JP2014083629A - Tip replaceable cutting tool and tool body of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tip replaceable cutting tool and its tool body which can improve cutting chip dischargeability while securing rigidity of the tool body and thereby keep machining accuracy stably with high quality and extend the lifetime of the tool.SOLUTION: A cutting edge 21 of a cutting insert 20 extends gradually around an axis line O of the tool body 2 as moving toward the base end side of the tool body 2 in the direction of the axis line O. In a part adjacent to an insert attachment seat 4 in a cutting chip discharge groove 3, concave cutting chip guiding parts 13 are formed. The cutting chip guiding parts 13 have a tip side part 14 corresponding to the insert attachment seat 4 and a base end side part 15 connected to the tip side part 14 and extending to the base end side. At least the tip side part 14 of the cutting chip guiding parts 13 extends along the cutting edge 21.

Description

  The present invention relates to a cutting edge exchangeable cutting tool and a tool body thereof.

  2. Description of the Related Art Conventionally, as shown in, for example, Patent Document 1 below, a blade-tip replaceable cutting tool such as a blade-tip replaceable end mill that performs groove processing, shoulder processing, or the like on a workpiece made of a metal material or the like is known. The cutting edge-replaceable cutting tool has a cylindrical shape and is detachably mounted on a tool body rotated around an axis and a plurality of insert mounting seats formed on the outer periphery of the tool body, and protrudes from the outer periphery of the tool body. A cutting insert having a cutting edge. Further, on the outer periphery of the tool body, a chip discharge groove is formed which gradually extends around the axial line from the tip end along the axial direction toward the base end side, and forms a spiral shape. Are arranged along.

JP 2011-206887 A

However, in the conventional cutting edge exchange type cutting tool, there is room for improvement in enhancing the chip discharging property of chips generated by the cutting process.
Specifically, in the conventional cutting edge-replaceable cutting tool 100 shown in FIGS. 6 to 8, chips generated by cutting the workpiece by the cutting edge 21 of the cutting insert 20 are transferred from the cutting edge 21 to the tool body 101. However, there is a problem that clogging easily occurs in the chip discharge groove 102. If the chips are clogged in the chip discharge groove 102, the processing surface of the work material may be damaged to affect the processing accuracy, or the cutting edge 21 of the cutting insert 20 may be lost to affect the tool life. is there.

  In particular, as shown in FIG. 7, when a positive axial rake angle is given to the cutting edge 21 (outer peripheral edge) of the cutting insert 20, that is, the cutting edge 21 is based on the tip along the axis O direction. When it is gradually inclined toward the rear side (right side in FIG. 7) in the tool rotation direction T toward the end side (upper side in FIG. 7), the sharpness of the cutting edge 21 is enhanced while the chips become longer. It was easy and it was difficult to ensure good chip discharge.

  For the purpose of improving the chip discharge property, for example, it is conceivable to simply form the chip discharge groove 102 to be large and wide. However, in this case, it becomes difficult to secure the thickness of the tool body 101, Stiffness is reduced and core runout or the like is likely to occur, which may affect processing accuracy.

  The present invention has been made in view of such circumstances, it is possible to improve the chip discharge while ensuring the rigidity of the tool body, thereby stably maintaining the processing accuracy in high quality, It is an object of the present invention to provide a cutting edge-exchangeable cutting tool and its tool body capable of extending the tool life.

In order to achieve the above object, the present invention proposes the following means.
That is, the present invention has a columnar shape, a tool main body that is rotated around an axis, and is formed on the outer periphery of the tool main body, and gradually around the axis as it goes from the distal end along the axial direction toward the base end. A chip discharging groove extending in a spiral shape, a plurality of insert mounting seats arranged along the chip discharging groove, and a cutting blade which is detachably mounted on the insert mounting seat and protrudes from the outer periphery of the tool body. A cutting edge exchangeable cutting tool, wherein the cutting edge of the cutting insert gradually extends around the axis line toward the base end side, and the insert mounting in the chip discharge groove A concave chip guide portion is formed in a portion adjacent to the seat, and the chip guide portion is connected to the tip side portion corresponding to the insert mounting seat and the tip side portion. Has a proximal portion extending to the side, and at least the distal portion of the chip guide section, characterized in that it extends along the cutting edge.

