JP5251063B2 - Cutting tools - Google Patents

Description

  The present invention relates to a cutting tool in which a tool holder attached to a machine tool is provided with a tool body such as a drilling tool, and more particularly to a cutting tool having a deflection adjusting function.

  When performing cutting such as drilling on a workpiece using a machine tool etc., a tool body such as a drilling tool is attached to the tip of the tool holder attached to the spindle of the machine tool, and the spindle of the machine tool is set to the axis. A desired process is performed on a workpiece by rotating it around.

  In such a cutting process, in order to form a processed hole with high accuracy, it is necessary to fix the axis of the tool holder and the axis of the drilling tool so that they match well to prevent the drilling of the drilling tool. is there. That is, in this cutting tool, the runout of the drilling tool must be adjusted with high accuracy.

Therefore, as a conventional example, for example, Patent Document 1 discloses that a tool attached to the tip portion is displaced by displacing the axis of the tip portion of the tool holder by rotating a screw member that presses a part of the tool holder. There is disclosed a device provided with a shake correcting means in which the central axis of the main body is aligned with the rotational axis of the tool holder. The vibration correcting means in the cutting tool of this conventional example is provided with a screw member screwed along a direction perpendicular to the axis from the radially outer side of the tool body toward the radially inner side. By screwing, a pressing force directed radially inward and toward the tip of the tool is applied to the tool main body, and the axis of the tip of the tool main body is displaced to correct the tool runout.
JP 2001-138162 A

  However, the conventional shake correcting means as described above has the following problems. That is, in the conventional example, as described above, the screw member is inserted along the direction perpendicular to the axis, and is generated by the component force in the diagonally inner direction and the tool tip side that is generated when the screw member comes into contact with the tool body. The shake is corrected. Therefore, when inserting the screw member, in addition to the force for correcting the runout, a force that does not contribute to the runout correction is also given to the tool body. In order to perform this, a large force is required as a whole, and there is a problem that the shake adjustment cannot be performed easily and simply.

  This invention is made in view of such a subject, and it aims at providing the cutting tool which can perform easily and simply the run-out adjustment of the tool main body with which the tool holder was equipped with the minimum force. To do.

In order to solve the above problems, the present invention proposes the following means.
That is, the cutting tool according to the present invention is a cutting tool provided with a tool body extending along the axis at the tip of a tool holder that is attached to the spindle of a machine tool and rotated about the axis, and the outer periphery of the tool holder An annular groove having a tapered annular surface facing the outer peripheral side toward the distal end side is provided on the side surface, and a ring member covering the annular groove is slidably fitted on the outer peripheral side surface, and the ring threaded hole communicating with the annular groove is provided is drilled obliquely toward the outer periphery of the member radially inward and the tool distal end side, the angle between the axis of the tool holder with the axis of the threaded hole 45 And the angle formed by the axis of the screw hole and the annular surface of the annular groove is 90 °, and the runout adjusting screw screwed into the screw hole is connected to the annular surface of the annular groove. Press the tool The main body is displaced in the radial direction to adjust the deflection of the tool main body.

  In the cutting tool having such a feature, the ring member is slidable with respect to the tool holder, that is, can be rotated in the circumferential direction. Accordingly, the runout adjusting screw is attached to the tool body in the circumferential direction of the tool holder. The tip can be arranged on the side inclined toward the outer peripheral side. When the runout adjustment screw is screwed in, the screw hole communicates with the annular groove. Therefore, the tip of the runout adjustment screw comes into contact with the annular surface of the annular groove, and further screwed in, the tool holder moves to the tool tip side and the diameter. It is pressed in an oblique direction toward the inner side.

  Thereby, the tool main body located in the front-end | tip part of a tool holder can be displaced to a radial inside according to the location which has arrange | positioned the shake adjustment screw, and it becomes possible to adjust the shake of this tool main body. In addition, since it is possible to exert a force directly on the tool holder in the radial direction and toward the tool tip side, the pressing force by the runout adjustment screw can efficiently contribute to runout adjustment. The shake adjustment can be performed with.

  The cutting tool according to the present invention is characterized in that a tip of the runout adjustment screw is formed in a flat shape and is in surface contact with the annular surface perpendicularly.

