JP2020069584A - Body for cutting edge replacement type rotating tool and cutting edge replacement type rotating tool - Google Patents

Abstract

To provide a body for a cutting edge replacement type rotating tool which allows for improvement of cutting edge cooling capability.SOLUTION: A body 20 is provided that rotates with a rotation axis as a center. In the body 20, there are formed a chip seat 22A on which a cutting insert 40A for a drill is mounted, a supply part 28A for supplying a coolant from the outside, a flow path which is formed inside the body 20 and through which the coolant supplied from the supply part 28A flows, and a jetting part 24A which communicates with the chip seat in order to bring the coolant flowing through the flow path into contact with a side surface or a bottom surface of the cutting insert 40A opposing to the chip seat 22A.SELECTED DRAWING: Figure 1

Description

  TECHNICAL FIELD The present invention relates to a body for a cutting edge-changing type rolling tool and a cutting edge-changing type rolling tool.

  BACKGROUND ART Conventionally, there is known a technique of injecting a coolant from the tip of a tool body (also referred to as a holder or a body) in order to cool the blade edge of a blade tip exchange type cutting tool such as a blade tip exchange type drill. The coolant sprayed from the tip of the tool body flows through the gap between the bottom surface of the hole formed by a drill or the like and the tip surface of the tool, and is supplied to the cutting edge.

  Further, there is known a technique in which a coolant injection port is formed on the wall surface of a chip discharge groove and the coolant is sprayed toward a cutting edge.

  Patent Document 1 discloses a technique of spraying a coolant from a first coolant liquid ejection hole toward a tip cutting edge in a drill.

  Further, Patent Document 2 discloses an insert for a drill that secures chip discharge properties and suppresses the generation of cracks due to chip abrasion.

Micro film of Jitsukaihei 1-64319 JP, 2018-47532, A

  However, the cooling capacity so far has been insufficient in cooling capacity.

  Therefore, it is an object of the present invention to provide a body for a cutting edge exchange type cutting tool and a blade edge exchange type cutting tool which have a higher cooling effect than conventional ones.

  A cutting insert type cutting tool body according to an aspect of the present disclosure may have a cutting insert attached to a tip thereof. Then, by rotating around the rotation axis, the work piece can be processed. A tip seat for mounting the cutting insert and a supply portion for supplying the coolant from the outside are formed on the body. In addition, a flow path for flowing the coolant supplied from the supply unit is formed inside the body. Further, when the cutting insert is attached, the second injection part for bringing the coolant into contact with the exposed end surface of the cutting insert, and the coolant flowing through the flow path are brought into contact with the side surface or the bottom surface of the cutting insert facing the tip seat. Therefore, the injection part communicating with the tip seat is formed. The supply unit and the injection unit are, for example, holes formed on the surface of the body. The injection part may directly inject the coolant toward the end face of the cutting insert, or may form the injection part on the front end face so that the coolant colliding with the surface to be processed is brought into contact with the end face of the cutting insert.

  Further, on the seat surface of the tip seat, which is opposed to the bottom surface of the cutting insert, a groove may be formed which communicates with the injection portion and allows the coolant to flow along the bottom surface of the cutting insert.

  In addition, the cutting edge replaceable rolling tool body according to another aspect of the present disclosure may have a cutting insert attached to the tip. Then, by rotating around the rotation axis, the work piece can be processed. The body has a tip seat for mounting a cutting insert. Further, when the cutting insert is attached, a jetting portion communicating with the tip seat is formed in order to bring the coolant flowing through the inside of the body into contact with the side surface or the bottom surface of the cutting insert facing the tip seat. Further, in order to bring the coolant flowing through the inside of the body into contact with the end surface of the cutting insert, an injection portion communicating with the tip surface of the body is formed. The supply unit and the injection unit are, for example, holes formed on the surface of the body.

  Further, a cutting edge exchange type cutting tool according to one aspect of the present disclosure includes a cutting edge exchange type cutting tool body and a cutting insert.

Perspective view of indexable drill Right side view of body for indexable drill Left side view of body for indexable drill

  Embodiments of the present invention will be described below with reference to the drawings. The following embodiments are examples for explaining the present invention, and are not intended to limit the present invention only to the embodiments.