In this cutting edge-exchangeable cutting tool, the chips generated by cutting the work material by the cutting edge of the cutting insert flow from the cutting edge to the chip discharge groove, and pass through the chip discharge groove to the base end of the tool body. Discharged to the side.
According to the cutting edge-exchangeable cutting tool of the present invention, the concave chip guide portion is formed in the adjacent portion of the insert mounting seat in the chip discharge groove, and the chip cut by the cutting blade enters the chip guide portion of the chip discharge groove. It has come to flow. Here, the chip guide portion has a front end side portion arranged corresponding to the insert mounting seat, and a base end side portion connected to the base end side of the front end side portion. After flowing into the distal end side portion of the guide portion, it flows into the proximal end side portion.

Since the tip side portion of the chip guide portion extends along the cutting edge, the chips are in sliding contact with the inner surface of the tip side portion substantially uniformly over the entire length in the extending direction of the tip side portion. It can be stably curled into a predetermined shape so as to draw a regular spiral shape and to form a cylindrical shape as a whole. Particularly, when the positive rake angle is given to the cutting edge, the chip shape is more stable. The chip guide portion is formed, for example, in a round groove shape on the inner surface of the chip discharge groove, and the inner diameter of the chip guide portion (the radius of curvature of the inner surface) is smaller than the inner diameter of the chip discharge groove. Accordingly, the outer diameter of the chips curled while being in sliding contact with the inner surface of the guide portion is also reduced.
By curling the chips so as to have the predetermined shape described above, it is easy to control the outflow direction of the chips, the volume of the chips can be kept small, and the increase and decrease in the volume is also suppressed, and the chips are reduced. Emission is stably increased.

As described above, according to the cutting edge replacement type cutting tool of the present invention, by providing a special configuration in which the chip guide portion is formed in the chip discharge groove, for example, the chip discharge groove is simply formed to be large and the rigidity of the tool body is increased. It is possible to improve the chip discharging property without reducing. That is, it is possible to improve the chip discharging property while securing the rigidity of the tool body to prevent the center runout and the like, and the machining accuracy is stably maintained at a high quality.
In addition, since chip discharge is improved and chip clogging is prevented, it is possible to avoid a situation in which the work surface of the work material is damaged or the cutting edge of the cutting insert is lost due to such chip clogging, Therefore, the tool life can be extended while increasing the machining accuracy.

  In the cutting edge exchange type cutting tool of the present invention, the width of the chip guide portion along the axis may be larger at the base end portion than at the tip end portion.

The chips curled into a predetermined shape as described above flow from the tip side portion of the chip guide portion to the base end side portion located on the downstream side in the chip outflow (discharge) direction. Here, as in the configuration of the present invention, the width of the base end side portion of the chip guide portion is made larger than the width of the tip end side portion, so that the chips flowing into the base end side portion are Clogging in the end portion is prevented.
Furthermore, because the width of the base end side portion of the chip guide portion is increased, the chips flowing in the base end side portion are easily discharged toward the chip discharge groove (portion other than the chip guide portion), Chip discharge is more significantly improved.
In the above configuration of the present invention, for example, when the outer diameter of the tool body is small or when the number of the strips of the chip discharge grooves is large, the width of the chip guide portion is ensured to be large together with the circumferential width of the chip discharge grooves. Especially when it is difficult, a remarkable effect is easily obtained.

  Moreover, the cutting edge exchange type cutting tool of this invention WHEREIN: The said chip guide parts adjacent in the said chip discharge groove | channel are good also as arrange | positioning mutually spaced apart.

  In this case, the chips curled into a predetermined shape in each of the chip guide portions are prevented from interfering with each other between the adjacent chip guide portions, and the above-described operational effects are stably achieved.

