JP2511368B2 - Coolant supply method and device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for supplying a coolant to a cutting portion when a cutting tool such as an end mill, a ball end mill, a drill or a milling cutter is used in a machine tool such as a milling machine or a machining center. It relates to the device. In the present invention, the coolant means a fluid such as cutting fluid, pressurized air or the like which performs a cooling action and a chip discharging action. Further, the cutting tool is divided into a shank portion and a cutting edge portion, and both of these portions are collectively referred to as a tool body. Then, the cutting blade portion is further divided into a cutting blade portion in the middle and a cutting blade portion at the tip, and the cutting blade portion at the tip is, for example, in the case of a tool having a twisted cutting blade, a cutting blade that is the first cutting edge counted from the tool tip. Area.

[0002]

2. Description of the Related Art As a first prior art, for example,
The coolant flows from the rear end of the tool spindle described in JP-A 2-21403 to the inside of the tool spindle, and further through the tool holder attached to the tip of the tool spindle and the through hole of the tool to eject the coolant from the tool tip. There is so-called spindle through coolant. Also, instead of circulating the coolant inside the tool spindle, a fluid rotary joint is installed in the tool holder to feed the coolant into the tool holder from the outside and circulate it through the through hole of the tool attached to the tool holder and eject it from the tip of the tool. There is a so-called tool-through coolant that is designed to do so.

As for the structure of a cutting tool having a through hole used in these cases, an example of an end mill is disclosed in Japanese Utility Model Laid-Open No. 63-38917. That is, a through hole is formed so that a hole is formed in the axial center from the rear end of the tool and bifurcated just before the front end to open on the flank of the tool front end.

As a second conventional technique, an actual Kaihei 1-132 is used.
There is a tap for a casting hole described in Japanese Patent No. 327. This is a tap for a cast hole that penetrates the oil hole in the axial direction of the tap and has an oil groove communicating with the tap groove on the outer circumference of the shank.If tapping a blind hole, supply from the oil hole and oil groove. Both coolants serve lubrication, cooling and chip evacuation. When tapping the through hole, the coolant supplied from the oil hole will flow out of the work as it is, but since the coolant is supplied from the oil groove provided on the outer periphery of the shank, the effects of lubrication, cooling and chip discharge are effective. It is done in a regular manner.

As a third conventional technique, a real fair 4-274
There is an end mill described in Japanese Patent No. 3 publication. As shown in FIG. 1 of the publication, this is at the outer peripheral rear end of the end mill body 20,
A coolant supply groove 25 extending from the rear end side of the end mill body to the chip discharge groove 22 along the longitudinal direction of the end mill body.
Is formed, and air, oil, or the like is jetted toward the groove 25. As a result, chips can be smoothly discharged, and further, since there is no hole at the tip of the tool, re-grinding can be performed.

As a fourth conventional technique, Japanese Patent Laid-Open No. 4-253
There is a cutting method and an apparatus used therefor described in Japanese Patent Publication No. 09-09. This uses a tool made of ultrafine particle cemented carbide as a cutting edge of a tool, and a high-pressure fluid having a discharge pressure of 10 kg / cm ² or more is projected from a high-pressure water discharge nozzle toward a cutting point. As a result, the cutting point is instantly cooled by the high-pressure liquid, and the heat generated at the cutting point is hardly transmitted to the inside of the workpiece and the cutting tool cutting edge, so neither the workpiece nor the cutting edge is thermally damaged. That is.

[0007] As a fifth conventional technique, an actual flat blade 4-734
There is an oil supply device for a rotary tool in a machine tool described in Japanese Patent No. 40. However, this publication is not a publicly known material because it was published after the basic filing date of the domestic priority claim of the present application, but since it is a prior application of the present application, it will be described for reference. In the technique of this publication, a coolant oil supply passage is formed in a rotary member that rotates together with the tool, and an outlet side end of the oil supply passage is directed toward the outer circumference of the tool. Since the supplied coolant and the tool rotate at the same number of revolutions, the coolant is sufficiently reluded without being repelled by the rotating tool. Further, the positional relationship between the coolant and the tool does not change even when the X, Y, and Z feed movements are performed, and the coolant is always supplied to the set position of the tool.

