JP6556186B2 - Attachment for threading dies - Google Patents

Description

  The present invention relates to an attachment for a threading die.

  Conventionally, when male thread machining is performed at a machining center, a collet die holder with a threading die attached is attached to a tool holder attached to a spindle (for example, see Patent Document 1). In addition, a threading die is attached to an attachment used in a lathe and a drilling machine, and the attachment is attached to a tool holder for a machining center (for example, see Patent Document 2).

Japanese Utility Model Publication No. 5-80625 JP-A-10-309628

  In the configurations described in Patent Documents 1 and 2, chips at the time of processing are stored in a chip hole of a threading die or a holder that holds the threading die. Chips that cannot be stored suddenly enter between the workpiece and the cutting edge of the threading die, resulting in chip biting and chip clogging, resulting in deterioration of the surface condition of the workpiece and defective thread accuracy. May occur.

  In addition, since the die machining for forming the external thread is internal cutting, the cutting fluid is supplied from the outside to the machining portion. In such external lubrication, the cutting fluid is not directly supplied to the cutting edge of the threading die. Therefore, there is a problem that the effect of cooling the cutting heat generated at the cutting edge is low, the thermal wear of the cutting edge is likely to proceed, and the constituent cutting edge due to heat generation during cutting is likely to be generated.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an attachment for a thread cutting die that prevents chip biting and chip clogging and enables stable processing in male thread processing by a machining center.

  According to one aspect of the present invention, a threaded die attachment comprising a holder to which a threaded die can be attached, wherein the threaded die attachment is formed with a liquid passage penetrating along the central axis. By attaching and using the threading die attachment to a machining center having a lubrication function, the cutting fluid is passed from the rear end to the front end of the threading die attachment through the liquid passage and ejected from the front end. An attachment for a threading die is provided.

  According to another aspect of the present invention, the apparatus further comprises a shank portion that accommodates the holder, and an elastic member is disposed between the holder and the shank portion, and the elastic member is elastically deformed, whereby the holder and The shank portion is relatively movable in the axial direction or the radial direction.

  According to the aspect of the present invention, in male thread processing by a machining center, there is a common effect of providing a threading die attachment that prevents chip biting and chip clogging and enables stable processing.

It is a fragmentary sectional view of the attachment for threading dies by the embodiment of the present invention. It is a front view of the attachment for threading dies of FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a partial cross-sectional view of a threading die attachment 1 according to an embodiment of the present invention. FIG. 2 is a front view of the threading die attachment 1 of FIG. The threading die attachment 1 includes a holder 10, a shank portion 20, and a fixing bolt 30.

  The holder 10 has a cylindrical shape as a whole and is open at both ends. The holder 10 has a large diameter portion 11 having a larger outer diameter and a small diameter portion 12 having a smaller outer diameter. A threading die 40 is attached to the opening on the large diameter portion 11 side. That is, in the vicinity of the opening on the large-diameter portion 11 side, two set screws 13 are provided at symmetrical positions with respect to the central axis, whereby the threading die 40 is fixed. In the axial direction of the threading die attachment 1, the side on which the threading die 40 is attached is referred to as a “front” side, and the opposite side is referred to as a “rear” side.

  Four slide grooves 14 extending in the axial direction are formed on the outer peripheral surface of the small diameter portion 12 of the holder 10 at equal intervals along the circumferential direction. Two annular grooves are formed on the outer peripheral surface of the small-diameter portion 12 behind the four slide grooves 14 so as to be separated from each other in the axial direction, and an elastic member 15 is disposed in each of the annular grooves. The elastic member 15 is, for example, an O-ring.

  The shank portion 20 has a cylindrical shape formed to have substantially the same outer diameter as the large diameter portion 11 of the holder 10, and both ends are open. The holder 10 is accommodated in the shank portion 20. Therefore, the inner diameter of the shank portion 20 is set slightly larger than the outer diameter of the small diameter portion 12 of the holder 10. Further, the shank portion 20 is formed longer in the axial direction than the small diameter portion 12 of the holder 10.

  On the outer peripheral surface of the shank portion 20, screw holes into which the four hexagon socket head bolts 21 are screwed are formed at equal intervals along the circumferential direction. The hexagon socket head cap bolt 21 holds the hard sphere 22 so that the hard sphere 22 is disposed in the slide groove 14 of each of the screw hole and the holder 10. Therefore, the diameter of the screw hole is set slightly larger than the diameter of the hard sphere 22. The rigid sphere 22 is slightly movable in the radial direction of the holder 10 between the hexagon socket head bolt 21 and the slide groove 14. The slide groove 14 of the holder 10 is formed on the outer peripheral surface of the small-diameter portion 12 of the holder 10 so as to restrict the movement of the rigid sphere 22 in the circumferential direction and to allow the movement of the rigid sphere 22 in a predetermined distance in the axial direction. One annular groove is formed on each of the annular front end face and the rear end face of the shank portion 20, and the elastic member 23 is disposed in each of them. The elastic member 23 is, for example, an O-ring.

