JP2008105133A - Screw machining portion swapping type screw machining tool and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily machine a joining structure, and as a result, to easily manufacture a tool without requiring severe machining accuracy of the members and portions composing the joining structure. <P>SOLUTION: A screw machining portion swapping type screw machining tool 1 comprises: a shank portion 3; a screw machining portion 2 detachably connected to the shank portion; the joining structure, such as a bolt 4, for detachably connecting the shank portion to the screw machining portion; and a fitting structure for mutually positioning the shank portion and the screw machining portion. The fitting structure has: a plurality of independently projected portions 3d provided on one of end faces of the shank portion and the screw machining portion facing each other; and a plurality of independent recessed portions 2e which are provided on the other one of end faces of the shank portion and the screw machining portion facing each other, and closely fit to a plurality of the projected portions respectively. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a threading tool having a shank part and a threading part, such as a cutting tap, a build-up tap, and a thread milling cutter, and more particularly to a threading tool of a threading part exchange type.

  In conventional threading tools, the material of the threaded part is harder than the shank part so that the threaded part is less likely to be worn or chipped due to repeated use of the tool, and the threaded part and the shank part are welded together. However, there is an inconvenience that it becomes difficult to reuse the tool when a defect occurs.

In recent years, in a drilling tool, a shank part, a drilling part that is separably coupled to the shank part, a screw structure as a coupling structure that separably couples the shank part and the drilling part, and The thing which made the excavation part exchangeable by providing the fitting structure which positions a shank part and a drilling part mutually is used (refer patent document 1).
JP 2003-285213 A

  However, in the above-described excavating part exchanging drilling tool, the fitting structure is simply formed by a corrugated uneven shape consisting of a plurality of protrusions and grooves extending in parallel with each other. Although it is possible to position each other in the direction of rotation, it is not possible to position each other in the extending direction of the ridges and grooves among the directions intersecting the central axis, and it is also necessary to perform positioning with a screw structure that is a coupling structure Therefore, there has been a problem that extremely strict processing accuracy is required for the screw member and the shank portion constituting the screw structure.

  Therefore, in order to replace the threaded part and reuse the tool even if a defect occurs in the threaded part, the structure of the drilling part replaceable drilling tool described above is applied to the threaded tool so that the threaded part can be reused. Even if the replaceable threading tool is configured, there is a problem that it is difficult to manufacture a coupling structure of the threading tool.

  Therefore, the present invention improves the conventional threading tool in which the threaded portion and the shank portion are integrally joined by welding, and even if a defect occurs in the threaded portion, the threaded portion is replaced and the tool is replaced. An object of the present invention is to provide a threaded part exchange-type threading tool that can be reused and that facilitates the manufacture of a joint structure between the threaded part and the shank part.

  In order to achieve the above object, a threaded part replaceable threading tool according to claim 1 of the present invention includes a shank part, a threaded part separably coupled to the shank part, the shank part and the screw. A coupling structure that detachably couples the processed portion; and a fitting structure that positions the shank portion and the threaded portion relative to each other, wherein the fitting structure includes the shank portion and the threaded portion. The plurality of protrusions provided on one of the end surfaces facing each other, and the plurality of protrusions provided on the other of the end surfaces facing each other of the shank portion and the threaded portion. And a plurality of independent recesses that are closely fitted to each other.

  According to a fifth aspect of the present invention, there is provided a method for manufacturing a threaded part replacement type threading tool according to the present invention, wherein the plurality of concave parts independent of each other are used as mold forming parts. The mold processing of the plurality of concave portions of the fitting structure is performed using a mold having convex portions that coincide with a part.

  In such a threaded part replacement type threading tool of the present invention, the fitting structure has independent one another provided on one of the mutually facing end surfaces of the shank part and the threaded part. The plurality of convex portions and the plurality of independent concave portions provided on the other of the end faces facing each other of the shank portion and the threaded portion are closely fitted to each other so that the shank portion and the threaded portion are closely fitted to each other. Are mutually positioned, and in this positioning state, the coupling structure couples the shank portion and the threaded portion in a separable manner.

