JP6637094B2 - dice - Google Patents

Description

  The present invention relates to a die.

  2. Description of the Related Art Conventionally, dice are disclosed in, for example, JP-A-8-291369 (Patent Document 1) and JP-A-2006-55925 (Patent Document 2).

JP-A-8-291369 JP 2006-55925 A

  The conventional dies have a problem that it is difficult to control the habit of the wire after drawing. Therefore, the present invention has been made to solve the above problem.

  A die according to one embodiment of the present invention includes, in order from the upstream side, a reduction, a cylindrical bearing, and a back relief. The length of the bearing is more than 0% and 30% or less of the inner diameter of the bearing. The area is more than 100% and less than 105% of the cross-sectional area of the bearing, the back relief angle is 2 ° or more and 6 ° or less, and the cross-sectional area of the reduction is more than 100% and less than 110% of the cross-sectional area of the bearing; Is 2 ° or more and 6 ° or less.

FIG. 2 is a front view of the dice according to the first embodiment. It is a schematic diagram of a slip type wire drawing machine provided with a stepped capstan roller. FIG. 7 is a schematic diagram of a non-slip type wire drawing machine according to a second embodiment. It is a figure which shows the wire after wire drawing.

[Description of Embodiment of the Present Invention]
(Embodiment 1)
As shown in FIG. 1, the wire drawing die 1 according to the first embodiment has a hole 1h. The die 1 has a bell 1a, an approach 1b, a reduction 1c, a bearing 1d, a back relief 1e, and an exit 1f in order from the upstream side.

  The bell 1a is located on the most upstream side of the hole 1h. The angle α of the side surface of the hole 1h that defines the bell 1a is a bell angle. The bell 1a corresponds to an inlet for a wire and a lubricant to be drawn.

  Approach 1b is provided downstream of bell 1a. At the boundary between the bell 1a and the approach 1b, the slope of the hole 1h may change continuously or may change discontinuously. The angle β of the side surface of the hole 1h that defines the approach 1b is the approach angle.

  The reduction 1c is provided downstream of the approach 1b. At the boundary between the approach 1b and the reduction 1c, the slope of the hole 1h may change continuously or may change discontinuously. The angle γ of the side surface of the hole 1h that defines the reduction 1c is the reduction angle.

  The bearing 1d is provided downstream of the reduction 1c. At the boundary between the reduction 1c and the bearing 1d, the inclination of the hole 1h may change continuously or may change discontinuously. The inner diameter D of the hole 1h that defines the bearing 1d is constant. The bearing 1d has a cylindrical shape. The bearing 1d is a portion having the smallest hole diameter in the hole 1h.

  The back relief 1e is provided downstream of the bearing 1d. At the boundary between the bearing 1d and the back relief 1e, the inclination of the hole 1h may change continuously or may change discontinuously. The angle θ of the side surface of the hole 1h that defines the back relief 1e is the back relief angle.

  The exit 1f is provided downstream of the back relief 1e. At the boundary between the bearing 1d and the back relief 1e, the inclination of the hole 1h may change continuously or may change discontinuously. The angle φ of the side surface of the hole 1h that defines the back relief 1e is the exit angle.

  Assuming that the inner diameter of the reduction 1c is RD, a relationship of D <RD ≦ 1.049D is established between RD and D. Therefore, the portion having the inner diameter RD in the above relationship is the reduction 1c. The cross-sectional area of the reduction 1c is more than 100% and 110% or less of the cross-sectional area of the bearing 1d.

  Assuming that the inner diameter of the back relief 1e is BD, a relationship of D <BD ≦ 1.025D is established between BD and D. Therefore, the portion having the inner diameter BD in the above relationship is the back relief 1e. The cross-sectional area of the back relief 1e is more than 100% and not more than 105% of the cross-sectional area of the bearing 1d.

  The length of the bearing 1d is L. A relationship of 0 <L ≦ 0.3D is established between L and D.

  In order to measure the shapes of the reduction 1c, the bearing 1d, and the back relief 1e, a transfer material (for example, Represet manufactured by Marumoto Struers Co., Ltd.) is filled in the hole 1h, and a replica in which the shape of the hole 1h is transferred is used. Make it. This replica is cut along a plane including the center line 1p to obtain a sectional view of the hole 1h such as the hole 1h in FIG. In the cross-sectional view, the cylindrical portion having the smallest inner diameter is referred to as a bearing 1d. In the cross-sectional view, a portion located adjacent to the bearing 1d and upstream of the bearing 1d and having an inner diameter RD satisfying D <RD ≦ 1.049D is defined as a reduction 1c. In the cross-sectional view, a portion located adjacent to the bearing 1d and downstream of the bearing 1d and having an inner diameter BD satisfying D <BD ≦ 1.025D is defined as a back relief 1e.