  Further, in the cutting edge-exchangeable cutting tool of the present invention, the cutting insert has a rake face in which the cutting edge is disposed in an outer peripheral edge portion of the cutting insert in the rotation direction of the axis, and the chip guide is provided. The part may be formed to be continuous with the rake face.

  In this case, the chips cut by the cutting edge flow on the rake face and are easily introduced into the chip guide portion smoothly. Therefore, the above-described effects can be easily obtained more remarkably.

  Moreover, the tool main body which concerns on this invention is used for the blade-tip-exchange-type cutting tool mentioned above.

  According to the tool main body of the present invention, as described above, the tool body is used for a blade-tip-exchangeable cutting tool, and achieves a remarkable effect.

  According to the cutting edge-exchangeable cutting tool and the tool body of the present invention, it is possible to improve the chip discharging property while ensuring the rigidity of the tool body, thereby stably maintaining the machining accuracy at a high quality and the tool life. Can be extended.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing a cutting edge exchangeable cutting tool and a tool body thereof according to an embodiment of the present invention. It is a side view which shows the blade-tip-exchange-type cutting tool which concerns on one Embodiment of this invention, and its tool main body. It is a figure which shows the AA cross section of FIG. It is a figure which shows the BB cross section of FIG. It is a figure which shows CC cross section of FIG. It is a perspective view which shows the conventional blade-tip-exchange-type cutting tool. It is a side view which shows the conventional blade-tip-exchange-type cutting tool. It is a figure which shows the DD cross section of FIG.

Hereinafter, a blade-tip-exchangeable cutting tool 1 according to an embodiment of the present invention will be described with reference to the drawings.
The cutting edge replacement type cutting tool 1 of the present embodiment is detachably mounted on a spindle of a machine tool and rotated about an axis O, thereby cutting a work material made of a metal material or the like such as grooving or shoulder processing. This is an edge mill replaceable end mill that performs machining (rolling machining).

  As shown in FIGS. 1 to 5, the blade-tip-exchangeable cutting tool 1 has a cylindrical shape, is formed on the outer periphery of the tool main body 2 around the axis O, and the axis O direction. The chip discharge groove 3 that gradually extends around the axis O as it goes from the front end along the base to the base end side, forms a spiral, a plurality of insert mounting seats 4 arranged along the chip discharge groove 3, and the insert mounting seat 4 And a cutting insert 20 having a cutting edge 21 that is detachably mounted and protrudes from the outer periphery of the tool body 2.

The tool body 2 is made of a steel material or the like, and has an outer cylindrical shape centered on the axis O. A tool mounting hole 5 extending along the axis O is formed in the tool body 2 so as to penetrate the tool body 2.
A key groove 7 extending from the opening edge of the tool mounting hole 5 toward the radially outer side is formed on the base end surface 6 facing the base end side (upper side in FIG. 2) along the axis O direction in the tool body 2. ing. The tool body 2 is attached to the main shaft by a bolt member inserted into the tool mounting hole 5 with the key groove 7 fitted to a key provided on the main shaft of a machine tool (not shown). While being rotated in the tool rotation direction T, a feed is given in a direction crossing the axis O, and the workpiece is cut.
In the present specification, the opposite side (lower side in FIG. 2) of the machine tool along the axis O direction of the tool body 2 is referred to as the tip side, and the spindle side (in FIG. 2) of the tool body 2. The upper side is called the proximal side. A direction perpendicular to the axis O (direction orthogonal to the axis O) is referred to as a radial direction, and a direction around the axis O is referred to as a circumferential direction. Of the circumferential directions, the direction in which the tool body 2 is rotated around the axis O during cutting is simply referred to as the tool rotation direction T or the front of the tool rotation direction T, and the direction toward the opposite side (reverse tool) Rotation direction) is referred to as the rear of the tool rotation direction T.

