JP2019042882A - cutter - Google Patents

Abstract

To provide a cutter, which allows a main body thereof to be mounted on an arbor surely even if the cutter is a blade edge replaceable cutter with a small diameter, without increasing the number of components and causing complication of a manufacturing step.SOLUTION: A cutting blade 6a is arranged at an outer periphery of a tip part of a cutter main body 1 that is rotated around a shaft line O, and a mounting hole 7 which penetrates through the cutter main body 1 along the shaft line O is formed at the center part of the cutter main body 1. The mounting hole 7 comprises an opening part 7a which opens to a tip of the cutter main body 1, a storage part 7b, formed near a rear end of the opening part 7a, which can store a head part 12a of a bolt 12 with the head part, and a female screw part 7c having a screw cut off at an inner periphery part thereof. The female screw part 7c is mounted with a mounting member 18 having at an outer periphery part thereof a male screw part 18c that can be screwed into the female screw part 7c. In the mounting member 18 is formed a through-hole 18g with an inner diameter smaller than the head part 12a, through which the screw part 12c of the bolt 12 with the head part can be inserted with the head part 12a stored in the storage part 7b.SELECTED DRAWING: Figure 12

Description

  BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a cutter in which a cutting blade is disposed on an outer periphery of a tip end portion of a cutter main body which is rotated about an axis.

  Conventionally, in order to attach such a cutter to an arbor, a bolt with a head (set bolt) is inserted through a through hole formed along the axis of the cutter body, and a screw hole formed at the tip of the arbor Although it is common to screw in and attach, in this case, it is necessary to form a counterbore at the tip of the cutter body to accommodate the head of the headed bolt, especially in the case of an indexable cutter etc. Since this counterbore interferes with the insert mounting seat, it has been difficult to cope with the reduction in diameter of the cutter.

  Therefore, for example, Patent Document 1 includes a cutter main body fitted with an axial center at the tip of a tool mounting shaft (arber) and a screw rod for directly fixing the cutter main body to the tool mounting shaft. The threaded rod has an annular relief groove formed at the central portion in the longitudinal direction, and has a first external thread formed on one end side to be screwed into a threaded hole provided on the tip end face of the tool mounting shaft. On the other end side of the second male screw, a second male screw of reverse thread with almost the same diameter as the first male screw is formed, and in the cutter body, a cutter with a screw hole screwed to the second male screw of a screw rod is proposed ing.

  Further, in Patent Document 2, a cutting insert is detachably attached to an outer peripheral portion of an axial tip end side of a tool main body rotated about an axial center line, and an axial rear end side of the tool main body is arbored by a mounting bolt. In the indexable cutting tool attached to the tool, using the mounting bolt provided with a tightening hole in the bolt head, use the bolt head of the mounting bolt at the center of the tool rear end in the axial direction A guide receiving hole for guiding and receiving from the rear end side of the direction is provided, and a holding means for holding the mounting bolt received in the guide receiving hole rotatably in the guide receiving hole is provided. A tightening hole smaller in diameter than the bolt head is provided so as to penetrate from the tip end side in the axial direction of the tool body to the above-mentioned guide accommodation hole, and the above-mentioned mounting bolt is held by the holding means When holding in the inner accommodation hole, a through hole is provided at the center of a noncircular circular member to be placed on the bolt head of the mounting bolt accommodated in the guide accommodation hole, and the insertion hole is attached The bolt shaft of the bolt is inserted to accommodate the non-circular clamp member in the guide accommodation hole, and the clamp member is rotated to engage the clamp member in the locking portion provided in the guide accommodation hole. Furthermore, a cutter is provided which accommodates a rotation suppressing member for stopping the rotation of the clamp member locked to the locking portion in the guide housing hole and fixes the rotation suppression member in the guide housing hole by the screw member. Proposed.