  In measuring the reduction angle γ, in the cross-sectional view of the hole 1h, tangents 12c, 13c are drawn on both side surfaces at the reference point 11c of the reduction 1c (where RD = 1.049D), and the angle formed by the two tangents 12c, 13c. Is the reduction angle γ.

  When measuring the back relief angle θ, in the cross-sectional view of the hole 1h, tangents 12e and 13e are drawn on both side surfaces at the reference point 11e of the back relief 1e (a portion where BD = 1.025D), and the two tangents 12e and 13e are drawn. The angle formed is the back relief angle θ.

  FIG. 2 is a schematic diagram of a slip type wire drawing machine provided with a stepped capstan roller. As shown in FIG. 2, a plurality of dies 9 are arranged in a slip-type wire drawing machine having stepped capstan rollers 101 and 102. The diameter of the bearing of each die 9 is set so that a predetermined cross-sectional area reduction rate is obtained for each pass of each die 9. The running speed of the wire 8 increases each time it passes through the die 9. Each of the steps of the stepped capstan rollers 101 and 102 is designed such that its peripheral speed is always faster than the traveling speed of the wire. This prevents the wire 8 from bending. Therefore, wire drawing is performed while slipping by a speed difference between the traveling speed of the wire 8 and the peripheral speed of the stepped capstan rollers 101 and 102. Since the wire is drawn while slipping, there is a problem that the surface of the wire 8 is scratched. The diameter of the wire 8 is determined by the inner diameter D of the bearing of the finishing die 1 which is the final pass. The precision (diameter of bearing, roundness) of the final finishing die 1 must be precisely controlled. When the die 1 described in the embodiment is used as a finishing die, its performance is maximized.

  The wire 8 is supplied from the supply bobbin 103 in a direction indicated by an arrow 111. The wire 8 is drawn by a die 9. The wire 8 is fed by the stepped capstan rollers 101 and 102. The stepped capstan rollers 101 and 102 rotate in the direction indicated by the arrow R1. The outer diameters of the stepped capstan rollers 101 and 102 become larger toward the downstream of the flow of the wire 8. This is because the cross-sectional area of the wire 8 becomes smaller toward the downstream, and the feed speed of the wire 8 increases. Finally, the wire 8 is wound on the winding bobbin 104. The wire 8 is used as a steel wire such as a steel cord for reinforcing tires and high-pressure hoses and a saw wire for slicing semiconductor ingots.

  The center line 1p of the die 1 is arranged at an angle k with respect to the wire 8. Since the center line 1p of the die 1 is inclined with respect to the wire 8, a habit (curved shape) can be formed in the wire 8. Thereby, it becomes easy to wind the wire 8 around the cylindrical winding bobbin 104. The inventor of the present invention has conducted intensive studies to impart an appropriate habit (curved shape) to the wire 8 even after drawing a long distance in the die 1. It has been found that the inclination can be imparted by tilting 1 with respect to the direction of the wire. Specifically, it has been found that, when used for wire drawing of 300 km or more, the problem can be solved only when the reduction angle, the back relief angle, and the bearing length are in specific ranges.

  The bearing length L needs to be more than 0% and 30% or less of the inner diameter D of the bearing. If the bearing length L exceeds 30% of the inner diameter D of the bearing 1d, the bearing 1d becomes too long, and the wire drawing resistance in the bearing 1d becomes large and heat is easily generated, so that the curl evaluation is deteriorated after long distance wire drawing. .

  The cross-sectional area of the back relief 1e is more than 100% and not more than 105% of the cross-sectional area of the bearing, and the back relief angle θ is 2 ° or more and 6 ° or less. If the back relief angle θ is less than 2 °, the back relief angle θ is too small, so that the back relief 1e functions in the same manner as the bearing 1d, so that the wire drawing resistance increases and heat is easily generated, and the curl evaluation deteriorates. When the back relief angle θ exceeds 6 °, it is necessary to increase the inclination angle k in order to impart curl, and the contact surface between the die 1 and the wire becomes unstable. For this reason, the curl evaluation is deteriorated after long distance drawing. The cross-sectional area of the reduction 1c is more than 100% of the cross-sectional area of the bearing 1d and 110% or less, and the reduction angle γ is 2 ° or more and 6 ° or less. When the reduction angle γ is less than 2 °, the reduction angle γ becomes too small, and the reduction 1c functions in the same manner as the bearing 1d, so that the wire drawing resistance increases and heat is easily generated. Getting worse. When the reduction angle γ exceeds 6 °, the reduction angle γ becomes large, so that the curl is given after the inner diameter changes abruptly in the reduction 1c, so that the quality of the wire after long distance drawing becomes unstable.

