JP2009095967A - Boring tool, cutting blade unit and boring method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform semi-finishing and finishing of a machining hole in a short machining cycle time and with high accuracy without unnecessarily causing the elongation of a tool body and an increase of equipment cost. <P>SOLUTION: A cutting blade 21 for finishing and a cutting blade 11 for semi-finishing arranged by being shifted from the cutting blade 21 in a center line O direction and a peripheral direction of the cylindrical tool body 1 extending along the center line O are provided on an outer peripheral surface of the tool main body 1. Of the cutting blade 11 and the cutting blade 21, one cutting blade is made retracable in the radial direction of the tool body 1. In a projected state of the one cutting blade, the cutting blade is positioned so that a radius from the center line O to the cutting blade 11 may be larger than a radius of the outer peripheral surface and smaller than a radius from the center line O to the cutting blade 21. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an inner diameter machining tool for machining a machining hole (preparation hole) formed in a work material into a predetermined inner diameter, a cutting edge unit used for the inner diameter machining tool, and an inner diameter machining method using the inner diameter machining tool. It is about.

As this kind of inner diameter machining tool, the inventors of the present invention disclosed in Patent Document 1 a plurality of cartridges having a cutting edge portion provided with a cutting edge on the outer periphery of a long cylindrical tool body in the center line direction of the tool body. An adjustment pin that is housed and has a tip that abuts against the back surface of the cutting blade portion, and an adjustment bar that can be advanced and retracted in the axial direction in which a side surface that is inclined to the rear end surface of the adjustment pin is in sliding contact, The line bar provided with the adjustment mechanism which adjusts the position by pressing the said cutting blade part is proposed. Such an inner diameter machining tool has, for example, machining holes adjacent to the cutting edge portions of a plurality of cartridges when a plurality of machining holes having the same inner diameter are formed coaxially at intervals, as in each bearing portion of an engine. After placing the tool body so as to be positioned between the two, the center line of the tool body is arranged coaxially with the axis of the machining hole, and the tool body is rotated around the center line and sent out in the direction of the center line. The blade portion is used for finishing to a predetermined inner diameter by cutting one processing hole.
JP 2006-263829 A

  By the way, prior to finishing with such an inner diameter machining tool, rough machining and intermediate finishing that drives the inner diameter from the rough machining to near the finished machining diameter are performed. Apart from the inner diameter machining tools such as the above-mentioned line bar set to the machining diameter for finishing, a similar inner diameter machining tool with the machining diameter set for intermediate finishing is prepared, and intermediate finishing and finishing machining are prepared. And processing in two steps. However, in recent years, with the demand for shortening the processing cycle time and improving the processing efficiency for such inner diameter processing, it has been required to perform the intermediate finishing and finishing, which were conventionally performed in two steps, in one step. It is coming.

  However, in order to perform such machining for each machining hole of the work material in which a plurality of machining holes having the same inner diameter as described above are provided at intervals, the feed direction of the tool body among the plurality of machining holes Cutting is not possible with the cutting edge for finishing unless the front hole has been semi-finished, and the same number of cutting edges as the machining holes are required for this finishing. It becomes. Therefore, when finishing and finishing are performed in one step, an extremely long tool body in which an inner diameter machining tool for intermediate finishing and an inner diameter machining tool for finishing are integrated coaxially as a result. Therefore, the tool body is likely to be shaken and the processing accuracy may be deteriorated. In addition, the machine tool that holds and rotates and feeds the tool increases in size, resulting in an increase in equipment cost, and the stroke in the feed direction of the tool also increases, so that the machining cycle time can be shortened sufficiently. It becomes difficult.

  The present invention has been made under such a background, and it is possible to perform the above-described mid-finishing and finishing of the hole without increasing the length of the tool body and increasing the equipment cost more than necessary. An object is to provide an inner diameter machining tool that can be performed with high accuracy in a short machining cycle time, a cutting blade unit suitable for the inner diameter machining tool, and an inner diameter machining method using the inner diameter machining tool. Yes.

  In order to solve the above problems and achieve such an object, an inner diameter machining tool of the present invention has a finishing cutting edge and a finishing cutting edge on the outer peripheral surface of a cylindrical tool body extending along a center line. A cutting edge for intermediate finishing arranged so as to be shifted with respect to the cutting edge in the direction of the center line and the circumferential direction of the tool body, and the cutting edge for intermediate finishing and the cutting edge for finishing One cutting edge can be projected and retracted in the radial direction of the tool body, and in a state where the one cutting edge protrudes, a radius from the center line to the intermediate finishing cutting edge is set to be equal to that of the outer peripheral surface. One of the cutting edges is positioned so as to be larger than a radius and smaller than a radius from the center line to the finishing cutting edge.

  Further, the inner diameter machining method of the present invention is an inner diameter machining method for machining the inner diameter of a plurality of machining holes formed coaxially with an interval in a work material using such an inner diameter machining tool, With one of the cutting edges immersed, the center line on the side opposite to the side where the other cutting edge is provided is the center axis of the machining hole. The tool body is supported so as to be eccentric with respect to the tool body, and the tool body is inserted into the machining hole so that the finishing cutting edge and the intermediate finishing cutting blade pass through at least one of the machining holes. The one cutting edge is protruded and positioned, and the center line is supported so as to be coaxial with the center axis, and the tool body is rotated around the center line while the tool body is rotated about the center cutting line. The above-mentioned cutting blade for intermediate finishing is sent to the shifted side, Characterized by processing the side of the inner diameter of the processing hole that is displaced with.

  That is, in the inner diameter machining tool of the present invention, one of the intermediate finishing blade and the finishing cutting blade can be projected and retracted in the radial direction of the tool body. By making the maximum outer diameter of the tool including the other cutting edge out of the intermediate finishing cutting edge and the finishing cutting edge in a state of being smaller than the inner diameter of the machining hole before the intermediate finishing machining, the present invention By supporting the tool body by decentering the center line on the side opposite to the side on which the other cutting edge is provided, as in the inner diameter machining method, the machining hole before machining is finished with the cutting edge for finishing and intermediate finishing. The tool body can be inserted into the machining hole so that the cutting blade can pass therethrough.

