KR20020050976A - Drill with an indexable solid insert - Google Patents

Abstract

PURPOSE: A drill is provided to reduce the manufacturing cost thereof by simplifying the manufacturing process of a drill insert and to facilitate the centering work when the drill insert is coupled to a drill body. CONSTITUTION: A drill(100) includes a drill body(120) and a drill insert(140) detachably attached to a front end of the drill body(120). The drill body(120) has a handle part for fixing the drill(100) to a machine tool or an arbor and a blade part(124) which extends in a spiral pattern towards a front portion of the drill body(120). A flute(126) is formed radially outward of the blade part(124). The flute has a spiral shape. The flute(126) extends between the handle part and the front portion of the drill body(120) so as to discharge chip or supply oil. An insert seat(125) is formed at an inner front portion of the drill body(120) for receiving the drill insert(140) therein.

Description

Drill with an indexable solid insert

The present invention relates to a drill tool used for hole processing during cutting, and more particularly, to improve the coupling structure of the front end of the drill body and the indexable solid insert detachably coupled thereto, thereby exhibiting excellent machining precision. It is an economical indexable insert drill that can be replaced only with inserts that are inexpensive and end of life.

The drill is used to drill the workpiece. The initial drill was an integrated solid drill consisting of the drill body, chip discharge flute, and tip cutting blade made of one material.In order to reduce tool cost, At the end of the life of the insert, an indexable drill has been developed that uses the drill body and replaces the insert with a new one. The indexable drill developed in this way was mainly using two inserts. However, since the precision of the hole after machining was inferior to that of the solid drill, there was a limitation in applying it for precision machining.

6A-7B illustrate a drill with indexable solid inserts according to the prior art.

First, as shown in FIGS. 6A and 6B, the conventional drill 10 includes a drill body 20 and a drill insert 30 mounted to the tip of the drill body 20. The drill body 20 includes a bag 22 and a blade 24, and the fitting hole 21 through which cutting oil flows is formed at the inner center of the bag 22 and the blade 24. An oil hole 23 is formed inside the tip end of the drill body 20, and the oil hole 23 extends radially outward from the fitting hole 21 so as to communicate with the fitting hole 21. On the radially outer side of the blade portion 24, a flute 26 of a spiral groove shape is formed. An installation groove 25 is formed inside the front end of the drill body 20, and a plurality of fastening holes 27 are symmetrically formed at a side intermediate position of the installation groove 25.

The drill insert 30 has a main cutting edge 32 and a web cutting edge 34 on the top surface. In the adjacent position of the web cutting edge 34, a flute 36 corresponding to the flute 26 of the blade portion 24 is formed. A fixing groove 38 is formed at one lower side of the drill insert 30.

In the conventional drill 10 configured as described above, the drill insert 30 is inserted into the installation groove 25 formed at the front end of the drill body 20. In this state, the tightening bolt 28 is inserted into the fastening hole 27 to fix the drill insert 30. At this time, the tip portion of the tightening bolt 28 penetrating the fastening hole 27 is in close contact with the fixing groove 38 of the drill insert 30 to support the drill insert 30.

However, in the conventional drill 10 having such a structure, the method of matching the center of the drill insert 30 to the center of the drill body 20 is uncertain, and thus becomes a problem when the drill insert 30 is initially fastened or replaced, and the fastening force is reduced. weak. As a result, there was a problem of degrading the quality of the processed product. In addition, since the oil hole 23 is formed between the inner wall surface and the bottom surface of the installation groove 25, a part of the oil hole 23 is blocked when the drill insert 30 is mounted in the installation groove 25. As a result, the flow of cutting oil is not smoothly performed, and thus, the wear of the main cutting edge 32 and the web cutting edge 34 of the drill insert 30 is severe.

The product developed to solve this problem is the drill shown in Figs. 7a and 7b.

