KR101753218B1 - Cutting Tool for Beveling Hole - Google Patents

Abstract

The present invention has a cutting edge that is symmetrical forward and backward in correspondence with both holes formed on the same line of the workpiece, so that a connection that can be engaged with and secured to the tool table is provided so as to provide efficient inspecting of the inside edges of both side holes of the workpiece at one time. Shank; A hole guide shaft formed at one end of the connection shank and extending in the front axial direction so as to be able to enter the inside of the work hole; And a cutting part formed at one end of the hole guide shaft and capable of contacting the hole edge of the workpiece, the cutting part having a plurality of cutting edges on the outer periphery, wherein the cutting edge of the cutting part has a symmetrical structure And a chamfered end which is formed so as to chamferably contact the inner corner of the hole in correspondence with both side holes on the same line disposed before and after the workpiece.

Description

{Cutting Tool for Beveling Hole}

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a double-sided hole cutting tool, and more particularly, to a double-sided hole cutting tool having a cutting edge that is symmetrically back and forth corresponding to both holes formed on the same line of a workpiece, The present invention relates to a cutting tool for a double-sided hole cutting tool.

In general, various types of accessory components, such as automobile parts and machine parts, are processed to penetrate holes according to their applications and functions. In the case of hole edges machined on the workpiece, burrs generated during machining are removed And various types of chamfer cutting tools are used for a cutting operation in which a sharp end is curved.

As a conventional art disclosed in relation to a cutting tool for chamfering work described above, Korean Utility Model Publication No. 237539 (Jun. 26, 2001) discloses a drill hole drill for drilling a corner of a hole entrance, , The blade is made of a long bar-shaped cemented pin, the two long bar-shaped cemented pins are embedded in the rim, these three cemented pins are gathered at the end of the blade, A hole drilling drill is known which can be expected to improve the working efficiency in accordance with the above-mentioned conventional art.

In addition, in the registered patent publication No. 304414 (July 21, 2001), a cutting tool for a hole-chamfer provided with a guide blade and a replaceable cutting edge on a cutting part formed at the shank end of a body made of hard steel or alloy steel, There is known a cutting tool for a hole chamfer which can form a groove so that a guide blade made of a cemented carbide is slightly protruded and integrally formed by brazing and welding so that the cutting edge is not shaken and a precise cutting operation can be achieved.

Also, in Japanese Patent Registration No. 1555040 (Sep. 16, 2015), a body formed with a shaft hole passing through the center thereof; Wherein the first lateral margin of each first lateral edge of the lateral edge of the body is formed in a range of 10 to 20 degrees and the second lateral edge angle of the lateral edge of the second edge of the lateral edge of the body is in a range of 25 to 35 degrees A plurality of cutter blades to be formed; A discharge groove formed in the longitudinal direction between the cutter blades to discharge the chamfered chips; Wherein a width of the primary blade of the plurality of cutter blades is in the range of 0.7 to 0.8 mm and a width of the secondary blade of the secondary blade is in a range of 2.2 to 2.3 mm And the plurality of cutter blades are formed to have an edge angle in a range of 15 to 60 degrees. The body and the bag portion are connected to each other by brazing, thereby preventing a phenomenon of processing interference and trembling A take-off tool is known.

However, according to the conventional chamfering cutting tools, since the cutting edge is formed only at the front one end, only the edge of the hole exposed outside the workpiece among the through holes can be chamfered, and the inner edge portion of the workpiece can be machined In the case of a workpiece requiring precision machining, there is a problem in that it is difficult to connect the components through the through holes, resulting in defective products.

Further, in the case of conventional chamfer cutting tools, it is difficult to chamfer the workpiece formed with two holes on the same line so as to have only one-way machining capability, so that additional work such as changing the direction of the workpiece, There is a problem that the precision and the productivity of the product are lowered.

Registration Practical Utility Model No. 20-0237539 (Jun. 28, 2001) Patent Registration No. 10-0304414 (July 21, 2001) Patent Registration No. 10-1555040 (2015.09.16.)