(Embodiment 2)
FIG. 3 is a schematic diagram of a non-slip type wire drawing machine according to the second embodiment. As shown in FIG. 3, the die 1 described in the first embodiment may be applied to a non-slip type wire drawing machine. A non-slip type wire drawing machine in which the dancer pulley 524, the die 9, and the capstan roller 521 are used as one wire drawing machine and a plurality of wire drawing machines are connected under synchronous control. Since the traveling speed of the wire 8 after passing through the die 9 is equal to the peripheral speed of the capstan rollers 521, 522 that come into contact next, no slip occurs between the wire 8 and the capstan rollers 521, 522. Since the dancer pulley 524 is rotatable in the direction indicated by the arrow, the distance between the supply bobbin 103, the capstan rollers 521, 522, and the bobbin 531 can be adjusted by the dancer pulley 524. As a result, it is possible to prevent the wire rod 8 from slipping with respect to the capstan rollers 521 and 522. In the final wire drawing, a habit is given by the die 1.

(Example 1)
Dice (D = 0.1 mm) indicated by sample numbers 1 to 5 in Table 1 were prepared. The material of the die is sintered diamond. The shape is shown in FIG.

  In Table 1, "bearing length (%)" refers to the ratio of the bearing length to the inner diameter D of the bearing. For example, "5" indicates that the bearing length is 0.05D.

  A brass-plated piano wire was drawn using the dies in Table 1 as the dies 1 in FIG. The outer diameter of the brass-plated piano wire after drawing is 0.1 mm, the outer diameter of the brass-plated piano wire before drawing with the die 1 is 0.105 mm, and the drawing speed after drawing is 500 m / min. The wire 8 after the drawing became a coil as shown in FIG. The drawn wire was cut out and placed on a surface plate, and the wire was drawn 1 km while adjusting the tilt angle (k in FIG. 2) so that the curl diameter d (FIG. 4) became 300 mm. Thereafter, the wire was further drawn for 300 km to perform curl evaluation. The curl diameter d was evaluated as “AA” when the curl diameter was 250 mm or more and 300 mm or less, “A” when 200 mm or more and less than 250 mm, and “B” when 150 mm or more and less than 200 mm.

  For Sample No. 1 having a back relief angle of 1 °, the curl evaluation was “B”. This is thought to be because the back relief angle is too small and the back relief acts in the same manner as the bearing, so that the wire drawing resistance increases and heat is easily generated, and the curl evaluation deteriorates. Further, when the angle of the back relief is small, the contact area between the wire and the side surface of the die hole increases, so that the wire drawing resistance increases and the wire is easily broken.

  Sample No. 5 having a back relief angle of 7 ° has a curl evaluation of “B”. This is considered to be because the back relief angle becomes large, and it is necessary to increase the inclination angle k in order to impart curl, and the contact surface between the die and the wire becomes unstable.

It has been found that the most preferable range of the back relief angle is 4 ° or more and 6 ° or less.
(Example 2)
In Example 2, a die was prepared in the same manner as in Example 1 except that the reduction angle was set to 4 °, and the curl was evaluated under the same drawing conditions. Table 2 shows the results.

From Table 2, the same tendency as in Example 1 was observed.
(Example 3)
In Example 3, a die was prepared in the same manner as in Example 1 except that the reduction angle was 6 °, and the curl was evaluated under the same drawing conditions. Table 3 shows the results.

From Table 3, the same tendency as in Example 1 was observed.
(Example 4)
In Example 4, a die was prepared in the same manner as in Example 1 except that the bearing length was changed to 10%, and the curl was evaluated under the same drawing conditions. Table 4 shows the results.

From Table 4, the same tendency as in Example 1 was observed.
(Example 5)
In Example 5, a die was prepared in the same manner as in Example 1 except that the bearing length was set to 20%, and the curl was evaluated under the same drawing conditions. Table 5 shows the results.

From Table 5, the same tendency as in Example 1 was observed.
(Example 6)
In Example 6, a die was prepared in the same manner as in Example 1 except that the bearing length was set to 30%, and the curl was evaluated under the same drawing conditions. Table 6 shows the results.