The conventional drill 40 shown in FIGS. 7A and 7B has a drill body 50 and a drill insert 60 mounted to the tip of the drill body 50. The drill body 50 has a bag portion 52 and a blade portion 54, and a fitting hole 51 through which cutting oil flows is formed in the inner center of the bag portion 52 and the blade portion 54. On the radially outer side of the blade portion 54, a flute 56 having a spiral groove shape is formed. An installation groove 55 is formed inside the distal end of the drill body 50, and an oil hole 53 is formed at an intermediate position of an inner surface of the installation groove 55 and a radial outer surface of the drill body 50. In this case, the oil hole 53 extends in the inner longitudinal direction from the top of the drill body 50, and is connected to the fitting hole 51 inside the drill body 50. Then, a plurality of fastening holes 57 are formed symmetrically in the lower side of the installation groove 55 in the front end portion of the drill body 50. At this time, the fastening hole 57 is formed to be inclined at a predetermined angle with respect to the fitting hole 51.

The drill insert 60 has a main cutting edge 62 and a web cutting edge 64 on the top surface. In the adjacent position of the web cutting edge 64, a flute 66 corresponding to the flute 56 of the blade portion 54 is formed. The lower portion of the drill insert 60 is formed by protruding a cylindrical fitting portion 65 by a predetermined length. The fitting portion 65 has an outer diameter smaller than the inner diameter of the fitting hole 51 formed in the drill body 50. A fixing groove 68 is formed at one side of the outer surface of the fitting portion 65.

The conventional drill 40 configured as described above mounts the drill insert 60 to the installation groove 55 formed at the tip end of the drill body 50, wherein the fitting portion 65 of the drill insert 60 is drilled to the drill body 50. ) Into the fitting hole (51). In this state, the tightening bolt 58 is inserted into the fastening hole 57 to fix the drill insert 60. At this time, the tip portion of the tightening bolt 58 penetrating the fastening hole 57 is in close contact with the fixing groove 68 of the drill insert 60 to support the drill insert 60.

However, in the conventional drill 40 having such a structure, the centering of the drill insert 60 is good, but the fitting portion 65 is configured to protrude in a cylindrical shape from the drill insert 60 body. Production is difficult, there is a problem that the precision processing of the fitting portion 65 and the installation groove 55 is difficult. In addition, since the oil hole 53 meets the inclined angle close to the fitting hole 51 in the drill body 50, there is a problem that the flow of cutting oil is not smoothly made.

In other words, the conventional drills 10 and 40 mentioned above have a short rotation preventing surface of the drill bodies 20 and 50 to sufficiently endure the rotating torques received by the drill inserts 30 and 60 at high speed. There was a problem that the life of the drill body (10, 40) is reduced due to lack of durability.

The present invention has been made to solve such a conventional problem, an object of the present invention to improve the coupling structure of the front end of the drill body and the indexable solid insert detachably coupled thereto, the drill insert is to be fastened to the drill body It is to provide a drill having an indexable solid insert that can be made at a good centering, and easy to manufacture a drill insert can be manufactured at a lower cost than a conventional solid drill.

It is another object of the present invention to design a screw insertion hole for receiving a fixed screw for supporting a drill insert mounted at the tip of the drill body such that the drill insert is twisted in the opposite direction of rotation about the center of rotation of the drill insert, so that the drill insert is drilled. The present invention provides a drill having an indexable solid insert that is firmly fastened to and does not generate vibration during drill cutting.

In addition, another object of the present invention is to drill the cutting oil supply hole in the upper portion of the drill body at a gentle angle toward the center of the drill body and to communicate smoothly to the center oil hole in the drill body, thereby smoothing the supply path of the cutting oil to supply the cutting oil The present invention provides a drill having an indexable solid insert which can be made smoothly, and as a result, tool life and hole machining accuracy can be improved to ensure excellent productivity.

1 is an exploded perspective view of a drill having an indexable solid insert according to a preferred embodiment of the present invention;

2a and 2b is a perspective view of the engaged state of the drill shown in FIG.

3 is a view of the indexable solid insert shown in FIG. 1 from various angles, FIG.

4 is a plan view of the drill shown in FIG.

5A is a longitudinal sectional view taken along line A-A of FIG. 4;

5B is a longitudinal sectional view taken along line B-B of FIG. 4;

5C is a cross-sectional view taken along the line C-C of FIG. 4, and

6A-7B illustrate a drill with indexable solid inserts according to the prior art.