  Further, the present invention can be variously modified without departing from the gist thereof. For example, the present invention may be applied by removing or modifying some of the additional components in an embodiment within the ordinary creative ability of those skilled in the art.

  FIG. 1 is a perspective view of a replaceable cutting edge drill 10. 2 and 3 are a right side view and a left side view, respectively, when the front end view of the body 20 from which the cutting inserts 40A and 40B are removed is taken as a front view, and FIG. 2 is a seating surface 22A3 described later, or When the cutting insert 40A is attached, it corresponds to an end view as seen from a direction facing the end surface 40A1, and FIG. 3 shows a seating surface 22B3 described later or the cutting insert 40B when the cutting insert 40B is attached. This corresponds to an end view as seen from the direction facing the end surface of 40B.

  The drill 10 includes a body 20 and two cutting inserts 40A and 40B attached to the tip of the body 20.

  The body 20 is configured to be rotatable about a rotation axis AX, and includes a cylindrical base end portion 20B and a tip end portion 20A that is integrally formed with the base end portion 20B and grips the cutting inserts 40A and 40B. To be done.

  As shown in FIG. 2, a tip seat 22A for gripping the cutting insert 40A is formed at the end of the tip portion 20A in the rotation axis AX direction. The tip seat 22A includes a wall surface 22A1 oriented in the direction of the rotation axis AX, that is, the front end direction of the body 20, and a wall surface 22A2 oriented in the direction perpendicular to the rotation axis AX, ie, the outer diameter direction of the body 20, and the rotation axis A seating surface 22A3 is provided which is perpendicular to the AX and faces the traveling direction in which the body 20 rotates. Further, the connection portion connecting the seat surface 22A3 and the wall surface 22A1 and the connection portion connecting the seat surface 22A3 and the wall surface 22A2 are respectively recessed 22A5 and recess 22A6 which are formed so as to be recessed inward by carving the body 20. Is formed. A screw hole 22A4 is formed in the center of the seat surface 22A3 so as to open substantially vertically to the seat surface 22A3. Note that, as illustrated in FIG. 2, a surface facing a predetermined direction is not limited to a plane having that direction as a normal line, and a plane facing a predetermined direction or a curved surface is generally used. Say that.

  On the other hand, as shown in FIG. 1, the cutting insert 40A includes an end face 40A1 that functions as a rake face and faces the rotation direction, a side face 40A2 that functions as a flank face and faces the rotation axis AX direction, and a side face that faces the outer diameter direction. 40A3, a side surface 40A4 facing the direction of the base end portion 20B, a side surface 40A5 facing the inner diameter direction, and a bottom surface. Further, a cutting edge is formed at the connecting portion between the end surface 40A1 and the side surface 40A2. Further, the cutting insert 40A is formed with a through hole penetrating its central portion.

  As shown in the figure, the male screw penetrating the through hole is screwed into the female screw formed in the screw hole 22A4, and the head of the male screw presses the end surface of the cutting insert 40A toward the seat surface 22A3. The cutting insert 40A can be attached to the body 20.

  When the cutting insert 40A is attached to the body 20, the side surface 40A4 abuts (or is sufficiently close to) the wall surface 22A1. Further, the side surface 40A5 facing the inner diameter direction contacts (or is sufficiently close to) the wall surface 22A2. In addition, the bottom surface of the cutting insert 40A contacts the seat surface 22A3. Further, since the recess 22A5 and the recess 22A6 are formed, the respective ridge lines that connect the bottom surface of the cutting insert 40A to the side surfaces 40A4 and 40A5 and the surface of the tip seat 22A are opposed to each other. Therefore, it is possible to prevent the ridgeline from being damaged. In the present embodiment, the tip seat 22A further includes a wall portion 22A7. Therefore, the side surface 40A3 of the cutting insert 40A facing the outer diameter direction is supported by the wall portion.