  Since the runout adjustment screw comes into contact with the surface perpendicular to the annular surface of the annular groove, the pressing force by the runout adjustment screw can be reliably and stably transmitted to the tool holder.

  Furthermore, the cutting tool according to the present invention is characterized in that a plurality of the runout adjustment screws are arranged at equal intervals in the circumferential direction on a plane orthogonal to the axis. This makes it possible to adjust the deflection flexibly and reliably.

  According to the cutting tool of the present invention, the runout adjustment screw exerts a force directly toward the inner side in the radial direction of the tool holder and toward the tip end of the tool, so that the runout of the tool body can be easily and easily adjusted with a minimum force. It can be performed.

  Hereinafter, embodiments of the cutting tool of the present invention will be described in detail with reference to FIGS. 1 and 2. FIG. 1 is a partially cutaway longitudinal sectional view showing a cutting tool according to an embodiment of the present invention, and FIG. 2 is a partially enlarged view of a tool holder of the cutting tool according to this embodiment.

  As shown in FIG. 1, the cutting tool 1 of the present embodiment includes a tool holder 10 whose rear end side (upper side in FIG. 1) is attached to a main shaft of a machine tool and rotated around an axis O, and the tool holder 10. The tool body 20 is a tool body 20 as a drilling tool (reamer) that is press-fitted into a mounting hole 11a drilled in the tip portion and extends along the axis O to the tip side (lower side in FIG. 1).

  The tool main body 20 has a long cylindrical shape formed around the axis O, and the tip end side of the tool main body 20 serves as a processing portion 21 that directly processes a workpiece, and the rear end of the tool main body 20 The side is a mounting shank portion 22 that is press-fitted into the mounting hole 11a of the tool holder 10 and fixed.

  Further, a pilot 24 having a one-step smaller diameter than the processing portion 21 is provided on the tip surface 23 of the tool body 20. Further, the tool body 20 is provided with a coolant supply hole 26 that opens to the rear end surface 25 of the mounting shank 22 and extends to the tool front end side along the axis O to reach a predetermined position. A coolant discharge hole 27 that extends obliquely from the supply hole 26 toward the radially outer side of the tool body 20 and toward the tip end side of the tool and opens to the outer peripheral surface of the tool body 20 is formed.

  A concave portion 28 is formed on the distal end side of the processing portion 21 of the tool body 20 so as to open toward the distal end side of the tool and the outer side in the tool radial direction, and the coolant discharge extending from the aforementioned coolant supply hole 26 is formed in the concave portion 28. A hole 27 is opened. And in this embodiment, the insert 29 provided with the cutting blade is attached to the tool rotation direction back side of the recessed part 28.

  In addition, a plurality of guide pads 30 that are made of a hard material and whose outer shape forms a substantially oval plate shape are arranged on the outer peripheral portion of the processing portion 21 of the tool body 20 so as to extend in parallel with the axis O. In the present embodiment, the six guide pads 30 are arranged at equal intervals in the circumferential direction.

  As shown in FIG. 1, the tool holder 10 has a substantially multi-stage cylindrical shape formed along the axis O. A tip end portion of the tool holder 10 is a tool mounting portion 11 having a cylindrical shape with a mounting hole 11a for inserting the tool body 20 formed therein. The inner diameter of the mounting hole 11a is substantially the same as the outer diameter of the mounting shank portion 22 of the tool main body 20, and the mounting hole 11a and the mounting shank portion 22 are in close contact with each other when the tool main body 20 is press-fitted. It is like that.

  A ring attachment portion 12 is formed on the rear end side of the tool mounting portion 11 in the tool holder 10, and a ring member 17 is attached to the ring attachment portion 12. The ring mounting portion 12 is positioned immediately on the rear end side of the tool mounting portion 11 and has a ring mounting surface 13 having an outer diameter larger than that of the tool mounting portion 11, and on the rear end side of the ring mounting surface 13. And a large-diameter portion 14 having an outer diameter one step larger than that of the ring mounting surface 13, and a step portion between the ring mounting surface 13 and the large-diameter portion 14 is perpendicular to the axis O. The contact step 15 is a flat surface.

