JP2001079609A - Vibration drawing method of wire and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain large amplitude regardless of the wire diameter and to realize high drawability to a hard-to-work material whose diameter is small and surface is not treated by making half dies dividing a die axially symmetrically into two parts stand opposite to each other providing a clearance of not less than a specified value of the amplitude between the divided faces and vibrating the half dies in a direction toward the center axis while drawing a material out. SOLUTION: The divided faces of a pair of the half dies 2a, 2b are stood opposite to each other providing the clearance of >=2 times one-sided amplitude at the vibtationless time. To execute drawing, a wire W is connected to drawing force transmitting means by pressing through the divided faces of the half dies 2a, 2b and drawn out while vibrating the half dies 2a, 2b ultrasonically toward the center axis of the dies by operating both or one side of vibration generating means 3a, 3b. In such a case, the vibration system of the ultrasonic vibration to be imparted to the individual half die 2a, 2b is taken as a longitudinal vibration system. Then, the prevention of welding and great reduction of drawing resistance are realized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration drawing method and apparatus suitable for wires made of difficult-to-machine materials.

[0002]

2. Description of the Related Art Conventionally, a method using a hole die has been widely used as a method for drawing a wire. This method has the advantages of low cost and good processing accuracy, but difficult-to-process materials such as titanium and its alloys, tantalum, and intermetallic compounds, which are industrially high in value, have poor weldability. There is a problem that the wire cannot be pulled out because it is brittle and easily broken. As another method, a method using a roller die using a pair of grooved rolls facing each other is known. This method is disclosed in JP-A-10-3
No. 23712 has been proposed, in which frictional resistance generated at the time of drawing can be reduced and a large workability can be given, so that difficult-to-work materials such as titanium and its alloys, tantalum, and intermetallic compounds can be drawn to some extent. However, as described in the prior art, for example, titanium and its alloys cannot be extracted or difficult at a cross-sectional reduction rate of 3% or more, and the drawing force is not so small. There was a problem that it was not applicable.

As a countermeasure, a method using a radial ultrasonic vibrating dice is known. This method is to apply ultrasonic vibration in the radial direction to the die, and it is possible to obtain effects such as reduction of drawing resistance and prevention of material welding as compared with conventional drawing, and as a result, processing accuracy is improved,
Advantages such as chlorine-free and low viscosity of the drawing oil agent can be obtained. However, in this prior art, the primary short circular ring vibration system is used as a vibration system for ultrasonically vibrating the die in the radial direction, and thus, in principle, the amplitude changes substantially in proportion to the die diameter. Therefore, in particular, when the diameter of the drawn wire is small, for example, when the wire diameter is about 6 mm or less, there is a disadvantage that the above-described effect due to the ultrasonic vibration is reduced. Therefore, hard-to-draw wires such as titanium and its alloys and tantalum are usually pulled out by performing a surface treatment such as an oxide film or plating, so that pull-out is possible. However, there is a problem that it is necessary to remove the surface treatment film after the drawing, and the processing (for example, centerless polishing, pickling, shot blasting, etc.) requires a lot of labor and time.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to obtain a large amplitude irrespective of a wire diameter and to obtain a small-diameter wire. It is an object of the present invention to provide a vibration drawing method for a wire rod capable of realizing a high drawing property for a difficult-to-process material without a surface treatment. Another object of the present invention is to obtain a large amplitude irrespective of the wire diameter by a relatively simple structure,
It is an object of the present invention to provide a vibrating wire drawing apparatus for a wire rod which can realize a high drawing property for a difficult-to-machine material having a small diameter and no surface treatment.

[0005]

In order to achieve the above-mentioned object, the method of vibration drawing of a wire according to the present invention uses a dice which is divided into two parts symmetrically with respect to an axis, and the half dice is applied to a division plane with an amplitude of 2.
The basic feature is that half the dies are vibrated in the direction toward the central axis while pulling out the material while providing a clearance more than twice the clearance. The vibration includes both ultrasonic longitudinal vibration and low-frequency longitudinal vibration.

Further, the vibration drawing apparatus for a wire rod according to the present invention comprises a pair of half dies divided into two symmetrically in an axisymmetric manner, vibration generating means connecting the rear portions of the respective half dies, and the half dies. And a means for holding the divided surfaces facing each other so as to have a clearance of at least twice the amplitude. The vibration generating means includes an ultrasonic vibrator and a piezo element. In any of the methods, the cross-sectional shape of the half die is arbitrary, such as square or round. In the case of a round shape, it is preferable to use both an oval shape and a round shape, and to perform drawing by combining these two types of half dies alternately in a plurality of stages. It is preferable that the divided surfaces have a phase shift. Further, the present invention includes a case where the half die, the vibration generating means, and the holding means have means for rotating around a wire.