  The chip discharge groove 3 is twisted and extended gradually in the circumferential direction from the distal end of the tool body 2 toward the proximal end side. Specifically, a plurality of spiral chip discharge grooves 3 are formed on the outer periphery of the tool body 2 at intervals in the circumferential direction. These chip discharge grooves 3 are opened at the distal end surface of the tool body 2 and gradually extend rearward in the tool rotation direction T toward the proximal end side. In the cutting edge replacement type cutting tool 1 of the present embodiment, three chip discharge grooves 3 are formed in the tool main body 2, that is, the tool main body 2 has three flutes. In the illustrated example, the chip discharge groove 3 is not opened in the base end surface 6 of the tool body 2.

The chip discharge groove 3 has a substantially round groove shape, and a portion of the chip discharge groove 3 other than a chip guide portion 13 described later has a concave curve in a cross section perpendicular to the extending direction.
In addition, a plurality of concave insert mounting seats 4 are formed on a wall surface facing the tool rotation direction T in the chip discharge groove 3, and a cutting insert 20 can be attached to and detached from each of the insert mounting seats 4 by a clamp screw 8. Is attached. The insert mounting seats 4 are arranged along the extending direction of the chip discharge grooves 3 extending in a spiral shape, and in the illustrated example, the insert mounting seats 4 are stepped as a whole.

  The insert mounting seat 4 has a seating surface 9 facing the tool rotation direction T, a mounting surface 10 facing the radially outer side, and a bottom surface 11 facing the proximal end side. The seating surface 9 has a concave V-shaped longitudinal section, and the mounting surface 10 and the bottom surface 11 are each planar. Further, a female screw hole 12 into which the clamp screw 8 is screwed is formed in the mounting surface 10 of the insert mounting seat 4 (see FIG. 5). 1 and 2, the insert mounting seat 4 arranged on the most distal end side of the tool body 2 is not provided with the bottom surface 11, and the cutting insert 20 mounted on the insert mounting seat 4 is not provided. A tip blade 21b, which will be described later, protrudes from the tool body 2 toward the tip side.

  The cutting insert 20 is formed in a polygonal plate shape by a hard sintered body such as cemented carbide. Specifically, the cutting insert 20 has a reverse-inverted symmetrical shape, and a pair of polygonal surfaces 22 facing the thickness direction of the cutting insert 20 and a polygonal surface 22 facing a direction perpendicular to the thickness direction. And a plurality of side surfaces disposed around the periphery of each other. The cutting insert 20 is attached to the insert mounting seat 4 in a state where one of these side faces is a rake face 23 and is directed in the tool rotation direction T. The cutting insert 20 of the present embodiment has a pentagonal plate shape, and the polygonal surface 22 has a pentagonal surface shape. Each side surface has a rectangular surface shape, and the rake surface 23 is a parallelogram surface shape (see FIG. 2).

  In the cutting insert 20, a crossing ridge line between the rake face 23, the polygonal face 22 and the side face continuous with the rake face 23 is a cutting edge 21. As shown in the cutting insert 20 located in the lower right of FIG. 2, when the rake face 23 is viewed from the front, the cutting edge 21 is a straight line formed at the intersecting ridge line of the rake face 23 and the polygonal face 22. A straight tip blade 21b formed at the crossing ridge line of the outer peripheral blade 21a, the rake face 23 and the side face adjacent to the rake face 23, and a convex curve shape that smoothly connects the outer peripheral blade 21a and the tip blade 21b. And a corner blade 21c.

  That is, the cutting edge 21 is disposed on the outer peripheral edge portion of the rake face 23, and a pair of outer peripheral edges 21 a located on the long side of the rake face 23, a pair of tip edges 21 b located on the short side, and a corner part And four corner blades 21c located at the center. Note that the corner blade 21c may not be provided, and in this case, the outer peripheral blade 21a and the tip blade 21b are formed in direct connection.