[0008]

In the cutting process, a tool that is harder and stronger than the work is pressed against the work while performing a relative motion while a rotating force is applied to the work to generate chips by a shearing action to finish the work into a desired shape. is there. At this time, cutting heat is mainly generated by shearing work and friction work between the chip and the tool. This cutting heat is transmitted to the tool, shortens the life of the tool, and causes adverse effects such as forming a built-up edge to deteriorate the machined surface roughness. Therefore, it is necessary to quickly and surely cool the generated cutting heat with a coolant to eliminate these adverse effects. To do this, high-pressure coolant is sprayed on the shearing part of the work where chips are generated and the friction part between the chips and the rake face of the tool, and is cooled by the coolant before the generated cutting heat is transmitted to the tool and work. Chips that have been taken and that retain the cutting heat must also be blown away with the coolant. That is, the high-pressure coolant having a sufficient pressure and flow rate must be constantly jetted toward the cutting edge portion and its vicinity.

The first conventional technique is to supply the coolant as close as possible to the cutting portion. At that time, it is necessary to form a through hole through which the coolant flows inside the end mill, but in the case of a cemented carbide tool or the like, it is difficult to form this through hole. Also, in the case of a ball end mill or drill with a cutting edge at the center of the tool tip, it is necessary to form a through hole that is bent or bifurcated because it is necessary to open a through hole in the flank that avoids the cutting edge. Is more difficult. Furthermore, in the case of a small-diameter end mill, since the through hole is formed, the strength of the tool is lowered, and the cutting of the shaft portion and the chipping of the cutting edge are likely to occur. Further, there is a problem that the inner diameter of the through hole cannot be increased and a sufficient coolant flow rate cannot be secured.

The second prior art discloses a structure of a tap as a tool for thread cutting work, which is a relatively low speed cutting, in which the coolant supplied from the oil groove is low pressure and a small amount, and is accompanied by the rotation of the tap. It is preferable that the protrusions protrude from the oil groove and then penetrate into the threaded portion to be processed. On the other hand, cutting tools such as end mills, milling cutters, and drills cannot be applied with this conventional technique because they need to perform relatively high-speed cutting. In other words, in the case of a cutting tool such as an end mill that rotates at high speed, sufficient pressure,
A flow of high pressure coolant must be injected directly into the machined part. Therefore, there is a problem in applying the second conventional technique to a technique for supplying a coolant to a processing portion by a cutting tool such as an end mill, a ball end mill, a drill and a milling cutter.

In the third prior art, since the concave coolant supply groove is formed only up to the chip discharge groove closest to the shank portion, when the coolant is ejected at a high pressure along the coolant supply groove, the shank portion is formed. There is a disadvantage that the coolant is repelled by the cutting edge portion close to, and the coolant does not reach the cutting edge portion of the tool tip sufficiently. This problem is particularly noticeable in the case of commonly used processing such as relatively shallow grooving that uses only the end of the end mill, and processing that uses the cutting edge of the tip of a ball end mill or drill. There is a problem that proper cooling and quick chip discharge are not performed.

In the fourth prior art, since the coolant discharge nozzle is used, it is necessary to change the direction of the nozzle manually or automatically so that the coolant is injected to the cutting portion according to the diameter and length of the tool. is there. In addition, there are disadvantages that the nozzle and the work interfere with each other, and the setup work is hindered. Further, there is a problem that the coolant is not directly jetted to the cutting portion due to the work shape depending on the work shape and the processed portion.

In the fifth conventional technique, the oil supply passage outlet in the rotary member must be formed toward the outer circumference of the tool, and the injection angle of the oil supply passage outlet must be changed according to the tool length and the tool diameter. There is an inconvenience. Therefore, an object of the present invention is to solve the above-mentioned problem, that is, to supply a high-pressure coolant having a sufficient pressure and flow rate directly to a cutting portion regardless of the tool length and the tool diameter. A method and apparatus are provided.