[0007]

According to the present invention, since the dice are axially symmetrically divided into two and the individual half dice are subjected to ultrasonic vibration or low frequency vibration in the direction toward the central axis, a large vibration amplitude can be obtained regardless of the wire diameter. According to this method, a vibration amplitude several times in principle can be obtained irrespective of the wire diameter as compared with the conventional radial ultrasonic vibration extraction method using a short circular vibration system, thereby making it possible to reduce the wire material. Since the working mechanism of tapping from the radial direction can be sufficiently exerted, adhesion due to friction between the die and the wire is prevented, and the above-described radial direction is used for drawing a difficult-to-work wire having a small diameter of 6 mm or less. The effect by the ultrasonic vibration can be obtained more strongly. When low-frequency vibration is used as the vibration type, it is possible to realize the same cost as a conventional hole die. Further, when ultrasonic vibration is used as the vibration type, the cost can be reduced to about the same as the conventional method using a short annular vibration system.

[0008]

Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 to 3 show a first embodiment of a method and an apparatus for vibration drawing of a wire according to the present invention. Reference numeral 1 denotes a vibrating dice device, which is provided with a pair of right and left mounting tools 11a and 11b on a die mounting body 10 having a guide hole for a wire W to be drawn with a drawing line interposed therebetween. Although not shown, the wire W is guided to a desired drawing force transmitting means such as a winding drum.

Reference numerals 2a and 2b denote a pair of half dies which are bisected in an axisymmetric manner. Since the half dies 2a and 2b have a square drawing cross section in this example, FIG.
As shown in (b), the approach portion 20, the bearing portion 21, and the relief portion 22, which form the division surface so that the cross section forms a square when combined, are each formed in a half-angle shape (triangular shape). The seating bolt hole 23 is formed in the mating surface 23 adjacent to the hole so as to reach the rear surface.
0, 230 are provided.

Reference numerals 3a and 3b denote vibration generating means. In this example, an electrostrictive ultrasonic vibrator is used, and female screw holes 301 are provided on the center lines of the end faces of the horns (boosters) 30a and 30b directly connected to the vibrating portion. The back of the half dies 2a and 2b are horns 30a and 30b
And is firmly fixed to the horns 30a, 30b by screws 9, 9 inserted into the seated bolt holes 230, 230. The respective vibration generating means 3a and 3b are connected to the respective or common ultrasonic oscillators 31 and
Both or one of them is caused to vibrate at a frequency selected from the range of 120 KHz. A suitable range for the frequency is typically 15-30 KHz. The reason is that at an ultrasonic frequency of 30 KHz or more, the amplitude becomes small and the force becomes weak. However, when the drawing finish cross section is very small, for example, 0.5 mm or less, the number of hits can be increased, and the ultrasonic vibrator becomes compact and the power consumption can be reduced. Is also good.

As shown in FIG. 3B, the divided surfaces of the pair of half dies 2a and 2b are 2a or more (a:
(One-sided amplitude) clearance C is provided.
The holding means for that purpose is optional, but in this example, the horns 30a, 30b of the vibration generating means 3a, 3b are provided with a collar 300, respectively, and the collars 300, 300 are mounted on the left and right fixing portions 11a, 11b. Fixture 11
0, 110 respectively.

To perform the drawing in the first embodiment, the wire W is connected to the drawing force transmitting means through the divided surfaces of the pair of half dies 2a and 2b facing each other with the clearance C as described above, and vibration is generated. Means 3a, 3b
Are operated, and the half dies 2a and 2b are pulled out toward the center axis of the dies while ultrasonically vibrating as shown in FIG. Both vibration generating means 3a,
The vibration drive by 3b preferably has the same phase.

In this case, the vibration system of the ultrasonic vibration applied to each half die 2a, 2b is a longitudinal vibration system. As described above, the half dies 2a and 2b are used, and the respective half dies 2a and 2b are ultrasonically vibrated in a direction toward the central axis, and the divided surfaces of the half dies 2a and 2b are aligned with the axis of the wire W. In principle, the amplitude a is not affected by the diameter of the die hole,
A large vibration amplitude can be obtained irrespective of the wire diameter, and the effect of preventing welding and reducing the drawing resistance can be obtained more strongly in drawing a difficult-to-work wire having a small diameter. In addition, the advantage that the amplitude several times higher than that of a short ring vibration system such as the conventional radial ultrasonic vibration extraction method can be obtained with less power consumption of about ５ is also obtained. In the drawing, the drawing is performed in one stage. However, it is needless to say that the drawing may be performed in multiple stages in the same manner as the round wire drawing described later according to the cross-section reduction rate. In that case, the half-die split surfaces of the adjacent stages may or may not be out of phase with each other.

