JPH05185174A - Method for cutting fine wire - Google Patents

Abstract

PURPOSE:To efficiently and stably obtain a cut end part being suitable to precise fitting having no burr, deformation, etc., without needing the following process of correction after cutting. CONSTITUTION:At the upper end of a projecting part in one side of a jig body 1, a fixed side chuck 3 for fixing a wire rope 2 is arranged, and at the intermediate part on the projecting part in the other one side, a movable side chuck 4 is hinged. A weight 5 for loading and a screw 6 for setting escaping distance are arranged in the movable side chuck 4 and a heat insulating material 8 is arranged in the inside of both projecting parts of the jig body 1 and a laser head 7 is arranged in the upper part of the jig body 1.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to various cutting methods.

[0002]

2. Description of the Related Art Conventionally, when thin wires such as wires, piano wires, and glass fibers have been used as constituent parts of various machines and devices, the thin wires are cut into a predetermined length and the tip portions thereof are inserted into other parts. Alternatively, they are often fitted, fixed and fastened. Recently, in order to respond to downsizing and precision of the device, the assembling tolerance between the thin wire and other parts is becoming tighter, and in this case, the tip shape of the thin wire is a shape that does not hinder insertion and fitting. At the same time, it is necessary to control the outer diameter of the cut end. Therefore, in addition to various conventional cutting methods, various tip treatment methods have been proposed.

In the mechanical cutting used in the past,
There is cutting with a cutter, nippers, etc., and it is widely used as a relatively simple cutting method including automated devices. Further, as another cutting method, there is a fusing method in which an electric arc, a plasma jet, a laser, or the like is used as a heat source, and a material to be cut is heated and melted to be cut. On the other hand, as a method of treating the end of the cut portion, for example, Japanese Patent Laid-Open No. 61-747.
In the invention described in Japanese Patent Publication No. 74, a reworking method of melting and chamfering a cut end portion after mechanical cutting is proposed.

[0004]

However, each of the above cutting methods has the following drawbacks. That is, in mechanical cutting, burrs, burrs, and the like are likely to occur at the cut ends, and in the cutting of a wire formed by twisting a large number of strands, unraveling of the wires at the cut ends occurs. In this case, in combination with other parts, rework such as polishing and shaping of the cut end is required to enable particularly precise fitting, which is inefficient. The invention described in the above-mentioned JP-A-61-74774 was proposed for the purpose of improving the efficiency of such reworking work. However, in the point that a step for end treatment is required in addition to the cutting step, the production is performed. It is not possible to expect a significant improvement in efficiency, and there is also a problem in terms of equipment costs, such as the need for a separate heating device for end treatment in addition to the cutting equipment.

Further, in the fusing method, the end of the cut portion is spheroidized due to the surface tension at the time of melting in the course of solidification, and burrs and breakage of the tip do not occur, but the size and shape of the spherical portion at the end are not constant. In most cases, the diameter is larger than the outer diameter of the thin wire. Generally, the shape of the cutting edge is optimized by adjusting the energy amount of the heat source (current, beam intensity, heating gas amount, etc.) and heating time (cutting speed, irradiation time, etc.). The amount of heat applied to the cutting material is large, and the above-described method is not sufficient to prevent uneven spheroidization of the cutting end portion that receives this heat input.
When the outer diameter of the end portion is excessively large as described above, it is difficult to insert and fit into other parts with high accuracy, and there is a problem similar to the mechanical cutting described above that a reworking step is required. ..

Therefore, the present invention was developed in view of the above-mentioned drawbacks of the prior art, and in cutting various fine wires, fine wire cutting that enables precise fitting without requiring a reworking step after cutting. It is intended to provide a method.

[0007]

According to the present invention, when a thin wire is cut by using a heat source such as a plasma arc, a laser or a gas flame, the thin wire is cut while applying a predetermined tension, and immediately after the cutting is finished. This is a method of retracting the cut end from the heat source. Further, when cutting a thin wire using a heat source such as a plasma arc, a laser or a gas flame, while cutting while applying a predetermined tension to the thin wire, the end of cutting is detected by the change in tension during cutting, It is a method of stopping or reducing heating from the heat source immediately after the end.

