JPH0545371B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a wire-cut electric discharge machine, and in particular, to a wire-cut electric discharge machine equipped with an automatic wire connection device, the electrode wire is collected in a collection box or the like by passing through the electric discharge machining section of the wire-cut electric discharge machine. Electrically detects a wire jam that occurs near the collecting part of the consumable electrode wire that is automatically collected in the 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 electric discharge machine that can be easily detected.

[Prior art]

In a wire cut electrical discharge machine, machining power is supplied to the electrode wire in an electrical discharge machining section.
That is, a discharge voltage is applied between the electrode wire and the material to be machined through a feeder, and the discharge is performed in the discharge machining section through a narrow gap between the upper air, 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 collection section. For this reason, conventionally, a cover made of a non-conductive material, such as a plastic material, has been placed 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 connection is automatically performed immediately, so the electrode wire runs almost continuously. Subsequently, the electrode wire that has reached the collection region is also always in a energized state. 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, in a wire cut electrical discharge machine equipped with an automatic wire connection device, the electrode wire is kept in a running state at all times to improve the machining progress efficiency. The electrode wire is actively fed by a belt 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 receiving mechanism are used in the upstream region of the recovery section. A 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 upper air 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, while the above-mentioned advantage is that even when the electrode wire is broken, the wire is automatically connected and electrical discharge machining is continuously performed, When the electrode wire is being collected smoothly,
The electrode wire passes smoothly through the upper air non-conductive guide and is continuously introduced into the recovery section. However, if a problem such as entanglement of the electrode wire occurs in the electrode wire recovery section, it may cause damage to the electrical discharge machining section. The electrode wire that continuously travels through the wire toward the wire collection section becomes clogged at the point of the non-conductive guide just before the collection section, and the electrode wire overflows there, causing damage to the surrounding conductive fuselage elements, There is a problem in that if a person comes into contact with the wire-cutting electrical discharge machine, and the electric current leaks into the body of the wire-cut electrical discharge machine, and a person carelessly touches the wire-cut electrical discharge machine, an electric shock may occur. Therefore, the purpose of the present invention is to
The present invention aims to completely eliminate such problems and further improve the safety of wire-cut electric discharge machines.

[Means of solution and action]

That is, the present invention provides for an electrode wire traveling through an electric discharge machining section of a wire cut electric discharge machine to a wire recovery section to be transferred between a consumable electrode wire sending mechanism and a consumable electrode wire receiving mechanism provided upstream of the recovery section. In a wire jam detection guide for detecting a collection abnormality, a guide member made of a non-conductive material is disposed between the consumable electrode wire sending mechanism and the consumable electrode wire receiving mechanism and has a cylindrical hole for guiding the movement of the electrode wire; a conductive pin attached to the guide member and having a wire disturbance detection tip protruding perpendicularly to the traveling direction of the consumable electrode wire facing the travel guiding cylindrical hole of the guide member; and electrical discharge machining of the conductive pin. A wire clogging detection guide for a wire cut electric discharge machine is provided, characterized in that it is configured with a signal line connected to a safety circuit of a control section, and the conductive pin quickly detects clogging of an electrode wire. , a detection signal is sent to a safety circuit, and in response to the detection signal, safety processing can be performed to interrupt the supply of electric discharge machining power to the wire cut electric discharge machine. In other words, when a running jam in the electrode wire occurs, it is quickly detected and a detection signal is sent to the safety circuit in the control device of the wire-cut electric discharge machine to interrupt the supply of machining current to the wire-cut electric 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 electrical 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.

Now, in FIG. 1, the wire cut electrical discharge machine 10 includes a column 12, a base 14, a control device 16,
A Z-axis support 18 is provided at the tip of the column 12 in the vertical axis direction, and an upper head 20 is attached to the lower end of the Z-axis support 18 so as to be movable in the vertical axis (Z-axis) direction. An upper wire guide 22 is provided at the lower end of the upper head 20. On the other hand, a work table 24 is provided on the base 14 and is movable in two orthogonal axes (X-axis, Y-axis) within a horizontal plane perpendicular to the Z-axis. W is fixed. Further, the tip of the lower arm 26 extending from the column 12 faces inside the work table 24,
A lower wire guide 28 is attached to the tip thereof. Then, the electrode wire 30 is emitted from the supply reel 32 and sent to the column 12 and the Z-axis support base 1.
8. A wire feeding mechanism that allows the wire to pass through the electrical discharge machining section 36 under the guidance of large and small guide rollers and brakes 34 provided on each of the lower arms 26 and the like, and is further provided on the electrode wire travel path of the lower arm 26;
For example, the electrode wire is passed through a pair of upper and lower belt feeding mechanisms 38 to the immediately upstream part of a wire collection section consisting of a wire collection box 39, and then passed through a wire jam detection guide 40 according to the present invention, which will be described later. The wire is received by a receiving mechanism, for example, a pair of feed roller mechanisms 41, and then transferred to the wire collection box 39.
will be collected within.

In the above-described running system for the electrode wire 30, the running of the consumable electrode wire 30 tends to be disturbed in the area immediately in front of the collecting section due to poor collection in the wire collecting box 39. When such wire running disorder occurs, wire jamming is likely to occur at the portion where the electrode wire 30 is routed from the wire sending mechanism 38 to the wire receiving mechanism 41. Therefore, in the present invention, a wire jam detection guide 40 is provided in such a wire spanning area, which has a guiding function and can detect wire jams at the same time. This 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 detection signal of the wire jam is sent to a safety circuit provided in the control device 16 via a signal line 52. Send to 50. Therefore, the safety circuit 50 is
When a wire clogging signal is received, the supply of machining current to the wire-cut electric discharge machine 10 is stopped, and the feeding of the electrode wire is also stopped, so that the clogging can be repaired.