Patent No. 2503842 Patent No. 5307619

  In the cutter described in Patent Document 1, there is no need for the screw rod to have a head, and therefore, it is not necessary to form a counterbore for housing the head at the tip of the cutter body. However, there is no interference with the insert mounting seat. However, in the cutter described in this patent document 1, the second male thread of the screw rod and the screw hole of the cutter body for pressing and fastening the cutter body to the arbor have substantially the same diameter as the screw holes of the first male screw and the arbor. Since it is at a position close to the axis of the cutter main body, it is difficult to secure a large pressing force, and there is a problem that the cutter is easily loosened.

  On the other hand, in the cutter described in Patent Document 2, in order to attach the cutter main body to the arbor, four kinds of parts, a mounting bolt, a clamp member as a holding means, a rotation restraining member, and a screw member are required, And it is easy to lose parts. In addition, in order to provide the locking portion in the guide receiving hole, it is necessary to carry out milling or the like, which complicates the manufacturing process of the cutter body, resulting in inefficiency and uneconomical.

  The present invention has been made under such a background, and it is an index changeable type with a small diameter without increasing the number of parts required to attach the cutter body to the arbor and without complicating the manufacturing process of the cutter body. An object of the present invention is to provide a cutter which can securely attach a cutter body to an arbor even if the cutter is a cutter.

  In order to solve the above problems and to achieve such an object, according to the present invention, a cutting blade is disposed on the outer periphery of a tip end portion of a cutter main body rotated about an axis, and a central portion of the cutter main body A mounting hole is formed along the axis and penetrates the cutter body, and the mounting hole is formed at the rear end side of the opening with an opening at the tip of the cutter body and a head A housing portion capable of housing the head of the bolt with a portion, and a female screw portion having a thread formed on the inner peripheral portion, and the female screw portion has an outer periphery of a male screw portion that can be screwed into the female screw portion. A mounting member having a head portion is mounted, and the threaded portion of the headed bolt can be inserted through the mounting member in a state where the head portion is housed in the housing portion, and the penetration of the inner diameter smaller than the head portion It is characterized in that a hole is formed.

  In the cutter having such a configuration, an engagement recess is formed in the head of the headed bolt (set bolt) to engage with a working tool such as a shaft-like hexagonal wrench, thereby making it possible to The headed bolt can be rotated by the operation of (1), and the headed bolt thus rotated is screwed into the screw hole formed at the tip of the arbor and the head via the mounting member. The cutter body is pressed against the tip of the arbor and fixed.

  Therefore, it is only necessary to form an opening having a diameter smaller than that of the accommodating portion for accommodating the head of the headed bolt at the tip of the cutter body, and the insert mounting seat and the mounting hole interfere with each other Can avoid doing so. In addition, since the minimum number of parts required to attach the cutter body to the arbor is only two, that is, the head bolt and the attachment member, complicated parts management can be avoided, and the cutter body Also, since the mounting members need only be formed on the female screw portion, the manufacturing process of the cutter body is not complicated.

  And in the cutter of the above-mentioned composition, a head larger diameter than a screw part of a headed bolt presses a cutter main part to a tip part of arbor via an attachment member as mentioned above. That is, since the screw body and the head larger in diameter than the screw hole of the arbor into which the screw body is screwed press the cutter body via the mounting member at a position away from the axis of the cutter body, a large pressing force is secured As a result, it is possible to prevent the bolt with the head from being loosened, and it becomes possible to securely fix and attach the cutter body to the arbor.

  Here, even if it is possible to prevent loosening of the headed bolt in this way, the headed bolt causes loosening between the male screw of the mounting member for pressing the cutter body and the female screw of the mounting hole. As a result, the cutter body can not be attached to the arbor securely. Therefore, in order to prevent such looseness of the mounting member, a flat portion parallel to the axis is formed in the mounting member, and a locking screw capable of abutting on the flat portion is screwed into the cutter main body. Thus, it is desirable to restrain the rotation of the mounting member.

  Further, the mounting member is accommodated in the mounting hole as a whole, and the mounting hole on the rear end side of the mounting member is inserted into the distal end convex portion provided at the distal end portion of the arbor In the case of a part, the overall length of the cutter main body in the axial direction can be shortened, and in the case of a cutter having a small diameter in particular, high rigidity can be secured, and also the attachment strength with the arbor can be improved. High processing accuracy can be obtained.

