JP2007044746A - Wire drawing die - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wire drawing die capable of enhancing strength of a die member, and considerably reducing occurrence of fatigue damage, cracks or the like. <P>SOLUTION: The wire drawing die 10 comprises a die member 14 and an annular member 16a. A die hole 22 for passing through a metallic wire 12 is formed in the die member 14. The annular member 16a is abutted on the outer circumferential surface 14a of the die member 14 along the center axis X. The annular member 16a is fastened and fixed to the die member 14 by the shrinkage fitting to the die member 14. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a drawing die for drawing a metal wire.

Conventionally, as a wire drawing die for drawing a metal wire, a diamond as a die member in which a die hole through which the metal wire is inserted is held by the sintered metal, and further, a sintered metal holding the diamond is used. What was fixed to the case was known (for example, patent document 1).
JP 2002-102917 A

  The conventional wire drawing die described in Patent Document 1 has a problem that fatigue damage, cracking, and the like occur in the die member due to pressure applied to the die member from the wire during wire drawing. Therefore, conventionally, by changing the shape and composition of the die member, the strength of the die member is improved, and fatigue damage and cracking of the die member are reduced.

  However, it is not easy to change the shape and composition of the die member because it takes a lot of labor, time and cost, and it is difficult to sufficiently reduce the occurrence of fatigue damage and cracking of the die member. .

  An object of the present invention is to provide a wire drawing die capable of further improving the strength of a die member and extremely reducing the occurrence of fatigue damage, cracking, and the like.

  The wire drawing die according to the present invention includes a die member in which a die hole into which a metal wire is inserted is formed, and a first annular member provided in contact with the outer peripheral surface of the die member along the center axis of the die hole. The first annular member is characterized in that it is fastened and fixed to the die member by any one of shrinkage, press fitting and caulking to the die member.

  In the wire drawing die according to the present invention, the first annular member applies pressure to the die member by tightening the die member from the outside. Therefore, a sufficiently large compressive stress is generated in the die member inward, and the pressure applied to the die member outward can be overcome when the metal wire is inserted. As a result, the strength of the die member can be further improved, and fatigue damage and cracking of the die member can be extremely reduced.

  Moreover, it is preferable that the 1st annular member has the 1st collar part contact | abutted on the outer surface of the die member extended in the direction which cross | intersects a center axis | shaft on the insertion side of a die hole. If it does in this way, since the force applied to an insertion direction with respect to a die member at the time of insertion of a metal wire can be received by the 1st collar part, the intensity as the whole wire drawing die can be raised.

  Moreover, it is preferable that the 1st annular member has a 2nd collar part contact | abutted to the outer surface of the die member extended in the direction which crosses a center axis | shaft on the insertion side to a die hole. In this case, even when the metal wire is cut when the metal wire is drawn, a force (also referred to as rear tension or back tension) applied to the die member in the direction opposite to the insertion direction is applied to the second flange portion. Therefore, the strength of the wire drawing die as a whole can be further improved.

  Moreover, it is preferable to provide further the 2nd annular member which is provided in the outer side of the 1st annular member and clamps the 1st annular member and the die member. In this case, since the plurality of annular members apply pressure to the die member, the strength of the die member can be further improved.

  ADVANTAGE OF THE INVENTION According to this invention, the further improvement of the intensity | strength of a die member can be aimed at and the die | dye for wire drawing which can reduce generation | occurrence | production of fatigue damage, a crack, etc. very much can be provided.

  Preferred embodiments of the present invention will be described with reference to the drawings. In the description, the same reference numerals are used for the same elements or elements having the same function, and a duplicate description is omitted.

  With reference to FIG. 1, the structure of the wire drawing die 10 according to the present embodiment will be described. FIG. 1 is a side view showing a cross-sectional configuration and a peripheral configuration of a wire drawing die according to the present embodiment.

  The wire drawing die 10 is a tool for drawing the metal wire 12. For this purpose, the wire drawing die 10 includes a die member 14, annular members 16 a to 16 d, a holding case 18, and a lid 20.