  Therefore, by arranging a pair of finishing blades for finishing and finishing blades close to the center line direction of the tool body for each processing hole, processing adjacent to the center axis direction for each processing hole. Since this pair of cutting blades for finishing and finishing can be placed between the holes, one of the cutting blades is then projected and positioned as described above, and the center line of the tool body is machined. The tool main body is supported so as to be coaxial with the center axis of the hole, and further rotated around the center line while the tool main body is shifted to the side where the finishing blade is shifted with respect to the finishing cutting blade in the center line direction. By cutting the machined holes on the shifted side, i.e., the feed direction side, with the finishing blades for finishing in each group, the holes are continuously cut with the finishing blades in the same group to obtain a predetermined inner diameter. Can be finished.

  For this reason, according to the inner diameter machining tool having the above configuration, the intermediate finishing and finishing can be performed continuously, and after inserting the tool body into the machining hole as described above, Since it is only necessary to feed the tool main body by a stroke that the cutting blade for finishing and the cutting blade for finishing cut one machining hole, the machining cycle time can be greatly shortened. In addition, the length of the tool main body can be suppressed to a length obtained by adding the stroke for cutting the one processing hole to the interval between the processing holes at both ends of the work material. It is possible to avoid the lengthening of the tool body, to suppress the deflection of the tool body and to ensure machining accuracy, and to prevent the machine tool from becoming large. Machine tools used for machining and finishing can be used as they are, and increase in equipment cost can be suppressed.

  Here, one of the cutting edges that can be projected and retracted in the radial direction of the tool body may be either the above-described cutting blade for finishing or the finishing cutting blade, but finally determines the inner diameter of the machining hole. It is desirable that the finishing cutting edge to be fixed and fixed to the tool body with high rigidity and high accuracy. Therefore, it is desirable that the one cutting edge is a semi-finishing cutting edge.

  Further, as described above, in order to allow one of the cutting blades to appear and disappear in the radial direction of the tool body, the one cutting blade is detachably attached to a recess opened in the outer peripheral surface of the tool body. Provided in a cutting blade member provided in the unit, the cutting blade member can be positioned on the outer peripheral side in the radial direction of the tool body and urged toward the inner peripheral side in the radial direction so as to protrude and retract in the radial direction. While being attached to the unit and provided with a pressed surface facing the bottom surface side of the recess, the tool body is connected to a pressure fluid supply path for pressing the pressed surface so as to communicate with the bottom surface side of the recess. By forming and pressing the pressed surface with the pressure of the pressure fluid, the one cutting blade is projected to the radial outer peripheral side of the tool body together with the cutting blade member, and this pressure is reduced. , Work the energized cutting edge member It suffices to retract radially inner side of the body.

  In particular, as such a cutting blade unit that is detachably attached to the recess in such an inner diameter machining tool, a cylindrical bush inserted into the recess and a slidably inserted into the bush. The cutting blade member provided with the one cutting blade provided at the front end facing the outer peripheral side of the tool body, and a biasing member that biases the cutting blade member toward the rear end side, and the cutting blade A washer having a contact portion capable of contacting the positioning portion facing the rear end side of the bush at the rear end portion of the member, and a surface facing the rear end side of the washer as the pressed surface The pressure fluid acts on the pressed surface to smoothly project one of the cutting blades together with the cutting blade member, and the contact portion of the washer faces the rear end side of the bush. One of the cutting edges It can be reliably positioned in the radial direction outer peripheral side of the body.

  As described above, according to the inner diameter machining tool and the inner diameter machining method of the present invention, it is possible to continuously perform the finishing and finishing of the machining hole while suppressing the length of the tool body from being increased. Thus, it is possible to shorten the machining cycle time and improve the machining efficiency while preventing the machining accuracy from deteriorating and the equipment cost from increasing. Further, in the cutting blade unit of the present invention used for such an inner diameter machining tool, it is possible to surely and smoothly perform the projection and withdrawal of one of the cutting blades.

  FIGS. 1 to 4 show an embodiment of the inner diameter machining tool of the present invention, and FIGS. 5 to 8 show an embodiment of the cutting blade unit of the present invention used for the inner diameter machining tool of this embodiment. It is shown. As shown in FIG. 1, the inner diameter machining tool of the present embodiment has a multi-stage columnar shape in which the tool body 1 extends along the center line O, and both ends thereof are supported by a machine tool and are shown around the center line O. A plurality of machining holes that are coaxially formed at intervals in a work material (not shown) that are fed in a feeding direction indicated by F while being rotated in a rotation direction indicated by T are processed into a predetermined inner diameter. Go.

  The tool body 1 is provided with a rotation driving unit 1A to which the rotational driving force from the machine tool is transmitted on one end side (right side in FIG. 1) in the center line O direction, and the other end side (from the rotation driving unit 1A) A large-diameter portion 1B whose outer diameter is increased by one step toward the left side in FIG. 1 and a cutting portion 1C having a smaller diameter and a longer length in the center line O direction than the large-diameter portion 1B are provided. And in this cutting part 1C, the cutting edge 11 for finishing which is provided in the cutting blade unit 10 of the said one embodiment as one cutting edge in this embodiment, and the cutting edge for finishing as the other cutting blade in this embodiment A blade 21 is arranged.

  In addition, in this cutting part 1C, the intermediate finishing cutting blade 11 and the finishing cutting blade 21 are shifted one by one to the opposite sides in the circumferential direction, and in the center line O direction for intermediate finishing. A set is made such that the cutting blade 11 is slightly displaced from the finishing cutting blade 21 toward the feed direction F, for example, at a distance smaller than the width in the central axis direction of each processing hole. For example, a plurality of sets (5 sets in the present embodiment) of the same number as the number of processed holes of the work material are arranged so as to be spaced in the direction of the center line O.

