JPS63207526A - Wire jam detecting guide for wire cut electric discharge machine - Google Patents

Abstract

PURPOSE:To further improve the safety, by arranging a wire jam detecting guide between a consumed electrode wire feed out mechanism and a consumed electrode wire receiving mechanism and connecting a conductive pin, mounted to said guide, to a safety circuit of a control unit through a signal wire. CONSTITUTION:A wire jam detecting guide 40 is provided in a part where an electrode wire 30, running from a wire feed out mechanism 38 to a wire receiving mechanism 41, is delivered. The consumed electrode wire 30 passes through an electric discharge machining part 36 generating improper collection in a collecting case 39, and if the wire generates turbulent running, its influence causes the wire to jam in the guide 40, resulting in the detection by a conductive pin 44 immediately transmitting a wire jam detecting signal to a safety circuit 50 through a lead wire 52. Accordingly, the safety circuit 50 immediately stops the supply of machining power to an electric discharge machine 10 interrupting the supply of a current to the consumed electrode wire 30. In this way, an accident of electric shock is prevented from its occurrence by jamming the consumed electrode wire to come into contact with a conductive element and/or its part in the periphery of a machine body.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a wire-cut electrical discharge machine, and in particular, the present invention relates to a wire-cut electrical discharge machine equipped with an automatic wire connection device. Electrically detects a wire jam that occurs near the collecting part of the consumable electrode wire that is automatically collected in the wire collecting part, detects a collecting abnormality, and quickly interrupts the supply of electric discharge machining current to prevent electric shock accidents. The present invention relates to a wire jam detection guide for a wire cut electrical discharge machine that can prevent jamming.

[Prior art]

In a wire-cut electric discharge machine, machining power is supplied to an electrode wire in an electric discharge machining section.

In other words, a discharge voltage is applied between the electrode wire and the material to be machined through a feeder, and the discharge occurs in the discharge machining section through the silk gap between the two, thereby progressing the machining. As described above, since the electrode wire is electrically conductive, a current remains in the electrode wire that passes through the electrical discharge machining section and heads toward the recovery section. For this reason, conventionally, a cover made of a non-conductive material, such as a plastic material, has been installed on the path of the electrode wire collected in the collection section to prevent workers from accidentally touching the electrode and receiving an electric shock. It is covered. - In particular, in wire-cut electrical discharge machines equipped with recent automatic wire connection devices, even when the electrode wire is cut in the electrical discharge machining section, the wire is automatically connected immediately, so the electrode wire is connected almost continuously. The electrode wire continues to travel and is always energized once it reaches the collection area. Therefore, touching the product before it is completely collected in a collection section such as a collection box poses a safety problem, and that is why an electric shock prevention cover is attached. In addition, wire-cut electrical discharge machines equipped with an automatic wire connection device keep the electrode wire running at all times to improve machining progress efficiency, thereby preventing the electrode wire from stagnation in the upper and lower sections of the electrical discharge machining section. Therefore, the electrode wire is actively fed by a heald feeding mechanism, etc. from the downstream of the electrical discharge machining section to the upstream region of the consumable electrode wire recovery section, and the consumable electrode wire feeding mechanism and the consumable electrode wire are transported in the upstream region of the recovery section. A receiving mechanism is provided to smoothly introduce the exhausted electrode wire into a collection section such as a collection box.

Therefore, a non-conductive guide for the electrode wire is provided between the consumable electrode wire delivery mechanism and the consumable electrode wire receiving mechanism.

[Problems to be solved by the invention]

However, especially in the case of a wire-cut electrical discharge machine equipped with the above-mentioned automatic wire connection device, it has the advantage that even when the electrode wire breaks, the automatic wire connection can be adjusted and electrical discharge machining can be performed continuously. When the electrode wire is being collected smoothly, the electrode wire passes smoothly through the non-conductive guide and is continuously introduced into the collection section. If a problem occurs, the electrode wire that continuously travels through the electrical discharge machining section and towards the wire collection section will become clogged at the point of the non-conductive guide just before the collection section, and the electrode wire will overflow there. When electrical current is generated and comes into contact with surrounding conductive machine body elements and parts, the current leaks into the machine body of the wire-cut electrical discharge machine, and if a person inadvertently touches the machine body, it may cause an electric shock accident. There is a point. Therefore, an object of the present invention is to completely eliminate such problems and further improve the safety of wire-cut electrical discharge machines.