  The outer shape of the die member 14 has a substantially cylindrical shape. A die hole 22 for inserting the metal wire 12 is formed in the die member 14. The die hole 22 has an introduction portion 22a (generally referred to as an approach portion and a reduction portion) whose diameter gradually decreases as it moves away from an opening having a diameter larger than the wire diameter of the metal wire 12 to be inserted. One end is integrally formed on the side opposite to the opening of the introduction portion 22a, and the wire drawing portion 22b has a diameter smaller than the wire diameter of the inserted metal wire 12 (generally called a bearing portion). And an outlet portion 22c (generally referred to as a back relief portion and an exit portion) that is formed integrally with the other end of the wire drawing portion 22b and gradually increases in diameter as it is away from the other end of the wire drawing portion 22b. have. Thereby, in the die member 14, the diameter of the metal wire 12 is gradually reduced by the introduction portion 22a, and the wire diameter of the metal wire 12 is determined by the wire drawing portion 22b. As the die member 14, a diamond sintered body (PCD: Polycrystalline Diamond), a cemented carbide, a single crystal diamond (for example, natural diamond, synthetic diamond), SKD steel, or the like can be used.

  The annular member 16a is a first annular member in the present invention and has a cylindrical shape. The annular member 16 a is provided so that its inner peripheral surface abuts on the outer peripheral surface 14 a of the die member 14 along the central axis X of the die hole 22. Each of the annular members 16b and 16c is a second annular member in the present invention, and has a cup shape with a substantially U-shaped side cross section that is recessed in a shape corresponding to each of the annular members 16a and 16b. In other words, the annular member 16 b has a flange 24 that contacts the outer surface 14 b of the die member 14 that is on the insertion side of the die hole 22 and intersects the central axis X. On the other hand, the annular member 16 c has a flange portion 26 that is in contact with the outer side surface 14 c of the die member 14 on the insertion side of the die hole 22. The annular member 16d is the second annular member in the present invention and has a cylindrical shape. Each of the annular members 16b to 16d is provided such that its inner peripheral surface comes into contact with the outer peripheral surfaces of the respective annular members 16a to 16c along the central axis X.

  In the present embodiment, each of the annular members 16a to 16d is fastened and fastened to the die member 14 and each of the annular members 16a to 16c by being shrinked (details will be described later). Thereby, each annular member 16a-16 is giving the pressure to the direction which goes to the central axis X with respect to the die member 14. FIG. In addition, as each annular member 16a-16d, although hard materials, such as a cemented carbide alloy, a cermet, and a nickel-type alloy, and stainless steel can be used, for example, it is not restricted to this, It heat-heated to some extent and was cooled. Materials that sometimes shrink can also be used as appropriate.

  The holding case 18 has a cup shape with a substantially U-shaped side section that is recessed in a shape corresponding to the outer shape of the annular member 16d. The holding case 18 holds the die member 14 and the annular members 16 a to 16 d together with the lid body 20. The holding case 18 and the lid 20 are made of, for example, stainless steel.

  Next, a method for manufacturing the wire drawing die 10 having the above-described structure will be described.

  With reference to FIG. 2, the method of manufacturing the wire drawing die 10 by shrinking will be described. First, the dice member 14, each annular member 16a-16d, the holding case 18, and the cover body 20 are prepared. Each of the annular members 16a to 16d has an inner diameter smaller than the outer diameter of the die member 14 and each of the annular members 16a to 16c, and has a tight margin.

  Next, the annular member 16a is heated to thermally expand until the inner diameter of the annular member 16a becomes slightly larger than the outer diameter of the die member 14. Then, the thermally expanded annular member 16a is inserted into the die member 14, and the annular member 16a is cooled. As a result, the die member 14 is fastened to the extent that the annular member 16a is tightened, and pressure is applied to the die member 14 in the direction of the central axis X.

  Subsequently, the annular members 16b to 16d are also thermally expanded until the inner diameter of the insertion-side member is slightly larger than the outer diameter of the insertion-side member, and the insertion-side member is inserted into the insertion-side member. Thereby, each annular member 16b-16d will clamp | tighten each annular member 16a-16c, and will apply a pressure to the center axis | shaft X direction with respect to the die member 14. FIG.

  Subsequently, a die hole 22 having a predetermined shape for inserting the metal wire 12 into the die member 14 is formed by drilling through the die member 14, the flange portion 24, and the flange portion 26. Then, after the die member 14 and the annular members 16a to 16d that are fastened to each other are accommodated in the holding case 18, the lid body 20 is joined by welding or brazing to form the wire drawing die 10.