[0014]

SUMMARY OF THE INVENTION Therefore, according to the present invention, in a method for supplying a coolant to a cutting portion, a cutting edge portion from a rear end of a shank portion to a cutting tool tip is provided on an outer periphery of a tool body of a cutting tool.
Engraving at least one linear concave coolant supply groove parallel to the rake face toward the rake face , mounting the cutting tool in a tool holder capable of introducing coolant, and applying a high pressure coolant Introduced into the coolant supply groove of the cutting tool, the coolant circulates in the coolant supply groove, and during cutting, the cutting edge of the cutting tool tip is always
A coolant supply method characterized in that coolant is ejected onto a rake face .

[0015]

According to the present invention, in the coolant supply device for the cutting portion, at least one straight line is formed on the outer periphery of the tool body from the rear end of the shank portion toward the rake face of the cutting edge portion at the tip, parallel to the axis. A cutting tool in which a concave coolant supply groove is engraved, a tool holder that is equipped with the cutting tool and is capable of introducing coolant into the coolant supply groove, and coolant is introduced into the tool holder at high pressure, A coolant supply device, comprising: a coolant supply source which is circulated through the coolant supply groove and is capable of being jetted to a rake face of a cutting edge portion of the tip of the cutting tool.

According to the present invention, in the coolant supplying device for the cutting portion, at least one linear concave shape is provided on the outer periphery of the tool body from the rear end of the shank portion toward the cutting edge portion of the tip in parallel with the axis. A cutting tool having a coolant supply groove engraved therein, a tool holder that is equipped with the cutting tool and is capable of introducing coolant into the coolant supply groove, and a draw bar that is provided with the tool holder mounted on a spindle. A coolant supply line that can be brought into and out of contact with the coolant supply hole inside, and a coolant is introduced into the tool holder through the coolant supply line at high pressure, and the coolant flows through a coolant supply groove provided in the cutting tool. And a coolant supply source capable of jetting to a cutting edge portion at the tip of the cutting tool.

[0018]

Further, according to the present invention, in a coolant supply device for a cutting portion, a collet having a slit groove for receiving and gripping a cutting tool is attached so that it can be tightened and loosened, and a coolant is introduced into a tool attachment hole of the collet. A tool holder made possible and a coolant introduced into the tool holder at a high pressure, and the coolant flows through the slits of the collet to grip the cutting tool along the outer periphery of the cutting tool. Provided is a coolant supply device including a coolant supply source adapted to eject toward a portion.

[0020]

The high-pressure coolant introduced into the tool holder by the spindle through coolant device or the tool through coolant device flows through the coolant supply groove of the cutting tool attached to the tool holder or along the outer periphery of the cutting tool. Gush out to. At this time, since the coolant supply groove is formed and opened parallel to the axis toward the cutting edge portion at the tip of the cutting tool, the coolant is always jetted so as to directly hit the cutting portion. The coolant is spouted at the same speed as the tool holder and the cutting tool, and with sufficient pressure and flow rate so that it is not blown in the outer peripheral direction by centrifugal force, so the cutting part is always cooled during cutting. It works to eject chips. Further, at this time, since the coolant passes through the coolant supply groove provided in the cutting tool, the coolant is surely ejected to the cutting portion without being disturbed by the work. Further, since the coolant is jetted in parallel along the outer circumference of the cutting tool, it is not necessary to change the jet angle depending on the tool length and the tool diameter.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram of a coolant supply device of the present invention, and FIG. 2 shows an example of an end mill used in the present invention.
3A is a front view, FIG. 3B is a sectional view taken along line AA of FIG.
Shows an example of a ball end mill used in the present invention,
4A is a front view, FIG. 4B is a sectional view taken along line BB of FIG.
Shows an example of a drill used in the present invention, (a) is a front view, (b) is a sectional view taken along line CC of (a), and FIG. 5 shows an example of a milling cutter used in the present invention. ) Is a front view,
7B is a sectional view taken along the line D-D of FIG. 6A, FIG. 6 is an explanatory view showing the action of the coolant of the present invention, and FIG. 7A is a main part configuration view showing another embodiment of the present invention. , (B) is a sectional view taken along the line EE, FIG. 8 (a) is a main part configuration diagram showing another embodiment of the present invention, and (b) is a sectional view taken along the line FF.

