TW200406274A - O-shaped blade - Google Patents

Abstract

The present invention is to provide an O-shaped blade which, at the same time, has exhaust efficiency of waste caused by machining, and has excellent durable property. The present invention is to provide an O-shaped blade which is characterized in that in a circumferential direction of the O-shaped blade bottom having cylinder-shaped body, there are a first cutting knife and a second cutting knife which are staggered; the blade of the first cutting knife is a tilting surface which is formed by the fact that a central portion of width direction of cutting blade is outer than a tip which is at upper ends of two ends of the width direction; on the tilting surface of inner tilting of the second cutting blade, through steps, a plurality of tilting surfaces are formed in a non-continuous manner. In front view, below the step which is formed on the tiling surface of the blade of the second cutting knife, the blades of the first cutting knife and the second cutting knife and the tilting surface of the blades of the blade inner ends of the first cutting blade are installed in a staggered manner. In front view, below the tiling surface of the outer ends of blade of the first cutting knife, the tilting surface from the tip toward the outer end is overlapped, so as to form a cutting tilting surface.

Description

200406274 (1) [Explanation of the invention] 1. [Technical field to which the invention belongs] The present invention relates to a ring-shaped cutting tool for forming a round hole through cutting a work by cutting it into a ring, and in particular, it can improve the cause of the problem. A circular cutter with excellent durability and discharge efficiency of cutting chips. 2. [Prior art] Conventionally, as a ring cutter for forming a through-hole in a work, there is a ring cutter and the like proposed in Japanese Patent Application Laid-Open No. 9-201710. The structure of the annular cutter described in the aforementioned publication will be described with reference to the drawings. Fig. 9 is a side view of the annular cutter, and Fig. 10 is a bottom view of the annular cutter. Figs. 1 (a), (b), (C) The figure is a front view of a 1st cutting edge and a 2nd cutting edge, and a front view which overlaps a 1st cutting edge and a 2nd cutting edge, respectively. At the front end (bottom) of the tool body 12 formed in a cylindrical shape, as shown in FIGS. 9 and 10, a plurality of first cutting edges 1 3 are alternately mounted and fixed to the circumferential direction of the tool body 12 at predetermined intervals. 5 with 2nd cutting edge. When viewed from the front, the first cutting edge and the second cutting edge are formed as shown in Figs. 11 (a) and (b), and the widthwise ends 15a and 15b of the second cutting edge 15 are formed. The height of the blade edge is set to be slightly smaller than the height of the blade edge at both ends 13a and 13b in the width direction of the first cutting edge 13 as shown in Fig. 11 (c). In addition, the second cutting edge is further set. The height of the blade edge of the center portion 15c in the width direction on 15 is set to be larger than the height of the blade edge of the center portion 13c in the width direction on the first cutting edge 13. Then, it is provided at the central portion in the width direction of the blade edge 16 at the front end of the second cutting edge 15 to form a flat portion 17 extending linearly. In the ring cutter 11, by forming the above-mentioned 200406274 blade shape, it is possible to easily discharge the cutting chips generated when the first cutting edge 13 and the second cutting edge 15 are cut out of the groove while cutting the work W, It is also possible to divide the cutting chips generated when the first cutting edge cuts the workpiece W into two, and it is possible to make the blade edge provided on the cutting edge difficult to break. In the figure, 0 is the holding angle, PI and P2 are the apex, 14 is the blade edge, 18 is the chip discharge groove, and 19 is the inclined guide surface. 3. [Contents of the Invention] [Problems to be Solved by the Invention] However, in the aforementioned ring-shaped tool 11, the shape of the blade 16 provided at the front end of the second cutting edge 15 is as shown in FIG. 11 (b). As shown in the figure, the shape of the flat portion 17 extending linearly is provided at the central portion in the width direction. Therefore, there is a problem that cutting chips generated by the first cutting edge cannot be divided into two. In addition, the blade has a large frictional force when cutting the groove, and there are cases where the blade is damaged due to the frictional force. Therefore, in order to solve the aforementioned problem, the present inventor has proposed a ring-shaped tool capable of cutting and cutting a chip into two or more sections by cutting the shape of a blade edge provided on the ring-shaped tool (Japanese Patent Application Laid-Open No. 2002-1 03 1 25) . This ring cutter is as shown in Fig. 12 (a), (b), (c), and is characterized in that the circular cutter with a cylindrical body is arranged alternately at predetermined intervals in the circumferential direction of the bottom of the ring cutter. The first cutting edge 41, the second cutting edge 45, and the first cutting edge 44 are inclined surfaces formed by vertices P1 which are arranged at a more peripheral end than the central portion in the width direction of the cutting edge toward the upper ends of both ends in the width direction. 