  In this case, the female screw portion of the mounting hole and the male screw portion of the mounting member are made to have a screw pitch smaller than the screw pitch of the screw portion of the headed bolt or the screw of the headed bolt By twisting in the opposite direction to the part, it is possible to more reliably prevent the attachment member from being loosened by the rotation of the headed bolt when attaching the cutter body to the arbor.

  On the other hand, the rear end outer peripheral portion of the mounting member is formed in the shape of a flange that overhangs the rear end surface of the cutter main body, and is exposed to the outside from between the rear end surface and the tip end surface of the arbor It is also good. In this case, the male screw portion is formed on the outer peripheral side of the insertion portion as an insertion portion in which the rear end inner peripheral portion of the attachment member is communicated with the through hole and the tip end convex portion of the arbor is inserted. For example, the male screw portion and the female screw portion of the mounting hole into which the male screw portion is screwed can be made large in diameter, and the mounting member can be mounted more stably.

  Further, in this case, the female screw portion of the mounting hole and the male screw portion of the mounting member are twisted in the same direction as the rotation direction of the cutter main body at the time of cutting as it goes to the rear end side in the axial direction. By doing this, the cutting load acts in the direction opposite to the rotation direction of the cutter body at the time of cutting on the mounting member in which the flange-like rear end outer peripheral portion is sandwiched between the rear end face of the cutter body and the tip end face of the arbor Even in this case, the mounting member can be prevented from being loosened.

  As described above, according to the present invention, it is a blade exchange type cutter having a small diameter without increasing the number of parts required to attach the cutter body or complicating the manufacturing process of the cutter body. Also, the cutter body can be securely attached to the arbor.

1 is a perspective view of a first embodiment of the invention attached to the tip of an arbor. FIG. 2 is a side view of the embodiment shown in FIG. 1 (although the cutting insert is not shown). It is ZZ sectional drawing in FIG. 2 (however, cutting insert is abbreviate | omitted). It is ZZ sectional drawing in FIG. 3 (however, cutting insert is abbreviate | omitted). It is a perspective view of the cutter main body of embodiment shown in FIG. It is a top view of the rear end surface of the cutter main body shown in FIG. FIG. 7 is a side view in the direction of the arrow X in FIG. FIG. 7 is a cross-sectional view taken along the line YY in FIG. It is ZZ sectional drawing in FIG. (A) top view of the attachment member of the embodiment shown in FIG. 1, (b) side view in the direction of arrow X in (a), (c) side view in the direction of arrow Y in (a) is there. FIG. 7 is a perspective view of a second embodiment of the invention attached to the tip of the arbor. FIG. 12 is a side cross-sectional view of the embodiment shown in FIG. It is ZZ sectional drawing in FIG. It is a perspective view of the cutter main body of embodiment shown in FIG. It is a bottom view of the front end surface of the cutter main body shown in FIG. It is a top view of the rear end surface of the cutter main body shown in FIG. FIG. 17 is a side view in the direction of the arrow Y in FIG. 16. FIG. 17 is a ZZ sectional view in FIG. (A) a perspective view, (b) a plan view, (c) a bottom view, (d) a side view of the attachment member of the embodiment shown in FIG. It is a side view in the arrow Y direction seen in b).

  1 to 10 show a first embodiment of the present invention. The cutter main body 1 in the present embodiment is formed of a metal material such as steel material in a substantially cylindrical shape in which the central portion in the direction of the axis O is constricted about the axis O. The tip portion of the cutter main body 1 (FIG. In the lower part, the cutting blade 2 is used, and the rear end is the mounting part 3 attached to the arbor 11. Such a cutter is fed out in a direction intersecting the axis O while being rotated about the axis O in the cutter rotational direction T by holding the arbor 11 attached to the mounting portion 3 on the spindle of the machine tool. A cutting material is cut by a cutting blade disposed in the cutting blade portion 2.