  As described above, in the present embodiment, the annular members 16a to 16d tighten the die member 14 from the outside to apply pressure to the die member 14. Thereby, a sufficiently large compressive stress is generated in the die member 14 in an inward direction, and the pressure applied to the die member 14 in the outward direction when the metal wire 12 is inserted can be overcome. As a result, the strength of the die member 14 can be further improved, and fatigue damage and cracking of the die member 14 can be extremely reduced.

  Further, in the present embodiment, the annular member 16 b has a flange portion 24 that is in contact with the outer surface 14 b of the die member 14 on the insertion side of the die hole 22. Thereby, since the collar part 24 receives the force applied to the die member 14 in the insertion direction when the metal wire 12 is inserted, the strength of the wire drawing die 10 as a whole can be improved.

  Moreover, in this embodiment, the annular member 16c has the collar part 26 which contact | abuts on the insertion side of the die hole 22, and the outer surface 14c of a die member. Thereby, even if the metal wire 12 is cut when the metal wire 12 is drawn, the collar portion 26 receives the back tension applied to the die member 14, so that the strength of the wire drawing die 10 as a whole is increased. It can be improved further.

  Here, in order to confirm that the strength of the die member 14 in the wire drawing die 10 according to the present embodiment was improved, the following test was performed.

  First, a cylindrical die member 14 made of PCD and a cylindrical annular member 16a made of stainless steel are prepared, and the annular member 16a is heated to about 550 ° C. and fixed to the die member 14 by shrinkage. did. Here, the die member 14 is set to have an outer diameter of 3.13 mm and a thickness of 1.5 mm. The annular member 16a has an outer diameter of 19 mm, an inner diameter of 3.1 mm, and an interference margin of 0.03 mm. Thereafter, a die hole 22 was formed in the die member 14 and processed so that the minimum diameter in the wire drawing portion 22b was 1.5 mm and the taper angle on the introduction portion 22a side was 14 °.

  On the other hand, for comparison, only the die member 14 having the same size, shape, and material as above and having the same size and shape as the above was prepared.

  As a test, a cone-shaped pin made of a cemented carbide with a taper angle of 14 ° was pushed into the die hole 22 formed in each of the prepared die members 14, and the die member 14 was destroyed. By measuring the load, the strength of the die member 14 when the simulated metal wire 12 was drawn was confirmed.

  As a test result, the load at the time of destruction of the die member 14 was 588 N when only the die member 14 was used, but was 1764 N when the annular member 16 a was fastened to the die member 14. Accordingly, when the die member 14 is fastened and fixed by the annular member 16a, the die member 14 can withstand about three times as much load as the case where the die member 14 is not fastened and fixed. It was confirmed that the strength was extremely improved.

  The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to the above-described embodiments, and various modifications can be made. For example, in the present embodiment, the wire drawing die 10 includes four annular members 16a to 16d. However, as illustrated in FIG. 3A, the wire drawing die 10 includes only one cylindrical annular member 28. Alternatively, two cylindrical annular members 28 may be provided as shown in FIG. Further, as shown in FIG. 3C, a cup-shaped cup having a flange portion 30 a on one outer surface side of the die member 14 and recessed in a shape corresponding to the die member 14. Only one annular member 30 may be provided, and as shown in FIG. 3D, the cup-shaped annular member 30 is provided so that the flange portions 30 a are on the same outer surface side of the die member 14. May be. Further, as shown in FIG. 3E, a cylindrical annular member 28 and a cup-shaped annular member 30 may be provided in combination, and a cup-shaped annular member 28 may be provided as shown in FIG. The annular member 30 may be provided on the die member 14 so as to face each other, and the force and the back tension applied in the insertion direction of the metal wire 12 may be received. Further, as shown in FIG. 3 (g), a ring-shaped annular member 32 may be provided so as to be arranged in the insertion direction of the metal wire 12, and the outer peripheral surface of the annular member is provided with unevenness or the like. It may be a shape. Further, various combinations of the above annular members can be used.