In FIG. 1, a tool spindle 1 is rotatably supported by a spindle housing 2 by bearings 3 and is rotated by a drive device (not shown). 4 is a bearing retainer. The tool holder 5 is attached to the tip taper hole of the tool spindle 1 by pulling up the pull stud 6 screwed to the rear end of the tool holder 5 with a draw bar 7. Reference numeral 8 is a key for positioning the tool holder 5 in the rotational direction. A pipe 9 is inserted into the draw bar 7 and the tip of the pipe 9 contacts the pull stud 6 to rotate integrally with the tool spindle 1. A fluid rotary joint 10 is provided at the rear end of the pipe 9, and the coolant discharged from the coolant supply source 11 is fed into the pipe 9.

On the other hand, the end mill 12 is detachably attached to the tip of the tool holder 5. On the outer periphery of the tool body of the end mill 12, a coolant supply groove 13 having a concave shape described later is formed up to just before the cutting edge at the tip. Pull stud 6,
The tool holder 5 has a through hole communicating with the pipe 9, and the coolant discharged from the coolant supply source 11 passes through the pipe 9, the pull stud 6 and the tool holder 5, and the coolant supply groove of the end mill 12. It is configured so as to flow through 13 and finally be ejected toward the cutting edge portion at the tip of the end mill 12.

FIG. 2 shows an end mill 12 used in the present invention. The one shown is a four-blade end mill having twisted cutting edges 14a, 14b, 14c, 14d and a clearance groove 15. A concave coolant supply groove is provided on the outer periphery of the shank 16.
13 from the rear end surface 17 of the end mill 12 parallel to the axis, through the cutting edge part in the middle, toward the tip of the cutting edge 14a, 14c 2
The book is engraved. The coolant supply groove 13 is divided into a portion 13a engraved on the shank portion, a portion 13b penetrating the cutting blade 14c, and a portion 13c penetrating the cutting blade 14b, but they are linearly connected to each other, and one groove is formed. I regard it as.

The cross-sectional shape of the coolant supply groove 13 is not limited to a square shape as shown in the drawing, but may be a semi-circular shape, a semi-elliptical shape, or any other shape. The diameter d of the depth portion of the two coolant supply grooves 13 is smaller than the outer diameter D of the cutting edge 14.
That is, the coolant supply groove 13 is cut deeper than the outer peripheral surface of the cutting edge portion. This is because the coolant supply groove 13 is open toward the cutting edge of the tip, that is, the extension line of the coolant supply groove 13 is configured to always hit the cutting edge portion 14 of the tool tip. . Therefore, in the end mill in which the outer diameter of the shank portion is formed larger than the outer diameter of the cutting edge portion, it is necessary to engrave a deep coolant supply groove. The sharp edges such as the intersection of the coolant supply groove 13b and the cutting edge 14c and the intersection of the cutting edges 13c and 14b are chamfered to prevent the cutting edge from chipping.

FIG. 6 shows a view in which the end mill 12 is attached to the tool holder 5. The shank 16 of the end mill 12 is mounted in the tool mounting hole 18 of the tool holder 5, and the coolant is
It passes through 19 and flows into the tool mounting hole 18. Then, the coolant flows through the two concave grooves 13 and 13 and is ejected toward the tip of the end mill 12. During machining by the end mill 12, the tool spindle 1, the tool holder 5, and the end mill 12 rotate together, and the coolant inside also rotates at a constant speed. Even when the main shaft is rotated at a high speed, the coolant is supplied at a high pressure (for example, 70 kg / cm ² ) at which the coolant ejected from the coolant supply groove 13 is reliably ejected at a high pressure to the cutting edge portion of the tool tip, The coolant ejected from the coolant supply groove 13 directly hits the cutting edge portion of the tool tip.

