of the invention, each tooth 16 has three radially and circumferentially offset cutting edges: an inner cutting edge 22, an intermediate cutting edge 24, and an outer cutting edge 26. It is formed. Inner cutting edge 22 and intermediate cutting edge 2
4 is formed at the lower end of each web 20, and the web 20
An inner groove 28 and an outer groove m30 for accommodating chips generated by both cutting edges 22 and 24 are formed near the adjacent portions of the groove.

The inner cutting edge 22 is defined by the lower end of the rear surface 27 of the inner groove 28, and the intermediate cutting edge 24 is defined by the lower end of the rear surface 29 of the outer groove 30. On the other hand, the outer cutting edge 26 is defined at the lower end of the rear surface 31 of the spiral groove 18 . The rear surface is generally flat, with the upper ends of grooves 28 and 30 being somewhat rounded.

The inner cutting edge 22 and the intermediate cutting edge 24 have M W132 in the circumferential direction.
The intermediate cutting edge 24 and the outer cutting edge 26 are interconnected at a circumferential shoulder 34.As shown in FIG. Forms a radius that connects with the long continuous cutting edge.

Each of the teeth 16 is formed with a pair of counterfeit surfaces 36.38 extending circumferentially rearward from the cutting edges 22, 24.26, for example in an upwardly inclined direction of about 8° to 10°. As a result, these three cutting edges 22°24.26 are offset in the vertical direction. Historically, the second bevel surface 36 is inclined radially inwardly and upwardly in the ear axis direction, and the second bevel surface 38 is inclined radially inwardly and upwardly in the ear axis direction.
are slanted radially outwardly and axially upwardly. These second verses 36 and 38 are adjacent to each other at the ridge 40. Depending on the purpose of changing the knife, the second bud remover 36 is tilted radially by +25° to -3° relative to the horizontal plane, or tilted approximately 15°, and the second encircler 38 is tilted radially by approximately 15°. It is preferable to tilt it between 5° and 35°, preferably between 5° and 10°.

The valley cutting edges 22, 24, 26 are cut vertically and/or circumferentially for a distance such that the 1.6 cutting edge cuts a single piece of separate chip or at least cuts a thin piece of material which tends to connect the chips. direction. These chips are the cutting edge 22.24
Since it is inclined in the radial and axial directions, it is sent upward through the inner groove 28 and the outer groove 30 and reaches the helical groove 18. Similarly, the chips produced by the outer cutting edge 26 are sent upwardly from the adjacent helical groove 18, so that all the chips are smoothly and easily discharged upwardly through the inclined helical groove 18. .

As shown in FIG. 2, the inner circumference 1m of the wall 14 is radially extended from just behind the intersection line 41 so as to define a gap 42 at 1ul between the inner circumferential surface of the cutter and the rear direction I of the groove 28. There is a counterboring on the outside, which leaves a very narrow margin extending circumferentially rearwardly and upwardly from the inner cutting edge 22 of each tooth. In the embodiment of FIG. 2, the void 42 is
A cylindrical cutter or a grinding wheel 43 is formed by removing three points from the inner peripheral surface of the cutter wall for each tooth, and in that case, a part of the circular arc 44 in the circumferential direction forms a second cut. is defined. It is desirable that the inner circumferential surface of the cutter be cut out by two squares using the appropriate method shown in Fig. 4. In this case, the second cut-out part should not be ground as an arc on the radial inner surface of the ejecting part, but should be cut into a predetermined desired corner section. is ground as a flat surface 46 by a grinding wheel 48 oriented radially through the valley groove 28 . Also, in this case, the width of the gap 50 gradually increases toward the rear.

The maximum width at the margins shall not exceed approximately 1.02 m (0,040 inches) and approximately 0.05 to 0.38 + a (
0,002 to 0,015 inches).

Narrow margins are desirable because they provide radial stability for the blade and prevent over-cutting of the hole. However, it is not essential to provide a margin for each tooth. Inner peripheral surface of cutter and groove 2
When cutting the inner circumferential surface of the cutter directly at the intersection line (shown as a broken line in FIG. 5) with the rear direction 21 of 8, there is a vertically extending lateral cut rather than a vertically extending margin. A blade is formed. This minimizes the friction between the inner circumference of the cutter and the central disk formed by the cutter. However, when manufacturing cutlery based on production standards,
Double cutting all cutting edges on each tool to form vertical cutting edges such that all vertical cutting edges are exactly spaced by the same radial distance from the axis of the tool as a circular grinding margin m. That is difficult. Therefore, it is practical and highly desirable to countershape the blade so as to leave a narrow inner margin on all or at least most of the teeth.