  Further, as shown in FIG. 2, the body 20 is formed with an injection portion 24A for injecting the coolant flowing inside the body 20 toward the side surface and the bottom surface of the cutting insert 40A and bringing them into contact with each other. The ejection portion 24A is formed as an opening hole communicating with the seat surface 22A3 of the tip seat 22A. As shown in this figure, the injection portion 24A has an end surface view seen from a direction facing the seat surface 22A3, and is located in a region where the tip seat 22A exists in the rotation axis AX side (outer diameter direction perpendicular to the rotation axis AX). It is formed on the side of the rotation axis AX from the middle point) and on the side of the base end portion 20B (the area on the side of the base end portion 20B from the middle point of the area where the tip seat 22A exists in the direction of the rotation axis AX). .. Therefore, when the cutting insert 40A is attached, a part of the bottom surface of the cutting insert 40A on the rotation axis AX side and the base end portion 20B side faces the injection portion 24A.

  Further, the injection part 24A or the flow path continuous with the injection part 24A is formed so as to include an intersection where the extensions of the wall surface 22A1, the wall surface 22A2 and the seat surface 22A3 intersect. Therefore, the ejection unit 24A also communicates with the slimes 22A5 and 22A6. When the cutting insert 40A is attached, the recess 22A5 and the recess 22A6 respectively face a part of the two side surfaces 40A4 and 40A5 of the cutting insert 40A while being spaced apart from each other. Therefore, the coolant injected from the injection unit 24A comes into contact with a part of the bottom surface of the cutting insert 40A and a part of the two side surfaces 40A4 and 40A5.

  Further, as shown in the figure, a groove 26A1 and a groove 26A2 communicating with the injection portion 24A are formed in the seat surface 22A3, and further, a groove 26A3 communicating with the groove 26A2 is formed. The groove 26A1 is formed so as to extend from the injection portion 24A in the direction of the rotation axis AX, and communicates with the tip end surface 20A5 (FIG. 1) of the body 20. The groove 26A2 is formed so as to extend in a diagonal direction and communicates with the tip end surface 20A5 of the body 20. Further, since the groove 26A3 is formed so as to be spaced apart from each other substantially parallel to the groove 26A1, the groove 26A3 communicates with the tip end surface 20A5 of the body 20, similarly to the groove 26A1. However, the groove 26A3 and the groove 26A2 are formed via the screw hole 22A4 on the way. In addition, when a groove is further formed and the seat surface 22A3 is viewed from a direction facing the seat surface 22A3, the seat surface 22A3 is divided into four in a direction perpendicular to and parallel to the rotation axis AX (of the seat surface 22A3, the rotation axis AX Divided into four regions by a straight line passing through the midpoint in the direction perpendicular to and parallel to the rotation axis AX, and a straight line passing through the midpoint in the direction parallel to the rotation axis AX and perpendicular to the rotation axis AX). At least one groove may be formed in each region.

  Subsequently, other configurations of the body 20 will be described. As shown in FIG. 1, the outer surface of the tip portion 20A exposed in the outer diameter direction includes an outer surface 20A1 including a curved surface that is a constant arc centered on the rotation axis in a cross section perpendicular to the rotation axis AX. And a second take-up surface 20A2 that is connected to the outer surface 20A1 and that is gradually reduced in distance from the rotation axis AX in a cross section perpendicular to the rotation axis AX and is connected to the wall surface 20A4. Further, when viewed from the tip, the wall surface 20A4 formed in the same direction as the wall surface 22A2 and the end surface 40A1 when the cutting insert 40A is attached so as to connect the wall surface 22A2 and the second cutting surface 20A2. A chip discharge groove 27 is formed from a wall surface 20A3 that is formed so as to extend flush with the base end portion 20B in the direction of rotation of the body 20, and the wall surface 20A3. As shown in the figure, the chip discharge groove 27 is formed so as to be twisted so as to advance in the direction opposite to the rotation direction as it approaches the base end portion 20B.

  On the rear end surface of the body 20 facing the direction opposite to the rotation axis AX, an opening hole including a supply portion 28A for supplying the coolant is formed. Further, a first flow path is formed inside the body 20 so as to connect the supply unit 28A and the injection unit 24A. The first flow path is formed below the wall surface 20A3 by being twisted along the chip discharge groove 27, becomes a flow path perpendicular to the seat surface 22A3 in the vicinity of the injection portion 24A, and is connected to the injection portion 24A. ..