FIGS. 4 to 8 show a second embodiment of the method and apparatus for vibration drawing of a wire according to the present invention. In the second embodiment, the present invention is applied to a round wire drawing, and basically, as shown in FIG. 4, the divided surfaces of the half dies 2a and 2b have a semicircular shape or a sectional shape similar thereto. . Also in this case, the half dies 2a and 2b
In the same manner as in the embodiment, the pair of vibration generating means 3a, 3b are in contact with the end faces of the horns 30a, 30b, and are provided with bolt holes 23 with seats.
The horn 30a,
It is firmly fixed to 30b. Then, the divided surfaces of the pair of half dies 2a and 2b are opposed to each other with a clearance C of 2a or more (a: one-sided amplitude) when there is no vibration as shown in FIG. Other configurations are the same as those of the above-described first embodiment, and a description thereof will not be repeated. This second aspect also,
A pair of confronting half dies 2 with clearance C
The wire W is connected to the pull-out force transmitting means through the divided surfaces of the a and 2b, and both or one of the vibration generating means 3a and 3b is operated, so that the half dies 2a and 2b are directed toward the center axis of the ultrasonic vibration. It is pulled out while making it.

However, when the drawing is performed with the single divided die shown in FIG. 4, it is undeniable that the roundness is reduced as compared with the method using the circular die. FIGS. 5 to 8 show a method and an apparatus for covering such inconvenience, in which at least two types of half dies having different division surface shapes are used, and a multi-stage drawing is performed by using the above-described vibration drawing. It is characterized by:

FIGS. 5 and 6 show an example in which four-stage drawing is performed. Four block-like mounting members 11a, 11b, 11c and 11d are arranged on a drawing device die mounting body 10 vertically and horizontally and screws and the like are used. And a common vibration horn 30a, 30b is arranged between the horizontal inner surfaces of the two pairs of mounting tools 11a, 11b and 11c, 11d on the left and right.
10 and 110 are fixed by being tightened with a tightening screw, and the tip of each of the vibration horns 30a and 30b is
Two sets of half dies 2a, 2b, 2a, 2b each of which is a pair for the first stage and the third stage are fixed by the method described above.

On the other hand, two pairs of upper and lower fixtures 11a, 11
A common vibration horn 30a ', 30b' is arranged between the vertical inner surfaces of c and 11b, 11d to fix fixtures 110, 110
Is fixed by tightening with a tightening screw. Then, two sets of half dies 2a ', 2b', 2a ', 2b' each consisting of a pair for the second stage and the fourth stage are provided at the tip of the vibration horns 30a ', 30b', respectively. It is fixed in such a way. The vibration horns 30a, 30b and 30a ', 30b' are respectively connected to vibration generating means (the left and right sides are omitted in FIG. 5). It is electrically connected to the sound wave oscillator 31.

The two sets of half dies 2a, 2b, 2a, 2b for the first stage and the third stage are located at an interval as shown in FIG. The half dies 2a 'and 2b' for the second stage are located between the half dies of
Two sets of half dies 2a 'and 2b' for the fourth stage are located immediately near the half dies 2a and 2b for the stage. FIG. 6 shows only one side of a pair of half dies. The pair of half dies 2a and 2b for the first stage and the third stage are designed so that the cross-sectional shape when combined is an oval shape as shown in FIG.
(A) Approach part 2 forming a division surface as in (b)
0, the bearing portion 21 and the relief portion 22 each have a semi-elliptical shape. The pair of half dies 2a 'and 2b' for the second and fourth stages form a split surface as shown in FIGS. 8 (a) and 8 (b) so that the cross-sectional shape when combined is a round shape. The bearing portion 21 and the relief portion 22 are each formed in a semicircular shape. Needless to say, the pair of half dies 2a, 2b, 2a ', 2b'
As shown in FIG. 7A and FIG. 8A, when the divided surfaces do not vibrate, they are opposed to each other with a clearance C of 2a or more (a: one-sided amplitude). The setting and holding of the clearance are performed by the fixtures 110 and 110.

The area reduction rate of the half dies from the first stage to the fourth stage may be appropriately set according to the material, thickness, mechanical characteristics, etc. of the wire. The vibration condition may be the same for the first and third stages and the second and fourth stages, or may be changed. The other configuration is the same as that of the above-described vibrating dice device of the first embodiment, and thus the description is omitted. Although four stages are shown in the figure, the present invention is not limited to this. However, at least two stages are required. In the drawing, the half dies of the first and third stages (oval shape drawing) vibrate in the vertical direction, and the half dies of the second and fourth stages (round shape drawing) lie in the horizontal direction. However, the present invention is not limited to this, and may be reversed. In this aspect, the first and third stages, and the second and fourth stages are shared horns for compactness and simplification of the device, and are connected to the vibration generating means, respectively. Independent horns and vibration generating means may be used. The phase shift of the half dies adjacent in the drawing direction is in principle 90 degrees, but this may not be the case if the number of drawing stages is large.

