JP2007044846A - Cutting tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cutting tool on which a hard member is easily fastened without causing deformation on a tool main body. <P>SOLUTION: The hard member 10 is fastened on the tool main body 2 by using thermosetting type adhesive resin in the cutting tool 1 constituted by fastening the hard member 10 harder than the tool main body 2 on the tool main body 2 provided with a cutting blade part to cut a cutting object. Additionally, an inner surface of a recessed groove 2c and a side surface of a guide pad are fastened through the adhesive resin by forming the side surface of the guide pad so as to display an inverse taper shape to be engaged with the inner surface of the recessed groove 2c formed on an outer periphery of the tool main body 2 in making the cutting tool 1 as an insert connecting-disconnecting type reamer and making the hard member 10 as the guide pad to hold the axial direction of the tool main body 2 in cutting. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a cutting tool in which a hard member harder than the tool main body is fixed to a tool main body provided with a cutting edge portion that rotates around an axis to cut a workpiece.

  2. Description of the Related Art Conventionally, there is a cutting tool in which a hard member harder than the tool body is fixed to a tool body provided with a cutting edge portion that rotates around an axis to cut a work piece. As this type of cutting tool, for example, there is an insert detachable reamer that finishes a prepared hole formed in a work piece to a predetermined inner diameter with a cutting edge portion detachably provided on the tip side. A plurality of guide pads (hard members) extending along the axis are attached to the outer periphery of the tool main body formed in a substantially columnar shape with the steel material of the insert detachable reamer and the like. This guide pad not only feeds the tool body into the pilot hole, but also makes sliding contact with the inner peripheral surface of the pilot hole finished by the cutting edge, allowing the tool body to be fed straight while maintaining the axial direction of the tool body. Yes.

Such a guide pad is formed of, for example, a cemented carbide that is harder than the tool body or the workpiece, and is generally inserted into a concave groove recessed radially inward on the outer periphery of the tool body and fixed by brazing. ing. Further, at this time, the concave groove is formed such that a pair of opposite side surfaces of the inner surface are along the radial direction of the tool body, that is, the width is constant from the radially inner side to the outer side of the tool body. Also, the guide pad fixed to this is also formed so that both side surfaces are parallel, that is, the width is constant so as to engage with the concave groove (for example, see Patent Document 1).
JP 2002-160125 A

  However, in the cutting tool (insert detachable reamer) as disclosed in Patent Document 1, the hard member (guide pad) is brazed and fixed to the tool body using, for example, silver brazing (brazing material), In this way, when a hard member is fixed to the tool body by brazing, for example, heat of about 620 to 900 ° C. is also applied to the tool body to cause thermal expansion, and after cooling, residual strain is generated and the tool body is There is a problem that deformation such as bending is likely to occur, and it is necessary to correct the bending in a later process.

  In addition, in order to securely fix the hard member by brazing, it is important to control the temperature of the brazing material and the tool body and the time for supplying the brazing material, and particularly the optimum temperature when pouring the brazing material. It is important to maintain a brazing material between the inner surface of the groove and the guide pad in a state where the hard member is inserted into the long groove-like groove formed in the tool body as in Patent Document 1. In the case of pouring all the way from one side of the longitudinal direction to the other, it takes time to braze and it is difficult to maintain the optimum temperature stably during that time. Therefore, the work itself is urgent because it is necessary to complete the brazing work while maintaining the above condition, and there is a problem that a dedicated craftsman worker is required.

  In view of the above circumstances, an object of the present invention is to provide a cutting tool in which a hard member is easily fixed without causing deformation of the tool body.

  In order to achieve the above object, the present invention provides the following means.

  The cutting tool of the present invention is a cutting tool in which a hard member harder than the tool main body is fixed to a tool main body provided with a cutting edge portion for cutting a workpiece, and the hard member is a thermosetting adhesive resin. Is fixed to the tool body.