  The ring mounting surface 13 is formed with a V-shaped groove (annular groove) 16 in which the outer peripheral surface of the ring mounting surface 13 is formed in an annular shape centering on the axis O and the cross section thereof is formed in a V shape. Of the two annular surfaces 16a and 16b constituting the V-shaped groove 16, the annular surface 16a on the tool tip side is pressed by a deflection adjusting screw 19 described later. The angle formed by the two annular surfaces 16a and 16b is approximately 90 °, and is symmetric with respect to a plane perpendicular to the axis O.

  The ring member 17 has a substantially cylindrical shape centered on the axis O, and the inner diameter of the inner peripheral surface 17a is formed substantially the same as the outer diameter of the ring mounting surface 13 of the ring mounting portion 12, and The diameter of the surface 17b is formed substantially the same as the diameter of the large-diameter portion 14 of the ring mounting portion 12, and the length of the ring member 17 in the axis O direction is the length of the ring mounting surface 13 of the ring mounting portion 12 in the axis O direction. It is almost the same. Further, an end surface of the ring member 17 facing the tool rear end side is a contact end surface 17c.

  The ring member 17 is attached to the ring of the tool holder 10 so that the inner peripheral surface 17a is fitted on the ring mounting surface 13 and the contact end surface 17c is in contact with the contact step portion 15. It is attached to the part 12. At this time, the inner peripheral surface 17a of the ring member 17 and the ring mounting surface 13 are slidable, and the ring member 17 can freely rotate in the circumferential direction.

  In the ring member 17, screw holes 18 that are formed obliquely from the outer peripheral surface 17b to the inner peripheral surface 17a toward the tool tip side are evenly spaced in the circumferential direction on a plane orthogonal to the axis O. A plurality of openings are formed in the inner peripheral surface 17a of the ring member 17 of the screw hole 18 so as to communicate with the V-shaped groove 16 in a state where the ring member 17 is attached to the ring attachment portion 12 of the tool holder 10. It has become. In the present embodiment, the angle formed by the axis P of the screw hole 18 of the ring member 17 and the axis O of the tool holder 10 is 45 °, and the axis P of the screw hole 18 and the tool tip of the V-shaped groove 16 are formed. The angle formed by the annular surface 16a on the side is 90 °.

  Each of the screw holes 18 is inserted with a shake adjusting screw 19 whose tip is a flat pressing surface 19a perpendicular to the axis P. By screwing the shake adjusting screw 19, the V-shaped groove 16 is inserted. The annular surface 16a on the tool tip side is configured to be pressed vertically.

  Further, as shown in FIG. 1, a gripping portion 10a that can be gripped by an arm of an ATC (automatic tool changer) of a machine tool, for example, is formed on the tool rear end side of the ring mounting portion 12 in the tool holder 10. The rear end portion of the tool holder 10 is an arbor 10b for attaching the tool holder 10 to a main shaft of a machine tool such as a machining center.

  Cutting using the cutting tool 1 configured as described above will be described. In the cutting tool 1 of the present embodiment, the arbor 10b is attached to the main shaft of the machine tool and rotated around the axis O, and the processing portion 21 of the tool body 20 is inserted into a prepared hole formed in advance in the workpiece. At this time, the inner wall surface of the prepared hole is finished into a processed hole having a predetermined inner diameter by the cutting blade of the insert 29. Further, when cutting, the guide pad 30 and the inner wall surface of the machined hole are slidably guided to suppress vibration generated when the reamer is rotated at high speed in the machined hole. Can be formed with high accuracy. Furthermore, the coolant is supplied to the coolant supply hole 26 from the spindle of the machine tool, so that the lubrication of the cutting of the insert 29 can be improved.

  In such a cutting process, in order to form the machining hole with higher accuracy, it is necessary to match the axis of the tool holder 10 and the axis of the tool body 20 with high accuracy to prevent the tool body 20 from swinging. There is. That is, the deflection of the tool body 20 must be adjusted with high accuracy.