[0008]

According to the present invention, the fine wire is held and positioned while applying a load in the axial direction according to the diameter of the wire and the energy density of the heat source for cutting, that is, tension, and by a heat source such as an electric arc, plasma or laser. Heat the part to be cut. The thin wire is melted and softened by heating, and a physical cutting action by a given load is added,
Cutting is completed in a shorter time, that is, with a smaller heat input, as compared with cutting by only heating. Further, by displacing the distance corresponding to the heat capacity of the thin wire and the energy density of the cutting heat source in the direction of retracting the cutting end from the heat source upon completion of cutting, radiant heat in the vicinity of the heat source, from the high temperature atmosphere to the cutting end. Adjust the heat input.

Alternatively, in the same manner as described above, the end of the cutting is detected by the change of the tension which starts to decrease at the same time as the start of the cutting, and the heating energy from the heat source is reduced immediately after the end of the cutting. Adjust the heat input to the cut end by stopping.

Due to these actions, various fine wires can be cut (fused) while preventing excessive heat input to the cut end portion at the time of cutting and immediately after cutting.

[0011]

Embodiment 1 FIGS. 1 to 4 show an apparatus and a graph used in this embodiment, FIG. 1 is a front view, FIG. 2 is a graph, FIG. 3 is a front view showing a modified example, and FIG. 4 is a modified example. It is a schematic diagram.

Reference numeral 1 denotes a jig body having a substantially concave shape, and a fixed side chuck 3 for fixing the wire rope 2 is provided on an upper end of one convex portion of the jig body 1. A substantially L-shaped movable chuck 4 is rotatably supported in the middle of the other convex portion, and both chucks 3, 4 are attached to the movable chuck 4.
A weight 5 for applying a tension to the wire rope 2 in between is provided. Further, a retreat distance setting screw 6 for setting a retreat distance of the cut end of the wire rope 2 is screwed into the movable chuck 4.

A laser head 7 for irradiating and cutting a wire beam 2 between the chucks 3 and 4 with a laser beam is installed above the jig body 1. A heat insulating material 8 that protects the jig body 1 from the heat of the laser beam emitted from the laser head 7 is provided inside both convex portions of the jig body 1.

In the present embodiment, the SUS composed of 49 strands (diameter 0.06 mm) is used by using the apparatus having the above-mentioned structure.
The wire rope (outer diameter 0.55 mm) made was cut using a Nd.YAG laser (beam output 3 J, pulse width 3 ms, frequency 10 HZ) as a cutting heat source. Figure 2
As shown in, the tension applied during cutting is 1.2 kgf / c.
Within the range of m ^{2 to} 2.5 kgf / cm ² , there was no burr and unraveling, and it was possible to obtain a good cut end having the same outer diameter as the wire rope outer diameter. In cases other than the above load range,
At 1.2 kgf / cm ² or less, the outer diameter of the cut end becomes larger than that of the wire rope, and when the tension is almost 0, the spherical portion at the tip is often re-fused by the next laser pulse. At 2.5 kgf / cm ² or more, the spheroidization of the cut end was not sufficient, and the strand was broken. In addition,
In this example, the above results were stably obtained when the retracted distance after cutting was 2 mm or more.

According to this embodiment, by optimizing the heat input to the cutting end at the time of cutting, excessive spheroidizing or loosening of the cutting end can be prevented, and cutting suitable for precise fitting can be performed. It becomes stable and easy.

3 and 4 show a modification of this embodiment. In the modified example shown in FIG. 3, the fixed chuck 3 in the present embodiment is eliminated and a movable chuck 4a is used instead, and both chucks 4a for chucking the wire rope 2 are provided.
4b is configured to be movable. In this application example, since both ends of the cut end are retracted, in addition to the effect of the first embodiment, there is also an effect that a good shape can be obtained at both ends.

FIG. 4 shows an outline of an example of application of the present invention to an automatic cutting device. 11 is a long steel wire wound on a reel,
Reference numeral 12 is a drive roller connected to a drive motor and a counter (not shown) such as a pulse generator and also serving as a length measurement, 13a and 13b are guides, 14 is a second drive roller, 15 is a plasma torch, and 16 is a slag receiver. , 17
Is a guide for discharging a steel wire.

In this application example, after the steel wire having a predetermined length is sent out, the driving rollers 12 and 14 are reversed to apply tension to the cut portion of the steel wire 11. Although it is possible to use a separate detection device to detect the tension, in this application example, the tension is managed by controlling the rotational torque of the drive rollers 12 and 14. Further, the withdrawal after cutting is also performed by the rotation of the drive rollers 12 and 14.