  The cutting insert 20 is mounted on the insert mounting seat 4 with the outer peripheral edge 21 a of the cutting edge 21 protruding from the outer periphery of the tool body 2. In a state where the cutting insert 20 is mounted on the insert mounting seat 4, the outer peripheral blade 21 a (cutting blade 21) of the cutting insert 20 extends while being inclined toward the circumferential direction gradually toward the proximal end side. In the present embodiment, a positive axial rake angle is given to the outer peripheral blade 21a. Therefore, the outer peripheral blade 21a gradually extends rearward in the tool rotation direction T toward the proximal end side. ing. In the illustrated example, the axial rake angle is about + 10 °.

  Moreover, the cutting insert 20 mounted on the insert mounting seat 4 positioned at the most distal end of the tool body 2 among the plurality of insert mounting seats 4 projects the tip blade 21b of the cutting blade 21 from the distal end of the tool body 2. In this state, it is mounted on the insert mounting seat 4. In a state in which the cutting insert 20 is mounted on the insert mounting seat 4, the tip blade 21 b of the cutting insert 20 extends while being inclined toward the proximal end side gradually toward the radially inner side.

  Of the plurality of side surfaces of the cutting insert 20, a pair of side surfaces facing rearward in the tool rotation direction T are seating surfaces 24 that contact the seating surface 9 of the insert mounting seat 4. The seating surface 24 has a convex V-shaped longitudinal section and can be engaged with the seating surface 9. The seating surface 24 and the seating surface 9 are engaged with each other, whereby the insert mounting seat 4. The rearward movement of the cutting insert 20 with respect to the axis O direction and the tool rotation direction T is restricted.

  Further, in the cutting insert 20 mounted on the insert mounting seat 4, the polygonal surface 22 facing the radially inner side out of the pair of polygonal surfaces 22 is brought into contact with the mounting surface 10 of the insert mounting seat 4. Accordingly, the movement of the cutting insert 20 toward the inner side in the radial direction with respect to the insert mounting seat 4 is restricted. Further, in the present embodiment, in the cutting insert 20 mounted on the insert mounting seat 4, the side surface facing the tip side among the plurality of side surfaces is disposed close to and contacted with the bottom surface 11 of the insert mounting seat 4. However, it may be abutted.

  Further, the cutting insert 20 is provided with an attachment hole 25 that penetrates the cutting insert 20 in the thickness direction. The attachment hole 25 is opened substantially at the center of the pair of polygonal surfaces 22. The clamp screw 8 is inserted into the mounting hole 25 and screwed into the female screw hole 12 of the insert mounting seat 4, whereby the cutting insert 20 is fixed to the insert mounting seat 4.

  As shown in FIG. 2, in the cutting inserts 20 of the plurality of insert mounting seats 4 arranged in one chip discharge groove 3, the rotation trajectories around the axis O of the outer peripheral blades 21 a are the same in the direction of the axis O. These cutting inserts 20 are arranged so as to overlap each other. As a result, one long blade that is continuous in the direction of the axis O is formed on the rotation locus.

And the chip | tip guide part 13 which makes a concave shape is formed in the site | part adjacent to the insert mounting seat 4 in the chip discharge groove | channel 3. FIG. Specifically, the chip guide portion 13 has a round groove shape, and is disposed adjacent to the front of the insert mounting seat 4 in the tool rotation direction T in the chip discharge groove 3.
A plurality of chip guides 13 are formed in the chip discharge groove 3 in correspondence with the plurality of insert mounting seats 4 formed along the chip discharge groove 3. Moreover, the chip | tip guide parts 13 adjacent in the chip discharge groove | channel 3 are arrange | positioned away, without interfering with each other.

  The chip guide portion 13 includes a distal end side portion 14 corresponding to the insert mounting seat 4 and a proximal end portion 15 that extends to the proximal end side and extends to the distal end side portion 14. Of the chip guide portion 13, at least the tip end portion 14 extends along the outer peripheral edge 21 a of the cutting edge 21. Specifically, the distal end side portion 14 of the chip guide portion 13 gradually inclines toward the rear in the tool rotation direction T toward the proximal end side, corresponding to the positive axial rake angle given to the outer peripheral blade 21a. It extends. In the present embodiment, the entire chip guide portion 13 extends along the outer peripheral blade 21a.