  Further, in the circumferential direction of each set, on the same side as the finishing cutting edge 21, in the center line O direction, for example, in the feed direction F side from the intermediate finishing cutting edge 11, for example, the machining hole from the intermediate finishing cutting edge 11. Chamfering cutting blades 31 are provided at intervals slightly larger than the above width. Furthermore, in this embodiment, the finishing edge 11 for finishing, the cutting edge 21 for finishing, and the cutting edge 31 for chamfering are provided also in the outer peripheral part of the end surface by the side of the cutting part 1C of the said large diameter part 1B.

  The cutting portion 1C has a circular cross-section having a central axis C perpendicular to the center line O from the outer peripheral surface to the inner peripheral side in the radial direction with respect to the center line O for each set of the intermediate finishing cutting blades 11. A recess 2 that gradually decreases in diameter as it goes toward the circumferential side is formed in such a manner that the central axis C is parallel to each other in the pair, and the cutting blade unit 10 including the finishing blade 11 for finishing is this recess. 2 and is attached to the tool body 1. More specifically, the recess 2 is reduced in diameter by two steps on the outer peripheral surface side of the cutting portion 1C, and further reduced by one step toward the inner peripheral side so as to slightly exceed the center line O. An annular groove 2A is formed in the inner peripheral surface of the recess 2 in the middle in the radial direction with respect to the center line O of the third step portion. It is connected with the exterior of the tool main body 1 through the hole 2B opened to the outer peripheral surface of 1C.

  Further, in the tool body 1, a pair of pressure fluid supply passages 3 extend from the rotational drive unit 1 </ b> A toward the other end side in parallel to the center line O over the entire length of the tool body 1. And it is drilled so as to sandwich the recess 2 in the radial direction adjacent to the bottom surface of the recess 2. These supply paths 3 are drilled from the outer peripheral surface of the cutting portion 1C so as to pass through one supply path 3 and the bottom of the recess 2 in a direction perpendicular to the central axis C to reach the other supply path 3. Through the communication hole 3A, the bottom surface of the recess 2 is communicated with the annular groove 2A with a gap.

  In the present embodiment, the pressure fluid is a cutting fluid (coolant) that cools and lubricates a cutting portion by the intermediate finishing cutting blade 11 and the finishing cutting blade 21 during cutting, and the pair of supply passages 3 The branch holes 3B are formed toward the intermediate finishing cutting edge 11 and the finishing cutting edge 21, respectively. Further, the opening on the outer peripheral surface side of the communication hole 3A and the opening on the other end side of the tool body 1 are sealed with a plug 3C.

  The cutting blade unit 10 is inserted into the recess 2 formed as described above, and is mounted in the substantially cylindrical bush 12 coaxially with the central axis C, and the central axis C direction in the bush 12 A cutting blade member 13 slidably inserted into the tool body, and an urging force of the cutting blade member 13 toward the radially inner peripheral side (the bottom surface side of the recess 2) of the tool main body 1 on the rear end side in the central axis C direction. It is roughly comprised from the biasing member 14 and the insert 15 for the finishing which is attached to the front-end | tip part of the cutting blade member 13 so that it may face the radial direction outer peripheral side of the tool main body 1, and the said cutting edge 11 for intermediate finishing was formed. Yes.

  The bush 12 integrally has a flange 12A whose diameter is increased by one step on the front end side of the outer peripheral surface, and the rear end side of the flange 12A is the above-mentioned 3 on the radially inner peripheral side of the recess 2. In a state of being inserted into the inner periphery of the step portion, the collar portion 12A is fitted into the second step portion, and the collar portion 12A is locked by the set screw 16 screwed into the bottom surface of the second step portion. Thus, the tool body 1 is fixed. Further, an annular plate-like spacer 17 having an appropriate thickness is interposed between the flange 12A and the bottom surface of the second stage portion of the recess 2 as necessary.

  On the other hand, on the inner peripheral surface of the bush 12, a projecting wall portion 12 </ b> B that protrudes toward the inner peripheral side in the shape of an annular plate centering on the central axis C is formed on the bush 12 in the middle of the central axis C. The bush 12 is formed integrally, and the inner diameter of the bush 12 is made one step smaller than the rear end side at the front end side than the protruding wall portion 12B. In addition, an annular locking groove 12C is formed in the protruding wall portion 12B so that the inner peripheral side of the rear end is cut out in an L-shaped cross section, and the rear end side of the locking groove 12C is A plurality of through-holes 12D penetrating from the facing bottom surface to the wall surface facing the distal end side of the protruding wall portion 12B are formed at intervals in the circumferential direction. Further, the cylindrical portion formed by the bush 12 on the rear end side with respect to the protruding wall portion 12B has a plurality of holes 12E that penetrate the cylindrical portion in the radial direction at equal intervals in the circumferential direction (this embodiment is shown in FIG. 8). These holes 12E are arranged at positions that communicate with the annular groove 2A of the recess 2 in a state where the bush 12 is fitted and fixed in the recess 2 as described above. ing.

  Further, the cylindrical portion formed by the bush 12 on the rear end side from the hole 12E has a pair of parallel planes parallel to the central axis C and parallel to each other and equidistant from the central axis C, and leading edges of these planes. It is formed so as to be cut out by a pair of vertical planes extending on the outer peripheral side on the same plane perpendicular to the central axis C. Then, the pair of flat surfaces facing the rear end side of the bush 12 in the form of arcs of slightly less than ½ formed by being cut out by these vertical planes are in the protruding state of the above-described cutting blade 11 for finishing. The pair of arcuate plate-like portions extending between the positioning portion 12F and the rear end side in parallel with the central axis C are provided between the pair of parallel planes. Is guided in the direction of the central axis C, and is a guide portion 12G that restricts the rotation of the cutting blade member 13 around the central axis C.

  Further, the cutting blade member 13 is composed of a cartridge 18 on the front end side to which the insert 15 for finishing is detachably attached, and a washer 20 attached to the rear end side of the cartridge 18 by a clamp bolt 19 with a head. Has been. Furthermore, the cartridge 18 has a thick disk-shaped barrel portion 18A that is fitted into the cylindrical portion on the distal end side of the protruding wall portion 12B of the bush 12, and the bush portion 12 positioned on the distal end side of the barrel portion 18A. The protruding head portion 18B and a shaft portion 18C extending coaxially with the barrel portion 18A along the central axis C on the rear end side of the barrel portion 18A and inserted through the inner periphery of the protruding wall portion 12B are integrated with each other. It is configured.