  The end of the arbor 11 is formed in a cylindrical shape, except that a small-diameter cylindrical end convex portion 11a coaxial with the cylinder formed by the arbor 11 is formed at the central portion of the end surface. A screw hole 11b into which a headed bolt 12 for attaching the cutter main body 1 to the arbor 11 is screwed is formed in 11a, and is opened at the center of the tip surface of the tip convex portion 11a. Further, on the tip end surface of the arbor 11, a pair of keys 11c extending on the outer peripheral side in the diameter direction is formed at a slight distance from the outer periphery of the tip protrusion 11a.

  On the outer periphery of the tip end portion of the cutter body 1, a plurality of (four in this embodiment) tip pockets 4 extending from the tip end of the cutting edge 2 toward the rear end are formed circumferentially. Insert mounting seats 5 are respectively formed on the tip outer peripheral portions of wall surfaces of these chip pockets 4 facing the cutter rotational direction T, and cutting inserts 6 having cutting edges 6a on these insert mounting seats 5 can be removed by clamp screws 6b Attached to That is, the cutter of the present embodiment is a blade-tip-replaceable cutter in which the cutting edge 6 a disposed on the outer periphery of the tip end portion of the cutter main body 1 is formed on the cutting insert 6.

  On the other hand, in the inside of the cutter main body 1, an attachment hole 7 penetrating the cutter main body 1 along the axis O is formed at the central portion of the cutter main body 1. The mounting hole 7 is an opening 7a opened at the tip of the cutter body 1, and a housing 7b formed on the rear end side of the opening 7a and capable of housing the head 12a of the headed bolt 12; And a female screw 7c having a threaded portion at its inner periphery. The head portion 12a of the headed bolt 12 is formed in a disk shape, and an engagement concave portion 12b such as a regular hexagonal cross section engaged with a work tool such as a shaft-like hexagonal wrench is formed on the tip end surface. ing.

  In the present embodiment, the opening 7a and the housing 7b are circular in cross section, and the inner diameter (diameter) of the opening 7a is smaller than that of the housing 7b, and the diameter of the opening 7a is axial. It is sized so that the tool can be inserted, that is, slightly larger than the diameter of the circumscribed circle of the engagement recess 12b of the headed bolt 12 and smaller than the outer diameter of the head 12a. Further, the inside diameter of the housing portion 7b is set such that the tip end on the opening 7a side can be loosely fitted with the head 12a, and the diameter is increased by one step from the tip end toward the rear end side. And then gradually reduce in diameter to reach the internal thread 7c.

  Furthermore, the inner diameter of the female screw 7c is sized to allow the head 12a of the headed bolt 12 to pass through, that is, slightly larger than the inner diameter of the tip of the housing 7b. Further, on the rear end side with respect to the female screw 7c, the mounting hole 7 is expanded one step in diameter in the same manner as the housing portion 7b, and then extends to the rear end side with a constant inner diameter. And the rear end face of the cutter body 1 is opened. A portion of a fixed inner diameter of the mounting hole 7 opened at the rear end face is made an insertion portion 7d which is fit into the tip convex portion 11a of the arbor 11 and is insertable.

  Then, the mounting member 8 as shown in FIG. 10 is screwed and attached to the female screw portion 7 c in a state where the head portion 12 a of the head bolt 12 is accommodated in the accommodation portion 7 b. The mounting member 8 is formed in an annular shape of a metal material such as steel as in the cutter main body 1, and its front end (the lower portion in FIGS. 10 (b) and (c)) is a rear end (FIG. 10 (b)). In (c) and (c), the outer diameter is slightly larger than that of the upper portion), and an external thread 8a to be screwed into the internal thread 7c is formed on the outer periphery of the tip.

  Further, as described above, in the state where the head portion 12a is housed in the housing portion 7b as described above, the screw portion 12c of the headed bolt 12 can be inserted and the inner diameter is smaller than the head portion 12a. Through hole 8b. The internal thread 7c of the mounting hole 7 and the external thread 8a of the mounting member 8 have a thread pitch smaller than the thread pitch of the thread 12c of the bolt 12 with a head, or the direction of twist is with a head The opposite direction to the screw portion 12 c of the bolt 12 is taken.

