KR200383648Y1 - Drill with an indexable solid insert - Google Patents

Abstract

By improving the joining structure of the front end of the drill body and the indexable solid insert that is detachably attached to it, it is possible to show excellent machining precision, and it is possible to replace only the insert which is inexpensive and end-of-life. Is disclosed. According to the present invention, the bottom surface of the insert sheet formed at the tip of the drill body and the bottom surface of the drill insert detachably mounted to the insert sheet are configured in a V shape so as to correspond to each other, and support the drill insert. The screw insertion hole for accommodating the fixed screw is designed in a conical shape, and when centering the drill insert to the front end of the drill body, the centering is good, easy to manufacture and can secure excellent fastening force. In addition, by drilling the oil hole for cutting oil supply on the clearance side of the drill body and smoothly communicating it with the central oil hole inside the drill body, it is possible to supply a sufficient amount of oil smoothly to effectively reduce the cutting heat generated during drilling. It is possible to smoothly discharge the cutting chips. As a result, it is possible to secure excellent productivity by improving tool life and hole machining accuracy.

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 showing 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.

In order to solve such a conventional problem, there is a Korean Patent Application No. 2000-80292 filed in the name of the present applicant.

However, in the present invention, there was a question in terms of economics by using a bidirectional fixing screw.

The present invention has been made to solve such a conventional problem, the object of the present invention is 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.

Another object of the present invention is to taper the screw insertion hole for receiving the fixed screw for supporting the drill insert mounted on the tip of the drill body, so that the drill insert is firmly fastened to the drill body, so that vibrations during the cutting process An object of this invention is to provide a drill having an indexable solid insert which does not occur.

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

Still another object of the present invention is to provide a tapered fixing screw fastened to the tapered screw insertion hole.

The present invention to achieve the above object,

An oil hole formed on the insert sheet and the clearance surface, a body thinning surface, and a screw insertion hole formed at an upper side thereof, and having a blade portion and a drill body flute, the drill body having a lower bag portion;

An insert which is accommodated in the sheet portion of the drill body, and has a pickled portion, a picked margin surface, a thinning surface chip flute, an outer circumferential surface, an outer circumferential margin surface, side and bottom surfaces, and a screw insertion hole formed therein;

In the drill having an indexable solid insert consisting of an insert accommodated in the insert sheet of the body and the fixing screw for fastening the body through the screw insertion hole of the body and the screw insertion hole of the insert, the insert sheet of the drill body is It has a vertical body side and a V-shaped bottom surface which is inclined at an angle to face each other from the radially outer side to the inner side of the drill body, the oil hole extends in the longitudinal direction of the inner side of the body and communicates with the central oil hole from the inner side of the body. Become;

The bottom surface of the insert has a V-shaped protruding center portion to correspond to the insert sheet bottom surface,

The fixing screw provides an indexable solid insert composed of a head, a first body, a second body, a third body and a thread.

Here, one side of the screw insertion hole of the screw insertion hole of the body is formed with a screw thread, the other side is formed in a tapered shape without the thread formed,

The screw insertion hole of the insert is tapered in cross-section with a larger diameter than the other side, and the first and third body portions of the fixing screw are tapered in cross section to reinforce the fastening force.

In addition, the bottom surface of the body is preferably formed to face at an angle of inclination angle (θ) of 80 to 170 °,

When the insertion hole is tightened, the eccentric clearance L3 of the screw center line CL2 and the thread center line CL3 is in the range of 0.01 to 0.3 mm, and the eccentric angle α forms an angle of 0 to 45 ° based on the X axis. To enhance the tightening force.

In addition, the insertion hole is such that when the central axis (A) and the screw center line (CL3) is fastened to make an angle of 90 ° fixing angle (β), the taper angle (η) of the third body of the fixing screw is 0 When the tapered angle of the first body of the fixing screw is in the range of 20 to 180 degrees, the body has a fixing screw insertion hole and the insert has a screw insertion hole. Only one side of the insert contacts the fixing screw and the opposite side of the fixing screw contacts only one side of the body so that the insert is firmly fixed to the body when fully tightened.

In addition, the diameter d1 at the center of the insert fixing groove is larger than the screw diameter d2 at the center of the insert when screwing, and the clearance d1-d2 is 0.1 to 3.0 mm.

The direction of the oil hole is formed at an angle (γ) of 10 ~ 130 ° in the direction of the center of rotation of the drill body relative to the center of the oil hole, the oil hole has a gap (L2) of the insert and 1 ~ 8㎜ range In addition, it is preferable to configure such that it has a distance (L1) in the range of 0.2D ~ 0.45D with respect to the outer diameter (D) of the outer peripheral surface of the drill insert from the center of the drill body.