  Here, in the present embodiment, the intermediate finishing insert 15 is a substantially square flat plate formed of a hard material such as cemented carbide, and each of the four side ridges of one square surface is cut. A blade is formed, and a mounting hole 15A is formed from the center of the square surface to penetrate the intermediate finishing insert 15 in the thickness direction. Then, the insert 15 for intermediate finishing is directed to the insert mounting seat 18D formed at the tip of the head portion 18B with its thickness direction directed to the central axis C direction, and one of the cutting blades is the one of the above-mentioned cutting edges. The clamp screw 15B, which is seated so as to be positioned at the forefront as the cutting blade 11 for intermediate finishing as a blade, is inserted into the mounting hole 15A and screwed into the head portion 18B, thereby being attached to the cartridge 18, that is, the cutting blade member 13. It is done.

  Further, the surface of the cartridge 18 facing the rear end side of the body portion 18A is formed in a flat shape perpendicular to the central axis C, and this surface of the bush 12 is also formed into a flat shape perpendicular to the central axis C. By abutting against the wall surface facing the tip side of the projecting wall portion 12B, positioning is performed in a state where the cutting blade 11 for intermediate finishing is immersed. Further, the shaft portion 18C extending from the surface facing the rear end side of the trunk portion 18A has a constant outer diameter slightly smaller than the inner diameter of the protruding wall portion 12B, except that the trunk portion 18A side is slightly constricted. However, the rear end surface is formed in a V-shaped cross section that is convex toward the rear end side as shown in FIG. A female screw hole 18E into which the clamp bolt 19 is screwed is formed from the rear end surface toward the front end side to a position that reaches the middle of the body portion 18A along the central axis C.

  Further, the washer 20 protrudes coaxially to a disc-like portion 20A having an outer diameter equal to that of the rear end side portion of the bushing 12A of the bush 12 and a surface facing the front end side of the disc-like portion 20A. The formed cylindrical portion 20B having an outer diameter that can be inserted into the inner peripheral portion on the rear end side of the protruding wall portion 12B of the bush 12, and the inner peripheral side of the cylindrical portion 20B with an interval. A shaft portion 20C having an outer diameter equal to that of the shaft portion 18C is integrally formed.

  Among these, the front end surface of the shaft portion 20C is formed in a concave V-shaped cross section that is in close contact with the convex V formed by the rear end surface of the shaft portion 18C, and from the center of the surface facing the rear end side of the disc-shaped portion 20A. The clamp bolt 19 is inserted through the tip end surface of the shaft portion and a stepped hole 20D for receiving the head portion is passed therethrough. Thus, the unevenness V formed by the front and rear end surfaces of the shaft portions 20C and 18C is formed. The washer 20 is integrated with the cartridge 18 coaxially with the central axis C by screwing the clamp bolt 19 into the female screw hole 18E from the stepped hole 20D.

  Further, on the opposite sides of the washer 20 in the circumferential direction, the outer circumference of the disk-like portion 20A is cut out in the radial direction with respect to the central axis C from the outer circumference of the cylindrical portion 20B, and in the direction of the central axis C. Is a pair of “U” -shaped cross-sections that open to the outer circumference side so as to extend from the disc-shaped portion 20A to the entire length of the cylindrical portion 20B in parallel with the central axis C. Guide grooves 20E are formed, and the guide portions 12G of the bush 12 are fitted into the guide grooves 20E, respectively.

  Accordingly, the guide portion 12G is slidably contacted with these guide grooves 20E, and the outer periphery of the body portion 18B of the cartridge 18 is slidably contacted with the inner periphery on the tip side of the protruding wall portion 12B of the bush 12, whereby the cutting blade member 13 is centered. In a state where the rotation around the axis C is restricted, it is possible to move in and out while sliding in the direction of the central axis C. When the guide portion 12G is fitted in this way, a passage communicating with the inner peripheral portion of the bush 12 between the guide portion 12G and the guide portion 12G is formed on the rear end side of the washer 20. It is left to open.

  Further, the surface of the washer 20 facing the tip side of the disc-shaped portion 20A on the outer peripheral side of the cylindrical portion 20B is a plane perpendicular to the central axis C, which is the contact portion 20F in the present embodiment. . The protruding height of the cylindrical portion 20B from the contact portion 20F to the front end side is made smaller than the depth of the inner peripheral portion of the bush 12 from the positioning portion 12F to the protruding wall portion 12B on the rear end side of the bush 12. When the cutting blade member 13 protrudes toward the distal end side, the abutting portion 20F comes into contact with the positioning portion 12F, whereby the cutting blade member 13 and the intermediate finishing cutting blade 11 are positioned.

  On the other hand, the rear end surface of the disc-shaped portion 20A facing the rear end side of the washer 20 is a pressed surface 20G in the present embodiment. A pair of concave grooves 20H that open to the outer periphery of the disk-shaped portion 20A and extend to the inner peripheral side are formed in the pressed surface 20G in the middle of the pair of guide grooves 20E in the circumferential direction of the washer 20, respectively. These recessed grooves 20H are positioned on opposite sides of the central axis C, and the groove depth gradually decreases toward the inner peripheral side so that the pressed surface 20G of the stepped hole 20D. It is formed so as to be cut off to the pressed surface 20G before reaching the opening.