[Means of solution and action]

That is, the present invention provides a wire-cut electric discharge machine in which the electrode wire travels through the electric discharge machining section to the wire recovery section, and the consumable electrode wire feeding mechanism and the consumable electrode wire receiving mechanism are provided in the upstream region of the recovery section. A wire jam detection guide is disposed between the guide member, which is made of a non-conductive material, and has an electrode wire running guide hole, and which faces the guide member's running guide hole. A wire force comprising: a conductive pin having a wire disturbance detection end and attached to the guide member; and a signal line connecting the conductive pin to a safety circuit of an electrical discharge machining control unit.・Provides a wire jam detection guide for a two-tooth electrical discharge machine, where the conductive pin quickly detects a blockage in the electrode wire, sends a detection signal to the safety circuit, and performs wire-cut electrical discharge machining according to the detection signal. This enables a safety measure to be taken to interrupt the supply of electrical discharge machining power to the machine. In other words, when the electrode wire becomes jammed, it is quickly detected and the detection signal is sent to the safety circuit in the control device of the wire-cut electrical discharge machine to control the application of machining current to the wire-cut electrical discharge machine. This is to prevent the occurrence of electric shock accidents.

Hereinafter, the present invention will be explained in more detail based on examples.

〔Example〕

FIG. 1 is a schematic front view of a wire-cut electric discharge machine equipped with a wire jam detection guide according to an embodiment of the present invention, and FIG. 2 is an enlarged cross-sectional view showing the structure of the wire jam detection guide. 3 are perspective views showing the outer shape of the wire jam detection guide.

Now, in FIG. 1, the wire-cut electrical discharge machine 10 is equipped with a column 12, a base 14, and a control device 16. A Z-axis support 18 in the vertical axis direction is provided at the tip of the column 12, and this Z-axis support 18 is provided at the tip of the column 12. The upper head 20 is mounted on the lower end of the shaft support 18 with the vertical shaft (Z
An upper wire guide 22 is provided at the lower end of the upper head 20. On the other hand, base 1
4, there are two axes (
A work table 24 movable in directions (X-axis, Y-axis) is provided, and a workpiece W is fixed onto this work table 24. Further, the tip of a lower arm 26 extending from the column 12 faces inside the work table 24, and the lower wire guide 26 is attached to the tip of the lower arm 26.
8 is attached. And electrode wire 3
0 is emitted from the supply reel 32 and guided by large and small guide rollers and brakes 34 provided on the column 12, the Z-axis support 18, the lower arm 26, etc., to the electrical discharge machining section 36.
The wire passes through the electrode wire traveling path of the lower arm 26, and then passes through a wire feeding mechanism, for example, a pair of upper and lower belt feeding mechanisms 38, to a wire collection box 39, for example.
The electrode wire reaches the immediately upstream side of the wire collection section consisting of the following, and is then removed by an electrode wire receiving mechanism, for example, a pair of feed roller mechanisms 41, via a wire jam detection guide 40, which will be described later, according to the present invention. The wire is collected in the wire collection box 39.

In the above-mentioned running system for the electrode wire 30, the running part of the consumable electrode wire 30 is likely to be damaged in the area immediately in front of the collection section due to poor collection in the wire collection box 39. If such a wire running portion misalignment occurs, wire jamming is likely to occur at the portion where the electrode wire 30 is transferred from the wire sending mechanism 38 to the wire receiving mechanism 41. Accordingly, in the present invention, such a wire hook is provided with a wire jam detection guide 40 in the transfer area that has a guiding function and is capable of detecting a wire jam at the same time. The wire jam detection guide 40 has a built-in detection pin (described later) for detecting a wire jam, and when a wire jam occurs, a wire jam detection signal is sent to a safety circuit provided in the control device 16 via a signal line 52. Send to 50. Therefore, when the safety circuit 50 receives a signal indicating a wire jam, it can stop supplying machining current to the wire-cut electrical discharge machine 10 and also stop feeding the electrode wire, thereby repairing the jam.

Now, the wire jam detection guide 40 according to the present invention is the second one.
As shown enlarged in the figure, the driving or driven roller 3 of the vertical belt feeding mechanism 3B forming the wire feeding mechanism
8, and a pair of roller mechanisms 4 forming a wire receiving mechanism.
1, and has a guide member 42 and a pair of conductive pins 44 for wire jam detection, and is fixed to the column 12 or the lower arm 2G of the fuselage by a mounting screw 48. The guide member 42 has an inner hole 54 that guides the movement of the electrode wire 30, is made of a non-conductive material such as a plastic material, and touches the electrode wire 30 on the wire running path from the outside of the guide member 42. It is impossible to do so, and there is no fear of touching it.

In this embodiment, the conductive pin 44 is connected to the inner hole 5 of the guide member 42.
If the electrode wire 30 is made of a pair of pins made of a metal material such as stainless steel and guides the inner hole 54 and runs loose due to clogging, it comes into contact with the conductive pin 44, so that the slack is immediately removed. is detected, and a signal is sent to the safety circuit 50 via a signal line 52 extending from these conductive pins 44 to the safety circuit 50 of the control device 16. Note that the conductive pin 44 may be press-fitted into the guide member 42, for example.
It is fixed using a method such as gluing.