  Further, in the cutting tool of the present invention, the cutting tool is rotated around an axis by the cutting edge portion detachably provided on the tip side of the tool body formed in a substantially cylindrical shape, and the workpiece An insert detachable reamer that finishes the prepared hole to a predetermined inner diameter, and the hard member is a guide pad that holds the axial direction of the tool body that is fed into the prepared hole while rotating around the axis. It is desirable to be.

  Furthermore, in the cutting tool of the present invention, the outer periphery of the tool main body is formed with a concave groove extending along the axis from the front end side to the rear end side while being recessed radially inward of the tool main body. The concave groove is formed such that the circumferential width gradually increases toward the radially inner side, and the side surface of the guide pad inserted into the concave groove and integrated with the tool body is More preferably, the groove is formed to have a reverse taper shape that engages with the inner surface of the concave groove, and is fixed to the inner surface of the concave groove via the adhesive resin.

  According to the cutting tool of the present invention, since the hard member is fixed to the tool body with the thermosetting adhesive resin, the thermosetting adhesive resin is cured at about 120 to 200 ° C., for example, as described above. For example, compared to brazing (silver brazing) that requires heating at about 620 to 900 ° C., the heating temperature of the tool body can be kept small, and deformation of the tool body can be prevented. In addition, since the heating temperature is low, the heating time is short, and the bonding is completed in a relatively short time, so that the time required for fixing can be shortened.

  In addition, when fixing a hard member with a thermosetting adhesive resin, the adhesive resin does not cure until the hard member is held on the tool body with the adhesive resin interposed and heated. , It is not necessary to quickly perform the work of fixing the hard member, it can be fixed after sufficiently confirming the holding state of the hard member, making the fixing work easy without requiring a dedicated craftsman, And it becomes possible to integrate a tool main body and a hard member reliably.

  Furthermore, in the cutting tool of the present invention, when the cutting tool is an insert detachable reamer and the hard member is a guide pad, the guide pad and the groove of the tool body are provided when the insert detachable reamer is used. The force that pulls the guide pad out of the groove does not act on the fixed part of the tool, that is, the outer surface of the guide pad that faces the outer side in the radial direction of the tool body is pressed against the inner peripheral surface finished by the cutting edge. Because the force acts on the inner side in the radial direction (inner side of the groove), the guide pad does not come off from the tool body even if the fixing strength is not as high as brazing. It is possible.

  Also, when the groove is formed so that the circumferential width gradually increases as it goes radially inward, and the guide pad is formed so that the side surface of the groove has a reverse taper shape that engages the inner surface of the groove. Can reliably prevent the guide pad from slipping out of the concave groove, and even when an adhesive resin having a lower fixing strength than brazing is used, the guide pad can be firmly held by the tool body.

  Hereinafter, a cutting tool according to an embodiment of the present invention will be described with reference to FIGS. 1 to 3. One embodiment of the present invention relates to an insert detachable reamer (cutting tool) that finishes a prepared hole formed in a work piece to a predetermined inner diameter with a cutting edge portion that is detachably provided on the tip side. .

  As shown in FIGS. 1 to 2, the insert detachable reamer 1 according to the present embodiment is detachable by a substantially cylindrical tool body 2 made of steel or the like and a clamp screw 3 on the tip 2 a side of the tool body 2. And a substantially rectangular flat plate-shaped insert (cutting edge portion) 4 made of a hard material such as cemented carbide. The insert detachable reamer 1 is provided with a pilot 5 having a smaller diameter than the outer diameter of the tool body 2 at the tip 2 a of the tool body 2. In the insert detachable reamer 1, a holder 6 connected to a rotating shaft of a machine tool is attached to the rear end 2b of the tool body 2, and the axis O1 is supported by the rotating shaft of the machine tool via the holder 6. The pilot hole formed in the work piece is finished to a predetermined inner diameter with the insert 4 provided on the tip 2a side while being rotated at a high speed. Here, in the present embodiment, the tip 2 a of the tool body 2 indicates the tip portion of the tool body 2 excluding the pilot 5.