  Further, the inner diameter of the cylindrical portion 20B of the washer 20 is equal to the inner diameter of the locking groove 12C formed in the protruding wall portion 12B of the bush 12, and the cartridge 18 inserted through the inner periphery of the protruding wall portion 12B. The biasing member 14 is interposed in a cylindrical space defined between the outer periphery of the shaft portion 18C and the locking groove 12C and between the outer periphery of the shaft portion 20C of the washer 20 and the inner periphery of the cylindrical portion 20B. It is disguised. In this embodiment, the biasing member 14 is a coil spring that can be accommodated in such a cylindrical space, and is pressed into the space in a compressed state to press the washer 20, thereby cutting the blade member. 13 is biased to the rear end side, and the cutting blade member 13 biased in this way has a surface facing the rear end side of the body portion 18A of the cartridge 18 as described above, and the tip end of the protruding wall portion 12B of the bush 12 It is positioned in a state in which the cutting blade 11 for intermediate finishing is immersed in contact with the wall surface facing the side.

  The cutting blade unit 10 of the present embodiment configured as described above has a pair of the communication holes that open the pair of concave grooves 20H formed on the pressed surface 20G of the washer 20 at the bottom of the recess 2. 3A is inserted into the recess 2 and attached to the tool body 1 as described above. In the cutting blade unit 10 attached in this manner, the intermediate finishing cutting blade 11 is immersed and positioned as described above without supplying the pressure fluid to the supply passage 3 of the tool body 1. In the embodiment, as shown in FIG. 3, the head portion 18 </ b> B of the cartridge 18 of the cutting blade member 13 is accommodated in the first stage portion of the recess 2 together with the intermediate finishing insert 15, so that the intermediate finishing cutting blade 11 is the cutting portion. The length from the projecting cutting blade 21 and the chamfering cutting blade 31 projecting at this time to the outer peripheral surface of the cutting portion 1C on the opposite side in the diameter direction of the tool body 1 is prevented. That is, the maximum outer diameter of the cutting part 1C is made smaller than the diameter of the processing hole (preparation hole) for performing the inner diameter processing. In this state, a slight gap is provided between the bottom surface of the recess 2 and the pressed surface 20G of the washer 20 facing the bottom surface side.

  On the other hand, when pressure fluid is supplied to the supply path 3 and introduced into the recess 2 from the communication hole 3A, the pressed surface 20G of the washer 20 is pressed by the pressure, whereby the biasing force by the biasing member 14 is applied. Against this, the cutting blade member 13 moves to the distal end side in the central axis C direction, that is, the radial outer peripheral side of the tool body 1, and accordingly, the cutting blade 11 for intermediate finishing changes the rotational direction T as shown in FIG. It projects from the outer peripheral surface of the cutting part 1C so as to face, and is positioned when the contact part 20F contacts the positioning part 12F as described above. However, although the radius from the center line O of the protruding intermediate finishing blade 11 is larger than the radius of the outer peripheral surface of the cutting part 1C, it is larger than the radius of the machining hole (preparation hole) for performing the inner diameter machining. The radius from the center line O to the finishing cutting edge 21 is made smaller.

  In this embodiment, the finishing cutting edge 21 which is the other cutting edge is also formed in the finishing cutting insert 23 which is detachably attached to the cutting portion 1C of the tool body 1 via the cartridge 22. The cartridge 22 can be adjusted in the radial position by an adjusting mechanism having an adjusting pin 24 and an adjusting bar 25 as in Patent Document 1, and the radius of the finishing cutting edge 21 is finely adjusted accordingly. It is possible. Further, the chamfering cutting edge 31 faces the same pair of finishing cutting edges 21 and is arranged in a direction intersecting with the center line O at an angle of 45 °, and does not have such an adjustment mechanism. Except for this, it is formed and attached to the insert in the same manner as the cutting edge 21 for finishing.

  Here, in the circumferential direction of the cutting part 1C, on the side opposite to the recesses 2 of each set, a concave groove 26 having a “U” -shaped cross section that opens to the outer peripheral surface of the cutting part 1C is parallel to the center line O. The cartridge 22 is formed in a substantially rectangular parallelepiped block that fits in the concave groove 26, and is formed on one end side (right side in FIGS. 1 and 2) from the center in the longitudinal direction. The finishing cutting insert 23 is detachably attached to the inserted insert seat 22A. The cartridge 22 has a tool main body on the other end side (left side in FIGS. 1 and 2) from the longitudinal center of the cartridge 22 via a spacer 22B on the groove bottom side of the concave groove 26 as necessary. The clamp screw 22 </ b> C inserted in the radial direction of 1 is screwed into the bottom surface of the concave groove 26 to be fixed in the concave groove 26.

  In the present embodiment, the finishing cutting insert 23 is also formed in a regular triangular flat plate shape from a hard material such as cemented carbide, and one of the regular triangular surfaces is a rake face toward the rotational direction T side. One of the cutting edges formed on the three corners of the equilateral triangular surface is attached as the finishing cutting edge 21 so as to protrude more radially outward than the outer peripheral surface of the cutting part 1C of the tool body 1. It has been. Further, the tool body 1 has an outer peripheral surface that is opened to the concave groove 26 so as to be orthogonal to the position of the insert mounting seat 22A, and a rotational direction T along a tangential line of the outer peripheral surface in a cross section orthogonal to the center line C. A chip pocket 26A extending to the side is formed.

  Further, the tool body 1 has a blind hole 27 having a circular cross section extending between the recess 2 and the groove 26 and extending in a direction perpendicular to a plane including the center line O and the center axis C. The cartridge 22 mounted in the concave groove 26 is formed at a position on one end side in the longitudinal direction (center line O direction) further than the insert mounting seat 22A. After the biasing means 28 such as a spring and the adjusting bar 25 are inserted, an adjusting screw 29 is screwed into the opening of the concave hole 27. The adjustment bar 25 is formed to have an outer diameter that can be fitted into the concave hole 27, and a notch groove having an inclined surface 25 </ b> A that gradually recedes toward the bottom side of the concave hole 27 on the side surface thereof. It is formed to face.