In performing the drawing in this embodiment, a pair of first to fourth half dies 2a, 4a, which are opposed to each other with a clearance C of the vibrating dice device 1 are used.
The wire W is connected to the pull-out force transmitting means through the divided surfaces of 2b, 2a ', and 2b', and both or one of the vibration generating means is operated to divide the half dies 2a, 2b, 2a ', 2
At least one side of b 'is pulled out while ultrasonically vibrating toward the center axis of the die.

Thus, in the first stage, the half dies 2a,
By pulling out the wire 2b toward the center axis of the die while ultrasonically oscillating, the wire W having a circular cross section is violently beaten from the radial direction and drawn into an oval cross section while receiving the effect of reducing the drawing resistance. Enter the steps, 90
The half dies 2a 'and 2b' out of phase are pulled out while ultrasonically oscillating toward the center axis of the dies, so that the wire W 'having an oval cross-section has a circular cross-section while receiving the effect of reducing the drawing resistance. Wire is drawn. Then, in the third stage, an oval-shaped half split die 2 is again formed.
The wire is drawn into an oval cross-sectional shape by ultrasonic vibration toward the center axis of the dies a and 2b.
Half round dice 2 from the direction where the phase is shifted
It is pulled out while receiving ultrasonic vibrations toward the center axes of the dies a ′ and 2b ′, and drawn into a circular cross-sectional shape. Therefore, pull-out resistance is drastically reduced overall, and conventional hole dies,
With a roller die and a short ring vibration die, a difficult-to-draw material can be drawn smoothly even under conditions of a high cross-sectional reduction rate such as disconnection.

From the viewpoint of efficiency, the continuous drawing as described above is preferable. However, in some cases, the sequential drawing for each stage may be performed. In this case, a plurality of individual vibrating dice devices are used, the first vibrating dice device is equipped with the above-mentioned oval-shaped half dice, and the second vibrating dice device is the above-described round-shaped half dice. Is mounted out of phase with the oval-shaped half-die. And
A winding means including a bobbin is arranged on the pull-out side of the first vibrating die apparatus, and the wire drawn into the oval cross-sectional shape is taken up. The bobbin thus taken up is attached to a supplier located upstream of the second vibrating die apparatus. In this case, the drawing may be performed by a drawing means (not shown).

FIG. 9 shows a third embodiment of the method and apparatus for vibration drawing of a wire according to the present invention. This third aspect is suitable for round wire drawing, that is, to improve the roundness by equalizing the influence of the divided surface of the half die, and to rotate the vibrating dice device including the die mounting body 10 by rotating a gear and a motor. Means 9 is to rotate at a required rotation speed N. The die mounting body 10 has a wire guide hole in the center, and fixtures 110, 110 are provided on one surface, and the horn 30 of the vibration generating means 3a, 3b.
a and 30b are fixed. And those horns 30
The half dies 2a and 2b having a round split surface are held by the a and 30b so as to face each other with the predetermined clearance C. The center of the split surface is aligned with the wire guide hole. are doing. A slip ring 113 connected to the input lines of the vibration generating means 3a and 3b is mounted on the other surface of the die mounting body 10, and a power supply brush 310 from the ultrasonic oscillator 31 is in contact with the slip ring 113.

In this embodiment, when drawing,
By operating both or one of the vibration generating means 3a and 3b, the half dies 2a and 2b are ultrasonically vibrated toward the center axis of the dies, and at the same time, the rotation driving means 9 is operated to rotate the die mounting body 10. It is pulled out while making it. For this reason, as described above, a large amplitude beating process is performed by the half dies 2a and 2b, and
The hitting position by 2b changes sequentially in the circumferential direction of the wire. Therefore, while the wire W receives the effect of reducing the pull-out resistance, and furthermore, the burring position at the divided surface sequentially moves in the circumferential direction, the roundness is improved. In addition, since only one kind of the half dies 2a and 2b is sufficient, the apparatus is also compact. Although an ultrasonic transducer is used as the vibration generating means in the drawing, it goes without saying that a low-frequency vibration generating device such as a piezo element may be used.