44a, 44b, the cutting edge 46 of the second cutting edge 45 is an inclined surface 46a, 46b, 46c formed by a vertex P2 arranged at a more peripheral end than the vertex of the first cutting edge toward the upper ends of the widthwise ends. In addition, the inclined surfaces 46b and 46c inclined from the top 200406274 points to the inner peripheral end are formed discontinuously through the step portion 47. The inclined surfaces 46b and 46c of the cutting edge of the second cutting edge 45 are viewed from the front. Below the formed step portion 47, the cutting edges of the first cutting edge 41 and the second cutting edge 45 are arranged alternately with the inclined surface 44b at the inner peripheral end of the cutting edge of the first cutting edge 41, and can be improved by this configuration. Exhaust efficiency of cutting chips generated by cutting. However, in the circular cutter described in this publication, the inclined surfaces 44a and 46a formed on the peripheral ends of the first and second cutting edges are not overlapped when viewed from the front (see FIG. 12 (c)), When the cutting object opens the through hole, the peripheral end of the through hole is cut only by the inclined surface 46a of the peripheral end of the second cutting edge 45, and the inclined surface 44a of the peripheral end of the first cutting edge 41 is idle. . In such a circular cutter, if the material of the workpiece to be cut is a material with a general degree of hardness, there is no problem. However, for example, in the case of high-hardness materials that have been calcined, such as the track used for the Shinkansen, in The inclined surfaces 44a, 46a of the outer edges of the aforementioned first and second cutting edges are not overlapping on a circular tool when viewed from the front. The peripheral inclined surface 46a of the second cutting edge 45 of the cutting periphery has a considerable load. The abrasion of the peripheral end inclined surface 46a of the second cutting edge 45 progresses, and there is a problem in durability of the annular cutter. There is also a problem in that the hardness (cutting point) of the angle 48 of the inclined surface of the peripheral end of the second cutting edge 45 is generated due to the high hardness of the cutting object. In particular, the cutting edge of the outermost portion of the cutting through hole in the ring-shaped tool is subjected to a large load due to the high rotation speed of the cutting edge. In addition, the peripheral portion is cut only by the peripheral end inclined surface 46a of the second cutting edge 45. The cutting efficiency is also not good, and because of the poor cutting degree, the blade stickiness occurs during cutting, resulting in the situation that the ring tool cannot rotate smoothly. 200406274 Therefore, in the present invention, it is provided that the inclined surface of the peripheral end is formed from the vertices of the first and second cutting edges under the front view to form an inclined surface that overlaps each other. When the through hole is opened, the first 2. The inclined surface of the second cutting edge overlaps (that is, the individual peripheral end inclined surface) is the peripheral end of the cutting through hole, so as to reduce a large load on the peripheral end inclined surface of the second cutting edge applied to the cutting periphery. To improve the cutting efficiency and improve the durability of the ring cutter, the purpose is to solve the aforementioned problems. It also aims at reducing the wobble of the ring cutter and improving the dimensional accuracy of the opening of the workpiece by means of cutting resistance of the outer edge > cutting resistance of the inner edge. III. [Content of the Invention] In order to achieve the foregoing object, the technical solution adopted by the present invention is a ring cutter, which is characterized by alternately disposing the first and second cutters at a predetermined interval in the circumferential direction of the bottom of the ring cutter having a cylindrical body. 1 cutting edge, 2nd cutting edge; the cutting edge of the 1st cutting edge is an inclined surface formed by vertices located at the outer edge of the cutting edge in the widthwise center portion toward the upper ends of both ends in the width direction; The blade edge is an inclined surface formed by vertices located on the outer edge of the first cutting edge toward the upper ends of both ends in the width direction; on the inclined surface inclined from the vertex of the second cutting edge to the inner end, The stepped portion is formed discontinuously with a plurality of inclined surfaces. Under the stepped portion formed on the inclined surface of the cutting edge of the second cutting edge in front view, the cutting edge of the first cutting edge and the second cutting edge are related to the first cutting. The inclined surfaces of the inner peripheral end of the cutting edge of the blade are arranged alternately; under the oblique surface of the peripheral end of the cutting edge of the first cutting edge when viewed from the front, from the vertex to the periphery The inclined surface at the end is an overlapping tangent surface. The present invention is also a ring-shaped cutter, which is characterized in that it has a cylindrical shape.