  On the other hand, a mounting hole 22D that penetrates the cartridge 22 in the radial direction of the tool main body 1 is further perpendicular to the concave hole 27 on one end side in the longitudinal direction than the insert mounting seat 22A of the cartridge 22 mounted in the concave groove 26. The tool body 1 extending from the bottom surface of the concave groove 26 to the concave hole 27 is also formed with a through hole communicating with the mounting groove 22D. The adjustment pin 24 is inserted into the attachment hole 22D and the through hole from the attachment hole 22D side, and the tip of the adjustment pin 24 facing the radially inner side of the tool body 1 is formed on the adjustment bar 25. The inclined surface is in close contact with the inclined surface 25A. After the adjustment pin is inserted in this way, a set screw 30 is screwed into the opening on the radially outer side of the tool body 1 of the mounting hole 22D. 24 is brought into contact with the rear end portion.

  Therefore, according to such an adjustment mechanism, the adjustment bar 25 is advanced to the bottom side of the concave hole 27 by screwing the adjustment screw 29 against the urging force of the urging means 28 and is adjusted by the inclined surface 25A. The pin 24 is pushed up to press the cartridge 22 together with the set screw 30 toward the radially outer peripheral side of the tool body 1. As a result, the cartridge 22 is elastically deformed with the portion on the other end side into which the clamp screw 22C is screwed as a fulcrum, and the portion on the one end side in the longitudinal direction is displaced to the outer peripheral side in the radial direction. The cutting edge 21 is also protruded radially outward, and the radius with respect to the center line O is finely adjusted.

  Next, by using such an inner diameter machining tool, a plurality of machining holes (preparation holes) formed coaxially with an interval in the work material are intermediate-finished by the cutting blade 11 for intermediate finishing, An embodiment of the inner diameter machining method of the present invention in the case where the finishing inner blade 21 continuously finishes to a predetermined inner diameter will be described. In the present embodiment, first, the pressure fluid is not supplied to the supply path 3, and the cutting blade member 13 in each pair of cutting blade units 10 is moved to the radially inner peripheral side of the tool body 1 by the biasing force of the biasing member 14. By energizing, the cutting blade 11 for finishing, which is one of the cutting blades that can be projected and retracted, is in a state of being immersed more than the outer peripheral surface of the cutting portion 1C as shown in FIG.

  Next, the tool body 1 is held only on the rotational drive unit 1A side, and the center line O is opposite to the side from which the finishing cutting edge 21 as the other cutting edge protrudes with respect to the center axis of the machining hole. 1, that is, in this embodiment, the recess 2 to which the cutting blade unit 10 is attached is supported so as to be eccentric to the opened side (the lower side in FIGS. 1 and 2), and the cutting portion 1 </ b> C is formed as a machining hole from the other end side. I will go through. Further, the cutting portion 1C is inserted into the machining hole in this way, and each group of the finishing blade 11 for finishing and the cutting blade 21 for finishing are respectively rearward in the feed direction F with respect to the machining hole to be subjected to inner diameter machining. If it passes through each processing hole so that it may be located in the side, it will hold the other end part of cutting part 1C, and will support center line O of tool body 1 so that it may become coaxial with the central axis of a processing hole.

  Then, by supplying the pressure fluid (cutting fluid) to the supply path 3, the cutting blade 11 for finishing is projected and positioned as described above, and the tool body 1 is rotated in the rotation direction T around the center line O. Then, the tool body 1 is sent out in the feed direction F, so that the cutting edge 11 for finishing and the finishing edge 21 protruding from the inner diameter of each processing hole are used for cutting. At this time, the cutting edge 11 for intermediate finishing is shifted to the feed direction F side from the cutting edge 21 for finishing, and the radius from the center line O of the cutting edge 11 for intermediate finishing positioned so as to protrude is the center line. Since the radius is smaller than the radius from O to the finishing cutting edge 21, the machining hole is increased in diameter by the intermediate finishing cutting edge 11 as the tool body 1 is fed, and then the finishing cutting edge 21 is finished. Further, the diameter is further expanded to a predetermined inner diameter.

  Further, in this embodiment, the pressure fluid supplied to the supply path 3 is a cutting fluid, and the cutting fluid passes through the branch hole 3B from the supply path 3 and finishes the intermediate finishing cutting edge 11 and finishes during inner diameter machining. The cutting fluid that is supplied to the cutting site by the cutting blade 21 and that presses the pressed surface 20G of the washer 20 of the cutting blade member 13 in the recess 2 is partially applied to the pressed surface 20G. It flows into the inner peripheral part on the rear end side of the bush 12 from the passage between the groove bottom of the opened guide groove 20E and the guide part 12G, and pushes out the air staying in the inner peripheral part from the hole 12E of the bush 12. It flows into the annular groove 2A of the recess 2 and is ejected to the outer periphery of the cutting part 1C through the hole 2B, and is also supplied to the inner periphery of the machining hole. Further, the chamfering of the opening of the processing hole can be performed by the chamfering cutting blade 31 prior to the inner diameter processing by the intermediate finishing cutting blade 11 and the finishing cutting blade 21.

  When each machining hole is finished to a predetermined inner diameter in this way and each set of finishing cutting blades 21 comes out to the feed hole F side of the machining hole, the rotation of the tool body 1 is stopped and the supply of pressure fluid is performed. Also, the intermediate finishing cutting edge 11 is again immersed in the radially inner peripheral side of the tool body 1 by the urging force of the urging member 14. Note that the pressure fluid remaining between the pressed surface 20G of the cutting blade member 13 protruding at this time and the bottom surface of the recess 2 passes through the inner periphery of the bush 12 from the passage between the guide groove 20E and the guide portion 12G. Therefore, it is possible to smoothly immerse the intermediate finishing cutting blade 11 by retreating the cutting blade member 13. And the holding | maintenance of the other end side of the cutting part 1C is released, and the tool main body 1 is decentered to the opposite side to the finishing cutting edge 21 similarly to the time of insertion, and the finished machining hole, the finishing cutting edge 21 and chamfering are carried out. The tool body 1 is moved in the feed direction F side while avoiding interference with the cutting edge 31, and the cutting portion 1C is pulled out from the machining hole.