  Furthermore, on the outer periphery of the rear end portion of the mounting member 8 which is slightly smaller in diameter, a pair of flat portions 8c are parallel to each other and parallel to the axis O in a state where the mounting member 8 is mounted on the cutter body 1 It is formed. Furthermore, when the mounting member 8 is mounted on the cutter main body 1 by screwing the male screw 8a into the female screw 7c at the rear end of the mounting member 8, the mounting jig 8 is not shown. A pair of holes 8d into which the front end portions of the letter shaft are inserted are formed in a diameter direction passing through the axis O in parallel to the plane portion 8c with the through holes 8b seen from the rear end side , And the rear end surface of the mounting member 8 is opened.

  Such a mounting member 8 is inserted into the through hole 8b while inserting the screw portion 12c of the headed bolt 12 in a state where the head 12a of the headed bolt 12 is accommodated in the housing portion 7b of the mounting hole 7. It is disposed immediately above the female screw 7c. Furthermore, the male screw 8a is screwed into the female screw 7c by inserting the U-shaped shaft of the mounting jig into the hole 8d and rotating it around the axis O as described above. It is attached. Therefore, the mounting member 8 in the present embodiment is entirely housed in the mounting hole 7.

  The cutter main body 1 has two pairs of screw holes 1a extending in a direction perpendicular to the pair of flat portions 8c at the rear end of the mounting member 8 in a state where the mounting member 8 is thus attached to the female screw 7c. , And are formed at equal intervals with the axis O with the axis O in between, and an imo-screw-shaped locking screw 9 capable of abutting on the flat portion 8c is screwed into these screw holes 1a from the outer peripheral side ing. Further, in the rear end face of the attachment part 3 of the cutter main body 1, a pair of the tip 11a of the arbor 11 can be fitted with the key 11c in a state where the tip convex part 11a is inserted into the insertion part 7d of the attachment hole 7 and inserted. The key groove 1b is formed.

  Furthermore, a hole (not shown) is formed along the axis O from the rear end of the threaded portion 12c of the bolt 12 with a head, and this hole branches off halfway and the tip convex portion of the arbor 11 in the mounting hole 7 An opening is made in a space C formed between the front end surface 11 a and the rear end surface of the mounting member 8. On the other hand, a coolant hole 1 c extending from the space C to the outer periphery of the tip of the cutter body 1 and opened in the chip pocket 4 is formed in the cutter body 1, and the hole of the headed bolt 12 from the arbor 11 is formed. The coolant supplied to the space C through the part is sprayed onto the cutting insert 6.

  In the cutter configured as described above, as described above, the head 12a of the headed bolt 12 is accommodated in the housing portion 7b of the mounting hole 7, and the mounting member 8 is screwed into the female screw portion 7c. The distal end portion of the arbor 11 with the threaded portion 12c of the bolt 12 protruding from the rear end face of the mounting member 8 into the insertion portion 7d of the mounting hole 7 and the rotation of the mounting member 8 restrained by the locking screw 9. Will be placed on

  Then, a working tool is inserted from the opening 7a at the end of the mounting hole 7 and engaged with the engagement recess 12b of the headed bolt 12, and the headed bolt 12 is rotated to make the screw 12c a tip convex 11a. By screwing into the screw hole 11b, the cutter body 1 is drawn to the rear end side in the direction of the axis O via the mounting member 8, and the tip convex portion 11a is inserted into the insertion portion 7d of the mounting hole 7 and the key 11c is a key The cutter main body 1 is attached with its rear end face pressed against the tip end face of the arbor 11 by being fitted into the groove 1 b.

  During screwing of the screw portion 12c of the bolt 12 with a head, the mounting member 8 is restricted in rotation by the anti-rotation screw 9 in contact with the flat portion 8c, and attached with the female screw portion 7c of the mounting hole 7. The male screw 8a of the member 8 has a screw pitch smaller than the screw pitch of the screw 12c of the head bolt 12 or is twisted in the opposite direction to the screw 12c. Causes the mounting members 8 not to rotate together.