The cross-sectional area of the coolant supply groove 13 can be made larger than that of forming a hole inside the end mill, and the flow rate can be increased accordingly. Therefore, in any case, the coolant is always supplied to the cutting edge of the tool tip, that is, the cutting portion at a sufficient pressure and flow rate to rapidly absorb the cutting heat and discharge the chips. When performing deep groove processing or side surface processing that uses the entire cutting edge portion from the shank portion of the end mill 12, coolant leaks from the open portion between the coolant supply grooves 13a and 13b and between 13b and 13c. As a result, the coolant is supplied not only to the tip of the tool but also to the entire area of the cutting edge, so that the heat of cutting heat can be absorbed and the chips can be discharged for all kinds of machining.

As another embodiment, in the coolant supply device of FIG. 1, instead of the end mill in which the coolant supply groove 13 is engraved, a normal end mill having no coolant supply groove is mounted, and as shown in FIG. 7 or FIG. There is a coolant supply method in which a high pressure coolant (for example, 70 kg / cm ² ) is jetted in the tool tip direction along the outer circumference of the end mill using a tool holder.

A cutting tool (the end mill 12 in this embodiment) is gripped at the tip of the tool holder 5 of FIGS. 7 and 8, and the gripping method is a taper chuck type (FIG. 7) or a collet chuck type (FIG. 8). ) Two structures are disclosed. Referring to FIG. 7, the end mill 12 is fixed to the tool holder 5 by inserting it into the tool mounting hole 18 of the tool holder 5 and tightening a taper portion 25 at the tip of the tool holder with a ring 23. Tool mounting hole
18 communicates with the pipe 9 through the coolant supply hole 19 and the through hole of the pull stud 6, and the coolant can be introduced from the coolant supply source 11. Two concave grooves 24 are formed in the inner peripheral surface of the tool mounting hole 18 at positions opposite to each other by 180 ° parallel to the axis line up to the tip surface of the tool holder 5. When the end mill 12 is inserted into the tool mounting hole 18, the concave groove 24 becomes a coolant flow passage together with the outer peripheral surface of the end mill 12,
The coolant runs along the outer circumference of the end mill 12
Spouts toward the tip of.

Next, referring to FIG. 8, the end mill 12 is attached to the tool holder 5 by a collet chuck. The collet chuck is a collet divided into four by a slot 22 inside a ring 23 screwed to the tool holder 5.
21 is inserted, the ring 23 is rotated to expand or contract the inner diameter of the collet 21, and the end mill 12 is detachably mounted. The coolant from the coolant source 11 is
The pipe 9, the through hole of the pull stud 6, and the coolant supply hole 19 of the tool holder 5 can be introduced into the space in which the collet 21 is stored. Then slot 22
End mill along the outer circumference of the end mill 12
It is ejected toward the tip of 12. The action of the ejected coolant is similar to that in the case of FIG.

Although there is a method in which a conventional coolant discharge nozzle is provided outside an end mill that rotates at a high speed and the coolant is sprayed from the nozzle toward the end mill, it rotates at a substantially constant speed around the end mill that rotates at a high speed. There was an air layer, and it was difficult to break the air layer and directly apply the coolant to the rake face of the cutting edge portion of the end mill. In other words, the coolant was almost thrown out in the air layer.

According to the present invention, the coolant is circulated in the coolant supply groove formed in the end mill, or the coolant is jetted along the outer periphery of the end mill through the concave groove inside the tool holder or the slit portion of the collet. Since the end mill is rotated at a high speed, the coolant already exists inside the air layer surrounding the outer circumference of the end mill, and the coolant is jetted directly to the rake face of the cutting edge of the end mill without breaking the air layer. It is possible. Further, not only a liquid such as cutting fluid but also pressurized air may be used as the coolant, and this air may be jetted to cool the cutting edge portion and discharge the chips.