  In addition, a second injection portion 32 formed of an opening hole is formed on the front end surface 20A5 of the body 20. Moreover, the 2nd injection part 32 is open for free passage to the 1st channel by the 3rd channel. Therefore, the coolant supplied from the supply unit 28A passes through the first flow path, part of which is injected from the injection unit 24A in the direction of the seat surface 22A3, and another part of which is supplied from the second injection unit 32 to the rotation axis AX. Jet in the direction.

  Hereinafter, with respect to the tip seat 22B formed at the tip of the body 20 and the cutting insert 40B attached to the tip seat 22B, the same numeral is given to the constituent element exhibiting the same function as the tip seat 22A and the cutting insert 40A. By doing so, detailed description will be simplified and different parts will be mainly described.

  Like the tip seat 22A, the tip seat 22B includes a wall surface 22B1, a wall surface 22B2, a seat surface 22B3, a screw hole 22B4, a recess 22B5, and a recess 22B6. Further, the third ejection portion 24B and the grooves 26B1 and 26B2 are formed. However, as shown in FIG. 3, the grooves 26B1 and 26B2 are different from the grooves 26A1 to 26A3. Specifically, the groove 26B1 communicates with the third injection portion 24B, extends the seat surface 22B3 diagonally through the screw hole 22B4, and communicates with the tip surface 20A5. Further, the groove 26B2 communicates with the screw hole 22B4 and the tip surface 20A5. By thus forming the groove 26B1 connecting the third injection portion 24B and the screw hole 22B4, the coolant can be circulated in an arc shape along the screw groove formed in the screw hole 22B4. It becomes possible to circulate the coolant in the gap between the male screw fixing 40B and the cutting insert 40B. Further, it becomes possible to cause a part of the coolant to flow into the groove 26B2.

  Like the cutting insert 40A, the cutting insert 40B includes an end surface that functions as a rake surface and a side surface that functions as a flank, two side surfaces that respectively abut and face the wall surfaces 22B1 and 22B2 of the tip seat 22B, and a tip seat 22B. A bottom surface that abuts against. However, the cutting edge of the cutting insert 40A functions as a center blade, while the cutting edge of the cutting insert 40B functions as an outer peripheral blade. Therefore, as shown in FIG. 1, the cutting edge of the cutting insert 40A is formed so as to be able to machine the central portion of the hole passing through the rotation axis AX in the end view, while the cutting edge of the cutting insert 40B is formed. It is formed so that the outer peripheral portion and the wall surface of the hole can be machined in end view. Therefore, the tip seat 22A and the tip seat 22B have different shapes, and the seat surfaces 22A3 and 22B3 also have different shapes.

  On the rear end face of the body 20 facing the direction opposite to the rotation axis AX, an opening hole including a second supply portion for supplying the coolant is formed. In addition, a second flow path that connects the second supply unit and the third injection unit 24B is formed inside the body 20. The second flow path is formed below the chip discharge groove corresponding to the cutting insert 40B while advancing in the rotation axis AX direction from the second supply section, and in the second flow path immediately before the third injection section 24B, It is formed perpendicular to the seat surface 22B3.

  Hereinafter, the operation and effect when the work material is processed using the drill 10 configured by attaching the cutting insert 40A and the cutting insert 40B to the body 20 as described above will be described.

  The cutting insert 40A and the cutting insert 40B attached to the body 20 are also attached by connecting the body 20 to a machining center equipped with a rotation driving body (not shown) typified by an electric motor and rotating the body about the rotation axis AX. It can be rotated around the rotation axis AX. Further, by connecting a pump (not shown) for supplying liquid coolant such as water or cutting oil to the supply unit 28A to supply the coolant, the coolant can be circulated in the first flow path inside the body 20. it can. Similarly, the coolant can be circulated in the second flow path of the body 20 by connecting the pump to the second supply unit and supplying the coolant. However, you may make it supply a coolant from a single supply part by branching a 1st supply part and forming a 2nd flow path.