  Thus, in the cutter of the above configuration attached to the end of the arbor 11, the opening at the end of the cutter main body 1 is smaller in diameter than the housing portion 7b of the mounting hole 7 for housing the head 12a of the headed bolt 12 The opening 7a may have a size that allows insertion of a working tool that engages with the mating recess 12b. For this reason, even if the outer diameter from the axis O of the cutting edge 6a of the cutting insert 6 is a small diameter in the blade-tip-exchange-type cutter as in this embodiment, the interference between the mounting hole 7 and the insert mounting seat 5 is prevented. be able to.

  In addition, since the minimum number of parts required to attach the cutter main body 1 to the arbor 11 is only two, that is, the head bolt 12 and the attachment member 8 except for the locking screw 9, parts management becomes complicated. Can be avoided. In addition, mounting the mounting member 8 in the mounting hole 7 of the cutter main body 1 only requires forming the female screw portion 7 c in the cutter main body 1 and screwing the male screw portion 8 a of the mounting member 8. Since it is only necessary to form the holes 7 by turning with a centering bit and a thread cutting bit, the cutter body 1 does not become complicated.

  Further, in the cutter having the above configuration, the head 12a having a larger diameter than the screw portion 12c of the headed bolt 12 presses the cutter body 1 to the tip of the arbor 11 through the mounting member 8 as described above. Then, the cutter body 1 is attached to the arbor 11. For this reason, the head 12a of the headed bolt 12 presses the cutter main body 1 via the mounting member 8 at a position farther from the axis O than the screw portion 12c, so a large pressing force is ensured and the headed bolt The looseness of 12 can be prevented, and it becomes possible to fix and attach the cutter main body 1 to the arbor 11 reliably.

  Moreover, in the present embodiment, the flat portion 8 c parallel to the axis O is formed in the mounting member 8, and the anti-rotation screw 9 capable of coming into contact with the flat portion 8 c is screwed into the cutter body 1. Thus, the rotation of the mounting member 8 can be restrained to prevent the locking. Further, in the present embodiment, the female screw portion 7c of the mounting hole 7 and the male screw portion 8a of the mounting member 8 have a screw pitch equal to or less than the screw pitch of the screw portion 12c of the headed bolt 12, or The screw 12 is twisted in the opposite direction to the screw portion 12 c, which also prevents the attachment member 8 from being loosened by the rotation of the headed bolt 12 when the cutter body 1 is attached to the arbor 11.

  Further, in the present embodiment, the entire mounting member 8 for pressing and fixing the cutter main body 1 to the arbor 11 is accommodated in the mounting hole 7 and the inside of the mounting hole 7 at the rear end side with respect to the mounting member 8 Is an insertion portion 7d into which the tip end convex portion 11a of the arbor 11 is inserted. Therefore, the overall length in the direction of the axis O of the cutter body 1 can be shortened, and high rigidity can be secured particularly in the case of a cutter with a small diameter, and the tip convex portion 11 a of the arbor 11 and the actual implementation In the embodiment, since the key 11c can be directly fitted to the cutter main body 1 and the mounting strength can be improved, high processing accuracy can be obtained.

  However, in the first embodiment, the entire mounting member 8 is accommodated in the mounting hole 7 as described above, but as in the second embodiment of the present invention shown in FIGS. The rear end outer peripheral portion of 18 is formed in a flange shape protruding on the rear end face of the cutter body 1 so that the mounting member 18 is exposed to the outside from between the rear end face of the cutter body 1 and the tip end surface of the arbor 11 It may be done. 11 to FIG. 19, the same reference numerals are assigned to the parts common to the first embodiment shown in FIG. 1 to FIG.

  In the cutter main body 1 in the second embodiment, the mounting hole 7 is enlarged by one step toward the outer peripheral side on the rear end side of the accommodation portion 7b and extends with a short inner diameter at a short length, and then goes to the rear end side. A tapered portion 7e gradually expands in diameter according to the shape, and a female screw portion 7c is formed on the rear end side of the tapered portion 7e. Further, in the present embodiment, the key groove 1 b is not formed in the cutter body 1, and the rear end surface of the cutter body 1 is an annular surface perpendicular to the axis O.