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and it is an object of the present invention to provide a cutting edge having a symmetrically formed structure extending inwardly of a workpiece hole and effectively forming chamfered inner corner portions, It is an object of the present invention to provide a double-sided hole cutting insert tool capable of chamfering chamfered inner edges of both side holes.

A double-sided hole cutting cutting tool proposed by the present invention comprises: a connection shank which is fixedly connectable to a tool table; A hole guide shaft formed at one end of the connection shank and extending in the front axial direction so as to be able to enter the inside of the work hole; And a cutting part formed at one end of the hole guide shaft and capable of contacting the hole edge of the workpiece, the cutting part having a plurality of cutting edges on the outer periphery, wherein the cutting edge of the cutting part has a symmetrical structure And a chamfered end portion which is chamfered so that the inner corner of the hole can be chamfered corresponding to both side-by-side holes arranged in front of and behind the workpiece.

The cutting portion is formed with a total diameter of 6 mm, and the height of the cutting edge protruding outward is in a range of 1.2 to 1.5 mm.

The chamfered end portion is inclined downwardly inclined relative to the upper surface of the cutting edge, and the inclined surface inclination angle of the chamfered end portion is formed at 45 degrees with respect to the upper surface of the cutting edge.

The chamfered end portion is formed with a sloped inclined surface inclined downward in the direction of rotation of the cutting portion, and the inclined inclined surface is inclined at an angle of 10 to 12 degrees.

According to the cutting tool for cutting both sides of the hole according to the present invention, since it is possible to enter the inside of the hole of the workpiece and to form the cutting edge having the chamfered end of the structure symmetrical to each other so that the inner corner of the hole of the workpiece can be chamfered, It is possible to improve the quality of the machining and to prevent defects between the joined products by performing complete burr removal and chamfering around the holes while expanding the functionality. Further, chamfering of the inner edges of the both side holes formed on the same line disposed before and after the workpiece makes it possible to shorten the machining time, thereby improving the productivity of the machining as well as raising the precision of chamfer machining.

1 is a perspective view showing an embodiment according to the present invention;
2 is a front view showing an embodiment according to the present invention;
3 is an enlarged view of a cutting portion in an embodiment according to the present invention;
4 is a side view showing a cutting portion in an embodiment according to the present invention.
5 (a) and 5 (b) are diagrams showing examples of use states of an embodiment according to the present invention, respectively.

The present invention relates to a connecting shank which is fixedly connectable to a tool table; A hole guide shaft formed at one end of the connection shank and extending in the front axial direction so as to be able to enter the inside of the work hole; And a cutting part formed at one end of the hole guide shaft and capable of contacting the hole edge of the workpiece, the cutting part having a plurality of cutting edges on the outer periphery, wherein the cutting edge of the cutting part has a symmetrical structure And a chamfered end portion formed so as to be rotatable in contact with the inner corner of the hole in correspondence with both side holes formed in the front and rear of the workpiece and aligned in the same line.

BEST MODE FOR CARRYING OUT THE INVENTION Next, a preferred embodiment of a double-sided hole cutting tool according to the present invention will be described in detail with reference to the drawings.

1 and 2, an embodiment of a double-sided hole cutting tool according to the present invention includes a connection shank 10, a hole guide shaft 20, and a cutting portion 30 .

The connection shank 10, the hole guide shaft 20, and the cutting portion 30 are integrally formed using a cemented carbide.

The connecting shank 10 has a cross-sectional shape such as a circular shape, a square shape, and a hexagonal shape, and is formed to extend in the longitudinal and longitudinal directions.

A tapered inclined surface 15 inclined downward toward the hole guide shaft 20 is formed at one end of the connection shank 10 at a connection point with the hole guide shaft 20, 20, it is possible to improve the self-durability of the tool.