The counterbored portion is formed so that the margin tapers very slightly at the axial tip of the tooth portion and gradually widens upward. This ensures that very narrow margins are created when the knife is first manufactured and after repeated grinding of the knife by sharpening the counterface and groove surface 27. Thus, as shown in FIG.
Grind the top width to approximately 0.38 m (0.015 inch). Preferably, the perpendicularity of the margin is slightly greater than the perpendicularity of the groove 28 so that the counterbore 42,50 extends upwardly at least slightly beyond the upper end of the groove 28.

As pointed out in the preamble, when using the general type of annular cutter mentioned above, problems can arise when chips get stuck between the inner circumferential surface of the side wall of the cutter and the outer circumferential surface of the central disk formed by the cutter. be. This problem is substantially eliminated by providing a very narrow margin on the inside of each +fl space combined with a gap path. That is, even if chips enter between the inner circumferential surface of the cutter and the central disk, the chips will be broken or at least sufficiently abraded due to the narrow margin or the high unit pressure generated by the vertical side cutting edges. , into the void or passage, and then radially outward to the next continuous groove and spiral groove.

From the foregoing, the radial dimensions of the relief passage 42.50 must be sufficient to accommodate any chips that enter the cavity. That is, about 0.13 + structure (tl,
005 inch) in which the cutter is operated at a feed rate that results in a chip load (chip thickness) at the neck. Accordingly, the escape passage has a radial dimension such that it connects with at least the next column of said dimension. However, it is necessary to minimize the radial dimension of the escape channel at a position close to the trailing edge of the margin, as described above, so that the escape channel and the margin can freely escape to the facing straight edge. Experiments have shown that at least about 3°, preferably at least 7
If the relief channel is defined by a surface that slopes radially outward at an angle of
3++ on (0,005 inches) to allow sufficient access to the margin or side cutting edge to facilitate the evacuation of chips passing therethrough. The angle with respect to the tangent line is shown as soil in Figures 2 and 4, and is approximately 12°.
This is suitable for a cutter having the shape shown in FIG. If the void is formed as an arcuate channel having a maximum width between the ends, the width of the outlet end of the channel should be at least about 0.13 m (0.13 m).
005 inches).

If the cutter is supplied with coolant directed downwardly through the central passage 54 of the cutter shank, the void will naturally have an additional function.

That is, since the tooth portion is directly cooled with a large amount of coolant, *U of the tooth portion is smaller than when no gap is provided.

From the perspective of effectively cooling the teeth, it is desirable that the volume of the void be as large as possible, but it is important not to reduce the quality of each tooth to the extent that it weakens the strength inherent to each tooth. You have to go back and take a second cut of the tooth.

In order to clarify the results obtained with the cutlery formed according to the present invention, the results of experiments conducted on two types of cutlery under the same conditions are shown below. The outer diameter of both blades is 25.
4-22.2 m (1-L inch) and has the overall shape shown in FIG. The purchase and dimensions of both cutlery are the same, the cutter shown below as "mu" has no till margin, while the cutter shown as "kI" is cut in the same way as shown in Figure 4. Form the inner margin and set the width of the closing margin to approximately 0.05~0.13mm (0,002~o,
o o s inches). Both knives 2"1018
15OR,P,M to form a hole through the steel bar of
I rotated it.

The advantages of the present invention can be easily understood from the above results.

In all cases, the increase in the hole formed with knife B was actually small and the finish was smooth. The faster the feeding speed of cutter B was increased, the smaller the horsepower and thrust required. Since it is thought that applying a cutting load of 0.13 rra (0,005 inch) to the blade ram would cause it to break, an experiment in which a load of 0.13 m (0,005 inch) was applied to the blade ram was not conducted.