The amount of backward displacement (that is, equivalent to the lead angle) in the tool rotation direction T per unit length toward the base end side in the chip guide portion 13 is smaller than the displacement amount (lead angle) of the chip discharge groove 3. It has become.
In FIG. 3, the groove bottom surface facing the radially outer side of the chip guide portion 13 extends so as to be substantially parallel to the axis O of the tool body 2. On the other hand, as described above, the lead angle of the chip guide portion 13 and the lead angle of the chip discharge groove 3 are different from each other, and the chip discharge groove 3 is formed in a concave concave section so that the chip guide portion 13 The height (position in the tool radial direction) of the groove opening edge gradually changes from the distal end side portion 14 to the proximal end side portion 15, and accordingly, the groove depth of the chip guide portion 13 is also increased. From the base end portion 15 to the base end portion 15.

In addition, as shown in FIG. 2, the width along the circumferential direction of the chip guide portion 13 is larger at the proximal end portion 15 than at the distal end portion 14.
Further, in FIG. 1, among the plurality of chip guide portions 13 formed in the chip discharge groove 3, the tip side portion 14 of the chip guide portion 13 positioned at the most tip is opened at the tip surface of the tool body 2. Yes. Further, among the plurality of chip guide portions 13, the tip end portion of the tip end side portion 14 in the chip guide portion 13 other than the chip guide portion 13 positioned at the forefront, and the base of the base end side portion 15 in all the chip guide portions 13. Each end is formed in a concave spherical shape.

  Further, in the illustrated example, the entire length of the chip guide portion 13 (the sum of the length of the distal end side portion 14 and the length of the proximal end portion 15) is the axis of two insert mounting seats 4 adjacent in the chip discharge groove 3. Although it is set to about the sum of the lengths along the O direction, it is not limited to this. In the present embodiment, the entire length of the chip guide portion 13 is set so as to correspond to the length of chips generated by cutting the work material using the cutting edge-exchangeable cutting tool 1.

  Specifically, among the cutting operations using the cutting edge-replaceable cutting tool 1, the processing in which the length of the chip is the longest is grooving, and the length of the chip is an outer peripheral blade protruding from the outer periphery of the tool body 2. The rotation diameter of 21a, the blade length of the outer peripheral blade 21a, and the axial rake angle of the outer peripheral blade 21a can be roughly assumed. In addition, it is more preferable to consider the chip thickness according to the feed per one rotation of the tool. The inventor of the present invention sets the total length of the chip guide portion 13 based on such knowledge and statistics on the lengths of a large number of chip samples actually cut and generated.

  As shown in FIGS. 4 and 5, the chip guide part 13 has a concave curved cross section perpendicular to the extending direction of the chip guide part 13. The inner diameter (the radius of curvature of the inner surface) of the chip guide portion 13 is made smaller than the inner diameter of the chip discharge groove 3 in which the chip guide portion 13 is formed. 4 and 5, the chip guide portion 13 is formed so as to be smoothly continuous with the rake face 23 of the cutting insert 20 mounted on the insert mounting seat 4.

In the cutting edge-exchangeable cutting tool 1 of the present embodiment described above, the chips generated by cutting the workpiece by the cutting edge 21 of the cutting insert 20 flow from the cutting edge 21 to the chip discharge groove 3, and the chips It is discharged to the proximal end side of the tool body 2 through the discharge groove 3.
According to the cutting edge-exchangeable cutting tool 1 of the present embodiment, the concave chip guide portion 13 is formed in the adjacent portion of the insert mounting seat 4 in the chip discharge groove 3, and the chips cut by the cutting blade 21 are discharged as chips. It flows into the chip guide part 13 of the groove 3. Here, the chip guide portion 13 has a distal end side portion 14 arranged corresponding to the insert mounting seat 4 and a proximal end portion 15 connected to the proximal end side of the distal end side portion 14. The chips first flow into the distal end side portion 14 of the chip guide portion 13 and then flow into the proximal end side portion 15.

