JPS62181833A - Wire feed device in wire electric discharge machining device - Google Patents

Abstract

PURPOSE:To make it possible to sustain the machining speed and the machining accuracy, by providing a wire guide having a V-shape groove, and a nozzle which is movably supported to the guide so that the rigidity and straightness of a pipe in a wire feed device are ensured. CONSTITUTION:When a wire 2 is stretched so that it makes into contact with an idle roller 20 and feed-out positions 21, 22 on a drive device 9, the centers of the wire 2, a nozzle 36, a pipe 18, a hole 19 and the like coincide substantially with each other, and are aligned with each other in a position where the position of the groove section guide of a V-shape guide 5 makes into contact with the wire 2. The outer diameter of the pip 18 is only 4-5.5mm, and therefore, the guide 37 would interfere with the V guide 5 if a guide 37 is pulled back leftward by means of a cylinder 28, Accordingly, a casing 34 is moved in the direction X by a distance (a) to remove the V guide 5 from the guide position, and a flat guide 37 is pulled back leftward by means of the cylinder 28. Further, when the nozzle 35 is pulled back leftward by the distance (a) by means of a cylinder 35, the centers of the nozzle 36 and the pipe 18 again substantially coincide with each other. Thus, the pipe diameter is made to be large to ensure the rigidity thereof even if the hole diameter 23 is not changed, thereby it is possible to ensure also the straightness.

Description

[Detailed description of the invention] [Field of application of the invention] The present invention relates to a wire feeding device for a wire electrical discharge machine.

[Background of the invention]

3 to 5 schematically show the wire electrical discharge machine.

The wire 2 wound in a coil on the reel 1 has a weight 3
A v-guide 5.6 and a flat guide 7.8 are placed above and below the workpiece 4 and pass through a predetermined path.
is guided by the drive device 9, and is discharged into a packet 10.

When machining, a voltage is applied to the wire 2 by the current-carrying tip 11, 12 to cause an electric discharge between the wire 2 and the workpiece 4, and to move the workpiece 4 and the above-mentioned wire feeding system relative to each other.

13 is a reverse running prevention device consisting of a pair of eccentric rollers, 14 is a wire feeding device consisting of a pair of drive rollers, 15 is a detector for detecting the presence or absence of tension in the wire 2, and 16.17 is a processing part number. A nozzle 18 for supplying machining fluid is a pipe for inserting the wire 2 into the machining start hole 19 of the workpiece 4 .

In the wire electric discharge machine, the feed-out position 21 of the idle roller 2 ( ) and the feed-out position 1122 of the drive device 9 are arranged so as to be substantially vertical. In addition, the position 21 and the position [22
When the wire 2 is stretched so that the wire 2 is in contact with the wire 2, the center of the wire 2, the center of the lower nozzle 17, and the center of the pipe 18 are approximately aligned, and the guide position of the guide 6 is in circumscribed contact with the wire 2. It is located in

FIG. 4 is a sectional view taken along the line ■-■ in FIG.
As shown in the figure, the center of the wire 2 placed at the guide position of the V guide 5 and the center of the hole 23 of the nozzle 16 are arranged so as to substantially coincide with each other.

Note that the holes 23 are formed to have a diameter of approximately 6jIII in order to effectively discharge sludge generated during electrical discharge machining and improve machining speed and machining accuracy.

The case 24 includes the above-mentioned current-carrying chip 11, the V guide 5,
An upper guide section composed of a flat guide 7, a nozzle 16, etc. is arranged and placed on the slide mechanism 25.

The slide mechanism 25 is a device for moving the upper guide part relative to the base 26 in the left-right direction in FIG. The repeatability during movement is within 2 μm due to the use of surgical water.

When there are multiple machining points in the same workpiece 4, for example, in the case of progressive die machining for press working, etc.
When the wire 2 is inserted into the new machining start hole 19 after machining of one location is completed and the next location is to be machined, the wire 2 is first cut by the cutter 27, and the wire 2 remaining in the workpiece 4 is cut into packets. 10, and position the wire feeding system in the new machining start hole 19 of the workpiece 4. That is, when the wire 2 is stretched so as to be in contact with the positions [21 and 22], the centers of the wire 2, the nozzle 16, the nozzle 17, the pipe 18, and the hole 19 are approximately aligned, and the V guide 5,
(2) Align each part so that the groove guide position of the guide 6 contacts the wire 2.