[Brief explanation of the drawing]

Figure 1 is a side view of the dovetail cutter according to the present invention, Figure 2 is a plan view of the main part showing its lower end, and Figure 3 is a cross section taken along line 3-3 in Figure 1.
4 is a plan view similar to FIG. 2 showing another embodiment of the annular cutter according to the present invention, and FIG. It is a partial elevation view. 10・・・・・・・・・・・・・・・・・・Annular cutter 14・・・・・・・・・・・・・・・・・・・・・
Side wall 16・・・・・・・・・・・・・・・・・・
・Tooth part 18・・・・・・・・・・・・・・・・・・
...Spiral groove 22.24.26...Cutting blade 6-28.30...Groove 21...
・・・・・・・・・・・・・・・Rear surface 29 of groove 28・
・・・・・・・・・・・・・・・・・・Rear surface of groove 30 42.50・・・・・・Gap m...
・・・・・・・・・・・・・・・・・・・Margin 43.48・・・・・・・・・Grinding wheel 46・・
・・・・・・・・・・・・・・・・・・Escape route 54
・・・・・・・・・・・・・・・・・・ Coolant passage patent applicant Everett Douglas Haugen procedural amendment (voluntary) June 20, 1980 Manabu Shiga, Commissioner of the Patent Office 1. Indication of the case Patent Application No. 071897 of 1982 2. Title of the invention i. Relationship to the case by the person making the amendment Patent applicant address 1184 Normandy Terrace, Flint, Michigan 48504, United States of America Name Everett Douglas Haugen 4, Agent Person 5, Date of amendment order: Showa Year, Month, Day 6, Number of inventions increased by amendment 5

Claims (1)

[Scope of Claims] (1) The main body is provided with a substantially cylindrical side wall, and a plurality of teeth are formed around the lower end of this side wall at intervals in the circumferential direction, while around the outer peripheral surface of the side wall, A plurality of spiral grooves are formed extending upward from between the adjacent teeth, each of the teeth is provided with at least one cutting edge extending in the radial direction, and chips cut by the cutting edge are removed. Grooves extending radially outward from the inner circumferential surface of the side wall to the helical groove are provided for discharge radially outwardly and upwardly into the helical groove; by providing a radial rear surface extending upwardly from the inner portion in the radial direction, and by recessing the inner circumferential surface of each tooth portion outward in the radial direction, the inner circumferential direction of the tooth portion and the annular cutter A radial gap extending in the circumferential direction is defined between the central disk portion that is being formed in the workpiece, and the gap is approximately 1.02 tm from the line where the inner circumferential surface and the rear surface of the groove intersect. (
an annular cutter wherein the gap extends rearwardly from a generally vertically extending line spaced rearwardly by a distance of 0.040 inches). (2) The annular cutter according to claim 1, wherein the gap forms a relief path extending radially rearward from the inner peripheral direction of each tooth portion to the next adjacent groove. (3) The radial gap is at least about 0.13 t++++++ (0,005 inches) from the line by an angle of at least about 3° to 7° to the tangent to the inner circumference in the vertical extension line. Claim 2, wherein the void is defined by a generally vertical plane that slopes radially outwardly to such a point that the gap is thereafter greater than or equal to about 0.13 m+ (0,005 inch). Annular cutlery as described in section. (4) in at least some of the teeth,
4. An annular cutter according to claim 3, wherein said vertically extending line is spaced rearwardly from said line of intersection to define a margin of width of at least 0.05 ms+ (0,002 inches). (5) In at least some of the teeth, the vertical extension line is spaced rearwardly from the intersection line by at least about 0.005 to 0.38 mm (0.002 to 0.0 mm).
4. The annular cutter according to claim 3, wherein the annular cutter forms a margin having a circumferential width of 15 inches. (6) The current cutter according to claim 3, wherein the core portion is a flat surface as a whole so that the q-module in the radial direction of the escape path gradually increases in the radial direction. . 5. The annular cutter according to claim 4, wherein the vertical extension line is slightly inclined rearward with respect to the intersection line so that the two wheels of the margin are wider than the lower end. (8) The annular cutter according to Patent β)-B No. 48i, wherein the margin is at least in the same space as the intersection line in terms of height. (9) Each tooth section is provided with a plurality of cutting edges offset in the circumferential direction, so that the inner cutting edge in the radial direction is forward from the next radially adjacent cutting edge in the rotational direction of the blade. The annular cutter according to claim 3, wherein the annular cutter is located at . OI An annular cutter according to claim 9, wherein the vertical surface is flat and inclined radially outward at an angle of about 12 degrees with respect to the tangent. αυ Claim 3, characterized in that the body has axially pure passages for the passage of coolant.
An annular knife described in JJ.