  As shown in FIG. 2, the tool body 2 is provided with a tip pocket 8 formed on the outer periphery on the tip 2a side so as to cut out the tool body 2 in a substantially L shape in a cross-sectional view orthogonal to the axis O1. The insert pocket 9 is provided with a wall surface of the tip pocket 8 facing the front side in the rotation direction T of the tool body 2 being recessed one step on the rear side in the rotation direction T of the tool body 2. Further, the insert 4 is mounted on the wall surface 9 a facing the front side in the rotational direction T of the insert mounting seat 9 while bringing one flat surface along the longitudinal direction of the insert 4 into surface contact. At this time, in the insert 4, the cutting edge 4 a formed at the corner portion on the radially outer side on the axis O <b> 1 direction tip 2 a side is positioned slightly radially outside the outer periphery of the tool body 2, and more than the tip 2 a. It is provided so as to be slightly outside the axis O1 direction. The insert 4 thus mounted is provided with a through hole (not shown) that penetrates from the one plane to the other plane located on the opposite side, and the insert 4 is mounted on the tool body 2, A female screw hole (not shown) provided in the wall surface 9a of the insert mounting seat 9 that is in surface contact with the insert 4 is connected to the through hole, and the female screw hole and the clamp screw 3 are fastened while the through hole is inserted. Thus, the insert 4 is detachably integrated with the tool body 2.

  The tool body 2 is provided with a plurality of grooves 2c extending in parallel to the axis O1 from the front end 2a side to the rear end 2b side and recessed from the outer periphery in the radial direction on the outer periphery excluding the insert mounting seat 9. The concave grooves 2c are provided at intervals in the circumferential direction. As shown in FIG. 3, the concave groove 2c has a bottom surface 2d which is a plane perpendicular to the radial direction, and a pair of side surfaces (inner surfaces) 2e whose width increases as the concave groove 2c moves radially inward. It is formed to have an inversely tapered shape so that H1 gradually increases.

  Furthermore, a guide pad (hard member) 10 is inserted into and fixed to the tool body 2 in the concave groove 2c. The guide pad 10 is made of, for example, a cemented carbide that is harder than the tool body 2 or the workpiece, and includes a bottom surface 10a and a pair of side surfaces 10b that engage with the bottom surface 2d and the pair of side surfaces 2e of the groove 2c. It is supposed to be. That is, in the state inserted in the concave groove 2c, the bottom surface 10a is a plane orthogonal to the radial direction of the tool body 2, and the width H2 of the guide pad 10 gradually increases as the pair of side surfaces 10b move radially inward. It is formed so as to exhibit an inversely tapered shape. In addition, an outer surface 10c that is located on the opposite side of the bottom surface 10a and faces radially outward has a circular arc shape with the axis O1 of the tool body 2 as the center, and the outer surface 10c is slightly larger than the outer periphery of the tool body 2. The outer diameter of the outer surface 10c protrudes outward in the radial direction, and is formed to be slightly smaller than the outer diameter of the rotation locus of the cutting edge 4a.

  The concave groove 2c and the guide pad 10 inserted in the concave groove 2c include a bottom surface 2d and a pair of side surfaces 2e of the concave groove 2c, and a bottom surface 10a and a pair of side surfaces 10b of the guide pad 10 engaged therewith. A slight gap H3 of 0.1 mm or less, for example, is provided, and the gap H3 is filled with a thermosetting adhesive resin (for example, one-part epoxy resin adhesive XD911 manufactured by Nagase ChemteX Corporation) 11 Thus, the tool body 2 and the guide pad 10 are integrally fixed.