The first cutting edge and the second cutting edge are alternately arranged at a predetermined interval in the circumferential direction of the bottom of the ring-shaped cutter of the body; the edge of the first cutting edge is arranged at a vertex that is more peripheral than the center of the width direction of the cutting edge. The inclined surfaces formed at the upper ends of both ends in the width direction are formed at least on the inclined surface that holds the inside of the apex, and a plurality of inclined surfaces are formed discontinuously due to the stepped portion; the blade edge of the second cutting edge is arranged at A plurality of inclined surfaces formed by vertexes that are more outward than the vertices of the first cutting edge toward the upper ends of both ends in the width direction are formed at least on the inclined surface that holds the inside of the vertices. Inclined surface; under the difference between the front edge formed on the first cutting edge and the second cutting edge, the first cutting edge and the second cutting edge are connected to each other to the edge of the cutting edge formed on the other side The inclined surfaces are arranged in a staggered manner; under the oblique surface of the peripheral end of the blade edge of the first cutting edge in front view, it is inclined from the vertex to the peripheral end The inclined surface of the cut lines formed by overlapping ramp.

Further, the annular cutter according to the present invention is characterized in that it is formed on an inclined surface that is more inward than the apex of the first cutting edge and the second cutting edge, and is formed in parallel with each other. The ring cutter according to the present invention is characterized in that when the first cutting edge is used as the outer edge and the second cutting edge is used as the inner edge, the cutting resistance of the workpiece generated by the outer edge and the workpiece generated by the inner edge Cutting resistance is a condition that satisfies the cutting resistance of the workpiece generated by the outer edge > the cutting resistance of the workpiece generated by the inner edge. The ring cutter according to the present invention is characterized in that the first cutting edge is an outer edge, the second cutting edge is an inner edge, and the edge shape of the outer edge and the inner edge (retraction angle, rake angle) On the same occasion, the cutting resistance of the outer edge produced by the -10- 200406274 workpiece and the cutting resistance of the inner edge produced by the outer edge satisfy the cutting resistance of the outer edge produced by the workpiece > (cutting by the outer edge of the workpiece) Resistance + cutting resistance of the workpiece generated by the inner edge) / 2. Fourth, [Embodiment] The first embodiment of the present invention will be described below with reference to Figs. 1 to 4 (b). Fig. 1 is a side view of the ring cutter according to the embodiment of the present invention. Fig. 2 is a bottom view of the annular cutter according to the embodiment of the present invention, Fig. 3 (a) is a front view of the first cutting edge, Fig. 3 (b) is a front view of the second cutting edge, and 3 ( c) The drawing is a front view in a state where the first cutting edge and the second cutting edge are overlapped, and the fourth (a) drawing is a schematic diagram of the cutting state of the work produced by the second cutting edge. The fourth drawing (b) Schematic diagram of the cutting state of the workpiece produced by the first cutting edge. In the following description, the bottom of the ring-shaped cutter refers to the vertex end of the ring-shaped cutter carving wind. As shown in Fig. 1, the cutter body 2 of the ring cutter 1 is formed in a cylindrical shape, and the ring cutter 1 is mounted on a portable punching machine (not shown) through a one-touch joint or a fixing mechanism such as a screw. Or a work machine that rotates in the direction of arrow A. As shown in FIG. 1 and FIG. 2 'on the lower end surface of the tool body 2, a plurality of first cutting edges 3 and a second cutting edge 5 composed of a super-hardened tip are alternately arranged on the tool at a predetermined interval. The main body 2 is welded in the circumferential direction. In addition, as shown in FIG. 1, a cutting chip discharge groove 8 inclined downward in the direction of the arrow A is formed on the peripheral surface of the tool body 2, and each cutting is formed in the circumferential direction of the tool body 2 at predetermined intervals. The lower end portion of the chip discharge groove 8 is disposed between each of the cutting edges 3 and 5. As shown in Fig. 3 (a), at the front end of the first cutting edge 3, a first blade edge 4,200,406,274 arranged in the width direction of the blade edge is provided. In addition, the first blade edge is viewed from the front (the direction of rotation of the tool). The tangent direction) is slightly V-shaped, and forms a first inclined surface 4a and a second inclined surface 4b facing upward in the width direction of the holding vertex P1. The apex of the first blade edge 4 is formed closer to the peripheral end of the tool body 2 than the center in the width direction of the blade edge 4 (see Fig. 2).