The tapered inclined surface 15 is formed such that the inclination angle? 1 is 30 degrees with respect to the outer circumferential surface of the connecting shank 10.

The hole guide shaft 20 is integrally formed at one end of the connecting shank 10 and extends in the axial direction so that it can enter the hole 7 of the workpiece 5 during chamfering. That is, the hole guide shaft 20 is interconnected between the connection shank 10 and the configuration of the cutting portion 30, and the cutting portion 30 is positioned in the inner space of the workpiece 5, Thereby further extending the length.

The hole guide shaft 20 can be formed to have a circular cross section, a quadrangular cross section, or a hexagonal cross section in the same manner as the connection shank 10, but has a circular sectional shape due to the fact that it enters into the circular through hole 7 So that it is possible to achieve a smooth machining while preventing collision with the workpiece 5, which is preferable.

The connection shank 10 is formed to have a length L1 of 50 to 55 mm and a diameter D1 of 10 mm while the hole guide shaft 20 has a length L2 of 35 to 40 mm and a diameter D2 of 3.5 mm The hole guide shaft 20 can be smoothly introduced into the hole 7 having a limited size of the workpiece 5 and the inner diameter of the hole guide shaft 20 can be increased It is possible to extend the tool life by promoting the structural balance of the tool having the tool.

The cutting portion 30 is formed at one end of the front side of the hole guide shaft 20 and can be contacted with the edge of the hole 7 of the workpiece 5 to perform chamfering.

As shown in Figs. 1 and 4, the cutting portion 30 is provided with a plurality of (four in Fig. 4) cutting edges 35 arranged radially on the outer periphery.

The cutting portion 30 has a total diameter D3 of 6 mm and a turning radius larger than a diameter D2 of the hole guide shaft 20 of 3.5 mm. The height H of the cutting edge 35 projecting radially outward is in the range of 1.2 to 1.5 mm so that the hole guide shaft 20 is inserted into the hole 7 of the workpiece 5 during chamfering It is possible to smoothly chamfer the inner edge of the hole (7) of the work (5) along the cutting edge (35) of the cutting portion (30) while preventing a collision phenomenon.

As shown in Figs. 2 and 3, the cutting edge 35 of the cutting portion 30 is formed symmetrically with respect to both the front and rear ends of the cutting edge 30, and the inner edge of the hole 7 of the workpiece 5 is chamfered (37).

The chamfered end portion 37 is chamfered to be in contact with the inner hole 7 of the workpiece 5. When the hole 7 of the workpiece 5 is arranged in the front and rear coaxial shapes, Since the chamfered end portions 37 having a symmetrical structure corresponding to the chamfered portions 7 are in contact with each other in a back and forth sequence, the corners of the inner hole 7 of the work 5 can be chamfered collectively.

3, the chamfered end portion 37 forms an inclined surface inclined downward outward with respect to the upper surface of the cutting edge 35 so as to chamfer the corner portion of the hole 7 of the workpiece 5 do.

The inclination angle alpha 1 of the downward inclined inclined surface of the chamfered end portion 37 is formed to be 45 degrees with respect to the upper surface of the cutting edge 35. [

As shown in FIG. 4, the chamfered end portion 37 of the cutting edge 35 is formed with a beveled inclined face 38 inclined downward in the rotational direction of the cutout 30, It guides you to be smooth.

The pickled inclined surface 38 is formed to form an angle of inclination? 2 in the range of 10 to 12 degrees.

When the incline inclination angle alpha 2 of the cutting edge of the cutting edge 35 is less than 10 deg., Inclination for guiding the discharge of chips is small and the inclination angle alpha 2 of the pickled inclined surface 38 exceeds 12 deg. The discharge direction of the chip is directed to the other cutting edge 35 due to the rapid inclination, so that the chip is not smoothly discharged.

The hole guide shaft 20 is provided at one end of the cutter 30 which is in contact with the hole guide shaft 20, that is, at the chamfered end 37 located rearward of the chamfered end 37 of the cutting edge 35 And a guide groove (39) extending from the guide groove (39).