As described above, the tool body 2 and the guide pad 10 that are integrally fixed by the adhesive resin 11 are prepared at the stage where the tool body 2 in which the groove 2c is formed is prepared, and the bottom surface 2d and the pair of side surfaces 2e of the groove 2c. A predetermined amount of the liquid adhesive resin 11 is applied to the groove, the guide pad 10 is inserted into the concave groove 2c, and the tool body 2 and the guide pad 10 are heated at about 120 ° C. for about 60 minutes. 11 is cured and fixed to each other. Here, since the thermosetting adhesive resin 11 is not cured unless heat of a predetermined temperature or higher is applied, the state in which the adhesive resin 11 is applied to the concave groove 2c or the guide pad 10 is inserted into the concave groove 2c. Even if left in the state, the adhesive resin 11 is not cured. For this reason, the timing of hardening the adhesive resin 11 by heating the tool body 2 and the guide pad 10 by inserting the guide pad 10 into the concave groove 2c can be freely set. Further, when the guide pad 10 is fixed by applying heat of about 120 ° C. to the tool body 2 in this way, for example, compared to brazing (silver brazing) that requires heating of about 620 to 900 ° C., The thermal expansion of the tool body 2 is suppressed to be small, and the distortion of the tool body 2 remaining after cooling hardly occurs. Furthermore, the curing time of this type of thermosetting adhesive resin 11 is different depending on the heating temperature, and it is possible to set the heating temperature so high that residual strain of the tool body 2 does not occur. When heated at about 150 ° C., it can be cured in about 30 minutes. Therefore, it is possible to reduce the tact time for curing the adhesive resin 11 and fixing the guide pad 10 to the tool body 2. Incidentally, the fixing strength (adhesion strength) between the tool body 2 and the guide pad 10 after curing is about 41 N / mm ² .

  Next, a method for finishing the prepared hole formed in the work piece to a predetermined inner diameter using the insert detachable reamer 1 having the above-described configuration will be described.

  The insert detachable reamer 1 is rotated around the axis O1 at a high speed and fed into the prepared hole of the workpiece, whereby the cutting edge 4a of the insert 4 cuts the inner peripheral surface of the prepared hole and finishes to a predetermined inner diameter. From this stage, the outer surface 10c slightly protruding outward in the radial direction of the guide pad 10 provided on the outer periphery of the tool body 2 comes into sliding contact with the finished inner peripheral surface while rotating around the axis O1. Since the guide pad 10 extends on the outer periphery of the tool body 2 so as to be parallel to the axis O1, when the tool body 2 is fed into the pilot hole, the direction of the axis O1 of the tool body 2 is surely aligned with the pilot hole. It is held so as to coincide with the extending direction, and the axis O1 direction is prevented from shifting due to the cutting resistance.

  At this time, a force directed from the outer surface 10c toward the inside in the radial direction of the tool body 2 is applied to the guide pad 10 slidably contacted with the inner peripheral surface finished with the cutting edge 4a, and the tool body 2 is rotated. Along with this, a force in the circumferential direction is applied, but a force that pulls the guide pad 10 out of the concave groove 2c does not act, and even when there is no fixing strength as brazing, it is fixed to the tool body 2 with the adhesive resin 11. It is assumed that the guide pad 10 is not detached from the concave groove 2c. Thereby, the finishing process of a pilot hole will be performed suitably.

  Therefore, according to the insert detachable reamer 1, the guide pad 10 and the tool body 2 are integrated with the adhesive resin 11, and at this time, the guide pad 10 is fixed by applying heat of about 120 ° C. Therefore, the thermal expansion of the tool main body 2 accompanying heating can be suppressed, and the residual strain after cooling can be eliminated. Thereby, it can prevent that the tool main body 2 deform | transforms with a heating, and it is possible to perform highly accurate cutting by processing the workpiece by providing the tool main body 2 which does not produce a deformation | transformation in this way. It becomes.