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

1 and 2, a drill 100 according to a preferred embodiment of the present invention includes a drill body 140 and a drill insert 140 that is detachably mounted to a tip end of the drill body 120. .

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, a spiral body-shaped drill body flute 126 is formed. The flute 126 extends between the bag 122 and the tip of the drill body 120 for chip discharge and cutting oil 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 side portions 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 prevent interference between the workpiece and the body during cutting, and to discharge the chip from the body clearance surface (115a, 115b) and rotation center of the drill for preventing rotation Body thinning surfaces 117a and 117b are provided for smoothing.

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. A screw is formed in the screw insertion hole 127a, and a screw is not formed in the screw insertion hole 127b. A fixing screw 130 is fitted into the screw insertion holes 127a and 127b for fastening the drill insert 140 to the tip end of the drill body 120. The fixing screw 130 is composed of a head portion 131, a first body portion 132, a second body portion 133, a third body portion 134 and a screw portion 135, the first body portion 132 and the third body portion 134 is formed in a tapered shape.

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

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. This is because when the drill insert 140 is mounted in the insert sheet 125 of the drill body 120, the fixed screw 130 has a center of rotation of the drill insert 140 coinciding with the center of rotation of the tip of the drill body 120. And the drill insert 140 is not separated from the drill body 120 when the drill 100 exits from the workpiece after drilling. 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 portions 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 be in close contact with the body side surface portions 111a and 111b of the insert sheet 125 formed at the tip end portion of the drill body 120, the screw insertion holes 127a, 127b) is formed at a β angle on the central axis of the drill body 120 and an α angle on the X axis. The eccentric clearance L3 is preferably in the range of 0.01 to 0.3 mm as a distance between the fixed screw center line CL2 and the center line CL3 of the screw insertion hole 127a (see Fig. 5A) when fully tightened. The center line of the screw insertion holes 127a and 127b preferably forms an angle of α (0 to 45 °) with respect to the X axis. In addition, the screw insertion holes 127a and 127b have the drill insert 140 at the center axis A of the drill body 120 and the screw center line CL2 (see FIG. 5a) at the β angle. ° is preferred.

Meanwhile, the fixing holes 143a and 143b in the insert into which the third main body 133 of the fixing screw 130 is inserted are formed at a taper angle η of 0 to 30 ° of the third main body 134, but the third main body 134 When larger than the diameter of the fastener, one side of the screw 130 and the insert 140 is not in contact (L5) only the opposite side is in contact (T1). In addition, the screw insertion hole 127b into which the screw 130 and the first body 132 are inserted among the screw insertion holes 127a and 127b of the body is formed at a taper angle of 20 to 180 ° of the first body 132. However, when the first body 133 is slightly larger than the diameter of the first body 133, the first body 132 and the body screw insertion hole 127b corresponding to the first body 132 are not in contact with each other (L4). The V-shaped seat surface and the bottom surface of the body is tightly fixed.

As a result, as shown in Fig. 5a, the diameter d1 at the center of the insert 140 fixing groove is larger than the diameter d2 at the center of the insert when the screw is fastened, and the clearance d1-d2 is preferably about 0.1 to 3.0 mm. .

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 cutting oil, a central oil hole 121 through which cutting oil flows is formed in the inner center of the bag 122 and the blade 124. 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 cut portions 141a and 141b 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 holes 123a and 123b extend inclined radially inwardly 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 10-30 degree range.

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 insert 130 is inserted into the screw insertion holes 127a and 127b formed at the front end of the drill body 120 to fix the drill insert 140 to the front end of the drill body 120.

As such, the drill 100 having the drill insert 140 mounted therein is screwed 135 of the fixed screw 130 to the screw insertion hole 127a of the body 120 as shown in FIG. 5A during drilling. At the same time, the third body 134 pushes the force downward in the direction in which the insert 140 receives the force, and the screw on the insertion hole 127b is forced upward, so that a strong fastening force is applied, so that vibration does not occur. And thus the machining precision is improved. 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 deceased is an insert which is a fastening surface of the bottom surfaces 146a and 146b of the drill insert 140 and the drill body 120, unlike the existing indexable drill. 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, by ingeniously designing the screw insertion holes 127a and 127b of the fixing screw 130 for supporting the drill insert 140 mounted at the tip end of the drill body 120 in a tapered shape, an excellent fastening force can be obtained. .

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 the appropriate selection of the material (= based on sintered cemented carbide), high-speed high-speed drilling of general steel, such as carbon steel, alloy steel 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 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 peripheral edge.

Although described above with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and modified within the scope of the invention without departing from the spirit and scope of the present invention described in the utility model registration claims below It will be appreciated that it can be changed.