  As described above, according to the inner diameter machining tool having the above-described configuration, the intermediate finishing cutting edge 11, which is one of the intermediate finishing cutting edge 11 and the finishing cutting edge 21, appears in the radial direction of the tool body 1. Therefore, the maximum outer diameter of the cutting portion 1C is larger than the inner diameter (diameter) of the machining hole (preparation hole) in a state where the cutting edge 11 for intermediate finishing is immersed in the radially inner peripheral side of the tool body 1. Is set so as to be smaller, the intermediate finishing of the processing hole by the intermediate finishing cutting blade 11 and the finishing processing by the finishing cutting blade 21 are continuously performed for each processing hole as in the above-described inner diameter processing method. Thus, it is possible to carry out only by feeding the tool body 1 once.

  In addition, in the present embodiment, each of the plurality of sets of the intermediate finishing cutting blade 11 and the finishing cutting blade 21 performs processing for each of the plurality of processing holes, and thus substantially one processing hole. The tool body 1 may be sent out by a stroke corresponding to the width in the central axis direction. For this reason, for example, machining cycle time can be significantly reduced compared to finishing with an internal machining tool with only a finishing cutting edge after finishing with an internal machining tool with only an internal cutting edge. As a result, the processing efficiency can be improved.

  Further, as the stroke of the tool body 1 is shortened, the length of the tool body 1 in the center line O direction, particularly in the cutting portion 1C, can be prevented from becoming unnecessarily long. For example, the rigidity of the tool body 1 can be secured and the machining can be ensured as compared with the case where machining is performed with a tool in which an inner diameter machining tool having a finishing blade and an inner diameter machining tool having a finishing cutting blade are connected coaxially. It is possible to suppress runout and improve processing accuracy. Further, it is possible to avoid an increase in the size of a machine tool that supports both ends of the inner diameter machining tool and applies rotational drive and feed. For example, the machine tool used when performing a finishing process and a finishing process in two steps can be used as it is. Since it can be used, an increase in equipment cost can be prevented.

  In particular, while the intermediate finishing cutting edge 11 can be projected and retracted in this way, in this embodiment, the finishing cutting edge 21 which is the other cutting edge is cut to have a predetermined processing diameter via the adjusting mechanism. Since it is fixed to the part 1C, even if there is a variation in the processing accuracy of the finishing cutting edge 11, a processing hole having a predetermined inner diameter can be reliably obtained by the subsequent finishing cutting edge 21. However, in the present embodiment, the intermediate finishing cutting edge 11 can be projected and retracted in the radial direction of the tool body 1 as one cutting edge, and the finishing cutting edge 21 as the other cutting edge is used as the tool body 1. On the contrary, the intermediate finishing cutting blade 11 is fixed to the tool body 1 as the other cutting blade, while the finishing cutting blade 21 is fixed to the cutting blade unit 10 as described above. For example, it may be attached to the tool body 1 so that it can be projected and retracted in the radial direction as one cutting blade. Further, in the present embodiment, the intermediate finishing blade 11 and the finishing cutting blade 21 are shifted so as to be located on the opposite sides in the circumferential direction of the tool body 1, and the width of the machining hole in the center line O direction. Therefore, during the inner diameter machining, the radial cutting load acting on the intermediate finishing cutting blade 11 and the finishing cutting blade 21 acts in a direction that cancels out. Further, it is possible to improve the machining accuracy by suppressing the deflection of the tool body 1.

  In the inner diameter machining tool of the present embodiment, the feed direction F is opposite to the direction toward the other end side in the center line O direction (left side in FIG. 1) in which the cutting portion 1C of the tool body 1 is inserted into the machining hole. In the inner diameter machining method of the present embodiment, the intermediate finishing cutting blade 11 and the finishing cutting blade 21 forming a pair once form a processing hole for performing inner diameter processing in a state where the intermediate finishing cutting blade 11 is immersed. After passing through, the machining hole is cut so that the finishing blade 11 is protruded and pulled back in the feed direction F. On the contrary, the cutting portion is inserted into the machining hole. With the cutting direction as the feed direction, insert the cutting part until the inner finishing edge and finishing edge of each set are positioned in front of the machining hole to be machined inside, then project the intermediate finishing edge as it is. The tool body is sent out in this inserted direction, and the inner diameter is processed. Unishi may be.

  In this case, for example, if there are two machining holes and the inner diameter machining is performed with two sets of the finishing blade for finishing and the cutting blade for finishing, the group on the feed direction side is in a state where the cutting blade for finishing is immersed After passing through the first drilling hole, the cutting edge for finishing will protrude and the next second drilling hole will be machined inside. Therefore, even when machining multiple machining holes, It suffices if the finishing cutting blade and the intermediate finishing cutting blade pass through at least one processing hole. In this case, among the multiple sets of finishing blades and finishing blades, the rearmost set in the feed direction will not pass through the hole before machining the inner diameter. The cutting blade for intermediate finishing will be immersed. In this case, since the feed direction is opposite to that in the above embodiment, the middle finishing cutting blades of each set are also shifted from the finishing cutting blade in the direction of inserting the tool body into the machining hole. Will be.

  In the inner diameter machining tool of the present embodiment, the intermediate finishing cutting blade 11 can be detachably attached to the tool body 1 in order to allow the intermediate finishing cutting blade 11 to be projected and retracted as described above. The cutting blade unit 10 is provided on a freely movable cutting blade member 13, and the cutting blade member 13 is urged and immersed in the radially inner peripheral side of the tool body 1 by a biasing member 14. The pressed surface 20G of the cutting blade member 13 is pressed by the pressure fluid supplied through the supply path 3 of the tool body 1 so as to protrude outward in the radial direction. Therefore, for example, it is not necessary to provide a pressure fluid supply path in another path to immerse the protruding intermediate finishing cutting edge 11, and the structure of the tool body 1 and the supply means of the machine tool for supplying the pressure fluid are simplified. Can be

  In addition, in this embodiment, since the pressure fluid is a cutting fluid, the cutting blade 11 for finishing can be made to appear and disappear by using such a cutting fluid supply means provided on the machine tool side, which reduces the equipment cost. The increase can be prevented more reliably. In addition, in this embodiment, for example, the processing diameter by the cutting blade 11 for intermediate finishing is different in thickness of the spacer 17 interposed between the flange 12A and the recess 2 in the bush 12 of the cutting blade unit 10. It is possible to adjust easily by exchanging them.