  In the present embodiment, the annular members 16a to 16d are fastened to the die member 14 and the annular members 16a to 16d by shrinkage, but the present invention is not limited to this. In other words, the die member 14 and the annular members 16a to 16c may be sequentially press-fitted into the annular members 16a to 16d to be fastened. Further, as will be described in detail later, each of the annular members 16a to 16d may be fastened by caulking the die member 14 and each of the annular members 16a to 16c. Furthermore, the annular members 16a to 16d can be fastened to the die member 14 and the annular members 16a to 16c, respectively, by using a combination of the shrinkage, press fitting, and caulking.

  Here, with reference to FIG. 4, a method of manufacturing the wire drawing die 10 by caulking will be described. FIG. 4 is a diagram showing a manufacturing process in the case of manufacturing a wire drawing die by caulking.

  First, an annular member 34 having a fitting portion 34a whose inner diameter is substantially the same as the outer diameter of the die member 14 and whose outer peripheral surface is processed so as to be fitted to the jig 36 is prepared. It inserts in the member 14 (refer Fig.4 (a)). Subsequently, the jig 36 is fitted into the fitting portion 34a of the annular member 34, and the annular member 34 is fastened to the die member 14 (see FIG. 4B). At this time, since the annular member 34 is plastically deformed, the annular member 34 is fastened to the die member 14 and pressure can be applied to the die member 14. Subsequently, the fitting portion 34a of the annular member 34 is scraped to adjust the shape of the annular member 34 (see FIG. 4C). When the annular member 34 is fastened to the die member 14 by caulking, a material that is plastically deformed such as stainless steel can be used as the annular member 34.

  Moreover, in this embodiment, although single-piece | unit objects, such as PCD, a cemented carbide alloy, a single crystal diamond, or SKD steel, are used as the die member 14, it is not restricted to these. That is, as shown in FIG. 5A, the die member 14 surrounds the base 38 on which the die hole 22 is formed, and the outer peripheral surface of the base 38, and prevents the base 38 from being damaged when the die hole 22 is formed. The ring-shaped reinforcing member 40 may be formed. At this time, PCD, cemented carbide, single crystal diamond, SKD steel, or the like can be used as the substrate 38, and cemented carbide, stainless steel, or the like can be used as the reinforcing member 40. Further, as shown in FIG. 5B, the reinforcing member 40 may be cup-shaped. Further, as shown in FIG. 5C, even if a sintered metal 42 is provided around the reinforcing member 40 in order to further prevent the base 38 from being damaged when the die hole 22 is formed. Good.

  Further, the shape of the annular members 16a to 16d is not particularly limited, and the inner peripheral surface or the outer peripheral surface viewed from the central axis X can be used as long as the die member 14 and the annular members 16a to 16d are fastened. Can be various shapes such as a substantially circular shape, a substantially hexagonal shape, and a substantially octagonal shape.

  Further, in the present embodiment, the metal wire 12 is drawn with the wire drawing die 10, but the present invention can also be applied when the tube material is drawn.

It is a side view which shows the cross-sectional structure of the drawing die | dye which concerns on this embodiment, and its periphery structure. It is a disassembled perspective view of the die for wire drawing concerning this embodiment. It is a side view which shows a part of cross-sectional structure of the various dice | dies for wire drawing which concern on a modification. It is a figure which shows the manufacturing process in the case of manufacturing the die for wire drawing by crimping. It is a side view which shows the cross-sectional structure of the die member applicable to this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Die for wire drawing, 12 ... Metal wire, 14 ... Die member, 16a-16d ... Ring member, 18 ... Holding case, 22 ... Die hole.

Claims (4)

A die member formed with a die hole through which the metal wire is inserted;
A first annular member provided in contact with the outer peripheral surface of the die member along the central axis of the die hole;
The wire drawing die, wherein the first annular member is fastened and fixed to the die member by any one of shrinkage, press fitting, and caulking with respect to the die member.   The first annular member has a first flange portion that comes into contact with an outer surface of the die member that extends in a direction intersecting the central axis on the insertion side of the die hole. The wire drawing die according to claim 1.   The first annular member has a second flange portion that comes into contact with an outer surface of the die member extending in a direction intersecting with the central axis on the insertion side into the die hole. The wire drawing die according to claim 1 or 2.   The second annular member that is provided outside the first annular member and that clamps the first annular member and the die member is further provided. Wire drawing dies.

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