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

Figure 2 is a perspective view of the coupled 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;

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

FIG. 5C is a sectional view along line C-C in FIG. 4; FIG.

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

111a, 111b: side portions 113a, 113b: bottom surface

115a, 115b: clearance surface 117a, 117b: thinning surface

121: central oil hole 122: bag,

123a, 123b: oil hole 124: blade

125: insert sheet 126: drill body flute

127a, 127b: screw insertion hole 130: fixed screw

131: head portion 132: first body portion

133: second body portion 134: third body portion

135: thread 140: insert

143: screw fixing holes 148a, 148b: insert side

Claims (8)

The insert sheet 125, the clearance surfaces 115a and 115b, the body thinning surfaces 117a and 117b, and the screw insertion holes 127a and 127b are formed on the upper portion, and the blade 124 and the drill body flute 126 are provided. A drill body (120) consisting of a lower bag portion (122); It is accommodated in the sheet 125 of the drill body, pickled portions 141a, 141b, pickled free surfaces 142a, 142b, thinning surfaces 144a, 144b, chip flutes 145a, 145b, and outer peripheral surfaces 147a, 147b. ) And an insert 140 having outer peripheral surfaces 149a and 149b, side surfaces 148a and 148b, and bottom surfaces 146a and 146b and having a screw insertion hole 143 formed therein; The insert 140 and the body 120 accommodated in the insert sheet 125 of the body 120 are screw insertion holes 127a and 127b of the body 120 and the screw insertion hole 143 of the insert 140. In the drill 100 having an indexable solid insert made of a fixing screw 130 for fastening through The insert sheet 125 of the drill body 120 is perpendicular to the inner side surfaces 111a and 111b and the radially outer side of the drill body 120 so as to face each other inclined at an angle to meet the bottom surface 113a. , 113b), Bottom surfaces 146a and 146b of the insert 140 have a V-shape protruding from the center portion so as to correspond to the bottom surfaces 113a and 113b of the insert sheet 125. The fixing screw 130 is provided with an indexable solid insert, characterized in that consisting of at least one tapered portion and the threaded portion (135). The method of claim 1, Of the screw insertion holes 127a and 127b of the body 120, one side of the insertion hole 127a is formed with a thread, and the other side is formed in a tapered shape without the thread formed, The insert portion 143 of the insert 140 is tapered in cross section having a diameter larger than one side at one side thereof, and the tapered portions of the fixing screw 130 are formed in the first body portion 132 and the third body portion 134. Drill with indexable solid insert, characterized in that. The method according to claim 1 or 2, Bottom surface (113a, 113b) of the body 120 is drill having an indexable solid insert, characterized in that facing at an angle of inclination angle (θ) of 80 ~ 170 °. The method according to claim 1 or 2, The insertion holes 127a and 127b have an eccentric clearance L3 of 0.01 to 0.3 mm based on the central axis of the drill body 120 when fastened, and an eccentric angle α of 0 to 45 ° based on the X axis. Drill having an indexable solid insert, characterized in that formed to form. The method of claim 4, wherein The insertion hole (127a, 127b) is a drill having an indexable solid insert, characterized in that the center axis (A) and the screw center line (CL2) is made at an angle of 90 ° fixed angle (β) when fastening. The method according to claim 1 or 5, The taper angle η of the third body 133 of the fixing screw 130 is 0 to 30 °, and the taper angle of the first body 132 of the fixing screw 130 is 20 to 180 °. The body 120 has fixing screw insertion holes 127a and 127b corresponding to the fixing screw 130, and the insert 140 also has a screw insertion hole corresponding to the fixing screw 130. 143, a part of the fixing screw 130 and the screw insertion hole 143 are in contact with each other (T1), a part of the screw insertion hole 127b and the fixing screw 130 in contact (T2) A drill having indexable solid inserts, each opposite side having play (L4, L5). The method of claim 6, The insert 140 has a diameter d1 at the center of the fixing groove, and when the screw is fastened, the diameter d1 is larger than the diameter d2 at the center of the insert. Drill. The method of claim 1, Oil holes 123a and 123b are formed on the clearance surfaces 115a and 115b of the body 120, and the directions of the oil holes 123a and 123b are based on the centers of the oil holes 123a and 123b. It is formed at an angle (γ) of 10 to 30 ° in the direction of the center of rotation of the body 120, the oil holes (123a, 123b) has a gap (L2) of the insert 140 and 1 ~ 8mm range and drill Indexable solid insert, characterized in that it has a distance (L1) in the range of 0.2D ~ 0.45D with respect to the outer diameter (D) formed by the outer peripheral surface (147a, 147b) of the drill insert 140 from the center of the body 120 Drill having.