Since the coolant supply method and apparatus according to the present invention are configured in this manner, there is no difficulty in forming a through hole in a cutting tool, which is a problem of the prior art, and in the case of a small diameter tool, the through hole is formed. There is no longer a problem that the strength of the tool is insufficient and the sufficient flow rate of the coolant cannot be secured because the through hole has a small diameter. Further, the coolant that has flowed through the coolant supply groove or the outer periphery of the cutting tool is always jetted so as to directly hit the cutting edge portion. Furthermore, unlike the coolant supply by a coolant discharge nozzle provided outside, there is no need to adjust the nozzle angle manually or automatically, and depending on the shape of the workpiece and the machining site, the coolant is not projected directly to the cutting part, or The inconvenience that the coolant is repelled by the air layer that orbits the outer circumference of the cutting tool at a substantially constant speed has been resolved.

In this embodiment, the case where two coolant supply grooves or concave grooves are formed has been described, but if at least one coolant supply groove or concave groove is formed, a certain effect is exhibited. However, it is most desirable to provide as many coolant supply grooves as the number of cutting edges of the tool tip toward each cutting edge. Further, other types of tool holders may be used as long as the coolant is ejected along the outer periphery of the mounted cutting tool in the tool tip direction. Further, it goes without saying that a tool through coolant system in which coolant is introduced into the tool holder may be used instead of the spindle through coolant system.

Next, the ball end mill shown in FIG. 3 will be described. The ball end mill in FIG. 2 is a four-blade ball end mill, and is a diagram in the case where four coolant supply grooves 13 are also provided. The coolant supply groove 13 is formed in the shank portion 16 from the shank rear end face 17 in parallel with the axis of the shank 16 and in a straight line shape. The coolant supply groove 13 is opened toward the rake face of each of the cutting edge portions 14a, 14b, 14c, 14d. Also in this ball end mill, as described in the end mill shown in FIG. 1, the high pressure coolant passes through the coolant supply groove 13 and the cutting edge portion 14 of the tool tip.
Since it is sprayed toward the rake face of a, 14b, 14c, 14d, the action of the high pressure coolant not only removes the heat generated by the cutting of the cutting edge, but also directly hits the chips that are trying to adhere to the cutting edge. And then scatter. Therefore, the operation and effect are the same as those described for the end mill. Since they are duplicated here, the description is omitted.

Next, the case of the drill shown in FIG. 4 will be described. The coolant supply groove 13 is divided into two pieces so that the coolant supply groove 13 is parallel to the axis from the rear end surface 17 of the shank and linearly penetrates through the cutting blade portion in the middle to be opened toward the rake face of the cutting blade portion 14 at the drill tip. It is set up. It should be noted that in the figure, the alternate long and short dash line of 20 indicates the locus when the drill rotates.

Next, the case of the milling cutter of FIG. 5 will be described. As a typical example, a dovetail milling cutter is shown here. The shank 16 is provided with five coolant supply grooves 13 parallel to the axis and linearly from the rear end face 17 toward the rake face of the cutting edge portion 14 at the tool tip. With this structure, the coolant is always supplied to the rake face of the cutting edge portion.

[0038]

As described above, according to the coolant supply method and device of the present invention, the high pressure coolant which has been circulated in the coolant supply groove formed on the outer periphery of the shank of the cutting tool is directly attached to the rake face of the cutting edge portion. Since the high-pressure coolant is jetted so as to hit the cutting part, the high-pressure coolant having a sufficient pressure and flow rate is always supplied to the cutting part without being hindered by the shape of the cutting blade part or the workpiece in the middle. Further, the coolant ejected along the outer circumference of the cutting tool by the groove and the slit provided inside the tool holder is likewise reliably supplied to the cutting portion.