  Therefore, according to the threaded part replacement type threading tool of the present invention, in the fitting structure, the plurality of independent convex parts and the plurality of concave parts are closely fitted, and the rotational direction around the central axis is Because positioning is performed in the direction intersecting with the central axis, there is no need to perform positioning with the coupling structure, so strict machining accuracy is required for members and parts that constitute the coupling structure such as screw structures. Can be made unnecessary, and the machining of the coupling structure and thus the manufacture of the tool can be facilitated.

  In the threaded part exchange type threading tool of the present invention, the shank part and the threaded part may be made of the same material, but the shank part and the threaded part are made of different materials. In this way, the threaded portion is less likely to be worn or chipped due to repeated use of the tool, and the number of times the threaded portion is replaced can be reduced.

  Further, in the threaded part replaceable threading tool of the present invention, the convex part and the concave part may each have a conical shape including a truncated cone, but the convex part and the concave part May each have a pyramid shape including a truncated pyramid, and in this way, a plurality of independent protrusions can be ground at a time by linear movement of a rotating grindstone, so The convex portion can be easily processed.

  Further, in the threaded part replaceable threading tool of the present invention, the plurality of independent recesses may be, for example, an electrolytically processed part formed by electrolytic processing, but the plurality of independent recesses are It may be a die forming part formed of a die such as a press die or a sintered die, and in this way, processing of a plurality of recesses independent from each other can be performed easily with high accuracy and efficiency. Can do.

  And according to the manufacturing method of the threading part exchange type threading tool of the present invention, when the plurality of independent recesses are used as the shaping process part, at least a part of the plurality of protrusions of the fitting structure Using a die such as a press die or a sintered die with matching convex portions, the multiple concave portions of the fitting structure are molded so that multiple independent concave portions can be easily processed with high accuracy. And can be performed efficiently.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Here, FIG. 1 is a side view showing an entire threaded portion replaceable cutting tap as an embodiment of the threaded portion replaceable threading tool of the present invention in an assembled state, and FIG. 2 is a screw of the embodiment. FIG. 5 is an exploded view showing a machined part exchanging type cutting tap with a part of a threaded part taken as a cross section and omitting an end on the shank part side.

  3A, 3B, 3C, and 3D are a side view, a rear view, and a perspective view seen from the back side, showing the threaded portion of the threaded portion replaceable cutting tap of the above embodiment. FIG. 4 is an enlarged view showing a part of the end face shown in the perspective view, and FIGS. 4A, 4B, and 4C show the shank portion of the threaded portion replaceable cutting tap of the above embodiment. FIG. 5 is an enlarged view showing an enlarged part of the end face shown in the front view, FIG. 5 is a drawing showing a number of recesses in the threaded portion shown in FIG. 3 and a number of shank portions shown in FIG. FIG. 6 is an enlarged cross-sectional view showing a fitting state with the convex portion, and FIG. 6 is a diagram of the manufacturing method of the threaded portion replaceable threading tool of the present invention for forming a large number of concave portions of the threaded portion shown in FIG. It is a perspective view which shows the punch for press processing used for one Example, and the code | symbol 1 in the figure is a thread processing part exchange type of the said Example It shows the cutting tap.

  As shown in FIG. 1 to FIG. 4, the threaded part replaceable cutting tap 1 of the present embodiment includes a threaded part 2 and a shank part 3, and the threaded part 2 has, for example, five spiral shapes. Each of which has a spiral cutting edge 2a having a thread and is formed along each of the chip discharging grooves, and the shank portion 3 is formed by five spiral chip discharging grooves of the threaded portion 2. Each has five spiral-shaped chip discharge grooves 3a that are continuous with each other.