Since the outer diameter of the wire 2 is 0.2 to Q4 my, and the outer diameter of the pipe 18 is 2 to 2.5 mw, the flat guide 7 on which the current-carrying tip 11 is mounted is changed from the state shown in FIG. If the pipe 18 is simply pulled back to the left by the cylinder 28, the pipe 18 will interfere with the V guide 5 and cannot be passed through.

Therefore, by moving the case 24 in the X direction, the V guide 5 is removed from the guide position, and the flat guide 7 is pulled back to the left by the cylinder 28, creating a gap sufficient for the pipe 18 to pass through. Also, when the flat guide 8 and the v-guide 6 guide the wire 2, the gap between the wire 2 and the wire 2 is 1 μm.
Therefore, the flat guide 8 on which the current-carrying tip 12 is mounted is also pulled back to the left by the cylinder 29 so that the tip of the wire 2 can smoothly pass through the guide portion. In addition, the inner diameter of the hole 19 is about 3 mm when the plate thickness is 50 mm or less. Subsequently, the wire supply device [14 is operated in the direction of the arrow to clamp the wire 2, and the wire 2 is fed out using a vertical movement mechanism (not shown) until the tip 30 of the pipe 18 comes into contact with the upper end surface 31 of the V guide 6. further lowered by wire 2
is sent to the drive device 9, and the wire 2 is inserted into the machining start hole 19.
insert it into the Thereafter, the pipe 18 is pulled up, the wire supply device 14 is opened, the case 24 is returned to the processing position, the V guide 5 is returned to the guide position, and the flat guide 7.8 is set.

In addition, if the wire 2 breaks at the discharge point with the workpiece 4 due to inappropriate machining conditions or rust on the surface of the workpiece 4, the wire 2 should be fixed until the breakage point exits the workpiece 4 or at a predetermined position. After rewinding until it returns and positioning the wire feed system described above in the machining start hole 19 of the workpiece 4, the wire 2 is inserted into the workpiece 4 in the same manner as in the case of the progressive type machining described above.

Note that 32 is a cylinder for releasing the detector 15;
33 is an idle roller.

FIG. 5 shows ■-■ in FIG. 3 when the pipe 18 is descending in order to insert the wire 2 into the processing start hole 19.
FIG.

The V guide 5 is moved rightward by the slide mechanism 25 in order to allow the pipe 18 to pass, and since the outer diameter of the pipe 18 is 2 to 2.5 mm as described above, the pipe 18 is moved between the V guide 5 and the hole 23. The tip 30 can pass through the gap formed between the upper end surface 3 and the vertical moving mechanism.
It can move until it touches 1.

Furthermore, if, for example, there is a hole left in the machining start hole 19 from the time of drilling, the side surface of the pipe 18 or the tip 3
When the pipe 18 comes into contact with the pipe 18, bending force or compressive force is applied to the pipe 18, deforming the pipe 18. Therefore, when a certain force is applied to the pipe 18, the operation of the vertical movement mechanism of the pipe 18 is stopped. A device (not shown) is provided.

However, for example, when processing a workpiece with a thickness of 200 mm, the length of the pipe 18 must be 150 oa longer than in the case of a plate thickness of 501 mm, and the deformation under the same force will be smaller. . For this reason, if the sensitivity of the safety device is increased, it will operate even with the slightest force, which will not only reduce the operating efficiency of the wire electrical discharge machine, but also cause the pipe 18, which has excellent straightness, to operate. The problem was that it was difficult to manufacture.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the drawbacks of the prior art described above and to provide a wire feeding device that can use a thick pipe.

[Summary of the invention]

If the thickness of the workpiece exceeds 5Qmz, it will be difficult to drill a small diameter hole straight, so we focused on making the hole diameter about 6mm. The above objective was achieved without changing the inner diameter of the nozzle by moving the nozzle so that the centers of the holes of the nozzle substantially coincided with each other.

[Embodiments of the invention]

An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows one embodiment of the present invention, and in this figure, the same parts as in FIGS. 3 to 5 are denoted by the same reference numerals.