<Explanation of symbols for the main parts of the drawings>

10,40,100: drill 20,50,120: drill body

21,51: fitting hole 23,53,123: oil hole

25,55: mounting groove 26,36,56,66,126,145a, 145b: flute

27,57 fastener 28,58 tightening bolt

30,60,140: Drill insert 38,68,143a, 143b: Fixing groove

65: fitting portion 111a, 111b: body side

113a, 113b: Body bottom surface 115a, 115b: Body clearance

117a, 117b: body thinning surface 121: center oil hole

125: insert sheet 127a, 127b: screw insertion hole

128a, 128b: fixed screw 146a, 146b: bottom surface

147a, 147b: outer circumference

The present invention to achieve the above object,

And a drill insert detachably mounted to a drill body and a tip of the drill body, wherein the tip portion of the drill body is formed by cutting an insert sheet for receiving the drill insert, and the drill body is formed of a bag and the A blade extending spirally from a bag to the tip end of the drill body, a spiral groove-shaped flute is formed on the radially outer side of the blade, and a central oil hole is formed at the inner center of the drill body. It is formed through the direction, and the left and right sides of the insert sheet is formed with an oil hole and a screw insertion hole in the tip portion of the drill body, the drill insert is provided with pickled, pickled clearance surface, flute, outer peripheral surface, side and bottom surface In a drill having an indexable solid insert,

The insert sheet has a vertical body side and a bottom surface, wherein the bottom surface of the insert sheet meets at an inclined angle with respect to each other from radially outer side to the inner side of the drill body, so that the entire center portion is recessed. Has a V-shape to enter, wherein the bottom surface of the drill insert has a V-shape protruding from the center portion so as to correspond to the bottom surface of the insert sheet, and at the tip end of the drill body. Both sides of the insert sheet are provided with a body clearance surface and a body thinning surface, an oil hole is formed in the body clearance surface, and the oil hole extends inclined in the longitudinal direction of the drill body from the body clearance surface to the drill body. Communicate with the central oil hole in the inner side of the body clearance surface Bottom of the body's ningmyeon is to provide a drill having a block index solid insert, characterized in that formed through the ball screw that is inserted into the fixing screw.

As mentioned above, the drill according to the present invention, unlike the existing indexable drill, the bottom surface of the drill insert and the insert sheet bottom surface, which is a fastening surface of the drill body, are configured to correspond to each other in a V shape. As a result, when the drill insert is fastened to the tip of the drill body, the centering is good and the production is simple. In addition, by three-dimensionally original design of the screw insertion hole of the fixing screw for supporting the drill insert mounted on the tip of the drill body, it is possible to obtain excellent fastening force. In addition, by drilling the oil hole for cutting oil supply on the clearance side of the drill body and smoothly connecting it to the central oil hole formed inside the drill body, a sufficient amount of cutting oil can be smoothly supplied, thereby cutting the heat generated during drilling. It can effectively reduce and discharge cutting chips smoothly.

Hereinafter, a drill having an indexable solid insert according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

The present invention seeks to develop a drill with a new concept of indexable solid inserts that can achieve excellent precision and tool cost savings.

To this end, in the present invention, the indexable solid insert is firmly fixed to the drill body, the centering method of accurately matching the center axis of the drill insert to the center axis of the drill body, the method of smoothly supplying the coolant, and the rotation generated during the drilling process. How to secure the durability of the drill body to withstand the torque sufficiently, How to secure the durability of the drill body that can withstand the thrust force generated in the opposite direction of the feed when drilling, and manufacture the drill insert precisely and easily, making it relatively low cost compared to the solid drill Focused on the development of ways to make it easier.

1 is an exploded perspective view of a drill having an indexable solid insert according to a preferred embodiment of the present invention, and FIGS. 2A and 2B are views illustrating the coupling state.

1, 2a and 2b, the drill 100 according to a preferred embodiment of the present invention is provided with a drill insert 140 that is detachably mounted to the front end of the drill body 120 and the drill body 120. do.