The guide groove 39 is formed by a length of 1/2 of the length of the cutting edge 35 and forms a gentle curved surface toward the outside.

When the guide groove 39 is formed as described above, the chip is positioned behind the cutting edge 35 and smoothly discharges the chip in the area closed by the hole guide shaft 20 when the workpiece 5 is brought into contact with the workpiece 5 It is possible to guide.

5, when the connecting shank 10 of the cutting tool is coupled to the tool holder, a chamfering operation is started. At this time, The cutting portion 30 moves toward the inside through the hole 7 of the workpiece 5 after the workpiece 7 approaches the machined workpiece 5. [ The cutting edge 35 of the cutting portion 30 comes close to the inner edge of the hole 7 of the workpiece 5 so that the edge of the chamfered end portion 37 of the cutting edge 35 The chamfered end portion 37 formed on the front side contacts the edge of the hole 7 located at the front side and chamfering is performed, so that the upper chamfering processing proceeds. 5 (b), the chamfered end portion 37 formed at the rear of the chamfered end portion 37 of the cutting edge 35 comes into contact with the edge of the hole 7 located at the back, And the machining is completed.

That is, according to the double-sided hole cutting tool according to the present invention configured as described above, it is possible to form a cutting edge having a chamfered end portion that is capable of entering the inside of the hole of the workpiece and is symmetrical with respect to the inner corner of the hole of the workpiece. Therefore, it is possible to improve the quality of the machining by eliminating the burrs and chamfering around the holes while expanding the functionality for the chamfering process, and it is possible to prevent defects between the combined products beforehand. Further, since the inner edges of both side holes formed on the same line disposed before and after the workpiece are collectively chamfered, it is possible to shorten the machining time, thereby improving machining productivity and raising the precision of chamfering.

While the present invention has been described in connection with certain preferred embodiments thereof with reference to the accompanying drawings, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, And is also within the scope of the present invention.

10: connection shank 15: taper slope
20: Hole guide shaft 30: Cutting part
35: cutting edge 37: chamfered end
38: pickled slope 39: guide groove
L1: Connection shank length L2: Hole guide shaft length
D1: Connection shank diameter D2: Diameter of hole guide shaft
D3: Overall diameter of cutting edge H: Height of cutting edge
α1: chamfered end inclination angle α2: inclined inclined angle
? 1: Tapered inclined surface inclination angle

Claims (4)

A connection shank fixedly coupled to the tool table; A hole guide shaft formed at one end of the connection shank and extending in the front axial direction so as to be able to enter the inside of the work hole; And a cutting part formed at one end of the hole guide shaft and capable of contacting the hole edge of the workpiece, the cutting part having a plurality of cutting edges on the outer periphery, wherein the cutting edge of the cutting part has a symmetrical structure And a chamfered end portion formed so as to chamferably contact the inner corner of the hole in correspondence with both side-by-side holes arranged in the front and rear of the workpiece,
Wherein the connection shank is formed with a tapered inclined surface inclined downward at an angle of inclination of 30 ° toward the hole guide shaft at a connection point with the hole guide shaft,
Wherein the cutting portion is formed to have a total diameter of 6 mm, and the cutting edge has a height of 1.2 to 1.5 mm protruding outward, and the cutting portion is provided with one end, which is in contact with the hole guide shaft, And a guide groove extending from the cutting edge by a length of 1/2 of the length of the cutting edge and forming a curved surface toward the outside,
Wherein the chamfered end portion is inclined downwardly inclined relative to the upper surface of the cutting edge, and the inclined angle of the inclined surface of the chamfered end portion is set to 45 degrees with respect to the upper surface of the cutting edge,
Wherein the chamfered end portion is formed with a sloped inclined surface inclined downward in the rotating direction of the cutting portion, and the inclined inclined surface is inclined at an angle of 10 to 12 degrees.
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