  In the threaded part replaceable cutting tap 1 of this embodiment, the threaded part 2 is connected to the shank part 3, the screw hole 2 b formed on the central axis of the threaded part 2 constituting the coupling structure, and the shank part 3. And a female screw hole 3b formed on the center axis of the front end portion (left end portion in FIGS. 1 and 2) and a screw hole 2b of the threaded portion 2 to be fastened to the female screw hole 3b of the shank portion 3. And a bolt 4 having a male threaded portion 4a. The bolt 4 has a head portion of the bolt 4 and a threaded hole 2b of the threaded portion 2 each having a conical tapered surface 4b, 2c. The tapered surfaces 4b and 2c are provided in close contact with each other with a high pressing force by the wedge effect to prevent the bolt 4 from loosening.

  Further, in the threaded part exchangeable cutting tap 1 of the present embodiment, the threaded part 2 and the shank part 3 constitute end fitting surfaces 2d and 3c of the threaded part 2 and the shank part 3 that constitute a fitting structure. A plurality of mutually independent recesses 2e and a plurality of mutually independent protrusions 3d are closely fitted to each other so that they are mutually perpendicular to the center axis and perpendicular to each other. Positioned with respect to direction.

  Here, as shown in FIG. 3, the multiple recessed portions 2 e of the threaded portion 2 each have a truncated quadrangular pyramid shape, are aligned at equal intervals in the vertical and horizontal directions on the end surface 2 d, and the multiple shank portions 3. As shown in FIG. 4, each of the convex portions 3d also has a truncated quadrangular pyramid shape, and is aligned at equal intervals in the vertical and horizontal directions on the end surface 3c. As shown in FIG. 5, the cross-sectional shape of the protrusion 3d is the same as the interval, and is complementary to the cross-sectional shape of the recess 2e. Thereby, the large number of concave portions 2e of the threaded portion 2 and the large number of convex portions 3d of the shank portion 3 can be closely fitted to each other between the flank surfaces 2f and 3e.

  In the threaded part replaceable cutting tap 1 of the present embodiment, the threaded part 2 is formed of a sintered material such as tool steel or high-speed tool steel, cemented carbide or diamond, while the shank part 3 is For example, it is formed of an inexpensive steel material that can have a heat treatment hardness of 56 HRC or higher.

  In addition, the dimensions of each concave portion 2e of the threaded portion 2 and each convex portion 3d of the shank portion 3 are the land widths of the end faces 2d and 3c (between the chip discharge groove of the cutting tap and the small diameter portion of the raised tap). The width of the flat portion extending radially from the center of the tap) is selected according to the threaded portion 2 and the shank portion 3 even when the land width is relatively narrow like the cutting tap 1 of the present embodiment. It can be firmly positioned and fixed so as not to rotate. In this embodiment, the dimensions are set so that the respective pitches of the concave portion 2e and the convex portion 3d are 2 mm, so that it can withstand a processing torque of 2.5 times or more of a normal female thread processing torque. Can do.

  And the shape of each recessed part 2e of the thread processing part 2 and each convex part 3d of the shank part 3 is based on the quadrangular pyramid of the range of apex angle 40 degree-60 degree | times, for example. In the present embodiment, the shape of each concave portion 2e and each convex portion 3d is set to a truncated quadrangular pyramid having an apex angle of 45 degrees.

  A large number of convex portions 3d of the shank portion 3 are, for example, a grinding machine, and a disc-shaped rotating grindstone having an outer peripheral end portion having an apex angle of 45 degrees is linear in two directions orthogonal to each other along the end surface 3c of the shank portion 3. And the pitch of the feed can be easily formed by making it equal to the pitch of the convex portions 3d. Further, in the manufacturing method of the present embodiment, a large number of recesses 2e of the threaded portion 2 are formed on the front end surface of the press working punch 5 in the same manner as described above, as shown in FIG. A large number of convex portions 5a having the same shape and the same pitch as the convex portions 3d are formed, and the punching punch 5 is pressed against the threaded portion 2 with an ordinary press machine. The convex portion 5 a is pushed into the end surface 2 d of the threaded portion 2. As a result, a large number of the recesses 2e independent of each other can be easily formed with high accuracy.