The drill body 120 spirals from the bag 122 and bag 122 to the tip of the drill body 120 to secure the drill to a machine tool (not shown) or an arbor (not shown). It has a blade portion 124 extending to. On the radially outer side of the blade portion 124 is formed a flute 126 of the spiral groove shape. The flute 126 is formed to extend between the tip portion of the bag 122 and the drill body 120 for chip discharge and coolant supply.

The insert sheet 125 for accommodating the drill insert 140 is formed inside the distal end of the drill body 120 by cutting. The insert sheet 125 has vertical body sides 111a and 111b and body bottom surfaces 113a and 113b formed to correspond to the bottom mounting surface of the drill insert 140. At this time, the body bottom surface 113a and 113b meet while inclining by a predetermined angle to face each other from the radially outer side of the drill body 120 to the inside. Accordingly, the body bottom surfaces 113a and 113b have a V-shape in which a central portion thereof is recessed. Preferably, the body bottom surfaces 113a and 113b have an inclination angle θ of 80 to 170 ° symmetrically with respect to the central axis of rotation of the drill body 120 (see FIG. 5C).

If the inclination angle formed by the body bottom surfaces 113a and 113b is less than 80 degrees, the central axis of rotation of the drill insert 140 coincides with the central axis of rotation of the drill body 120 (hereinafter referred to as "centering"). Easy to do, but the V-shaped sheet surface formed by the depth of the deeper there is a problem that the force that can withstand the rotational torque of the anti-rotation surface is weakened. On the other hand, when the inclination angle formed by the body bottoms 113a and 113b is 170 degrees or more, the drill insert 140 of the drill insert 140 that is fastened due to its low durability against thrust force generated near the rotational center portion during drilling is formed. The central axis is off the central axis of the drill body 120, and as a result, vibration and breakage of the drill insert 140 may occur during drilling.

On the other hand, both sides of the insert sheet 125 at the front end of the drill body 120 to smooth the chip discharge from the body clearance surface (115a, 115b) and the rotation center of the drill to prevent interference between the workpiece and the body during cutting Body thinning surfaces 117a and 117b are provided.

The screw insertion holes 127a and 127b penetrate through the lower portions of the body clearance surfaces 115a and 115b and the body thinning surfaces 117a and 117b at the distal ends of the drill body 120. Screw insertion holes 127a and 127b Fixing screws 128a and 128b for fastening the drill insert 140 to the tip end of the drill body 120 are fitted therein.

4 is a plan view of the drill shown in FIG. 1, FIG. 5A is a longitudinal cross-sectional view taken along line A-A of FIG. 4, and FIG. 5B is a longitudinal cross-sectional view taken along line B-B of FIG. 4.

4, 5A and 5B, the screw insertion holes 127a and 127b are formed in three dimensions to tightly fix the drill insert 140 to the tip of the drill body 120. In explaining the theoretical background, when the drill insert 140 is mounted in the insert sheet 125 of the drill body 120, the fixing screws 128a and 128b have a center of rotation of the drill insert 140. The drill insert 140 should not be separated from the drill body 120 when the drill 100 comes out of the workpiece after the drilling process. In addition, when the drill insert 140 is fastened to the distal end of the drill body 120, the side surfaces 148a and 148b (see FIG. 3) of the drill insert 140, which will be described below, are the body side surfaces 111a of the insert sheet 125. And (b) firmly adhere to each other, so that vibration does not occur during drilling.

Accordingly, in order for the side surfaces 148a and 148b of the drill insert 140 to closely adhere to the body side surfaces 111a and 111b of the insert sheet 125 formed at the distal end portion of the drill body 120, the screw insertion holes 127a, 127b) is formed at a position eccentrically by the eccentric play L3 and the eccentricity angle α with respect to the central axis of the drill body 120. The eccentric play L3 is a distance between the centerline of the screw insertion holes 127a and 127b and the center axis of the drill body 120, and preferably in the range of 1 to 5 mm. The eccentric angle α is preferably 10 to 45 degrees with respect to the y-axis. In addition, the screw insertion holes 127a and 127b are arranged in the y-axis direction, that is, in the direction of the bag 122 of the drill body 120 in order to prevent the drill insert 140 from being deviated in the axial direction of the drill body 120. In order to achieve a fixed angle β of 5 to 25 degrees.

