JPH01205938A - Electric discharge drilling device - Google Patents

Abstract

PURPOSE:To control the deflection turn of the top edge part of a thin electrode by installing an electrode holding member for fixing the thin electrode at an arbitrary angle with respect to the axis of revolution onto an electrode chuck. CONSTITUTION:After the basic part of a thin electrode 1 is fitted into an electrode holding hole on an electrode holding member 8, the top edge part is inserted into the guide hole 15 of a guide member 3, and the tightening tool 13 of an electrode chuck 2 is operated, paying attention so that no bending moment is generated on the thin electrode 1 between the guide member 3 and the electrode holding member 8, and the electrode holding member 8 is tightened, and the basic part of the thin electrode 1 is surely held. The thin electrode 1 is revolved by a motor M, and the electric discharge drilling work is carried out, supplying an electric discharge working power source by a sliding contact element 6. With such constitution, the deflection of the top edge part of the thin electrode 1 is prevented at the position of the guide member 3, and the generation of deflection operation of the guide member 3 is prevented, and the straightness in the drilling work for a work 7 is maintained, and correct working is permitted.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to an electrical discharge drilling device that is attached to a wire electrical discharge machining line or the like.

Conventional electrical discharge hole drilling equipment, especially electrical discharge drilling equipment for machining initial holes etc. for wire electrical discharge machining, has a relatively small diameter (usually about D = 1 mm to 3 mm) and a long diameter (usually L = about 3 mm). (approximately 180 mm) using a thin electrode. Also,
In order to uniformly wear out the tip of the fine electrode and perform rational processing,
It is common to perform this while rotating the thin electrode. Therefore, if the fine electrode is warped, the tip of the fine electrode, which is rotated while being gripped by the base, will swing around the axis of rotation of the chuck. The radius of is further increased by the centrifugal force generated by the rotation of the fine electrode. Therefore, a configuration is adopted in which a guide member that rotatably holds the tip of the fine electrode is provided to maintain the position of the tip of the fine electrode on the extension of the rotation axis of the chuck, thereby suppressing whirling.

Figure 4 is a diagram that briefly explains the conventional discharge hole device.
The thin electrode 1 is held at its base by the electrode chuck 2, and
The tip portion is rotatably held by a guide member 3 on an extension of the rotation axis of the electrode chuck 2 . The electrode chuck 2 is a collet chuck that has a sleeve 4 that holds the thin electrode 1 straight.

The electrode chuck 2 is configured to be rotated by a motor M. Further, the guide member 3 is provided via a shaft 5 that is vertically slidable, and the vertical position of the shaft 5 is controlled by an actuator (not shown). Note that the shaft 5 is a thin member because it requires a relatively large stroke. Reference numeral 6 is a sliding contact that supplies electric discharge machining power to the electrode chuck 2. Reference numeral 7 is a workpiece.

In such a configuration, the fine electrode 1 is rotated by the drive of the motor M and electric discharge machining power is supplied by the sliding contact 6.
Electric discharge drilling is performed while driving the entire body up and down using a feeding mechanism (not shown). Because it is a member, there may be a pre-movement in which it swings left and right as the fine electrode 1 rotates.Then, if the hole opened in the workpiece 7 is larger than the diameter of the thin snow Mil, the straight line of the hole will be drawn in Jξ. Processing speed is low due to loss of properties and the area to be processed increases.
There was a problem that ζ.

On the other hand, if the rigidity is improved by increasing the thickness of the shaft 5 on which the guide member 3 is installed, it is possible to prevent the pre-movement of the guide member 3, but the warped narrow electrode 1 and the guide member 3, which would cause a loss of the fine snow V11, it is still difficult to perform appropriate discharge hole numbering.Furthermore, this In this case, rotating the III electrode 1 may cause an overload on the motor M, which may cause problems such as applying IEI ('fA) to various parts.

Problems to be Solved by the Invention It is an object of the present invention to prevent damage to the thin 8-pole or to damage the driving means for rotating the I[l electrode] even if the fine electrode has warpage. The object of the present invention is to provide a device that can hold the tip of the Ill electrode on the rotational axis of the chuck and suppress the rotation of the tip of the fine electrode without causing any adverse effects or twisting.

Means for Solving the Problems It is possible to fix a thin electrode at an arbitrary angle with respect to the rotation axis of a rotating electrode chip.

The electrode gripping member (installed on the working electrode chuck) grips the base of the thin electrode, the tip of which is rotatably held by the guide member, onto the electrode chip at any corner along its warp.

Embodiment As shown in FIG. 1, the discharge hole drilling GJ apparatus has an electrode chuck 2. A guide member 3 is provided.

The electrode chuck 2 has a structure in which the rest is rotationally driven by a motor M, and an electrode gripping member 8 is placed at the tip of the chuck 2 by being sandwiched between it and a seat 14 by a fastener 13, and has a collet-type gripping structure. It becomes.

As shown in FIG. 2, the electrode gripping member 8 is a spherical body made of a good electrical conductor and has an electrode gripping hole 9 penetrating in the diametrical direction. The electrode holding hole 9 can be reduced in diameter by applying force when tightened from the outside by the fastener 13.

The guide member 3 is provided at the lower end of the shifter 5 which can be slid up and down by the actuator A, and has a guide hole 15 having a diameter 7'i,000 larger than the diameter of the electrode 1. The holes 11 to 15 are arranged at positions where the axis of rotation of the electrode chuck 2 passes through ri.