  When performing such runout adjustment, first, the ring member 17 is rotated in the circumferential direction so that the runout adjustment screw 19 is in the circumferential direction of the tool holder 10 and the tip of the tool body 20 is inclined to the outer circumferential side. To be placed. Then, when the shake adjusting screw 19 is screwed in with an adjusting tool such as a screwdriver, for example, the screw hole 18 communicates with the V-shaped groove 16, so that the pressing surface 19 a at the tip of the shake adjusting screw 19 is formed on the V-shaped groove 16. By reaching the annular surface 16a on the tool tip side and further screwing the runout adjustment screw 19, the annular surface 16a in the inclination angle direction of the screw hole 18, that is, in the tool radial direction inner side and in the oblique direction toward the tool tip side. Is pressed.

  Thereby, a force can be exerted on the tool mounting portion 11 located at the tip of the tool holder 10, and the axis of the mounting hole 11 a can be displaced radially inward depending on the location where the runout adjustment screw 19 is disposed. it can. Accordingly, the axis of the tool body 20 mounted in the mounting hole 11a can also be displaced, and the runout can be adjusted.

  As described above, it is possible to adjust the deflection by displacing the axis of the tool mounting portion 11 by applying a force to the tool holder 10 toward the inside in the tool radial direction and toward the tip of the tool. In the embodiment, since the shake adjusting screw 19 can directly exert a force in this direction, the pressing force by the shake adjusting screw 19 can efficiently contribute to the shake adjustment. Therefore, since there is no loss of force, it is possible to perform shake adjustment with a small force without applying an excessive force.

  Further, since the pressing surface 19a of the deflection adjusting screw 19 comes into contact with a surface perpendicular to the annular surface 16a on the tool tip side of the V-shaped groove 16, the pressing force by screwing the deflection adjusting screw 19 is stably transmitted. Therefore, it is possible to perform the shake adjustment with certainty.

  Furthermore, since a plurality of screw holes 18 and deflection adjusting screws 19 screwed into the screw holes 18 are arranged at equal intervals in the circumferential direction on a plane orthogonal to the axis O, the screw holes 18 and the deflection adjusting screws 19 can be pressed from a desired direction, and are flexible and reliable. Therefore, it is possible to perform shake adjustment.

  As mentioned above, although the cutting tool 1 which is embodiment of this invention was demonstrated, this invention is not limited to this, It can change suitably in the range which does not deviate from the technical idea of the invention. For example, in the present embodiment, the case where the tool body 20 attached to the tool holder 10 is a reamer has been described. However, the present invention is not limited to this. For example, a tool body such as a drill or an end mill is attached. May be.

It is the longitudinal cross-sectional view which fractured | ruptured a part which shows the cutting tool which is embodiment of this invention. It is the elements on larger scale of the tool holder of the cutting tool in this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cutting tool 10 Tool holder 11a Mounting hole 13 Ring attachment surface (outer peripheral side surface)
16 V-shaped groove (annular groove)
16a annular surface 17 ring member 18 screw hole 19 runout adjustment screw 20 tool body O axis

Claims (3)

In a cutting tool provided with a tool body extending along the axis at the tip of a tool holder that is attached to the spindle of a machine tool and rotated about the axis,
An annular groove having a tapered annular surface facing the outer peripheral side toward the distal end side is provided on the outer peripheral side surface of the tool holder, and a ring member covering the annular groove is slidably attached to the outer peripheral side surface. Fitted,
A screw hole that is formed obliquely from the outer peripheral side of the ring member to the radially inner side and toward the tool tip side and communicates with the annular groove is provided,
The angle formed by the axis of the screw hole and the axis of the tool holder is 45 °, and the angle formed by the axis of the screw hole and the annular surface of the annular groove is 90 °.
A runout adjusting screw screwed into the screw hole presses the annular surface of the annular groove to displace the tool body in the radial direction to adjust the runout of the tool body. .   The cutting tool according to claim 1, wherein a tip of the runout adjustment screw is formed in a flat shape and is in surface contact with the annular surface perpendicularly.   The cutting tool according to claim 1 or 2, wherein a plurality of the runout adjustment screws are arranged at equal intervals in the circumferential direction on a plane orthogonal to the axis.

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