The fixing screws 128a and 128b fastened to the screw insertion holes 127a and 127b are tightly fitted into the fixing grooves 212a and 212b of the drill insert 140 when the fastening is completed.

On the other hand, in the initial drilling, the cutting edge portion of the drill insert 140 is exposed to the outside during the initial drilling entry, but when entering into a depth of 2mm or more, the cutting edge portion enters into the machined hole and is not visible. It is very difficult to supply cutting oil to solve the reduction of cutting heat, chip evacuation, and the like. Therefore, it is very important to smoothly supply the cutting oil near the drill insert 140 during the drilling process performed in the hole. At this time, the coolant should have a sufficient amount of cutting oil supplied and sufficient pressure.

In the present invention, in order to solve the problem of the cutting oil, basically the center oil hole 121 through which the cutting oil flows in the inner center of the bag portion 122 and the blade portion 124 is formed. Then, the oil holes 123a and 123b are drilled in the body clearance surfaces 115a and 115b of the drill body 120 so that sufficient cutting oil is supplied to the cutting edge portions 201a and 201b of the drill insert 140 during cutting. .

The oil holes 123a and 123b are for supplying cutting oil to cool the cutting heat generated during the drilling process and to smoothly discharge the cutting chips. The oil holes 123a and 123b may be provided at the inside of the tip of the drill body 120 to form the sheet 125 of the drill insert 140. It is formed in the body clearance surface 115a, 115b which is a both position. At this time, the oil holes 123a and 123b extend in the inner longitudinal direction of the drill body 120 from the body clearance surfaces 115a and 115b. The oil hole 123 extends inclined radially inward of the drill body 120 to be connected to the central oil hole 121 in the drill body 120.

Specifically, the oil holes 123a and 123b have a constant clearance L2 with the drill insert 140 so as to prevent interference with the side anti-rotation surface of the drill insert 140 and are fixed from the center of the drill body 120. The distance L1 is formed. The clearance L2 is a distance between the body side surfaces 111a and 111b of the insert sheet 125 and the center of the oil holes 123a and 123b, and is preferably in the range of 1 to 8 mm. Next, the distance (L1) is a distance from the center of the drill body 120 to the center of the oil holes (123a, 123b), the drill insert 140 which is a reference plane for determining the diameter of the drill 100 according to the present invention It is preferable to set in the range of 0.2D-0.45D with respect to the outer diameter D which the outer peripheral surfaces 147a and 147b of () make.

At this time, the diameter Φd of the oil holes 123a and 123b is 0.07 to 0.2D, and the oil holes 123a and 123b are 20 to 60 degrees based on the center of the oil holes 123a and 123b and the Y axis of the drill tip. It is punctured in the range of angle δ. In addition, the direction of the oil holes 123a and 123b is drilled at an angle of gamma γ in the rotation center direction of the drill body 120 with respect to the center of the oil holes 123a and 123b to rotate the drill body 120. In communication with the central oil hole 121 drilled in the center. At this time, the angle γ is advantageously to reduce the angle as much as possible to minimize the initial pressure and quantitative loss of the cutting oil from the central oil hole 121 via the oil holes 123a and 123b. If there is a problem that the manufacturing is difficult due to interference with the V-shaped body bottom surface of the drill insert 140. Therefore, it is preferable to select angle (gamma) in the range of 10-30 degree.

The cutting oil supplied through the center oil hole 121 and the oil holes 123a and 123b formed as described above reduces cutting heat during cutting, and the body clearance surfaces 115a and 115b of the drill body 120 and the body thinning surface ( It is discharged via the flutes 145a and 145b of the drill insert 140 and the flute 126 of the drill body 120 to be described below via the 302a and 302b. The coolant discharged in this way reduces the cutting heat of the cutting chip cut by the pickles 141a and 141b of the drill insert 140 and facilitates the discharge of the cutting chip.