FIG. 10 shows a fourth embodiment of the method and apparatus for vibration drawing of a wire according to the present invention. In this embodiment, low-frequency vibration is used as a vibration type. A fixed die holder 6 is mounted in a die mounting body 10 formed of a rectangular frame, and a movable die holder 7 is arranged so as to face the fixed die holder 6. Dice holder 7
A piezo element is interposed and fixed as vibration generating means 3 between the back of the die and the die mounting body 10. The piezo element 3 is connected to an external drive power supply 31 '. A coaxial guide hole is provided between the movable die holder 7 and the fixed die holder 6, and a guide pin 8 is provided in the die hole of the movable die holder 7.
And a return spring 9 is arranged in the guide hole on the fixed die holder 6 side, whereby the movable die holder 7 is constantly biased in the retreating direction. Notches are provided at opposing portions of the movable die holder 7 and the fixed die holder 6, and half dies 2a and 2b are arranged in these notches and fixed with bolts. The half dies 2a and 2b are opposed to each other with the above-mentioned predetermined clearance C due to the retreat of the movable die holder 7 by the return spring 9.

In the case where the drawing cross section is square, the vibration drawing device 1 is optional from one stage to multiple stages in accordance with the section reduction rate. In the case where the drawing cross-sectional shape is circular, FIG.
It is a multi-stage type as shown in FIG. In this case, as shown in the second embodiment, the half dies are of the oval shape 2a, 2b in the first stage, and are of the round shape 2a ', 2b' in the second stage. Are arranged 90 degrees out of phase with the first stage. The third stage has an oval shape, the fourth stage has a round shape, and a plurality of such alternate sets may be used. Die mounting body 1 for each stage
No. 0 is integrally assembled by inserting a stay bolt into the frame and tightening it, and is fixed to a die mounting plate of the drawing device.

In the fourth embodiment, the one-sided vibration is basically used, but the two-sided vibration may be used in some cases. The frequency may be selected from the range of 0.1 to 300 Hz. To increase the magnitude of the amplitude and increase the force, preferably 10 to 300 Hz, more preferably 50 to 300 Hz.
It is. In this embodiment, in the first stage, the half dice 2
The wire W having a circular cross section is violently beaten from the radial direction by drawing while a is vibrated at a low frequency toward the center axis of the die, and is drawn into an oval cross section while receiving the effect of reducing the drawing resistance. The half-die 2a 'having a phase shift of 90 degrees at the step is pulled out while being vibrated at a low frequency toward the center axis of the die, so that the wire W' having an oval cross-sectional shape has a circular cross-sectional shape while receiving the effect of reducing the drawing resistance. Wire is drawn. Then, in the third stage, the oval half-die 2a is drawn again into an oval cross-sectional shape by low frequency vibration toward the center axis of the die, and then in the fourth stage, the round is shifted from the direction shifted by 90 degrees in phase. It is pulled out while receiving low frequency vibration toward the die center axis of the half die 2a 'having the shape, and drawn into a circular cross-sectional shape. The low frequency vibration generating means may be a mechanical element such as a motor crank in addition to a piezo element, a fluid pressure cylinder, or vibration by air.

[0028]

Next, examples of the present invention will be described. Example 1 1) A square wire having a square section of 0.64 mm on a side was drawn from a wire having a diameter of 1 mm. A half die having a height of 32 mm, a width of 14 mm, and a thickness of 16 mm made of a cemented carbide was used. Divided surface shape is half-width, R50μ at deepest part
m, the approach angle was 10 °, and the length of the bearing part was 2 mm. A pair of half dies were fixed to the tip of a vertical ultrasonic vibration horn driven in phase by a bolt Langevin type ultrasonic vibrator with screws, and the pair of half dies were opposed to each other so that the clearance C was 100 μm. Vibration conditions are: die frequency f: 15 kHz,
Amplitude a: 25 μm (no vibration, one side). 2) The following three types of workpieces were used. Copper wire: C1100W-H, diameter 1mm, tensile strength 42
8N / mm ² , elongation 1% titanium wire (no oxide film): TB340, diameter 1mm,
Tensile strength 370 N / mm ² , elongation 25% Tantalum wire (no plating treatment): TaW, diameter 1 mm,
Tensile strength: 290 N / mm ² , elongation: 20% 3) The drawing speed v is 30 mm / s, and the area reduction rate is 3
It was set to 6%. Processing oil has a viscosity of 32 mm ² / s (40
° C) low viscosity mineral oil was used.