Since the tip side portion 14 of the chip guide portion 13 extends along the cutting edge 21 (outer peripheral blade 21a), the chips are formed on the inner surface of the tip side portion 14 in the entire length in the direction in which the tip side portion 14 extends. It is stably curled into a clean predetermined shape so as to draw a regular spiral shape and to form a cylindrical shape as a whole while being slid substantially uniformly over the entire surface. In particular, in the present embodiment, a positive axial rake angle is imparted to the outer peripheral blade 21a, so that the chip shape is more stable and the sharpness is sufficiently enhanced. Further, the chip guide portion 13 is formed in a round groove shape on the inner surface of the chip discharge groove 3, and the inner diameter (the radius of curvature of the inner surface) of the chip guide portion 13 is made smaller than the inner diameter of the chip discharge groove 3. Therefore, the outer diameter of the chips slidably brought into contact with the inner surface of the chip guide portion 13 and curled is also reduced.
By curling the chips so as to have such a predetermined shape, it becomes easy to control the outflow direction of the chips, the volume of the chips can be suppressed small, and the increase and decrease of the volume is also suppressed, Chip discharge is stably improved.

As described above, according to the cutting edge-replaceable cutting tool 1 of the present embodiment, the chip discharge groove 3 is simply formed larger, for example, by providing a special configuration in which the chip guide portion 13 is formed in the chip discharge groove 3. Therefore, the chip discharging property can be improved without reducing the rigidity of the tool body 2. That is, it is possible to improve the chip discharging property while securing the rigidity of the tool body 2 to prevent the core runout and the like, and the machining accuracy is stably maintained at a high quality.
Moreover, since chip discharge | emission property is improved and chip clogging is prevented, the situation where the processing surface of a work material is damaged by such chip clogging or the cutting edge 21 of the cutting insert 20 is missing is avoided. Therefore, the tool life can be extended while increasing the machining accuracy.

Moreover, since the width | variety along the circumferential direction of the chip guide part 13 is enlarged in the base end side part 15 rather than the front end side part 14, the following effect is acquired.
That is, the chips curled into a predetermined shape as described above are flowed from the distal end side portion 14 of the chip guide portion 13 to the proximal end portion 15 located downstream in the outflow (discharge) direction of the chips. Go. Here, as in the configuration of the present embodiment, the width of the proximal end side portion 15 of the chip guide portion 13 is larger than the width of the distal end side portion 14, thereby flowing into the proximal end side portion 15. It is possible to prevent chips from becoming clogged in the proximal end portion 15.
Furthermore, the width | variety of the base end side part 15 of the chip guide part 13 is large, and the chip which flows through this base end side part 15 is directed toward the chip discharge groove | channel 3 (site | parts other than the chip guide part 13). It becomes easy to be discharged, and the chip discharging property is more remarkably improved.
In addition, in the said structure of this embodiment, when the outer diameter of the tool main body 2 is small, or when the number of the strips of the chip discharge groove 3 is large, for example, the circumferential width of the chip discharge groove 3 and the chip guide portion 13 In particular, when the width is difficult to ensure, a particularly remarkable effect is easily obtained.

  Further, since the adjacent chip guide portions 13 in the chip discharge groove 3 are arranged apart from each other, the chips curled into a predetermined shape in each of the chip guide portions 13 are adjacent to each other. Thus, it is possible to prevent the interference with each other, and the above-described effects can be stably achieved.

  Further, since the chip guide portion 13 is formed so as to be continuous with the rake face 23 of the cutting insert 20 mounted on the insert mounting seat 4, the chips cut by the cutting edge 21 flow on the rake face 23. It becomes easy to be introduced into the chip guide 13 smoothly. Therefore, the above-described effects can be easily obtained more remarkably.