3 is a view of the indexable solid insert shown in FIG. 1 viewed from various angles.

1 and 3, the drill insert 140 is detachably fastened in the insert sheet 125 formed at the tip end of the drill body 120, pickled on the top surface (141a, 141b), pickled clearance surface ( 142a and 142b and thinning surfaces 144a and 144b. Pickling (141a, 141b) is the primary contact with the workpiece during the drilling process using the drill 100 to perform the function of cutting the workpiece in the hole processing. Pickling clearance surfaces 142a and 142b serve to prevent interference between picklings 141a and 141b and the workpiece during drilling. The thinning surfaces 144a and 144b facilitate the cutting of the central portion during drilling and facilitate the ejection of the cutting chip.

Bottom surfaces 146a and 146b of the drill insert 140 form the V-shape as a whole as the most important part of the present invention. That is, the bottom surfaces 146a and 146b form an angle with respect to each other so that the bottom boundary portion 146c, which is the boundary between them, protrudes.

Side surfaces 148a and 148b are provided between the bottom surfaces 146a and 146b and the pickles 141a and 141b, which are anti-rotation portions 301a and 301b formed at the distal end of the drill body 120. Corresponds to the side seat surfaces 311a and 311b.

Fixing grooves 143a and 143b for firmly fixing the drill insert 140 in the insert sheet 125 of the drill body 120 are formed at one lower end of the side surfaces 148a and 148b, respectively. Flutes 145a and 145b are formed outside the side surfaces 148a and 148b at positions adjacent to the fixing grooves 143a and 143b for discharging the cut discharge chips to the outside. The flutes 145a and 145b extend from the outside of the side surfaces 148a and 148b between the bottom surfaces 146a and 146b and the top of the drill insert 140 to correspond to the flutes 126 formed in the drill body 120. do.

The outer circumferential surface 147b and the outer circumferential clearance surface 149b are provided between the side surface 148a and the flute 145b, and the outer circumferential surface 147a and the outer circumferential clearance surface 149a are provided between the side surface 148b and the flute 145a. do. The outer circumferential surfaces 147a and 147b serve as reference planes for determining the diameter of the drill, and the outer circumferential clearance surfaces 149a and 149b are for preventing excessive friction between the outer circumferential surfaces 147a and 147b and the workpiece during drilling.

The drill insert 140 configured as described above is inserted into and inserted into the insert sheet 125 formed by cutting the tip portion of the drill body 120. At this time, the bottom surfaces 146a and 146b protruding in the V-shape of the drill insert 140 are in close contact with the body bottom surfaces 113a and 113b recessed in the V-shape of the insert sheet 125. At the same time, the side surfaces 148a and 148b of the drill insert 140 are brought into close contact with the body side surfaces 111a and 111b of the insert sheet 125.

In this state, the fixing inserts 128a and 128b are inserted into the screw insertion holes 127a and 127b formed at the distal end of the drill body 120 to fix the drill insert 140 to the distal end of the drill body 120. At this time, the front end portions of the fixing screws 128a and 128b through which the screw insertion holes 127a and 127b protrude toward the insert sheet 125 are formed in the fixing grooves 143a and 143a formed in the side surfaces 148a and 148b of the drill insert 140. 143b). Thus, the fixing screws 128a and 128b strongly support the drill insert 140.

As such, the drill 100 in which the drill insert 140 is mounted is provided in the direction in which the drill insert 140 is forced and the fixing screws 128a and 128b are drill insert 140, as indicated by the arrow in FIG. 4 during drilling. Since the direction of the force for supporting the same is the same, a strong clamping force is applied so that vibration does not occur, thereby improving machining accuracy. In addition, since the oil holes 123a and 123b formed at the inner side of the drill body 120 and the oil clearances 115a and 115b of the drill body 120 are optimally connected to each other. In the cutting operation, a sufficient amount of cutting oil is smoothly supplied toward the cutting edge of the drill insert 140. As a result, tool life is improved and machining precision is improved.