A discharge 7JII power is supplied between the electrode chuck 2 and the workpiece 7. Symbol 6 is the rotation Jruichi city pole f-1/tsuk2
It is a sliding contact for.

In the above configuration, when machining the discharge hole, first the base of the fine electrode 1 is fitted into the electrode gripping hole 9 of the electrode gripping member 8 as shown in FIG. through the guide hole 15 of the guide member 3, and the distal end thereof is made to protrude from the guide member 3 by the necessary amount.

Next, between the guide member 3 and the electrode gripping member 8, the light snow Ml
1, while being careful not to cause any bending moment], that is, to keep the warpage that has occurred in the fine electrode 1 in its natural state, operate the fastener 13 of the electrode tip 2 to remove the electrode grip part 448. Tighten to securely grip the base of the thin electrode 1.

In this case, since the electrode gripping member 8 installed on the electrode chuck 2 is spherical, it can be freely rotated between the fastener 13 and the seat 14 before being fixed by the fastener 13, and the guide member 8 1I with its tip rotatably held by
The base of the ll electrode 1 can be gripped by the electrode chuck 2 at any angle along its warp.

Therefore, in a natural state, no bending moment is generated in the fine electrode 1 held by the electrode chuck 2, and the center of its tip coincides with the center of the guide hole 15 and exerts a mechanical action on the guide member 3. Not at all.

Then, electric discharge drilling is performed while rotating the motor Mgm electrode 1 and supplying electric discharge machining power with the jig contact 6. However, the tip of the fine electrode 1 is stuck at the position of the guide member 3. Since the guide member 3 does not turn around, no pre-movement occurs, and the drilling of the workpiece 7 maintains linearity and is performed accurately.

Furthermore, since strong force is not generated between the tip of the fine electrode 1 and the guide member 3, there is no possibility that the fine electrode 1 will go into the H position or an overload will be applied to the motor M that rotates the electrode chuck 2. I don't have to worry about it.

FIG. 3 shows another embodiment, which differs from embodiment F in that the electrode gripping member 11 is formed of a resilient disk body with an electrode gripping hole 16 in the center. The thin electrode 1 is fixed by reducing the diameter of an electrode gripping hole 16 provided at the center of the disc body 11 and using its elasticity as a gripping force. Note that when a pipe electrode is used as the thin electrode 2 and machining fluid is supplied through the chuck 2, it is desirable that the disk body is made of a material with excellent oil resistance.

Furthermore, in this embodiment, since a non-metallic material is used for the electrode gripping part I411, electrical discharge machining power cannot be supplied from the chuck 2, and the inside of the guide member 3 is biased by an elastic body 12 such as a spring. A sliding contact 17 that presses against the tip of the fine electrode 1 is provided to supply electrical discharge machining power.

In the above two embodiments, the tip of the fine electrode 1 protruding from the guide member 3 is an extension of the warpage of the fine electrode 1.
Although there will be some whirling, the length δ of the protrusion is sufficiently short compared to the length of the fine electrode 1, and the guide member 3 itself does not have a pre-movement, so it is easier to use than the conventional one. In comparison, the run-out of J3 and C1 is not particularly problematic for normal discharge hole machining, such as 1-minute high machining accuracy and setting of a machining start hole.

By the way, such a discharge hole tJ device is great! i
When added as an option to an electric processing machine, is this equipment? When not in use, the guide member 3 is moved to a storage position facing the lower end of the electrode 1 dock 2, and the electric chuck 2 itself is roughly retracted from the vicinity of the upper nozzle of the Y'V 11tTi processing machine. It is configured so that it does not get in the way during wire electrical discharge machining or when removing the workpiece.

Effects of the Invention Even if the fine electrode is warped, it is possible to clearly form holes with high conductivity and high accuracy close to the diameter of the fine electrode. Further, there is no need to machine a hole with an unnecessarily large diameter, and the drilling process can improve the machining speed.

There is no possibility that the 1st electrode will be moved by I(1) and no adverse effect will be exerted on the driving means for rotating the 3rd electrode.

[Brief explanation of the drawing]

Figure 1 is a front view of the main parts shown in cross section, Figure 2 is a perspective view,
Figure 3 is a front view of main parts showing another embodiment in cross section;
The figure is a front view schematically showing a conventional technique in cross section. 1... m electrode, 2... electrode chuck, 3... guide member, 4... sleeve, 5... shaft, 6.
17...Sliding contact, 7...Workpiece, 8.11...
・Electrode gripping member, 9.16... Electrode gripping hole, 10...
- Penetration groove, 12... Spring, 13... Closing shell,
14...Catch, 15...Guide hole. Figure 4

Claims (3)

[Claims] (1) An electrode chuck that rotates a thin electrode, and a guide member that rotatably holds the tip of the thin electrode on an extension of the rotation axis of the electrode chuck, and the electrode chuck has a A discharge hole drilling device characterized in that an electrode gripping member is provided for fixing a thin electrode at an arbitrary angle. (2) The discharge hole drilling device according to claim 1, wherein the electrode gripping member is a spherical body having a diametrical electrode gripping hole. (3) The discharge hole drilling device according to claim 1, wherein the electrode gripping member is a resilient disc body and has an electrode gripping hole in the center.