  The fixing bolt 30 includes a bolt main body 31 and a flange portion 32 provided at the rear portion of the bolt main body 31. A male screw is formed on the outer peripheral surface of the bolt body 31. The fixing bolt 30 is screwed into the opening at the rear end of the holder 10 so that the shank part 20 is sandwiched between the fixing bolt 30 and the holder 10. That is, the front end surface of the shank portion 20 is in contact with the rear end surface of the large-diameter portion 11 of the holder 10 via the elastic member 23, and the rear end surface of the shank portion 20 is connected to the flange portion of the fixing bolt 30 via the elastic member 23. 32 abuts the front end face.

  The fixing bolt 30 has a through hole formed along the central axis. Therefore, the threading die attachment 1 as a whole is formed with a liquid passage 50 penetrating along the central axis as indicated by an arrow in FIG.

  The threading die attachment 1 is attached by fitting the outer peripheral surface of the shank portion 20 to a tool holder (not shown) of a machining center. Therefore, the holder 10 of the threading die attachment 1 and the fixing bolt 30 screwed to the holder 10 are not engaged with the tool holder of the machining center. Therefore, the holder 10 is movable relative to the shank portion 20 and eventually the machining center in a state where the threading die attachment 1 is attached to the tool holder of the machining center.

  That is, since the elastic member 15 can be elastically deformed, the holder 10 is movable in the radial direction, that is, in a direction away from the central axis of the shank portion 20. Further, since the elastic member 23 can be elastically deformed, the holder 10 is movable in the axial direction. Note that the holder 10 cannot rotate around the central axis due to the engagement between the hard sphere 22 and the slide groove 14.

  By the relative movement of the holder 10, it becomes possible to absorb an error at the time of male thread processing. That is, the relative movement in the axial direction of the holder 10 absorbs an error between the thread lead of the male screw to be cut and the amount of movement of the threading die attachment 1 by N / C control of the machining center, and makes them coincide. The male thread can be machined in the state. Further, the relative movement in the radial direction of the holder 10 absorbs an error between the central axis of the threading die 40 and the rotational axis of the threading die attachment 1, and the male threading is performed in a state in which these axes are aligned. be able to. Further, the relative movement in the radial direction of the holder 10 absorbs an error between the center axis of the threading die 40 and the center axis of the workpiece attached to the machining center, and the male thread is processed in a state in which these axes match. can do.

  As described above, the threading die attachment 1 has the liquid passage 50 penetrating along the central axis. Therefore, when the threading die attachment 1 is used by being attached to a machining center having an oil supply function, the cutting fluid is passed from the rear end to the front end of the threading die attachment 1 through the liquid passage 50 from the front end. Can be ejected.

  Therefore, the cutting fluid can be directly supplied to the cutting edge of the threading die 40 by supplying the cutting fluid through the liquid passage 50 during the external thread machining for performing the internal cutting. As a result, the effect of cooling the cutting heat is higher than in the conventional case where oil is supplied to the machined part from the outside, it is possible to suppress the progress of wear of the cutting edge, and it is also possible to prevent the generation of the constituent cutting edge. . Further, since the cutting fluid that has passed through the inside of the threading die attachment 1 is ejected from the tip, chips during processing are forcibly discharged together with the cutting fluid without being stored in the chip hole 41 or the holder 10. Therefore, it becomes possible to prevent chip biting and chip clogging. As a result, stable processing is possible, and high-precision and high-efficiency screws can be processed with a good surface state.

  The present invention has an arbitrary configuration as long as the cutting fluid can be passed from the rear end to the front end and ejected from the front end through the liquid passage by being attached to a machining center having an oil supply function. It can be applied to an attachment for threading dies. Moreover, in embodiment mentioned above, although it had two types of elastic members (the elastic member 15 and the elastic member 23), you may make it have only any one.

DESCRIPTION OF SYMBOLS 1 Attachment for thread cutting dies 10 Holder 11 Large diameter part 12 Small diameter part 13 Set screw 14 Slide groove 15 Elastic member 20 Shank part 21 Hexagon socket head bolt 22 Hard ball 23 Elastic member 30 Fixing bolt 31 Bolt body 32 Flange part 40 Die 41 Chip Hole 50 liquid passage

Claims (1)

A threading die attachment having a holder to which a threading die can be attached, wherein the threading die attachment has a fluid passage extending along a central axis, and the threading die attachment is provided with a lubrication function. By using it attached to a machining center equipped with, through the liquid path, the cutting fluid can be passed from the rear end to the front end of the threading die attachment and ejected from the front end.
The holder further includes a shank portion, and an elastic member is disposed between the holder and the shank portion, and the elastic member is elastically deformed, whereby the holder and the shank portion are axially or radially separated. Move relative to the direction,
The elastic member is Ri O-ring der,
Attachment for threading die outer peripheral surface of the shank portion and said Rukoto that match fitted to the tool holder of the machining center.

Images