  Further, by fixing the guide pad 10 integrally with the tool body 2 using the adhesive resin 11, the guide pad 10 can be inserted into the concave groove 2 c coated with the liquid adhesive resin 11, or the tool body 2 and the guide. The timing at which the pad 10 is heated to cure the adhesive resin 11 can be freely set, and the fixing work can be facilitated as compared with the conventional one that is fixed by brazing. Further, since the curing of the adhesive resin 11 does not occur unless heat is applied, the fixing work can be performed with a margin, and the guide pad 10 is fixed to the tool body 2 more accurately without requiring a dedicated craftsman. It becomes possible to make it.

  Further, when the insert detachable reamer 1 is used for cutting, a force that causes the guide pad 10 to come out of the concave groove 2c does not act on the fixed portion between the guide pad 10 and the concave groove 2c of the tool body 2. Even if there is no strength, the guide pad 10 is not detached from the tool body 2, and it is possible to sufficiently cope with resin bonding.

  Further, at this time, the concave groove 2c is formed so that the circumferential width H1 gradually increases toward the inner side in the radial direction, and the reverse tapered shape in which the side surface 10b of the guide pad 10 is engaged with the side surface 2e of the concave groove 2c. The guide pad 10 can be reliably prevented from coming out even if a force that causes the guide pad 10 to come out of the concave groove 2c is applied. Can be firmly held by the tool body 2.

  In addition, this invention is not limited to said one Embodiment, In the range which does not deviate from the meaning, it can change suitably. For example, in the present embodiment, the cutting tool is the insert detachable reamer 1 and the hard member is the guide pad 10. However, for example, a brazing tool in which a cutting blade member is brazed or a tool body In addition to a reamer, the cutting tool may be a drilling tool such as a drill or a boring bar, or a cutting tool such as a bite provided with the hard member 10 as a reinforcing member. . Further, the hard member 10 may be cermet or the like in addition to the cemented carbide.

  In the present embodiment, the thermosetting adhesive resin 11 is a one-component epoxy resin adhesive and has been described as being cured by applying heat of about 120 ° C. In the case of using and fixing, since it has a great effect that the timing of fixing can be freely set as compared with the case of fixing by brazing, it is larger than the adhesive resin 11 shown in the present embodiment. It may be an adhesive resin that cures at a heating temperature, or may be a resin other than a one-component epoxy resin.

It is a side view of the cutting tool concerning one embodiment of the present invention. It is an AA arrow line view of FIG. It is an enlarged view of the adhering part of the hard member and tool main body of FIG.

Explanation of symbols

1 Insert detachable reamer (cutting tool)
2 Tool body 2a Front end 2b Rear end 2c Groove 2d Bottom surface 2e Side surface (inner surface)
4 Insert (cutting edge)
4a Cutting blade 10 Guide pad (hard member)
10a Bottom 10b Side 10c Outer surface H1 Groove width H2 Guide pad width H3 Gap between groove and guide pad (adhesive resin thickness)
T rotation direction O1 axis

Claims (3)

In a cutting tool in which a hard member harder than the tool body is fixed to a tool body provided with a cutting edge part for cutting a work,
A cutting tool, wherein the hard member is fixed to the tool body by a thermosetting adhesive resin. The cutting tool according to claim 1,
A cutting tool is rotated about an axis by a cutting edge portion detachably provided on the tip side of the tool body formed in a substantially cylindrical shape, and a prepared inner diameter is formed in the work piece. A cutting tool characterized in that the hard member is a guide pad that holds the axial direction of the tool body fed into the prepared hole while rotating around the axis. The cutting tool according to claim 2, wherein
On the outer periphery of the tool main body, a concave groove extending along the axis from the front end side to the rear end side while being recessed radially inward of the tool main body is formed, and the concave groove is formed on the radially inner side. The guide pad, which is formed so that the circumferential width gradually increases as it goes to, and is integrated with the tool body by being inserted into the concave groove, has a side surface engaged with the inner surface of the concave groove. A cutting tool, which is formed to have a tapered shape and is fixed to an inner surface of the concave groove via the adhesive resin.

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