At the front end of the second cutting edge 5, a second blade 6 arranged in the width direction of the blade as shown in Fig. 3 (a) is provided, and the second blade 6 is formed to protrude toward the W end of the workpiece. The second blade edge 6 is located closer to the peripheral end of the tool body 2 (refer to FIG. 2) than the center of the width direction of the blade edge 6 (see FIG. 2). The peripheral edge from the vertex P2 forms the first edge of the first cutting edge 3. The first inclined surface 6a is overlapped with the inclined surface 4a, and the inner peripheral end from the vertex P2 is formed to be slightly parallel to the second inclined surface 4b of the first cutting edge 3 and discontinuous due to the step 7 The second inclined surface 6b and the third inclined surface 6c. Then, as shown in FIG. 3 (b), the second inclined surface 6b and the third inclined surface 6c are formed as a whole below the third inclined surface 6c as a whole. Next, as shown in FIG. 3 (c), the first cutting edge 3 and the second cutting edge 5 are in the first cutting edge 3 when the first cutting edge 3 and the second cutting edge 5 are superimposed and viewed from the front. The first inclined surface 4a at the outer peripheral end in the width direction and the first inclined surface 6a at the outer peripheral end in the width direction in the second cutting edge 5 are formed so as to overlap each other when viewed from the front, and the third inclined surface 6c presents It protrudes below the second inclined surface 4b of the first cutting edge 3, and the vertex P2 of the second cutting edge 5 is higher than the vertex P1 of the first cutting edge 3, and the first cutting -12-200406274 of the cutting edge 3 The second inclined surface 4b is located above the third inclined surface 6c in the widthwise peripheral end of the second cutting edge 5 and below the second inclined surface, so that the vertex P 1 becomes the most Protruded like a lower end. Therefore, the step 7 formed on the cutting edge 6 of the second cutting edge 5 is formed so as to intersect the second cutting slope 4b of the cutting edge 4 formed on the first cutting edge 3.

In addition, on both sides of the first and second cutting edges 3 and 5, in order to prevent sticking of the cutting edges, both sides of the cutting edges 3 and 5 are formed into a tapered shape that narrows upwards, and the cutting edges are cut during cutting. 3 and 5 will be shaped to prevent sticking to the work. It should be noted that both sides of the cutting edges 3 and 5 are not limited to a tapered surface and are parallel to each other as in the conventional example.

Next, the operation of the ring cutter 1 configured as described above will be described. When the work W forms a through hole, the ring cutter mounted on the portable puncher or the work machine is rotated around the periphery as the center of the arrow A, and the first and second cutting edges 3, 5 is close to the workpiece W, and the ring cutter 1 is moved in the axial direction by a predetermined amount of movement. Then, when the first and second cutting edges 4 and 6 of each cutting edge 3 and 5 are in contact with the workpiece W, the workpiece W is cut by each of the cutting edges 4 and 6 and the workpiece W is at each of the cutting edges 3 and 5 A groove 10 is formed on the rotating track as shown in FIGS. 4 (a) and (b). As shown in FIG. 4 (a), the peripheral end of the bottom surface of the groove 10 is cut by the first inclined surface 4a formed on the first cutting edge 4 and the first inclined surface 6a of the second cutting edge 5, In addition, the inner peripheral end 1 of the bottom surface of the groove 10 has a shape corresponding to a side end portion inside the second blade edge 6. In other words, the first cutting edge 3 cuts the central portion of the groove 10 in the width direction and the end of the outer periphery as shown by diagonal lines in FIG. 4U) to generate cutting chips -13- 200406274 22. The second cutting edge 5 cuts both ends of the groove 10 as shown by diagonal lines in Fig. 4 (b) to generate cutting chips 2 1 a and 2 1 b. The bottom surface of the groove 10 is cut by the aforementioned first and second cutting edges 3 and 5. The peripheral end of the bottom surface of the groove 10 is inclined by the first of the first and second cutting edges 3 and 5. The surfaces 4a, 6a are cut, and both ends of the bottom surface width direction and the central portion are divided into three and cut. Therefore, the peripheral end of the groove 10 is cut by the first and second cutting edges 3 and 5 at any time, which can reduce abrasion and damage of the first and second cutting edges 3 and 5 compared with the conventional ring cutter. . The chips 21a, 21b, and 22 cut from the bottom surface of the groove 10 are guided by the chip discharge groove 8 shown in FIG. 1 to be discharged outside the groove 10. After that, the grooves formed by the ring-shaped cutter 1 are continuously formed, and when the ring-shaped cutter 1 penetrates the work W, a through-hole is formed in the work W. Next, a second embodiment of the present invention will be described. The second embodiment is an example of cutting chips more than the first embodiment. In this example, the chip can be divided into four. The second embodiment is provided with a first cutting edge 31 and a second cutting edge 32 having a shape as shown in FIGS. 5 (a) and (b), and a plurality of first cutting edges 31 and a second cutting edge 32 are alternately arranged. Welded on the circumference of the bottom surface of the tool. On the blade edge 40 of the first cutting edge 31, the vertex P1 is disposed at a more peripheral end than the center portion in the width direction of the blade edge 4. Therefore, the inner peripheral end from the vertex P1 is formed with the first end described in the first embodiment. 