  The attachment member 18 attached to the attachment hole 7 of the cutter main body 1 is integrally formed in a multistage cylindrical shape as shown in FIG. 19 by a metal material such as steel material, and its tip end portion (FIGS. The lower portion 18a of the mounting hole 7 has a disk shape that can be fitted into a portion of the mounting hole 7 enlarged in diameter at the rear end side of the housing portion 7b. The tapered portion 18b has a taper angle equal to that of the tapered portion 7e and gradually increases in diameter toward the rear end side. At the rear end of the tapered portion 18b, an external thread 18c threadable into the female thread 7c is provided. It is formed.

  Further, the rear end side of the male screw portion 18c is a disc-like flange portion 18d which is slightly constricted and then protrudes to the outer peripheral side. The outer diameter of the flange portion 18d is the rear end of the cutter main body 1 Approximately equal to the outer diameter of the part. Further, in the present embodiment, the flange portion 18d is formed with a pair of key grooves 18e into which the keys 11c of the end face of the arbor 11 can be fitted. In the present embodiment, the female screw portion 7c of the mounting hole 7 and the male screw portion 18c of the mounting member 18 are twisted in the same direction as the cutter rotation direction T at the time of cutting along the rear end side in the axis O direction. There is.

  On the other hand, the inner peripheral portion of the mounting member 18 is an insertion portion 18f into which the tip end convex portion 11a of the arbor 11 is fitted and inserted as shown in FIGS. The male screw portion 18 c is formed on the outer peripheral side of the insertion portion 18 f. Further, from the insertion portion 18f to the tip end surface of the mounting member 18, a through hole 18g smaller in diameter than the insertion portion 18f and the head 12a of the head bolt 12 is formed as a through hole 18g through which the screw portion 12c can be inserted. It is in communication.

  Such a mounting member 18 projects the screw portion 12c of the headed bolt 12 from the through hole 18g to the insertion portion 18f while the head 12a of the headed bolt 12 is housed in the housing portion 7b of the mounting hole 7 While being screwed, the male screw 18 c is screwed into the female screw 7 c of the mounting hole 7 to be attached to the cutter body 1.

  Then, in this state, the cutter main body 1 is disposed at the tip of the arbor 11, and the screw of the headed bolt 12 is inserted by the working tool inserted from the opening 7a at the tip of the mounting hole 7 as in the first embodiment. By screwing 12 c into the screw hole 11 b of the arbor 11, the cutter body 1 is pressed and attached to the tip end surface of the arbor 11 via the mounting member 18. At this time, in the present embodiment, the key 11 c of the arbor 11 is fitted into the key groove 18 e of the mounting member 18, and the flange portion 18 d is sandwiched between the rear end surface of the cutter body 1 and the tip end surface of the arbor 11.

  Also in the cutter of the second embodiment having such a configuration, the opening 7a at the tip of the cutter main body 1 is an opening 7a having a diameter smaller than that of the accommodation portion 7b of the attachment hole 7 and into which the working tool can be inserted. Even if it is a small diameter blade replaceable cutter, interference between the mounting hole 7 and the insert mounting seat 5 can be prevented. Further, since the cutter main body 1 can be attached to the arbor 11 with only the minimum number of two parts of the head bolt 12 and the mounting member 18, parts management can be simplified and the mounting hole 7 is formed in the cutter main body 1 Since only turning is sufficient, the manufacturing of the cutter body 1 will not be complicated.

  And also in this embodiment, the cutter main body 1 is arbor 11 via the mounting member 8 at a position where the head 12a larger in diameter than the screw 12c of the head bolt 12 is farther from the axis O than the screw 12c. Is attached to the tip of the Therefore, a large pressing force can be secured, and the loosening of the head bolt 12 can be prevented, so that the cutter body 1 can be securely fixed and attached to the arbor 11.

