JPS60104619A - Method of automatically connecting wire electrode in wire cut electrospark machining apparatus - Google Patents

Abstract

PURPOSE:To enable a wire electrode to be automatically connected securely and easily by inserting the wire electrode into an elastically expansible opening in a wire guide jig inserted in a working start hole in a workpiece, transferring the jig to make the wire electrode extend through the start hole and then removing the jig. CONSTITUTION:A wire guide jig 9 is provided with an opening 9' consisting of opening pieces 9', 9''... slitted like a cross longitudinally of a pipe from one end and flared. The jig 9 is previously disposed movably in a working start hole 3 in a workpiece 1 which is displaced to align the center of said hole 3 with the electrode insertion position Xa in which a chuck 14 is installed. The jig 9 is held by the chuck 14, while delivery rollers 10 and the upper guide 11 are moved to the position Xa. And an electrode wire 4 is sent out to be securely introduced into the opening 9' even if the end of the wire is somewhat bent, and the chuck 14 is moved in the delivery direction so that the electrode 4 is taken up by a take-up roller.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for automatically connecting a wire electrode in a wire-cut electric discharge machining device, and in particular a method for inserting a wire electrode into a machining start hole formed in a workpiece, and starting electric discharge machining from the machining start hole. In the wire-cut electric discharge machining apparatus configured to start the machining process, a wire guide jig is used, which has a movable metal inside the machining start hole and an opening into which the wire electrode is inserted and which is elastically expandable and contractable. The present invention relates to an automatic wire connection method for a wire electrode, which allows the wire electrode to easily penetrate into the processing start hole.

Generally, machining is performed using a wire-cut electric discharge machining device that applies voltage between a linear electrode such as a wire (called a wire electrode) and the workpiece, and processes the workpiece into an arbitrary shape by electric discharge. In this case, a machining start hole is previously formed in the workpiece to allow the wire electrode to pass through, and machining is started through the machining start hole.

By the way, in recent years, as shown in FIG. 1, a feed roller 6 that raises the wire electrode 4 by sandwiching it therein and rotating it, and a wire guide nozzle 5 that raises the wire electrode 4 while fully restraining it. Many wire-cut electric discharge machining apparatuses are used in which the tip of the wire electrode 4 is automatically inserted into the machining start hole 3 formed in the workpiece 1. However, as shown in FIG. 1(4), when the workpiece 1 has a relief part 2, the distance from the wire guide nozzle 5 to the machining start hole 3 becomes long. There is a problem that the tip of the wire terminal 4 may not be inserted into the processing start hole 3 (note that the reference numeral 7 in FIG. 2 represents a guide roller). Therefore, as shown in Figure 1 (J3), Figure 1 (4)
In the illustrated example, the inner diameter of the machining start hole 3 is increased and a cylindrical bush 8 made of a conductive material is driven into the bush 8.
A method of using the inner hole as the machining start hole is being considered. That is, in this method, by making the bushing 8 an appropriate length, the tip of the bushing 8 is brought close to the wire guide nozzle 5, so that the wire electrode 4 can be reliably inserted into the inner hole of the bushing 8. This is what I did. Certainly, this method has the advantage of being able to reliably insert the wire electrode into the machining start hole on the one hand, but on the other hand it has the following drawbacks.

That is.

(+) By making the bush 8 longer, the amount of processing increases accordingly, and the processing time becomes longer.

(11) Since the diameter of the prepared hole (corresponding to the machining start hole 3 shown in FIG. 1) to be drilled in the workpiece 1 in order to drive the bush 8 becomes larger, 1, for example, a die having a bearing hole with a narrow groove width is used. In the case of machining, it is not possible to make the groove width narrower than the outer diameter of the bushing 8.

(il) The bushing 8 is disposable after each processing, which is uneconomical.

The present invention aims to solve the above-mentioned drawbacks, and therefore provides a method for automatically connecting wire electrodes in a wire-cut electrical discharge machining apparatus.

In a wire-cut electric discharge machining device configured to insert a wire electrode into a machining start hole formed in a workpiece and start electric discharge machining from the machining start hole, the wire electrode is movable within the machining start hole. and a wire guide jig having an opening into which the wire electrode is inserted and which is elastically expandable and contractable.

By inserting the wire guide jig into the processing start hole and inserting the wire electrode into the opening, the wire guide jig moves in response to feeding of the wire electrode. The present invention is characterized in that the wire electrode is connected after the wire guide jig is removed after the wire guide jig is inserted through the machining start hole.

This will be explained below with reference to the drawings.

Figure 2 shows the wire kite jig used in the present invention, Figure 2 (4) is a plan view, and Figure 2 (B) is a wire kite jig used in the present invention. ) is shown. Further, FIG. 3 shows an explanatory diagram for explaining the present invention in detail. Reference numerals 1, 3 and 4 in the figure correspond to those in FIG. 1, 9 is a wire guide jig, 9' is an opening, 9' is an opening piece, 10 is a delivery roller, 11 is a corner guide, 12 is a lower guide, 13 is a tension roller,
14 represents a chuck.