4) As a result of drawing under the above conditions,
Since a large amplitude of 25μm was obtained, copper wire, titanium wire and tantalum wire can be pulled out normally, and the welding phenomenon, which is a problem especially in the case of titanium wire and tantalum wire, can be reliably prevented by the hitting effect, breaking Did not occur. On the other hand, when the (die) drawing without vibration was performed using the die, the copper wire, the titanium wire and the tantalum wire were broken immediately after the drawing. 4) FIG. 11 shows the measurement result of the copper wire withdrawal resistance, FIG. 12 shows the measurement result of the titanium wire withdrawal resistance, and FIG. 13 shows the measurement result of the tantalum wire withdrawal resistance. As is clear from FIG. 11, in the case of the copper wire, when both the pair of half dies were vibrated, the pull-out resistance was about 18 N, and in the case of one-sided vibration, it was 25 N, whereas when the vibration was stopped. Exceeded 100N, and the wire was broken. As is clear from FIG. 12, in the case of titanium wire, when both the pair of half dies were vibrated, the pull-out resistance was about 30 N, and in the case of one-sided vibration, it was 50 N, whereas when the vibration was stopped. Exceeded 100N, and the wire was broken. FIG.
As is clear from 3, the case of tantalum wire (both-side vibration)
And so on. Thus, by using a two-piece type vibrating die, it is possible to pull out a titanium wire or a tantalum wire, which is a hardly drawn wire, with a large cross-section reduction rate, and the drawing resistance can be greatly reduced as compared with the case of the conventional drawing. You can see that. In addition, when the maximum area reduction rate was tested, it was confirmed that a result of 36% for the titanium wire and 45% for the tantalum wire was obtained under the above conditions.

5) FIGS. 14 and 15 show the drawn cross-sectional shapes of the drawn wire obtained by oscillating the two-part type vibrating die on both sides. Both the copper wire (FIG. 14) and the titanium wire (FIG. 15) are excellent. It can be seen that a square cross section is obtained. In addition, as a result of actually measuring the cross-sectional reduction rate, it was 33% in the case of a copper wire and 35% in the case of a titanium wire. In both cases, the error was only about 3% from the set value. From this,
It was found that even when the dice were divided into two, the cross-sectional reduction rate was almost as set.

FIGS. 16 (a) and 16 (b) show the results of measuring the longitudinal surface shapes before and after processing of the drawn wire (copper wire), and there are no large steps or undulations caused by vibration.
The surface roughness is about 1.6 μm Ry, which is about 60 μm that of the strand before drawing (2.66 μm Ry).
%. In other words, it can be seen that the application of the radial ultrasonic vibration does not deteriorate the shape accuracy, but rather improves the surface roughness.

Example 2 Assuming a reduction in area of 12%, a copper wire and a titanium wire were subjected to the method of the present invention, a hole die (conventional method) and a radial ultrasonic vibration short ring vibration system (comparative method) to 250 mm. The sheet was pulled out, and the drawing resistance was measured. The comparison method uses a hole die and applies ultrasonic vibration in the radial direction thereto, and the amplitude a is 2 μm. The drawing conditions in the method of the present invention were the same as in Example 1. The results are shown in FIG. 17 (copper wire) and FIG.
FIG. As is clear from FIG. 17, for the copper wire,
The pullout resistance is 1/6 or less of the conventional method and 1/5 or less of the comparative method. Further, in the case of the titanium wire, both the conventional method and the conventional method broke immediately after the start of drawing, but according to the present invention, the entire planned drawing distance can be drawn. From these results, it can be seen that it is effective to apply vibration in the direction of the center axis of the half-die according to the present invention.

Example 3 1) A round wire was drawn according to the present invention. Two-stage drawing was performed using the apparatus shown in FIG. In the pass schedule, the first stage is oval shape extraction (section reduction rate 8
%), And the second stage was drawn in a round shape so as to obtain a final cross-sectional reduction rate of 19%. The first half of the half die has a semi-elliptical split surface shape, an approach angle of 6 °, and an approach length of 1.5 mm. The wire diameter at the exit is 0.9 mm,
A long diameter of 1.0 mm was obtained. The second half of the half die has a semicircular split surface, an approach angle of 6 ° and an approach length of 1.5 mm, and a wire diameter of 0.9 m at the exit.
m was obtained. The first and second half dies both used SKS3 (HRC58).

2) A pair of half dies are fixed to the tip of a longitudinal ultrasonic vibration horn driven in phase by a bolt Langevin type ultrasonic vibrator, and the first half dice has a clearance C of 100 μm. As if they were facing each other. Second
Were set so that the clearance C was 50 μm. The first half die and the second half die are 9
The phase was shifted by 0 degrees. The vibration conditions were as follows: for both the first and second half dies, the frequency f: 15 kHz and the amplitude a: 25
μm (one side at no load). 3) The material to be processed is the same as the copper wire and the titanium wire in Example 1, the drawing speed v is 30 mm / s, and the processing oil is a low-viscosity mineral oil having a viscosity of 32 mm ² / s (40 ° C.). used.