  Moreover, according to the tool main body 2 of this embodiment, as mentioned above, it is used for the blade-tip-exchange-type cutting tool 1 and achieves a remarkable effect.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

  For example, in the above-described embodiment, the three-flute tool main body 2 in which the three chip discharge grooves 3 are formed has been described. For example, the two-flute tool main body 2 in which the two chip discharge grooves 3 are formed The tool main body 2 having four or more flutes in which four or more chip discharge grooves 3 are formed may be used.

  Moreover, in the above-mentioned embodiment, although the whole chip | tip guide part 13 extended along the outer peripheral blade 21a of the cutting blade 21, it is not limited to this. That is, the chip guide portion 13 only needs to have at least the distal end portion 14 extending along the outer peripheral blade 21a. For example, the proximal end portion 15 extends in a direction different from the extending direction of the outer peripheral blade 21a. It doesn't matter.

  Moreover, although the width | variety along the circumferential direction of the chip guide part 13 was made larger by the base end side part 15 rather than the front end side part 14, it is not limited to this. Specifically, for example, when the outer diameter of the tool body 2 is large or when the number of the strip discharge grooves 3 is small, the width of the chip guide portion 13 is ensured to be large with the circumferential width of the chip discharge grooves 3. If it is easy, the width of the chip guide portion 13 may be equal between the distal end side portion 14 and the proximal end side portion 15, or smaller than the distal end side portion 14 at the proximal end side portion 15. It does not matter.

  Moreover, although the chip | tip guide part 13 made | formed the circular groove shape, it is not limited to this, For example, you may be made into other concave shapes other than a square groove shape or a groove | channel. However, it is preferable that the chip guide portion 13 has the round groove shape described in the above-described embodiment, so that the chip can be curled stably by a predetermined shape.

  In addition, in the range which does not deviate from the meaning of this invention, you may combine each structure (component) demonstrated by the above-mentioned embodiment, a modified example, a note, etc., addition of a structure, omission, substitution, others It can be changed. Further, the present invention is not limited by the above-described embodiments, and is limited only by the scope of the claims.

DESCRIPTION OF SYMBOLS 1 Cutting edge exchange type cutting tool 2 Tool main body 3 Chip discharge groove 4 Insert mounting seat 13 Chip guide part 14 Tip side part 15 Base end side part 20 Cutting insert 21a (21) Peripheral edge (cutting edge)
23 Rake face O Axis T Tool rotation direction

Claims (5)

A tool body that is cylindrical and rotated about its axis;
A chip discharge groove that is formed on the outer periphery of the tool main body and gradually extends around the axis as it goes from the distal end along the axial direction toward the proximal end,
A plurality of insert mounting seats arranged along the chip discharge groove;
A cutting insert having a cutting insert that is detachably mounted on the insert mounting seat and has a cutting edge protruding from the outer periphery of the tool body,
The cutting edge of the cutting insert gradually extends around the axis line toward the base end side,
In a portion adjacent to the insert mounting seat in the chip discharge groove, a chip guide portion having a concave shape is formed,
The chip guide portion has a distal end side portion corresponding to the insert mounting seat, and a proximal end portion extending to the proximal end side connected to the distal end side portion,
At least the tip side portion of the chip guide portion extends along the cutting edge. The cutting edge replacement type cutting tool according to claim 1,
The cutting edge guide cutting tool characterized in that a width along the axis of the chip guide portion is larger at the base end portion than at the tip end portion. The cutting edge replacement type cutting tool according to claim 1 or 2,
The cutting edge exchanging type cutting tool, wherein the chip guide portions adjacent to each other in the chip discharge groove are arranged apart from each other. The cutting edge exchangeable cutting tool according to any one of claims 1 to 3,
The cutting insert has a rake face in which the cutting edge is arranged on the outer peripheral edge portion thereof while facing the tool rotation direction out of the axis.
The cutting edge guide part is formed so as to be continuous with the rake face.   The tool main body used for the blade-tip-exchange-type cutting tool according to any one of claims 1 to 4.

Images