  Part of the coolant that has flowed in the first flow path is injected from the second injection unit 32 through the third flow path that communicates with this. Since the coolant passing through the third flow path substantially advances in the direction of the rotation axis AX, the flow velocity is higher than that of the coolant flowing out of the injection unit 24A. Therefore, chips generated by vigorously injecting the coolant toward the processing surface processed by the cutting edge of the cutting insert 40A can be discharged. Further, since at least a part of the coolant that has collided with the surface of the workpiece goes toward the end face 40A1 direction of the cutting insert 40A, the region of the cutting insert 40 on the end face 40A1 side can be cooled. Further, a part of the coolant that has flowed in the first flow path is ejected from the ejection unit 24A. Here, since the first flow path immediately before the injection portion 24A is formed perpendicularly to the seat surface 22A3, the coolant is injected in a direction substantially perpendicular to the seat surface 22A3 to cool the bottom surface of the cutting insert 40A. Therefore, the cutting insert 40A can be cooled from both the end face 40A1 side exposed to the outside and the bottom face side facing the tip seat 22A.

  Further, since the injection portion 24A communicates with the groove 26A1 and the groove 26A2, a part of the coolant flows into the groove 26A1 and the groove 26A2, and removes heat from the bottom surface of the cutting insert 40A to flow out. Further, since the groove 26A3 communicates with the groove 26A2, the coolant also flows into these. Further, since the injection portion 24A is formed on the rotation axis AX side, it is possible to evenly cool the area of the bottom surface of the cutting insert 40A that requires cooling, by utilizing the centrifugal force. Furthermore, since a part of the coolant flows into the screw hole 22A4, the heat of the cutting insert can be taken from the surface of the screw hole 22A4 facing the male screw fixing the cutting insert 40A. Furthermore, since the injection part 24A is also in communication with the slush 22A5 and the slush 22A6, part of the coolant can also flow into the slush 22A5 and the slush 22A6 to cool the side surfaces 40A4 and 40A5 of the cutting insert 40A. .. An injection portion may be formed on the wall surface 20A4 so that the coolant directly contacts the end surface 40A1 of the cutting insert 40A or the cutting edge so that the coolant advances obliquely.

  After that, the coolant flows into the chip discharge groove 27 from the side surface 40A3 of the cutting insert 40A and is discharged. Since the wall portion 22A7 covers only a part of the side surface 40A3, the coolant can be accelerated to flow into the chip discharge groove 27.

  Similarly, the coolant that has flowed in the second flow path is injected from the third injection portion 24B in a direction substantially perpendicular to the seat surface 22B3, cools the bottom surface of the cutting insert 40B, and then flows into the groove 26B1. The heat is taken from the bottom surface of 40B and flows out. Further, since the groove 26B1 advances in the bearing surface 22B3 in a diagonal direction, the coolant can flow out toward the wall surface of the hole. Therefore, it is possible to assist the discharge of the chips generated by processing the wall surface of the hole with the outer peripheral blade.

  As described above, according to the body 20 and the drill 10 for the cutting edge exchange type cutting tool described above, the cutting insert 40A is cooled from the end face 40A1 side by the coolant discharged from the second injection part 32 opened toward the tip. At the same time, the cutting insert 40A can be cooled from the bottom surface side by the coolant injected from the injection portion 24A on the bottom surface side of the tip seat 22A. By simultaneously cooling the cutting insert 40A from above and below in this way, the cutting insert 40A can be uniformly cooled in a shorter time than ever before.

  In intermittent cutting, when the cutting edge during idling is rapidly cooled by coolant, or when a part of the cutting edge is rapidly cooled, thermal cracking occurs due to thermal shock, which shortens the tool life. There is. However, in the case of the cutting edge replaceable drill according to the present embodiment, since the coolant is also supplied from the injection portion 24A formed on the seat surface 22A3, the side surface 40A4 and the side surface 40A5 of the cutting insert 40A, the bottom surface, and the through hole for penetrating the male screw. The sides can be cooled. Therefore, it is possible to prevent the cooling of only the cutting edge of the cutting insert 40A from being promoted, and to reduce the temperature difference between the cutting edge of the cutting insert 40A and other portions as compared with the conventional case. Therefore, the generation of thermal cracks can be suppressed. The same applies to the cutting insert 40B.