When the long steel wire 11 is repeatedly cut, the cut long steel wire 11 is discharged by the drive roller 14 and a new long steel wire 11 is driven by the drive roller 12 which also serves as the length measurement. The guides 13a and 13b are used as guides to send out to the second drive roller 14. At this time, the guide 13a,
The distance between 13b should be 30mm or less, and guide 1
By expanding the entrances of 3a and 13b, it is possible to perform accurate guidance and positioning during cutting. This application example is very easy to apply to automation.

The present invention can be applied to the cutting of a wide range of materials such as metal, resin and glass by various heat sources such as plasma and arc heat, and is not limited to the heat sources and materials of this embodiment.

Further, the feature of the present invention is to apply tension to the material to be cut at the time of cutting and to retract the cutting end from the heat source immediately after the cutting as described above. The driving means is not limited to the means described in this embodiment.

[0022]

[Embodiment 2] FIGS. 5 to 7 show an apparatus and a graph used in this embodiment, FIG. 5 is a front view of a main portion, FIG. 6 is a schematic configuration diagram, and FIG.
Is a graph. In this embodiment, the movable chuck 4 of the first embodiment is eliminated, a movable tension detecting chuck 21 is provided, and a tension detecting load cell 22 is provided between the tension detecting chuck 21 and the jig body 1. It is different in that it is configured by being interposed, and the same numbers are given to other same components and the description thereof is omitted.

In this embodiment, a movable tension detecting chuck 21 is provided on the jig body 1 via a tension detecting load cell 22. A load cell amplifier 23 is connected to the tension detection load cell 22, and the load cell amplifier 23
A controller 24 is connected to the. A laser power supply 25 is connected to the controller 24, and a laser oscillator 26 is connected to the laser power supply 25.

The cutting using the apparatus having the above-mentioned structure is carried out by applying a tension of 1.5 kgf / mm ² to the SU.
S wire rope 2 (three strands with a wire diameter of 0.26)
Is fixed between the fixed side chuck 3 and the tension detection side chuck 21, and the beam 27 (continuous output 3J) oscillated from the laser oscillator 26 is 1.
The wire rope 2 is irradiated with light having a diameter of about 5 to 2 times.

FIG. 7 shows a change in tension during cutting and control of laser output. In the above process, the tension that starts to decrease at the same time as the start of cutting is detected by the load cell 22 connected to the tension detection side chuck 21, and the output of the laser 27 is reduced to about 50% at the end of cutting by the program preset in the controller 24. By controlling so as to stop the oscillation, the cut end having a suitable shape having the same size as the diameter before cutting was stably obtained.

According to the present embodiment, the amount of heat input to the cut end can be optimally controlled, so that the size and shape of the cut end suitable for precise fitting can be stably obtained.

The feature of the present invention is to apply tension to the material to be cut at the time of cutting and control the heating from the heat source by detecting the end of cutting as described above. The detection and control means are not limited to the means described in this embodiment. Further, in the present invention, a wide variety of heat sources and types and sizes of the material to be cut can be dealt with by appropriately selecting the tension applied to the material to be cut and the energy amount of the heat source at the end of cutting.

[0028]

As described above, according to the thin wire cutting method of the present invention, when cutting various thin wires such as wires, piano wires or glass fibers, there is no burr, burrs and deformation and precise fitting. The cutting end portion applicable to the above can be obtained efficiently and stably without the need for post-processing such as reworking after cutting, and has a remarkable industrial effect.

[Brief description of drawings]

FIG. 1 is a front view showing a first embodiment.

2 is a graph showing Example 1. FIG.

FIG. 3 is a front view showing a modified example of the first embodiment.

FIG. 4 is a schematic diagram showing a modified example of the first embodiment.

FIG. 5 is a front view of a main portion showing a second embodiment.

FIG. 6 is a schematic configuration diagram showing a second embodiment.

FIG. 7 is a graph showing Example 2.

[Explanation of symbols]

 1 jig body 2 wire rope 3 fixed side chuck 4 movable side chuck 5 load weight 6 retract distance setting screw 7 laser head 8 heat insulating material

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display location B26F 3/02 7411-3C 3/06 7411-3C // B23K 101: 32

Claims (2)

[Claims] 1. When cutting a thin wire by using a heat source such as a plasma arc, a laser or a gas flame, the thin wire is cut while applying a predetermined tension, and the cut end is retracted from the heat source immediately after the cutting. A thin wire cutting method characterized by: 2. When cutting a thin wire using a heat source such as a plasma arc, a laser or a gas flame, the thin wire is cut while applying a predetermined tension, and the end of the cutting is detected by a change in tension during cutting. Then, immediately after the end, the heating from the heat source is stopped or reduced, and the thin wire cutting method.