  Moreover, in the present embodiment, the insertion portion 18 f into which the tip convex portion 11 a of the arbor 11 is inserted is formed in the attachment member 18 and an external thread portion to be screwed into the internal thread portion 7 c of the attachment hole 7 of the cutter main body 1 18 c is formed on the outer peripheral side of the insertion portion 18 f. Therefore, the male screw 18c and the female screw 7c can be made larger in diameter as compared with the first embodiment, so that the mounting member 18 can be attached to the cutter body 1 more stably. Processing accuracy can also be stabilized.

  Further, in this embodiment, as the female screw portion 7c of the mounting hole 7 and the male screw portion 18c of the mounting member 18 move toward the rear end side in the direction of the axis O, in the same direction as the cutter rotation direction T at cutting. It is formed to twist. Therefore, even if a cutting load acts in the direction opposite to the cutter rotational direction T at the time of cutting, the mounting screw 18 is engaged with the mounting member 18 in which the flange portion 18d is sandwiched between the rear end face of the cutter body 1 and the tip end face of the arbor 11. Since the portion 18c acts in the direction of being screwed into the female screw portion 7c, it is possible to prevent the attachment member 18 from being loosened. Also in the second embodiment, the mounting member 18 may be fixed by forming a flat portion and allowing a locking screw to abut.

  In the first and second embodiments, the present invention has been described as being applied to an indexable cutter, but the cutting tip having the cutting edge 6a formed on the outer periphery of the tip end portion of the cutter main body 1 is low. It is of course possible to apply the present invention to a brazed type cutter joined by attachment or a solid type cutter in which the cutting edge 6a is directly formed on the outer periphery of the tip end portion of the cutter main body 1.

DESCRIPTION OF SYMBOLS 1 cutter main body 1b, 18e Key groove 2 cutting blade part 3 mounting part 5 insert mounting seat 6 cutting insert 6a cutting blade 7 mounting hole 7a opening part 7b accommodation part 7c female screw part 7d, 18f insertion part 8, 18 mounting member 8a, 18c Male thread 8b, 18g Through hole 8c Flat part 9 Locking screw 11 Arbor 11a Tip convex part 11b Screw hole 11c Key 12 Headed bolt 12a Head 12b Engage recess 12c Thread O Axis of cutter main body 1 T cutter Direction of rotation

Claims (6)

A cutting blade is disposed on an outer periphery of a distal end portion of a cutter main body rotated about an axis, and a mounting hole penetrating the cutter main body along the axis is formed in a central portion of the cutter main body,
The mounting hole is formed with an opening at the tip of the cutter body, a housing formed at the rear end of the opening and capable of housing the head of the headed bolt, and a screw at the inner periphery. Equipped with a threaded internal thread,
Attached to the female screw portion is a mounting member having an outer peripheral portion with a male screw portion that can be screwed into the female screw portion,
The mounting member is characterized in that a through hole having an inner diameter smaller than that of the head portion is formed, through which the screw portion of the headed bolt can be inserted while the head portion is housed in the housing portion. cutter. The mounting member has a flat portion parallel to the axis, and
The cutter according to claim 1, wherein a locking screw capable of abutting on the flat portion is screwed into the cutter body. The mounting member is entirely housed in the mounting hole,
3. The mounting hole according to claim 1, wherein the mounting hole on the rear end side of the mounting member is an insertion portion into which a tip convex portion provided at the tip of the arbor is inserted. cutter.   The internal thread of the mounting hole and the external thread of the mounting member have a thread pitch smaller than the thread pitch of the threaded portion of the headed bolt, or in the opposite direction to the threaded portion of the headed bolt A cutter according to claim 3, characterized in that it is twisted. The rear end outer peripheral portion of the mounting member is formed in a flange shape that overhangs the rear end surface of the cutter main body,
The rear end inner peripheral portion of the mounting member is an insertion portion which communicates with the through hole and into which the tip end convex portion of the arbor is inserted,
The cutter according to claim 1 or 2, wherein the male screw portion is formed on the outer peripheral side of the insertion portion.   The female screw portion of the mounting hole and the male screw portion of the mounting member are twisted in the same direction as the rotation direction of the cutter main body at the time of cutting as it goes to the rear end side in the axial direction. The cutter according to item 5.

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