  It should be noted that, instead of forming the grooves 26A1 to 26A3, the coolant is circulated in the respective gaps between the wall surfaces 22A1 and 22A2 of the tip seat 22A and the side surfaces 40A4 and 40A5 of the cutting insert 40A like the recesses 22A5 and 22A6. You can At that time, the injection portion 24A may be formed so as to inject the side surface 40A4 or the side surface 40A5 without injecting the coolant onto the seat surface 22A3.

  Further, the outer shape of the cutting insert and the shape of the cutting insert such as a chip breaker formed on the upper surface thereof are not limited to the present embodiment, and the present invention is applied to cutting inserts for a wide range of drills and other rolling tools. It is possible. Similarly, the wall surface of the tip seat and the like can be deformed according to the outer shape of the cutting insert. Furthermore, the present invention can be applied to other milling tools such as milling cutters and end mills.

10 ... Drill, 20 ... Body, 20A ... Tip, 20A1 ... Outside surface, 20A2 ... Counter surface, 20A3 ... Wall surface, 20A4 ... Wall surface, 20A5 ... Tip surface, 20B ... Base end, 22A ... Tip seat, 22A1 ... wall surface, 22A2 ... wall surface, 22A3 ... seat surface, 22A4 ... hole, 22A5 ... slim, 22A6 ... slim, 22A7 ... wall part, 22B ... chip seat, 22B1 ... wall surface, 22B2 ... wall surface, 22B3 ... seat surface, 22B4 ... screw Hole, 24A ... Injection part, 24B ... Third injection part, 26A1-26A3 ... Groove, 26B1-26B2 ... Groove, 27 ... Chip discharge groove, 28A ... Supply part, 32 ... Second injection part, 40A, 40B ... Cutting Insert, 40A1 ... End face, 40A2-40A5 ... Side face

Claims (7)

A body that rotates around a rotation axis,
In the body,
Tip seat for mounting cutting insert,
A supply unit for supplying coolant from the outside,
A flow path formed inside the body for flowing the coolant supplied from the supply unit;
In order to bring the coolant flowing through the flow path into contact with the second injection portion formed in the body for bringing into contact with the exposed end surface of the cutting insert, and the side surface or the bottom surface of the cutting insert facing the tip seat. And an injection part communicating with the tip seat,
Body for replaceable cutting tools. On the seat surface of the tip seat, which is opposed to the bottom surface of the cutting insert, a groove is formed which communicates with the injection unit and flows the coolant along the bottom surface of the cutting insert.
A cutting edge type cutting tool body according to claim 1. The injection part is formed on the rotation shaft side of the tip seat,
A body for a cutting edge exchange type cutting tool according to claim 2. The tip seat includes a first wall surface facing the tip direction of the body, a second wall surface facing the outer diameter direction of the body, and a seat surface facing the rotation direction of the body and facing the bottom surface of the cutting insert. Equipped with
The injection portion is formed so as to communicate with any of the first wall surface, the second wall surface, and the seat surface.
A body for a cutting edge exchange type cutting tool according to claim 2 or 3. In the body,
A second tip seat for mounting the second cutting insert,
A second supply unit for supplying the coolant from the outside,
A second flow path formed inside the body for flowing the coolant supplied from the second supply part;
A third injection unit is formed that communicates with the second tip seat in order to bring the coolant flowing through the second flow path into contact with a side surface or a bottom surface of the second cutting insert facing the second tip seat,
A second seat surface of the second tip seat, which faces the bottom surface of the second cutting insert, communicates with the third injection unit, and is used for flowing the coolant along the bottom surface of the second cutting insert. 2 grooves are formed,
The groove is formed so as to communicate with the tip end surface of the body,
The second groove is formed so as to communicate with a side surface of the body,
A cutting edge exchangeable cutting tool body according to any one of claims 2 to 4. The flow passage is formed so that the coolant injected from the second injection unit has a velocity component in a direction from the base end to the tip of the body,
The cutting edge exchangeable cutting tool body according to any one of claims 2 to 5, wherein the flow passage is formed so that the coolant injected from the injection unit has a velocity component in the rotational direction of the body. A cutting edge exchangeable cutting tool body according to any one of claims 1 to 6,
An exchangeable cutting tool having the cutting insert.

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