The wire guide jig 9 used in the present invention is made of an ultra-thin walled pipe, such as an elastic stainless steel pipe. As shown in FIG. 2, an opening 9' consisting of opening pieces 9', 9', . It's profitable. The wire guide jig 9 is a jig for inserting the wire electrode 4 into the processing start hole 3, as will be described later.

The wire electrode 4 inserted into the opening 9' is introduced into the processing start hole 3. Further, the wire guide jig 9 used in the present invention has a wire electrode 4 as shown in FIG.
opening piece 9 that can be elastically expanded and contracted to facilitate insertion of the
Since the wire guide jig 9 is provided with openings 9' consisting of ", 9", . . . , the diameter φ of the straight tube' portion of the wire guide jig 9 may be small. The automatic wire electrode connection method of the present invention using the wire guide jig 9 will be described below with reference to FIG.

In FIG. 3, the workpiece 1 and the delivery roller
9. The upper guide 11 is placed on or supported by an XY axis table and a UV moving axis table (not shown), both of which are configured to be freely movable under control.

The 9th position XO indicates the machining start position, and the drive device 1' (not shown) is located at a distance α from the machining start position Xo (hereinafter referred to as the electrode insertion position). Note that a wire guide jig 9 is movably disposed in advance in the machining start hole 3 formed in the workpiece l, for example, via grease.

First, the upper body l of the wave force U is moved so that the center of the machining start hole 3 coincides with the electrode insertion position txα where the chuck 14 described above is installed. Next.

The wire guide jig 9 is held by the chuck 14, and the delivery row "10" and the upper guide 11 are moved to the electrode insertion position X8.

Then, the wire electrode 4 is sent out while being guided by the upper guide 11 by a delivery roller 1O that rotates while holding the wire electrode 4 therebetween. As a result, since the opening 9' is provided in the wire guide jig 9, even if the tip of the wire electrode 4 is slightly curved, the tip of the wire electrode 4 can be securely inserted into the opening 9'. can be introduced. Then, the tip of the wire electrode 4 has an opening 9
' After the wire electrode 4 is introduced into the chuck 1, the chuck 1 is
4 in the electrode sending direction. Note that since the opening piece 9' constituting the opening 9' of the wire guide jig 9 is elastically expandable and contractible, the opening 9' can be processed while guiding the tip of the wire electrode 4. It moves inside the starting hole 3. In this way.

The wire electrode 4 is inserted into the processing start hole 3 reliably and easily, and when the tip of the wire electrode 4 passes through the processing start hole 3 and reaches a predetermined position, the feed roller 10
The feeding of the wire electrode 4 is stopped. In this state, the chuck 14 is lowered until the tip of the wire electrode 4 comes out of the opening 9'.

Then, while the wire electrode 4 is inserted into the machining start hole 3, the workpiece 1 is
．． The feed roller 10 and the upper guide 11 are indicated by the arrow
After moving the wire electrode 4 by a distance α in the direction, the wire electrode 4 is sent out again. In this way, the tip of the wire electrode 4 sent out is connected to the lower guide 12. Automatic connection of the wire electrode 4 is completed by being wound up by a winding roller (not shown) via the tension roller 13.

As described above, in the wire electrode automatic connection method of the present invention described with reference to FIG. However, in the present invention, the wire guide jig 9 may be moved by the feeding force of the wire electrode 4 without using the chuck 14.

As explained above, according to the present invention, not only can wire electrodes be automatically connected reliably and easily, but also the diameter of the wire guide jig can be made small, so the inner diameter of the machining start hole can be made small. It is not a stupid Q, and has excellent effects such as being economical as the wire guide jig can be used repeatedly.

[Brief explanation of the drawing]

Figure 1 ■ and (2) are explanatory diagrams of the conventional example, Figure 2 (4)
and ■ are explanatory diagrams of one embodiment of the wire guide jig used in the present invention, and FIG. 3 is an explanatory diagram for explaining the wire electrode automatic connection method of the present invention. In the figure, 1 is a workpiece, 3 is a machining start hole, 4 is a wire electrode, 9 is a wire guide jig, and 9' is an opening. 9" is an opening piece, 10 is a delivery roller, 11 is an upper guide, 12 is a lower guide, 13 is a tag/jon p-ra, 14
represents chuck. Patent Applicant: Discharge Precision Machining Research Institute Co., Ltd. Representative Patent Attorney Mori 1) Hiroshi (3 others) $1 Figures 1, 2 JP-A-Sho ct+-1o46l! J(4) Figure 3

Claims (1)

[Scope of Claims] A wire-cut electric discharge machining device configured to insert a wire electrode into a machining start hole formed in a workpiece and start electric discharge machining from the machining start hole. A wire guide jig is provided which has a movable inner metal and has an opening into which the wire electrode is inserted and which is elastically expandable and contractable. The wire guide jig is inserted into the processing start hole, and the wire electrode is inserted into the opening, and the wire guide jig moves in response to feeding of the wire electrode. A method for automatically connecting a wire electrode in a wire-cut electrical discharge machining apparatus, characterized in that the wire electrode is connected after the wire guide jig is removed after the wire is passed through the machining start hole.