The case 34 houses the v-guide 5, a flat guide 37 on which the current-carrying tip 11 is mounted, and a nozzle 36 that is slidably driven by the cylinders 28 and 35, and is placed on the slide mechanism 25.

When inserting the wire 2 into the machining start hole 19, when the wire 2 is stretched so as to be in contact with the position W121 and the position 22, the centers of the wire 2, nozzle 36, nozzle 17, pipe 18 and hole 19 are approximately aligned. , V guide 5, and (2) align each part so that the groove guide position of the guide 6 contacts the wire 2.

Since the outer diameter of the wire 2 is 0.2 to 9.4 mm and the outer diameter of the pipe 18 is 4 to 5.5 mx, simply pulling the flat guide 37 back to the left by the cylinder 28 will cause the pipe 18 to It interferes with the V guide 5 and cannot pass through.

Therefore, the case 34 is moved by a distance in the X direction.

The V guide 5 is removed from the guide position, and the flat guide 37 is pulled back to the left by the cylinder 28.

The center of the hole 23 of the nozzle 36 is separated by a from the center of the pipe 18 as the case 34 moves, so if the nozzle 36 is pulled back to the left by the amount a by the cylinder 35, the center of the nozzle 36 and the pipe 18 are separated by a. The centers of are approximately coincident again.

Since the inner diameter of the hole 23 and the inner diameter of the machining start hole 19 are approximately 6 mm, even if the outer diameter of the pipe 18 is 4 to 5.5 mm, which is about 2% or more of the conventional diameter, the via 18 is the same as the hole 23. 1
9 can be passed.

In other words, without changing the inner diameter of the hole 23, which affects machining speed and machining accuracy, the outer diameter of the pipe 18 can be reduced to approximately 2 times the conventional diameter.
Since it can be more than doubled, rigidity can be ensured, and straightness can also be easily ensured.

FIG. 2 shows another embodiment.

Is the flat guide 38 at the bottom? J39, and engages with a protrusion 41 provided at the top of the nozzle 40.

The nozzle 40, which is slidable in the left and right directions, is biased in the X direction by a spring 42, and the end face 43 is pressed against the case 44 during processing.
The center of the nozzle 40 substantially coincides with the center of the pipe 18 . Further, during processing, the distances between the rear end 46 of the flat guide 38 and the rear end 47 of the nozzle 40 and the inner end surface 45 are respectively a, and @39 and the convex portion 41 are engaged with each other with a gap Z. It matches. Here, the gap Z is formed to be equal to the difference between the distance and the distance a.

With the above configuration, when the pipe 18 is passed through the guide section and the hole 23, the case 44 is moved in the X direction by a distance a, and then pulled back by the cylinder 28 until the rear end 46 comes into contact with the end surface 45. , the nozzle 40 also moves accordingly, and at the same time the rear end 47 comes into contact with the end surface 45, the center of the hole 23 substantially coincides with the center of the pipe 18,
The same effects as in the previous embodiment can be obtained.

Note that although this embodiment shows the case where the current-carrying chip 11.12 is placed on the flat guide 8, 37, 38, the current-carrying chip 11.12 may be fixed to the V-guide 5.6 side. Of course.

In addition, if you do not perform taper processing, flat guide 8.37.3
It goes without saying that 8 is not necessary.

[Brief explanation of drawings]

1 and 2 are front sectional views of a wire feeding device according to the present invention, FIG. 3 is a schematic diagram of a wire electrical discharge machine, and FIGS. 4 and 5 are sectional views taken along the line ■-■ in FIG. 3. be. 2...Wire 5...V guide 18...Pipe 19...Machining start hole 36...Nozzle 40...Nozzle.

Claims (1)

[Claims] In a wire feeding device of a wire electrical discharge machine, which inserts a wire fed through a pipe into a machining start hole of a workpiece together with the pipe, then pulls back only the pipe and supplies the wire to the machining start hole of the workpiece to perform machining. A wire consisting of a guide having a V-shaped groove and a nozzle slidably supported on the guide having a V-shaped groove, and characterized in that the center of the pipe and the center of the nozzle are approximately aligned when the pipe is inserted. Wire feeding device for electric discharge machine.