2 The cutting edge 5 is the same as the discontinuous third inclined surface 31 c due to the step portion 3 3, and the second cutting inclined surface 31 b forms the continuous first inclined surface 3 1 from the apex P1 of the blade edge 40. a. Also, the blade edge 60 of the second cutting edge 32 is the same as the first cutting edge 31, and the vertex P2 is disposed at a peripheral edge of -14-200406274 from the vertex P1 of the first cutting edge 31, and thus the vertex P2 The inner peripheral end is formed with a third inclined surface 3 2 c which becomes discontinuous due to the step difference 34, and the second cut inclined surface 3 2 b. The peripheral end from the vertex P1 of the blade edge 60 0 forms a continuous first. Inclined surface 32a. Next, the first inclined surfaces 31a and 32a of the peripheral ends of the first cutting edge 31 and the second cutting edge 32 are formed as inclined surfaces overlapping each other when viewed from the front, and are formed on the first cutting edges 31 and 2 respectively. The positions of the stepped portions 33 and 34 of the cutting blade 32 are set at non-overlapping positions as shown in Fig. 5 (c) when viewed from the front, and the stepped portion 33 and the second inclined surface 32c are respectively different from the stepped portion. The portion 34 intersects the second inclined surface 3 1 b. With the aforementioned configuration, the peripheral end portion of the groove 10 is cut at any time by the first inclined surface 3 1 a and the second inclined surface 32 a of the second cutting edge, and the width of the cutting chips is narrowed by cutting. Four out. In other words, the first cutting edge 31 in the bottom surface of the groove 10 will cut 3, 6, 7, 3, and 8 in the width direction of the bottom surface of the groove 10, and the second cutting edge 3 2 will cut 35 and 36 shown in the diagonal direction of Fig. 5 (c) in the width direction of the bottom surface of the groove 10 to generate cutting chips. Also, the cutting chips cut by the groove 10 are guided through the chip discharge groove 8 shown in FIG. 1 to be discharged outside the groove 10. Thereafter, the formation of the grooves generated by the ring-shaped tool 1 is continued, and when the ring-shaped tool 丨 penetrates the work W, a through-hole is formed in the work W. In the embodiment shown in Figs. 5 (a), (b), and (c), the blade edges at the peripheral ends from the vertices pi and p2 are formed with one inclined surface 3 1 a, 32 a, but they are inclined here. The surface can also form an inclined surface with a stepped portion at the inner periphery end from the vertices P 丨 and P2. The number of 'segment difference' may be two or more. Next, a third embodiment according to the present invention will be described. The third embodiment -15-200406274 is an example for improving the accuracy of the hole to be penetrated. The cutting edges of the ring cutter 1 of the first and second embodiments described above are the cutting edges 3 a of the first cutting edge (outer edge) 3 as shown in FIG. 6, and are formed at the peripheral end edge 3 b and the inner peripheral end edge. Between 3c, the blade edge 5a of the second cutting edge (inner edge) 5 is formed between the peripheral end edge 5b and the inner end edge 5c. Then, the peripheral end edges 3b and 5b of the first cutting edge 3 and the second cutting edge 5 are arranged on a circumference centered on the center of the output shaft 0 of the motor, and the inner end edges 3c and 5c are disposed on the circumference. The output shaft center 0 and the eccentric center axis (0 ') are arranged on the circumference of the center. Therefore, when the workpiece W is drilled by the annular cutter 1, the annular groove is cut on the workpiece W by the first cutting edge 3 and the second cutting edge 5 through the feed of the annular cutter, and finally, After the hole is completed, the cutting condition of the workpiece W is as shown in FIG. 7, and the groove is cut through the blade edge 3a of the first cutting edge (outer edge) 3 and the blade edge 5a of the second cutting edge (inner edge) 5. L) The common cutting range S 3 at the peripheral end is used for cutting, and the cutting range S 1 at the middle part of the groove is continuously cut through the cutting edge 3a of the first cutting edge (outer edge) 3, and the second cutting is performed through the second cutting. The cutting edge 5a of the cutting edge (outer cutting edge) 5 continuously cuts the cutting range S2 of the middle portion of the groove to form a through hole. At this time, the edge 3c of the cutting edge 3a inside the first cutting edge 3 of the ring cutter 1 and the edge 5c of the cutting edge 5a inside the second cutting edge 5 are arranged eccentrically with respect to the center 0 of the output shaft. On the other hand, the cutting is performed around the center of the output shaft 0 as a result of rotation. As a result, it remains inside the through hole formed on the work W by the edge 5 c and the edge 3 c. A gap is generated between the periphery of the removed portion of the