  In the threaded part exchangeable cutting tap 1 of this embodiment, the end face 3c that is one of the end faces 3c, 2d of the shank part 3 and the threaded part 2 that constitute the fitting structure is opposed to each other. And a plurality of independent protrusions 3d provided on the end face 2d, which is the other of the opposite end faces 3c and 2d of the shank part 3 and the threaded part 2, respectively. The recesses 2e closely fit with each other to position the shank portion 3 and the threaded portion 2 with each other, and in this positioning state, the bolt 4 constituting the coupling structure is fastened to the female screw hole 3b. The shank part 3 and the threaded part 2 are detachably coupled.

  Therefore, according to the threaded part replacement type cutting tap 1 of the present embodiment, a large number of protrusions 3d and a large number of recesses 2e, which are independent from each other, are closely fitted to each other. Since the mutual positioning in the rotation direction around the central axis and the mutual positioning in the direction crossing the central axis are performed, there is no need to perform positioning in the coupling structure. With respect to the screw hole 2b, the female screw hole 3b, and the like, it is possible to eliminate the need for strict processing accuracy, and it is possible to easily process the coupling structure and thus manufacture the cutting tap 1.

  Moreover, according to the threaded part exchangeable cutting tap 1 of the present embodiment, the shank part 3 and the threaded part 2 are made of different materials, and the threaded part 2 is made of a material having higher hardness than the shank part 3. Therefore, since the threaded portion 2 is less likely to be worn or chipped with repeated use of the tool, the number of replacements of the threaded portion 2 can be reduced.

  In addition, according to the threaded part replaceable cutting tap 1 of the present embodiment, each of the convex part 3d and the concave part 2e has a truncated pyramid shape. As described above, since the grinding can be performed at once by the linear movement of the rotating grindstone, it is possible to easily process the plurality of convex portions 3d independent of each other.

  Furthermore, according to the threaded part replaceable cutting tap 1 of the present embodiment, a large number of independent recesses 2e are formed by a large number of convex parts 5a on the front end surface of a press working punch 5 as a press die. Since it is a molding process part, the process of these many recessed parts 2e mutually independent can be performed easily with high precision and efficiently.

  And according to the manufacturing method of the thread processing part exchange-type cutting tap of a present Example, when many recessed parts 2e mutually independent are used as a shaping | molding process part, it corresponds with the whole many convex parts 3d of a fitting structure. Since the press working punch 5 having a large number of convex portions 5a including a portion is used to mold a large number of concave portions 2e of the fitting structure, it is possible to easily process a large number of independent concave portions 2e with high accuracy. And can be performed efficiently.

  As mentioned above, although demonstrated based on the example of illustration, this invention is not limited to the above-mentioned example, For example, if the threading part 2 may be replaced | exchanged frequently, the shank part 3 and the threading part 2 will be described. The materials may be the same as each other, and one or both of the multiple independent recesses 2e and the multiple independent projections 3d may be formed by electrical discharge machining or sintering. And the shape of these many recessed parts 2e and many convex parts 3d may be polygonal pyramids, such as a hexagonal pyramid other than a square, and a cone.

  Further, the fitting structure may be one in which a large number of convex portions are provided in the threaded portion 2 while a large number of concave portions are provided in the shank portion 3, and there are at least two independent convex portions and independent concave portions. It ’s fine. The coupling structure may be a structure in which the threaded portion 2 is fixed to the shank portion 3 with a shaft passing through the center of the shank portion 3.

  And the threading part exchange type threading tool of the present invention is not limited to the spiral groove type cutting tap of the above embodiment, but a threading tool such as a spiral point groove type cutting tap, a straight groove type cutting tap, a rising tap, a threading milling cutter, etc. It can also be applied to.

  Thus, according to the threaded part replaceable threading tool of the present invention, in the fitting structure, a plurality of independent convex parts and a plurality of concave parts are closely fitted, and the rotational direction around the central axis is Since mutual positioning and mutual positioning in the direction intersecting with the central axis are performed, there is no need to perform positioning with the coupling structure, so strict machining accuracy is required for members and parts constituting the coupling structure such as screw structures. It can be made unnecessary, and the machining of the joint structure and thus the manufacture of the tool can be facilitated.