Therefore, the removal of the cutting heat and the discharge of the chips in the cutting section are carried out quickly and surely, so that the processing efficiency is improved, and the chips are caught, so that the highly accurate cutting can be carried out. Further, since the heat removal effect is large, the life of the cutting tool is extended, which is economical. Further, according to the present invention, since it is not necessary to change the jetting position and angle of the coolant depending on the length of the cutting tool and the tool diameter, automation is easy to achieve.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a coolant supply device of the present invention.

FIG. 2 shows an example of an end mill used in the present invention,
(A) is a front view, (b) is an AA sectional view of (a).

FIG. 3 shows an example of a ball end mill used in the present invention, (a) is a front view, and (b) is a BB sectional view of (a).

4A and 4B show an example of a drill used in the present invention, FIG. 4A is a front view, and FIG. 4B is a sectional view taken along line CC of FIG.

FIG. 5 shows an example of a milling cutter used in the present invention,
(A) is a front view, (b) is DD sectional drawing of (a).

FIG. 6 is an explanatory view showing the action of the coolant of the present invention.

7A and 7B show another embodiment of the present invention, in which FIG. 7A is a configuration diagram of a main part, and FIG. 7B is a sectional view taken along line EE.

8A and 8B show another embodiment of the present invention, in which FIG. 8A is a configuration diagram of a main part, and FIG.

[Explanation of symbols]

 1 Tool spindle 5 Tool holder 9 Pipe 10 Fluid rotary joint 11 Coolant supply source 12 End mill 13 Coolant supply groove 14 Cutting edge 16 Shank 18 Tool mounting hole 21 Collet 22 Slot 23 Ring 24 Recessed groove.

Claims (4)

(57) [Claims] 1. A method of supplying coolant to a cutting portion, wherein at least one straight line is provided on the outer periphery of the tool body of the cutting tool from the rear end of the shank portion toward the rake face of the cutting edge portion of the cutting tool tip in parallel with the axis. -Shaped and concave coolant supply groove is engraved, the cutting tool is mounted on a tool holder capable of introducing coolant, high-pressure coolant is introduced into the coolant supply groove of the cutting tool, and the coolant is the coolant. A coolant supply method, characterized in that the coolant is squirted through the supply groove to constantly spray the rake face of the cutting edge portion of the cutting tool tip during cutting. 2. A coolant supply device for a cutting portion, wherein at least one straight and concave shape is provided on the outer periphery of the tool body from the rear end of the shank portion toward the rake face of the cutting edge portion at the tip in parallel with the axis. A cutting tool having a coolant supply groove engraved, a tool holder equipped with the cutting tool and capable of introducing the coolant into the coolant supply groove, and a coolant introduced into the tool holder at a high pressure so that the coolant supplies the coolant. The cutting edge part of the tip of the cutting tool that flows through the groove
And a coolant supply source capable of jetting to the rake face of the coolant supply device. 3. A coolant supply device for a cutting portion, wherein at least one linear and concave coolant supply groove is provided on the outer periphery of the tool body from the rear end of the shank portion toward the cutting edge portion of the tip in parallel to the axis. A cutting tool having an engraved mark, a tool holder that is equipped with the cutting tool and is capable of introducing coolant into the coolant supply groove, and a drawbar that is provided in the drawbar that mounts the tool holder on a spindle, and the coolant in the tool holder is provided. A coolant supply conduit that can be brought into and out of contact with a supply hole, and a coolant is introduced into the tool holder through the coolant supply conduit at high pressure, and the coolant flows through a coolant supply groove provided in the cutting tool to perform the cutting. A coolant supply device, comprising: a coolant supply source capable of jetting to a cutting edge portion at a tip of a tool. 4. A coolant supply device for a cutting portion, wherein a collet having a slot groove for receiving and gripping a cutting tool is tightenably and loosely mounted, and coolant can be introduced into a tool mounting hole of the collet. A tool holder,
Coolant is introduced into the tool holder at a high pressure so that the coolant is jetted toward the cutting edge portion of the tip of the cutting tool along the outer circumference of the cutting tool which flows through the slot of the collet and is gripped. And a coolant supply source as described above.