workpiece W, which can avoid the situation where the removed portion can bite the inner diameter portion of the ring cutter 1 and cannot be removed from -16-200406274. However, when the cutting edges 3a, 5a of the inner peripheral ends of the first and second cutting edges 3, 5 which are eccentrically set to the center of rotation of the ring-shaped tool 1 are cut as described above, it may occur The following questions. Specifically, as shown in FIG. 7, when the workpiece W is cut by the ring cutter 1, the cutting is performed in addition to the common cutting range S 3 of the workpiece W through the two blade edges 3 a and 5 a. The ranges are not the same as shown. In other words, the cutting range S1 of the workpiece W is cut by the cutting edge 3a of the first cutting edge (outer edge) 3 and the cutting range S2 of the workpiece W is cut by the cutting edge 5a of the second cutting edge (inner edge) 5. The cutting ranges shown in Figure 7 are not the same. Therefore, the cutting resistance applied to the outer edge 3 during cutting is determined by (common cutting range S3 + outer cutting range S1), and the cutting resistance applied to the inner edge 5 during cutting is (common cutting range S3 + within) The cutting range S2) is determined. For example, when the cutting resistance when cutting the workpiece W with the inner edge 5 is greater than the cutting resistance when cutting the workpiece W with the outer edge 3, the ring cutter 1 is determined by the inner blade 5 and the cutting edge 3 of the outer blade 3. a will rotate eccentrically. When the cutting resistance when cutting the workpiece W with the inner blade 5 is smaller than when the cutting resistance is cut with the outer blade 3 when the workpiece W is cut, the 'ring tool 1' is determined by the outer blade 3, and the inner peripheral end of the ring tool The blades 3a, 5a will rotate eccentrically. As a result, for example, when (common cutting range S3 + outer cutting range S1) > (common cutting range S3 + outer cutting range S2), the cutting resistance during cutting generated by the outer cutting edge 3 increases. The dimensional accuracy of the through hole is determined by the outer edge 3. The dimensional accuracy will become better. -17- 200406274 However, in the case of (common cutting range S 3 + outer cutting range s 1) < (common cutting range S 3 + outer cutting range S2), the cutting resistance during cutting generated by the inner edge 5 will be As a result, the ring cutter 1 will be affected by the cutting range S 2 of the inner edge. Since it rotates around the center axis 0 after eccentricity, the blade edges 3 a and 5 a at the outer end will sway ( Eccentricity), the dimensional accuracy of the through hole will be worse. In other words, when the blade edges 3a, 5a at the inner peripheral ends of the outer edge 3 and the inner edge 5 rotate around the output shaft center 0, the outer size of the removed portion (chips) of the work W can be reduced. The size of the through-hole for perforation of the workpiece w can be processed with good accuracy. When the blade edges 3 a and 5 a of the inner edge of the outer edge 3 and the inner edge 5 rotate around the eccentric rear central axis 0 ′, It will greatly affect the size of the through-holes through which the work W is perforated, and the accuracy of the size of the through-holes will be significantly reduced. Therefore, in the third embodiment, in order to prevent the accuracy of the size of the through hole from being reduced during the aforementioned perforation, it is possible to eliminate the wobble (eccentricity) of the blade edges 3a and 5a of the inner peripheral end of the outer edge 3 and the inner edge 5 and increase the size of the through hole. With accuracy, the cutting resistance during cutting of the outer edge 3 and the inner edge 5 will form the characteristics of the blade edges 3a and 5a as described below. Fig. 8 (a) is a front view of the cutting state of the workpiece W produced by the first and second cutting edges 3 and 5 of the ring-shaped tool described in the third embodiment, and the cutting edges of the outer edge 3 and the inner edge 5 The shapes (recess angle, rake angle) of 3a and 5a are the same, and they are generally determined (common cutting range S3 + outer cutting range S1) > (common cutting range S3 + outer cutting range S2) Examples of the shapes of the blade edges 3a, 5a. Therefore, the rotation of the ring cutter 1 is because the cutting resistance during the cutting of the outer edge 3 becomes larger than the cutting resistance during the cutting of the inner edge 5-18-200406274. Therefore, the accuracy of the size of the through hole becomes better. In addition, when the shapes of the cutting edges 3a and 5a (retraction angle, rake angle) of the outer edge 3 and the inner edge 5 are different, the entire cutting range is not formed, and the outer edge 3 and the inner edge 5 The magnitude of the cutting resistance determines the rotation of the ring cutter 1. FIG. 8 (b) is a front view of the cutting state of the workpiece W produced by the first and second cutting edges 3 and 5 of the ring-shaped tool according to the third embodiment, and the cutting edge 3a of the outer edge 3 and the inner edge 5 The shape of 5 and 5a (retraction angle, rake angle) are the same, except for the common cutting range S3 (removing the part where the outer edge 3 and the inner edge 5 overlap in front view), and the outer edge cutting range S 1 > For the