As described above, the drill 100 manufactured according to the present invention, unlike the conventional indexable drill, inserts which are fastening surfaces of the bottom surfaces 146a and 146b of the drill insert 140 and the drill body 120. By forming the sheet bottom surfaces 113a and 113b to correspond to each other in a V-shape, centering is good and manufacturing is easy when fastening the drill insert 140 to the tip of the drill body 120. In addition, when the rotary torque and thrust received by the pickles 141a and 141b of the two drill inserts 140 are transmitted to the drill body 120, the drill body 120 and the drill insert 140 are transmitted in opposite directions. The rotating torque and the thrust cancel each other at the contact portion, so that the drill insert 140 and the body 120 of the drill are actually engaged in the same state, that is, in the same state as a solid drill. Thus, the durability of the drill body 120 is excellent, it is possible to minimize the rotation shake even in high-speed rotation, high feed drilling.

In addition, the three-dimensional original design of the screw insertion holes (127a, 127b) of the fixing screws (128a, 128b) for supporting the drill insert 140 mounted to the front end of the drill body 120, excellent fastening force You can get it.

In addition, by drilling the cutting oil supply holes (123a, 123b) on the free end portions (115a, 115b) of the drill body 120, and gently connected to the center oil hole 121 formed inside the drill body (120), A sufficient amount of cutting oil can be smoothly supplied to effectively reduce the cutting heat generated during the drilling process and to smoothly discharge the cutting chips. As a result, it is possible to secure excellent productivity by improving tool life and hole machining accuracy.

In addition, the drill 100 according to the present invention improves the shape of the cut portion of the drill insert 140 and through high-speed high-speed drilling of general steel, such as carbon steel, alloy steel, etc., through proper selection of materials (= based on sintered cemented carbide) Excellent machinability can be obtained in machining, hole machining accuracy is good and service life is also excellent.

In addition, it shows excellent performance in drilling processing of aluminum composite material, which is easy to weld and chip discharge is a problem. In addition, it has a good coolant supply in machining of stainless steel, hardened steel, etc., improves the chip discharging capacity, generates less heat and reduces the work hardening, thereby obtaining an excellent drilling effect.

Finally, since one drill insert 140 is replaced and used in one drill body 120, when the drill insert 140 is worn, the drill body 120 is used as it is and the drill insert 140 is used. Only new can be replaced, resulting in a reduction in tool costs.

In addition, the shape of the cutting edge portion of the insert drill according to the present invention can be applied to the indexable solid insert end mill or the indexable solid ball nose end mill by making the shape of the lower edge and the outer circumferential edge.

Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art will be able to variously modify and change the present invention without departing from the spirit and scope of the invention described in the claims below. It will be appreciated.

Claims (9)