From Table 6, the same tendency as in Example 1 was observed.
(Example 7)
In Example 7, a die was prepared in the same manner as in Example 4 except that the reduction angle was 4 °, and the curling was evaluated under the same drawing conditions. Table 7 shows the results.

From Table 7, the same tendency as in Example 4 was observed.
(Example 8)
In Example 8, a die was prepared in the same manner as in Example 4 except that the reduction angle was 6 °, and the curl was evaluated under the same drawing conditions. Table 8 shows the results.

From Table 8, the same tendency as in Example 4 was observed.
(Example 9)
In Example 9, a die was prepared in the same manner as in Example 5 except that the reduction angle was 4 °, and the curl was evaluated under the same drawing conditions. Table 9 shows the results.

From Table 9, the same tendency as in Example 5 was observed.
(Example 10)
In Example 10, a die was prepared in the same manner as in Example 5 except that the reduction angle was set to 6 °, and the curl was evaluated under the same drawing conditions. Table 10 shows the results.

From Table 10, the same tendency as in Example 5 was observed.
(Example 11)
Dice (D = 0.1 mm) indicated by sample numbers 1101 to 1109 in Table 11 were prepared. The material of the die is a binderless nano-polycrystalline diamond containing no binder. The shape is shown in FIG.

  Curl was evaluated under the same drawing conditions as in Example 1. The outer diameter of the brass-plated piano wire after drawing is 0.1 mm, the outer diameter of the brass-plated piano wire before drawing with the die 1 is 0.105 mm, and the drawing speed after drawing is 500 m / min. Table 11 shows the results. Note that sample numbers 1103 and 1104 are the same as sample numbers 22 and 32.

  For sample numbers 1101, 1106, and 1107 having a reduction angle of 1 °, the curl evaluation is “B”. This is considered to be because the reduction angle is too small, the reduction works in the same manner as the bearing, and the wire drawing resistance increases, and heat is easily generated, so that the curl evaluation deteriorates.

  For sample numbers 1105, 1108, and 1109 having a reduction angle of 7 °, the curl evaluation is “B”. This is presumably because the reduction angle increases and the curl is applied after the inner diameter changes abruptly in the reduction, so that the quality of the wire becomes unstable.

(Example 12)
Dice (D = 0.1 mm) indicated by sample numbers 1201 to 1208 in Table 12 were prepared. The material of the die is a binderless nano-polycrystalline diamond containing no binder. The shape is shown in FIG.

  Curl was evaluated under the same drawing conditions as in Example 11. Table 12 shows the results. Note that sample numbers 1202, 1203 and 1204 are the same as sample numbers 2, 42 and 52.

  For sample numbers 1206, 1207, and 1208 having a bearing length of 35%, the curl evaluation is “B”. This is considered to be due to the fact that the bearing length is increased, the drawing resistance is increased, and heat is easily generated, so that the curl evaluation is deteriorated.

  It should be understood that the embodiments and examples disclosed this time are illustrative in all aspects and are not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the embodiments described above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  1,9 dice, 1a bell, 1b approach, 1c reduction, 1d bearing, 1e back relief, 1f exit, 1h hole, 1p center line, 8 wires, 11c, 11e Reference point, 12c, 12e, 13c, 13e tangent, 101 , 102 stepped capstan roller, 103 supply bobbin, 104 take-up bobbin, 521, 522 capstan roller, 524 dancer pulley.

Claims (2)

Reduction in order from the upstream side, a die hole is provided to chromatic bearings, and a back relief cylindrical,
The bearing length is more than 0% and 30% or less of the diameter D of the bearing;
In the cross-sectional view of the hole, two first tangents are drawn on both side surfaces at a portion where the diameter BD of the back relief is 1.025D, and an angle formed by the two first tangents is defined as a back relief angle;
A cross-sectional area of the back relief is more than 100% and 105% or less of a cross-sectional area of the bearing, and the back relief angle is 2 ° or more and 6 ° or less;
In the cross-sectional view of the hole, two second tangents are drawn on both side surfaces at a portion where the reduction diameter RD is 1.049D, and an angle formed by the two second tangents is defined as a reduction angle,
A die, wherein a cross-sectional area of the reduction is more than 100% and 110% or less of a cross-sectional area of the bearing, and the reduction angle is 2 ° or more and 6 ° or less.   The die according to claim 1, wherein the back relief angle is 4 ° or more and 6 ° or less.

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