example of the outer edge cutting range S2, the rotation state of the ring cutter 1 in the aforementioned FIG. 8 (a) is determined by the cutting resistance during the cutting of the outer edge 3 and the cutting resistance during the cutting of the inner edge 5. Can improve the dimensional accuracy of the through hole. As described above, in the third embodiment, when cutting through the outer edge and the inner edge, the cutting resistance between the outer edge and the inner edge must satisfy the relationship between the outer edge cutting resistance and the inner edge cutting resistance. The outer edge and the inner edge are formed in a manner that satisfies the aforementioned conditions, which can improve the dimensional accuracy of the through hole. Also, in the case where the shapes of the cutting edges of the outer edge 3 and the inner edge 5 (retraction angle, rake angle) are the same, the outer edge cutting range S 1 > (the outer edge cutting range S1 + the inner edge cutting range S2) / 2, the relationship between the cutting resistance of the outer edge & the cutting resistance of the inner edge is established. In the embodiment described above, the peripheral end of the groove is cut by the first cutting edge and the second cutting edge at any time, so it is possible to prevent the periphery of the first and second cutting edges having the greatest cutting resistance during cutting. Wear and damage of parts. In addition, a discontinuous inclined surface due to a stepped portion is formed at the cutting edge of the first cutting edge and the second cutting edge, and the discontinuous portion is arranged at a position that does not overlap each other when viewed from the positive -19-200406274 plane. , Can be divided into detailed cutting chips. In addition, by increasing the number of steps or forming inclined planes that hold the apex points, respectively, there is a method of discontinuous inclined planes formed by step sections, which can further divide the chip into finer details. In addition, since a discontinuous inclined surface is formed at the blade edge via a stepped portion, the processing of the blade edge is relatively easy. Although the above is an explanation of the embodiments of the present invention, the foregoing embodiments are merely examples. The present invention may be implemented in various other forms without departing from the spirit and main characteristics of the present invention, and is not limited thereto. . [Effects of the Invention] As described in detail above, it can be achieved in the present invention that the cutting bevels which are more peripheral than the vertices P 1 and P 2 of the first cutting edge and the second cutting edge are overlapping inclined surfaces when viewed from the front. Therefore, it is possible to prevent abrasion and breakage of peripheral portions of the first and second cutting edges during cutting. In addition, at the cutting edge of at least one of the cutting edges formed by the first cutting edge and the second cutting edge, an inclined surface discontinuous due to a stepped portion is formed, and the stepped portion is formed in front of the first cutting edge in a front view. The inclined surface at the blade edge is arranged in such a way that the cutting chips can be divided in detail. In addition, because the blade edge is provided with a discontinuous inclined surface formed by a stepped portion, the processing of the blade edge is relatively easy. Since the strip-shaped chips cut by the blade edge are located away from the width direction, the chips can be prevented from each other. The entanglement makes it possible to easily discharge the cutting chips generated when cutting the work to the outside of the groove. In addition, the outer edge cutting resistance > the inner edge cutting resistance can improve the dimensional accuracy of the opening of the workpiece, and the like. -20- 200406274 V. [Simplified description of the drawing] Figure 1 is a side view of the annular cutter according to the embodiment of the present invention. Figure 2 is a bottom view of the annular cutter according to the embodiment of the present invention. (a) is a front view of the first cutting edge, FIG. 3 (b) is a front view of the first cutting edge, and FIG. 3 (c) is a front view of the state where the first cutting edge is overlapped with the first cutting edge . Fig. 4 (a) is a schematic diagram of the cutting state of the working object generated by the second cutting edge, and Fig. 4 (b) is a schematic diagram of the cutting state of the working object generated by the second cutting edge. Fig. 5 (a) is a front view of the first cutting edge of the ring cutter described in the second embodiment, Fig. 5 (b) is a front view of the second cutting edge, and Fig. 1 is the first cutting edge and the first cutting edge. 2 The front view of the state of the work produced by the cutting blade. Fig. 6 is a bottom view of the ring cutter according to the first embodiment. Fig. 7 is a front view of the cutting state of the work piece produced by the first and first cutting edges of the ring cutter according to the first embodiment. Figures 8 (a) and (b) are the front view of the ring cutter described in the third embodiment, and the cutting state of the workpiece produced by the second cutting edge. These are two examples. Fig. 9 is a side view of a conventional ring cutter. Fig. 10 is a bottom view of a conventional ring cutter. Fig. 11 (a) is a front view of the first cutting edge of a ring-shaped tool, Fig. 11 is a front view of the second cutting edge, and Fig. 1 (c) is a view where the first cutting edge and the second cutting edge overlap Front view in the state. Fig. 12 (a) is the first cutting edge of a conventional ring cutter ['Fig. , Figure. 2 cuts 2 cuts