And a drill insert 140 detachably mounted to a drill body 120 and a tip of the drill body 120, and an insert for accommodating the drill insert 140 at the tip of the drill body 120. The sheet 125 is formed by cutting and the drill body 120 has a bag portion 122 and a blade portion 124 spirally extending from the bag portion 122 toward the tip portion of the drill body 120. A spiral groove-shaped flute 126 is formed at a radially outer side of the blade 124, and a central oil hole 121 is formed at the inner center of the drill body 120 in the longitudinal direction of the drill body 120. Is formed to penetrate, the oil hole (123a, 123b) and the screw insertion holes (127a, 127b) are formed in the front end of the drill body 120 on the left and right sides of the insert sheet 125, the drill insert 140 Pickled (141a, 141b), pickled clearances (142a, 142b), seed Indexable with faces 144a and 144b, flutes 145a and 145b, outer peripheral surfaces 147a and 147b, outer peripheral clearance surfaces 149a and 149b, side surfaces 148a and 148b and bottom surfaces 146a and 146b In the drill 100 having a solid insert, The insert sheet 125 has vertical body side surfaces 111a and 111b and bottom surfaces 113a and 113b, wherein the bottom surfaces 113a and 113b of the insert sheet 125 are the drill body 120. Are inclined at a constant inclination angle with respect to each other from the radially outer side to the inner side thereof, and thus have a V-shape in which the center portion is recessed as a whole, and the bottom surfaces 146a and 146b of the drill insert 140 The V-shaped shape of the center portion protrudes to correspond to the bottom surfaces 113a and 113b of the insert sheet 125, and both sides of the insert sheet 125 at the distal end of the drill body 120. Body clearance surfaces 123a and 123b and body thinning surfaces 117a and 117b are formed, and oil holes 123a and 123b are formed in the body clearance surfaces 123a and 123b, and the oil holes 123a and 123b. ) The drill body from the body clearance surfaces 123a and 123b. Extend inclined in the longitudinal direction of the inner body 120 in communication with the central oil hole 121 in the inner side of the drill body 120, the body clearance surface (123a, 123b) and the body thinning surface (117a, 117b) The drill having an indexable solid insert, characterized in that the screw insertion hole (127a, 127b) through which the fixing screw (128a, 128b) is fitted through the bottom of the). According to claim 1, wherein the body bottom surface (113a, 113b) of the drill body 120 forms an inclination angle of 80 to 170 degrees symmetrically with respect to the central axis of rotation of the drill body 120, the drill insert When the 140 is mounted in the insert sheet 125 of the drill body 120, the bottom surfaces 146a, 146b of the drill insert 140 are the body bottom surface of the drill body 120 ( In contact with 113a and 113b, and the side surfaces 148a and 148b of the drill insert 140 are in close contact with the body side surfaces 111a and 111b of the insert sheet 125. Equipped with drill. The method of claim 1, wherein the side surface (148a, 148b) of the drill insert 140 is formed with fixing grooves (143a, 143b) in a position close to the bottom surface (146a, 146b) of the drill insert 140 When the drill insert 140 is mounted in the insert sheet 125 of the drill body 120, the drill insert 140 is inserted into the screw insertion holes 127a and 127b to protrude into the drill body 120. A drill having an indexable solid insert, characterized in that the distal end of the fixing screw (128a, 128b) is in close contact with the fixing groove (143a, 143b) to support the drill insert (140). The oil hole (123a, 123b) has a constant gap (L2) with the drill insert 140 to prevent interference with the side surfaces (148a, 148b) of the drill insert 140. Drill having an indexable solid insert, characterized in that formed at a constant distance (L1) from the center of the drill body (120). The distance L2 is a distance between the body side surfaces 111a and 111b of the insert sheet 125 and the center of the oil holes 123a and 123b, and is in the range of 1 to 8 mm. L1 is a distance from the center of the drill body 120 to the center of the oil holes 123a and 123b and is 0.2 to the outer diameter D formed by the outer circumferential surfaces 147a and 147b of the drill insert 140. A drill having an indexable solid insert, which is set in the range of D to 0.45D. The diameter of the oil holes (123a, 123b) is 0.07 ~ 0.2D, the oil holes (123a, 123b) is the center of the oil holes (123a, 123b) and the drill body 120 of the It is drilled in the range of 20 to 60 degrees angle δ with respect to the Y axis of the tip portion, and the direction of the oil holes 123a and 123b is based on the center of the oil holes 123a and 123b. Drill having an indexable solid insert, characterized in that the angle (γ) of 10 to 30 degrees in the direction of the center of rotation, and communicates with the central oil hole (121) inside the drill body (120). The method of claim 1, wherein the screw insertion holes (127a, 127b) is formed in a position eccentrically by a certain eccentric play (L3), a constant eccentric angle (α) with respect to the central axis of the drill body (120). Drill with indexable solid insert. According to claim 7, wherein the eccentric play (L3) is a distance between the center line of the screw insertion holes (127a, 127b) and the central axis of the drill body 120 ranges from 1 to 5mm, the eccentric angle (α) is Drill with indexable solid insert, characterized in that it comprises an angle of 10 to 45 ° relative to the y-axis. According to claim 7, wherein the screw insertion holes (127a, 127b) is 5 to 25 degrees in the y-axis direction to prevent the drill insert 140 is separated from the axial direction of the drill body 120 A drill having an indexable solid insert, characterized by a fixed angle β.