In FIG. 2, one roller (upper roller) of a pair of rollers 41 forming a wire receiving mechanism for the electrode wire 30 is held by an arm 56 so that it can be separated from the contact position with the lower roller, if necessary. ing. 58 is a spring for pressing the upper and lower rollers 41 against each other.
FIG. 3 shows the external shape of a wire jam detection guide 40 according to the present invention having the above-described structure. It can be seen that it is a non-conductive member with concave portions formed on the left and right, top and bottom so that it can be rotated. Further, it goes without saying that the inner hole 54 may be formed to have an appropriate diameter. In order to remove the clogged electrode wire 30G, one roller 41 of the wire receiving mechanism described above may be moved to pull out the wire from inside the inner hole 54.

If the wire jam detection guide 40 having the above configuration is placed near the recovery section on the traveling path of the consumable electrode wire 30 that has passed through the electrical discharge machining section 36 (FIG. 1) of the wire-cut electrical discharge machine, the recovery box 39 When a collection failure occurs and the electrode wire 30 runs erratically, the conductive pin 44 detects the wire jam that has occurred in the guide 40 due to the influence, and a wire jam detection signal is immediately transmitted via the conductive wire 52 to ensure safety. is transmitted to circuit 50.

Therefore, the safety circuit 50 can, for example, function as a breaker and interrupt the current supply to the consumable electrode wire 30 in order to immediately stop the supply of machining power to the wire-cut electrical discharge machine 10. By taking necessary repair measures such as removing jammed wires while the current is interrupted, electric shock can be completely prevented. Note that the embodiment has been described as an example in which only the wire jam detection guide 40 according to the present invention is arranged between the wire sending mechanism and the wire receiving mechanism at the upstream position of the electrode wire 30 collection part, but the so-called automatic electrode supply In the case of a wire-cut electrical discharge machine equipped with a device or an automatic electrode connection device (AWF), the electrode wire 30 emitted from the electrode wire supply reel 32 is immediately connected even if a breakage accident occurs, and the supply continues. Therefore, when a wire jam occurs, there is a risk that the wire will overflow from the wire jam detection guide 40. In anticipation of such a situation, an electric shock prevention cover according to the patent application filed on the same day by the present applicant was installed on the outside of the guide 40. It may be left covered.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, wire clogging caused by running disturbance due to poor recovery of the electrode wire of a wire-cut electric discharge machine is electrically detected.
As a result, the supply of electric discharge machining power can be interrupted before the clogged consumable electrode wire comes into contact with conductive elements or parts around the machine body, causing an electric shock accident. The safety of electrical discharge machines, especially wire-cut electrical discharge machines with AWF, can be significantly improved. Furthermore, since the wire jam detection guide itself according to the present invention is formed as a single member with a simple structure, the safety of the wire cut electric discharge machine can be ensured at low cost (I3). be able to.

[Brief explanation of the drawing]

FIG. 1 is a schematic front view of a wire cant electric discharge machine equipped with a wire jam detection guide according to an embodiment of the present invention, and FIG. 2 is an enlarged sectional view showing the structure of the wire jam detection guide. , FIG. 3 is a perspective view showing the outer shape of the wire jam detection guide. DESCRIPTION OF SYMBOLS 10... Wire cut electric discharge machine, 12... Column, 14... Base, 16... Control device, 22... Upper wire guide, 28... Lower wire guide, 30... Electrode wire, 36... Electric discharge machining section, 40... Wire jam detection guide, 42... Guide member, 44... Conductive pin, 50... Safety circuit, 52... Conductive wire.

Claims (1)

[Scope of Claims] 1. In a wire-cut electrical discharge machine, a consumable electrode wire sending mechanism and a consumable electrode wire receiving mechanism are provided in an upstream area of the collecting section for the electrode wire traveling to the wire collecting section after passing through the electrical discharge machining section. A wire jam detection guide is disposed between a guide member that is made of a non-conductive material and has a running guide hole for the electrode wire, and a wire jam detecting guide that faces the running guide hole of the guide member. A wire cut comprising: a conductive pin having a wire disturbance detection end and attached to the guide member; and a signal line connecting the conductive pin to a safety circuit of an electrical discharge machining control unit. Wire jam detection guide for electrical discharge machines. 2. The guide member is made of a plastic material, and the conductive pin is made of a stainless steel material.
Wire jam detection guide for wire-cut electric discharge machines described in Section 1. 3. The wire cutter according to claim 1, wherein the conductive pin is composed of a pair of metal pins facing the electrode wire running guide hole of the guide member, and both pins are connected to the safety circuit. Wire jam detection guide for electrical discharge machines.