Now, the wire jam detection guide 4 according to the present invention
0 is provided between the driving or driven roller 38 of the vertical belt feeding mechanism 38 forming the wire feeding mechanism and a pair of roller mechanisms 41 forming the wire receiving mechanism. , a guide member 42, and a pair of conductive pins 44 for wire jam detection, and is fixed to the column 12 or lower arm 26 of the machine body with a mounting screw 48. The guide member 42 is provided with an inner hole 54 for guiding the running 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 has become impossible to do so, and there is no fear of touching it. Conductive pin 44
In this embodiment, the pin is made of a pair of metal material, for example, stainless steel, and faces the inner hole 54 of the guide member 42. If the electrode wire 30 that guides and runs through the inner hole 54 is loosened due to clogging, , since it comes into contact with the conductive pins 44, it immediately detects the slack and sends a signal to the safety circuit 50 via the signal line 52 extending from the conductive pins 44 to the safety circuit 50 of the control device 16. In addition, conductive pin 4
4 is fixed to the guide member 42 by, for example, press-fitting, gluing, or the like.

In FIG. 2, one roller (upper roller) of a pair of rollers 41 forming a wire receiving mechanism for the electrode wire 30 is attached to an arm 56 so that it can be separated from the contact position with the lower roller, if necessary.
is held in 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 stuck electrode wire 30, one roller 41 of the wire receiving mechanism described above may be moved to pull out the wire from inside the inner hole 54.

Wire jam detection guide 4 consisting of the above configuration
Electric discharge machining section 36 of a wire-cut electric discharge machine
(Fig. 1), if the consumable electrode wire 30 is disposed near the circuit section on the traveling path of the consumable electrode wire 30 that has passed through the consumable electrode wire 30 (Fig. The conductive pin 44 detects a wire jam that occurs in the wire 40, and a wire jam detection signal is immediately transmitted to the safety circuit 50 via the conductive wire 52.

Therefore, the safety circuit 50 can, for example, act as a breaker to interrupt the supply of current to the consumable electrode wire 30 in order to immediately stop the supply of machining power to the wire-cut electrical discharge machine 10. If necessary repair measures such as removing jammed wires are taken during the current interruption, complete prevention of electric shock can be achieved. In addition, in the embodiment, between the wire sending mechanism and the wire receiving mechanism at the upstream position of the collection part of the electrode wire 30,
Although the explanation has been given as an example in which only the wire jam detection guide 40 according to the present invention is arranged, in the case of a wire cut electric discharge machine equipped with a so-called automatic electrode supply device or automatic electrode wire connection device (AWF), the electrode wire supply reel 32 Electrode wire 3 generated from
0, even if a disconnection accident occurs, the wire is immediately connected and the supply continues, so if a wire jam occurs, there is a risk that the wire will overflow from the wire jam detection guide 40. In consideration of such a situation, An electric shock prevention cover according to a patent application filed on the same day by the present applicant may be attached to the outside of the guide 40.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, the guide made of a non-conductive material is provided between the consumable electrode wire sending mechanism and the consumable electrode wire receiving mechanism at the front stage of the electrode wire collection area of a wire cut electrical discharge machine. A conductive pin with a wire disturbance detection end facing perpendicularly to the cylindrical hole for guiding the movement of the member electrically detects a wire jam caused by the running disorder of the consumable electrode wire, thereby removing the clogged consumable power wire. By interrupting the supply of electrical discharge machining electrodes before they come into contact with conductive elements or parts around the machine and causing an electric shock accident, we are able to repair any failures.
The safety of wire-cut electrical discharge machines, especially wire-cut electrical discharge machines with AWF, can be significantly improved. Further, since the wire jam detection guide itself according to the present invention is formed as a single member with a simple structure, it is possible to obtain the effect that the safety of the wire cut electric discharge machine can be ensured at low cost.

[Brief explanation of the drawing]

FIG. 1 is a schematic front view of a wire cut electrical 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 wiper clogging detection guide. DESCRIPTION OF SYMBOLS 10... Wire cut electrical discharge machine, 12... Column, 14... Base, 16... Control device, 22...
...Upper wire guide, 28...Lower wire guide, 3
0... 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. An electrode wire traveling to a wire recovery section after passing through an electrical discharge machining section of a wire cut electric discharge machine is transferred between a consumable electrode wire sending mechanism and a consumable electrode wire receiving mechanism provided upstream of the recovery section. A wire jam detection guide for detecting a recovery abnormality includes: a guide member made of a non-conductive material, disposed between the consumable electrode wire sending mechanism and the consumable electrode wire receiving mechanism, and having a cylindrical hole for guiding the electrode wire; , a conductive pin attached to the guide member and having a wire disturbance detection tip protruding perpendicularly to the traveling direction of the consumable electrode wire facing the travel guiding cylindrical hole of the guide member; and discharging the conductive pin. A wire jam detection guide for a wire cut electrical discharge machine, characterized in that it is configured to include a signal line connected to a safety circuit of a processing control section. 2. The wire jam detection guide for a wire cut electrical discharge machine according to claim 1, wherein the guide member is made of plastic material and the conductive pin is made of stainless steel material. 3. The conductive pin comprises a pair of metal pins facing each other facing the electrode wire running guide hole of the guide member, and both metal pins are both connected to the safety circuit. Wire jam detection guide for wire cut electrical discharge machines described in Section 1.