4) As a result of drawing under the above conditions,
Processing of the hard-to-draw wire became possible, and the roundness, which was inferior to that of a normal hole die, was a value of the degree of drawing with a roller die. That is, FIG. 19 shows the results of measuring the pull-out resistance of the first-stage oval shape and the second-stage round shape die in the case of copper wire.
Shown in First, in the case of an oval-shaped die, the pull-out resistance when no vibration is applied is about 192N using a two-piece type die, whereas it is about 30N when the half dies on both sides are vibrated. , About 1/6 of the case without vibration. Next, in the case of the round-shaped die, it was also found that by vibrating the two-sided die in the same manner, the size was reduced to about 1/7 of the case without vibration.

On the other hand, FIG. 20 shows the result of the same measurement performed on a titanium wire. It can be seen that the pullout resistance in the case of the double-sided die vibration was 61N in the case of the oval shape and 43N in the case of the round shape, whereas in the case of no vibration, the breaking resistance exceeded 200N in the case of the oval shape. . From this, it can be seen that the pull-out resistance can be drastically reduced by the two-part ultrasonic vibrating dies. Therefore, even under severe pull-out conditions such as disconnection in the case of no vibration or a conventional round hole die, there is no disconnection. It was clear that the withdrawal was possible.

5) As a result of observing the cross-sectional shape of the drawn wire in each step, the cross-sectional reduction rate was set to 8% for both the copper wire and the titanium wire when the oval shape was drawn in the first step. After the second round drawing of the round shape, the actual cross-sectional reduction rate was 17%, and the actual cross-sectional reduction rate was 17%, which was almost the same as the set value. 6) FIGS. 21 (copper wire) and 22 (titanium wire) show cross-sectional photographs of each line after the second stage (round shape) drawing. The roundness of both the copper wire and the titanium wire is 38 μm, and in the case of drawing by a hole die, the roundness of about 5 μm is obtained by one-step drawing under the condition of a cross-sectional reduction rate of about 19% with respect to the copper wire. Obtained easily. However, in the case of a titanium wire (without an oxide film), it is difficult to pull out due to seizure. On the other hand, in the case of the present invention, although the roundness is slightly worse at 38 μm as described above, it is better than about 50 μm in the case of the roller die, and it can be seen that the limit is broken. On the other hand, in comparison with a roller die, this method can perform a drawing process of a titanium wire (without an oxide film), but according to the present invention, a feature that a drawing resistance can be greatly reduced is obtained. Therefore, according to the present invention, there is obtained an advantage that the difficult-to-draw material can be drawn under the condition of a higher reduction ratio of the cross section.

FIGS. 23 (a) and 23 (b) show the results of measuring the surface shape in the longitudinal direction of the titanium wire, and the surface roughness was about 1.32 μmRy. It was about 62% compared to the previous 2.12 μmRy. That is, it can be seen that the application of the radial ultrasonic vibration does not deteriorate the shape accuracy in the longitudinal direction, and the surface roughness tends to be improved.

[0039]

According to the first aspect of the present invention described above, a dice which is divided into two parts symmetrically with respect to each other is used. The half-die is vibrated in the direction toward the center axis while pulling out the wire, so a large amplitude can be obtained regardless of the wire diameter, which can prevent welding and drastically reduce the pull-out resistance. Can be drawn out without surface treatment such as formation of an oxide film.

According to the third aspect, since the vibration is a low-frequency longitudinal vibration, an excellent effect can be obtained that the cost can be reduced to about the same level as the conventional hole die. According to the fourth aspect, the process of vibrating the half die in the direction toward the central axis while extracting the material is performed a plurality of times by shifting the phases of the adjacent dies in the extraction direction with a phase shift.
An excellent effect is obtained in that a round wire made of a difficult-to-process material can be pulled out with relatively accurate diameter. According to the fifth aspect, a pair of half dies that are bisected in an axially symmetric manner, vibration generating means connected to the rear portion of each of the half dies, and the half dies having a split surface having an amplitude of at least twice the amplitude. Since it has means for holding it facing each other so as to have clearance,
With a relatively simple structure, prevention of welding and drastic reduction of pull-out resistance can be realized, and an excellent effect that a difficult-to-work and small-diameter wire can be pulled out can be obtained.

According to the sixth aspect, since the half dies are arranged in a plurality of stages and shifted in phase, an excellent effect that the influence of the division of the dies can be reduced and the roundness can be improved can be obtained. According to the seventh aspect, since the half die, the vibration generating means and the holding means are provided with means for rotating about the wire, the influence of the divided surface can be equalized, and the roundness is further improved. An excellent effect is obtained.

[Brief description of the drawings]

FIG. 1 is a partially cutaway plan view showing a first embodiment of a method and an apparatus for vibration drawing of a wire according to the present invention.