  On the other hand, in the cutting blade unit 10 of the present embodiment, the cutting blade member 13 is slidably inserted into a cylindrical bush 12 fitted in the recess 2 so as to be able to protrude and retract in the radial direction of the tool body 1. The cutting blade member 13 is guided at the rear end portion on the radially inner peripheral side with the same outer diameter as the rear end portion inserted into the recess 2 of the bush 12, that is, in the recess 2. A washer 20 having a disk-like portion 20A having an outer diameter that can be fitted without a gap except for the groove 20E is provided, and the pressed surface 20G is a rear end surface of the washer 20. Accordingly, when the pressure fluid is supplied from the supply path 3 to the bottom of the recess 2, the washer 20 acts like a piston in the recess 2, so that the cutting blade member 13 together with the cutting blade member 13 is surely disposed. The tool main body 1 can be protruded to the radially inner peripheral side.

  Further, the washer 20 is formed with the guide groove 20E as described above, while the bush 12 is formed with a guide portion 12G that fits in the guide groove 20E in the direction of the central axis C. When the cutting blade 11 is projected and retracted, the cutting blade member 13 is guided along the guide portion 12G and is reliably projected and retracted in the direction of the central axis C, that is, the radial direction of the tool body 1. The cutting blade member 13 thus projected is restrained from rotating around the central axis C by the guide groove 20E being fitted into the guide portion 12G, and the body portion 18A of the cartridge 18 is Since the contact portion 20F facing the tip side of the washer 20 is brought into contact with the positioning portion 12F of the bush 12 and is positioned while being fitted to the inner peripheral portion on the tip side of the protruding wall portion 12B. The cutting blade member 13 can be held without causing rattling or the like even with respect to a cutting load acting on the finishing cutting blade 11, and stable inner diameter processing can be promoted.

It is a side view which shows one Embodiment of the internal diameter processing tool of this invention. FIG. 3 is an enlarged side view showing a set of cutting blades 11 for finishing and a cutting blade 21 for finishing according to the embodiment shown in FIG. 1. It is XX sectional drawing in FIG. 2 which shows the state where the cutting blade 11 for intermediate finishing shown in FIG. 1 was immersed. It is XX sectional drawing in FIG. 2 which shows the state which the cutting blade 11 for finishing in the embodiment shown in FIG. 1 protruded. It is a partially broken side view which shows one Embodiment of the cutting blade unit 10 of this invention. It is XX partial fracture side view in FIG. It is the top view which looked at embodiment shown in FIG. 5 from the center axis | shaft C direction front end side (radial direction outer peripheral side of the tool main body 1). It is the bottom view which looked at the embodiment shown in Drawing 5 from the central axis C direction rear end side (radial direction inner peripheral side of tool body 1).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tool body 1C Cutting part 2 Recess 3 Pressure fluid supply path 10 Cutting blade unit 11 Cutting blade for intermediate finishing (one cutting blade)
12 Bushing 12F Positioning portion 13 Cutting blade member 14 Energizing member 20 Washer 20F Abutting portion 20G Pressed surface 21 Finishing blade (the other cutting blade)
O Center line of tool body 1 T Rotation direction of tool body 1 F Feed direction of tool body 1 C Center axis of cutting blade unit 10

Claims (5)

  On the outer peripheral surface of the cylindrical tool body extending along the center line, the finishing cutting edge and the center cutting line and the circumferential direction of the tool body are shifted with respect to the finishing cutting edge. A cutting blade for intermediate finishing, and one of the cutting blade for intermediate finishing and the cutting blade for finishing is capable of protruding and retracting in the radial direction of the tool body. In a protruding state, the radius from the center line to the intermediate finishing blade is larger than the radius of the outer peripheral surface and smaller than the radius from the center line to the finishing cutting blade. An inner diameter machining tool characterized in that one of the cutting edges is positioned.   The inner diameter machining tool according to claim 1, wherein the one cutting edge is the intermediate finishing cutting edge.   The one cutting blade is provided on a cutting blade member provided in a cutting blade unit that is detachably attached to a recess opened in the outer peripheral surface of the tool main body, and the cutting blade member is provided on the tool main body. While being positioned on the radially outer peripheral side and being urged toward the radially inner peripheral side and attached to the cutting blade unit so as to be able to project and retract in the radial direction, the surface includes a pressed surface facing the bottom surface side of the recess, 3. The inner diameter machining according to claim 1, wherein the tool body is formed such that a supply path of a pressure fluid that presses the pressed surface communicates with a bottom surface side of the recess. tool.   A cutting blade unit that is detachably attached to the recess in the inner diameter machining tool according to claim 3, and is a cylindrical bush inserted into the recess, and is slidably inserted into the bush. The cutting blade member provided with the one cutting blade at the front end facing the outer peripheral side of the tool body, and a biasing member that biases the cutting blade member toward the rear end side, The rear end portion is provided with a washer having an abutting portion that can come into contact with the positioning portion facing the rear end side of the bush, and the surface facing the rear end side of the washer is the pressed surface. A cutting blade unit characterized by   An inner diameter machining method for machining an inner diameter of a plurality of machining holes formed coaxially with a gap in a work material, using the inner diameter machining tool according to any one of claims 1 to 3. With the one cutting edge immersed, the center line is located on the side opposite to the side where the other cutting edge is provided, of the intermediate finishing cutting edge and the finishing cutting edge. The tool body is supported so as to be eccentric with respect to the central axis, and the tool body is inserted into the machining hole so that the finishing cutting edge and the intermediate finishing cutting blade pass through at least one of the machining holes. Then, the one cutting edge is projected and positioned, and the center line is supported so as to be coaxial with the center axis, and the tool body is rotated around the center line while the finishing cutting is performed. Sends the above-mentioned cutting blade for intermediate finishing to the side shifted from the blade Te, internal machining method characterized by processing the inner diameter of the processing hole of the staggered side.

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