Cutting 5 (c) Cutting 2 cuts, in

11 (b) Cutter blade front view-21- 200406274, Figure 12 (b) is a front view of the second cutting edge, and Figure 12 (c) is a state where the first cutting edge and the second cutting edge overlap Front view. [Symbol description] 1 ... Circular tool 2 ... The tool body 3 ... The first cutting edges 3a, 5a ... Blades 3b, 5b ... Edges 3c, 5c at the outer end ... Edges at the inner end 4 ... 1st blade 4a, 6a ... 1st inclined surface 4b, 6b ... 2nd inclined surface PI, P2 ... vertex 5 ... 2nd cutting edge 6 ... 2nd blade 6 ... 3 Inclined surface 7 ... Segment 8 ... Chips discharge groove S1 ... Outside cutting edge! ] Range S2… Inner cutting range 5 3… Common cut angle U range -22-

Claims (1)

200406274 Scope of patent application 1. A ring cutter 'characterized in that a first cutting edge and a second cutting edge are alternately arranged at a predetermined interval in the circumferential direction of the bottom of the ring cutter having a cylindrical body; The cutting edge of the cutting edge is an inclined surface formed by vertices that are more peripheral than the central portion in the width direction of the cutting edge toward the upper ends of the two ends in the width direction. The cutting edge of the second cutting edge is formed by the edge of the first cutting edge. The vertex is an inclined surface formed by the apex of the peripheral end toward the upper ends of both ends in the width direction; on the inclined surface inclined from the vertex of the second cutting edge to the inner peripheral end, a plurality of inclines are formed discontinuously through the step portion. The surface of the 1st cutting edge and the 2nd cutting edge of the step formed on the inclined surface of the inclined surface of the 2nd cutting edge in front view are staggered with the inclined surface of the inner peripheral end of the 1st cutting edge Under the oblique surface of the peripheral end of the cutting edge of the first cutting edge when viewed from the front, the oblique surface inclined from the vertex to the peripheral end becomes the overlapping oblique surface. 2. A ring-shaped cutter characterized in that a first cutting edge and a second cutting edge are alternately arranged at a predetermined interval in the circumferential direction of the bottom of the ring-shaped cutting tool having a cylindrical body; the cutting edge system of the first cutting edge An inclined surface formed by a vertex arranged at a more peripheral end than a widthwise central portion of the cutting edge toward the upper ends of both ends in the width direction is formed at least on the inclined surface holding the inside of the vertex, with discontinuities due to step differences. A plurality of inclined surfaces formed; the blade edge of the second cutting edge is an inclined surface formed by an apex disposed more outward than the vertex of the first cutting edge toward the upper ends of both ends in the width direction, at least on the inner side holding the apex On the inclined surface, a plurality of inclined surfaces formed discontinuously due to the step difference are formed; at the point of 23-23200406274, do not look squarely at the difference between the blade edge of the i-th cutting edge and the edge of the second cutting edge, the first cutting edge The blade of the second cutting edge is set like the inclined surface of the cutting edge of the cutting edge formed on the other side; the blade of the first cutting edge is viewed from the front. End of the inclined surface, the inclined surface is inclined toward the peripheral edge of the bevel vertex of the cut lines overlap. 3. For the circular cutter of item 1 or 2 of the scope of patent application, the inner inclined surface is more inward than the apex of the first cutting edge and the second cutting edge, which are formed slightly parallel to each other. 4. For the ring cutter according to any of claims 1 to 3 in the scope of the patent application, when the first cutting edge is used as the outer edge and the second cutting edge is used, the cutting resistance of the workpiece generated by the outer edge and the inner edge The crop cutting resistance produced satisfies the following conditions: working cutting resistance produced by the outer edge > working object cutting resistance produced by the inner edge. 5. The ring knife according to any one of the items 1 to 4 in the scope of the patent application, in which the first cutting edge is used as the outer edge, the second cutting edge is used as the inner edge, and the shape of the outer edge and the inner edge (retraction angle) , Front angle) when the same, the cutting resistance of the cutting edge produced by the outer edge and the cutting resistance of the crop produced by the inner edge meet the following conditions: working cutting resistance generated by the outer edge > (working object cutting resistance generated by the outer edge) + Cutting resistance of the workpiece produced by the inner edge) / 2. The blade of the knife is formed outside the staggered edge, the cutting tool of the inner blade, the cutting tool of the occasion, the cutting tool of the occasion -24-