  In addition, since the threaded part and the shank part can be separated, the reuse of the shank part and the resource recycling of the threaded part can be facilitated, and the threaded part can be manufactured to the minimum required length. Since the overall length can be shortened compared to the conventional integrated product, the amount of expensive material used in the threaded part can be reduced, the threading tool can be made cheaper, and the metal resources can be saved. You can also.

  Furthermore, in the case of deep hole machining, the shank portion can be replaced with a long one, and an inexpensive material can be used for the shank portion, so that the tool can be made inexpensive in this respect as well. Since the threaded portion can be exchanged, it can be a replaceable blade type that has a plurality of threaded portions for one shank portion and does not require re-polishing, and can contribute to resource saving.

  Furthermore, in the past, when an excessive torque was generated during screw machining, the screw hole was often damaged and the workpiece could not be used. However, according to the screw machining tool of the present invention, the tensile strength of, for example, the bolt of the coupling structure By adjusting the etc., if excessive torque is generated during threading, the fitting structure between the threaded part and the shank part can be removed and the shank part can be slipped between the threaded part and screw holes. Can prevent the workpiece from becoming unusable due to damage.

  And according to the manufacturing method of the threading part exchange type threading tool of the present invention, when a plurality of mutually independent concave parts are used as a die forming part, it coincides with at least a part of the convex parts of the fitting structure. Using a mold such as a press mold or a sintered mold having a convex part, the plurality of concave parts of the fitting structure are molded so that processing of the plurality of concave parts independent of each other can be easily performed with high accuracy. Can be done efficiently.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view showing an entire threaded portion replaceable cutting tap as an embodiment of the threaded portion replaceable threading tool of the present invention in an assembled state. It is an exploded view which abbreviate | omits the edge part by the side of a shank part while making a part of screw processing part into a cross section, and the threaded part exchange type cutting tap of the said Example. (A), (b), (c) and (d) are a side view, a rear view, a perspective view seen from the back side and a perspective view showing a threaded portion of the threaded portion replaceable cutting tap of the above embodiment, and It is an enlarged view which expands and shows a part of end surface shown in a perspective view. (A), (b) and (c) expand and show a part of end surface shown in the front view which shows the shank part of the threading part exchangeable cutting tap of the said Example, a side view, and the front view. It is an enlarged view. It is an expanded sectional view which shows the fitting state of many recessed parts of the thread process part shown in FIG. 3, and many convex parts of the shank part shown in FIG. It is a perspective view which shows the punch for press work used for one Example of the manufacturing method of the threading part exchange-type threading tool of this invention for formation of many recessed parts of the threading part shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Thread processing part exchange-type cutting tap 2 Thread processing part 2a Cutting edge 2b Screw hole 2c Tapered surface 2d End surface 2e Recessed part 2f Flank surface 3 Shank part 3a Chip discharge groove 3b Female thread hole 3c End surface 3d Convex part 3e Frank surface 4 Bolt 4a Male thread portion 4b Tapered surface 5 Punch for pressing 5a Convex portion

Claims (5)

Shank part,
A threaded portion separably coupled to the shank portion;
A coupling structure that separably couples the shank portion and the threaded portion;
A fitting structure for positioning the shank part and the threaded part with each other;
With
The fitting structure is
A plurality of independent convex portions provided on one of the end faces of the shank portion and the threaded portion facing each other;
A plurality of independent recesses, which are provided on the other of the end faces of the shank portion and the threaded portion facing each other, and which are closely fitted to the plurality of projections, respectively,
A threading part exchangeable threading tool comprising:   The threaded part exchangeable threading tool according to claim 1, wherein the shank part and the threaded part are made of different materials.   The threaded part replaceable threading tool according to claim 1 or 2, wherein each of the convex part and the concave part has a pyramid shape.   The threaded part replacement type threading tool according to any one of claims 1 to 3, wherein the plurality of independent recesses are mold forming parts.   5. The threaded part replaceable screw according to claim 4, wherein the plurality of recesses of the fitting structure are molded using a mold having a convex part that coincides with at least a part of the plurality of convex parts of the fitting structure. Manufacturing method of a processing tool.

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