FIG. 2A is a cross-sectional view taken along the line YY of FIG. 1B, illustrating the principle of drawing with a half die in FIG.
(B) is sectional drawing which follows the XX line | wire of (a).

FIG. 3A is a perspective view of a half die used in the first embodiment, and FIG. 3B is a cross-sectional view illustrating a fitted state.

FIG. 4A is a cross-sectional view showing the principle of the drawing method according to the second embodiment of the present invention, and FIG. 4B is a cross-sectional view taken along the line ZZ in FIG.

FIG. 5 is a partially cutaway perspective view showing a vibration drawing method and apparatus according to a second embodiment of the present invention.

FIG. 6 is a sectional view taken along line LL of FIG. 5;

7A is a cross-sectional view showing a state of being pulled out by a first-stage die of FIG. 5, and FIG. 7B is a cross-sectional view of FIG. 5A along the line ZZ.

8 (a) is a cross-sectional view showing a state of being pulled out by the second-stage die of FIG. 5, and FIG. 8 (b) is a cross-sectional view of FIG. 5 (a) along the line ZZ.

FIG. 9 is a perspective view showing a third embodiment of the present invention.

10A is a partially cutaway front view showing a fourth embodiment of the present invention, and FIG. 10B is a plan view of the same, and FIG. 10C is a perspective view showing the arrangement of half dies to be used.

FIG. 11 is a drawing resistance diagram when a square wire of a copper wire is drawn according to the present invention.

FIG. 12 is a drawing resistance diagram when a square wire of a titanium wire is drawn according to the present invention.

FIG. 13 is a drawing resistance diagram when a tantalum wire is drawn by square wire according to the present invention.

FIG. 14 is an enlarged cross-sectional view of the drawn copper wire.

FIG. 15 is an enlarged sectional view of the drawn titanium wire.

16A is a profile diagram of the axial surface roughness before the copper wire is drawn, and FIG. 16B is a profile diagram of the axial surface roughness after the copper wire is drawn.

FIG. 17 is a drawing resistance diagram when a copper wire is drawn by the present invention, a conventional method, and a comparative method with a constant area reduction rate.

FIG. 18 is a drawing resistance diagram when a titanium wire is drawn by the present invention, a conventional method, and a comparative method with a constant area reduction rate.

FIG. 19 is a drawing resistance diagram when a two-stage round wire is drawn from a copper wire according to the present invention.

FIG. 20 is a drawing resistance diagram when a two-stage round wire is drawn from a titanium wire according to the present invention.

FIG. 21 is an enlarged cross-sectional view of the drawn copper wire.

FIG. 22 is an enlarged sectional view of the drawn titanium wire.

FIG. 23 (a) is a profile diagram of the axial surface roughness before the drawing of the titanium wire, and FIG. 23 (b) is a profile diagram of the axial surface roughness after the drawing of the titanium wire.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vibration dice device 2a, 2b, 2a ', 2b' Half dice 3a, 3b, 3 Vibration generator 30a, 30b Horn

Claims (9)

[Claims] An axially symmetrical dice is used, and the half dies are opposed to each other by providing a clearance of at least twice the amplitude on the divided surface, and the half dies are directed toward the center axis while the wire is being pulled out. A vibration drawing method for wire rods, characterized in that the wire is vibrated. 2. The method according to claim 1, wherein the vibration is ultrasonic longitudinal vibration. 3. The method according to claim 1, wherein the vibration is a low-frequency longitudinal vibration. 4. The step of vibrating the half-die in the direction toward the central axis while pulling out the wire is performed a plurality of times by shifting the phases of the adjacent dies in the pull-out direction from each other.
2. The vibration drawing method for a wire rod according to item 1. 5. A pair of half dies which are bisected in an axially symmetric manner, vibration generating means connected to a rear portion of each of said half dies, and a clearance of at least twice the amplitude of said half dies on a dividing plane. And a means for holding the sheet in a face-to-face manner. 6. The vibration drawing apparatus for a wire rod according to claim 5, including a pair of half dies having a plurality of stages shifted in phase. 7. A pair of half dies which are bisected axially symmetrically, vibration generating means connected to a rear portion of each of said half dies, and a clearance at least twice as large as the amplitude of said half dies at a dividing plane. A vibration drawing apparatus for a wire rod, comprising: means for holding the sheet so as to face each other, and means for rotating the half-die, the vibration generating means, and the holding means about the wire. 8. The apparatus according to claim 5, wherein the vibration generating means is an ultrasonic vibrator. 9. The vibration generating means is a piezo element.
8. The apparatus for vibration drawing of a wire according to any one of claims 7 to 7.