JPS5837545Y2 - Electrolytic pretreatment equipment for wire electrodes - Google Patents

Description

[Detailed description of the invention] The present invention is applied to an electrolytic pretreatment device for a wire electrode in a wire-cut electric discharge machining machine that processes a workpiece by passing a machining current through the gap between a wire electrode that moves in the axial direction and a workpiece facing the workpiece. It is something.

When performing wire cut electrical discharge machining, the wire used for this is usually a metal 9 alloy thin wire with a diameter of about 0.05 to 0.5 mm, but the surface of this thin wire has a few micrometers due to the wire drawing during manufacturing. There may be some swelling or scale may be attached.

Therefore, if such a thin wire is used for processing, burrs and scales may fall off and adhere to the guide surface or guide roller surface, impairing the smooth movement of the wire electrode, or causing damage to the processing gap between the workpiece and the workpiece. This has the drawback of causing arcs, short circuits, disconnections, etc., and interfering with electrical machining aimed at high precision and high speed.

The present invention was devised to improve the above-mentioned drawbacks, and by energizing the wire electrode as an anode before the wire electrode is drawn out from the storage drum that stores the wire electrode and sent to the processing gap. , relates to an improvement of the invention described in, for example, Japanese Patent Publication No. 52150896, which removes burrs and scales attached to wire electrodes, and by removing burrs more reliably, arcs, short circuits, and even disconnections can be prevented. This not only prevents wire cutting but also enables desired electrolytic deburring without interfering with the running or tension of the wire electrode, thereby making it possible to perform high-precision and high-speed wire-cut electric discharge machining.

Furthermore, in Japanese Patent Application Laid-open No. 52-20499 by the same applicant as the present invention, a treatment tank is provided at a position through which the wire electrode moves before reaching the machining gap, in which the surface of the wire electrode is purified by electrochemical action. There is a description of a wire-cut electric processing device, which has a plurality of current-carrying electrodes in a processing tank filled with an electrolytic solution, and conducts current between these electrodes and passes the wire electrode. The surface is purified by acting as an intermediate electrode.

The present invention is a further improvement of such a device, in which a cylindrical cathode is immersed in a pretreatment tank, and a wire electrode is coaxially moved through the cylindrical electrode. The wire electrode is used as an anode to conduct electricity.

Therefore, compared to the device described in the above-mentioned publication, the anodic dissolution action can be applied directly and uniformly to the entire circumferential surface of the wire electrode, so that even greater surface purification effects can be expected for the wire electrode. It is.

The present invention will be explained below with reference to one embodiment of the drawings.

FIG. 1 is an explanatory diagram of the configuration of an embodiment of the present invention, and FIG. 2 is a layout diagram of the embodiment of the present invention.

In FIG. 1, 1 is a wire electrode, 2 is a storage drum for storing the wire electrode 1, 3 is a tensioning device for applying tension to the wire electrode consisting of pinch rollers 3a and 3b, and 4 is electrolytically processed inside. This is a wire electrode 1 electrolytic pretreatment processing tank filled with liquid and having an opening at the top.

Reference numeral 5 designates a guide roller for introducing the wire electrode 1 into the processing tank, and reference numeral 6 designates a guide roller for leading out the wire electrode 1.

Reference numeral 7 denotes a guide roller that also serves as a current-carrying electrode made of a conductive material for moving the wire electrode 1 introduced into the processing tank along a U-shaped path; 8 refers to a guide roller that circulates an electrolytic processing fluid in the processing tank; A machining fluid storage tank for supplying the machining fluid, which is injected from the lower part of the machining tank by a pump P through a filter F, and has a circulation path that returns to the machining fluid storage tank 8 through a pipe 9 from an overflow opening in the upper part. is forming.

Reference numeral 10 is provided facing the machining liquid so as to coaxially surround the introduction path and the derivation path of the wire electrode introduced into the processing tank 4 and guided and moved along the U-shaped path, and having an overall side surface shape. is an electrode for electrolytic processing having an H-shaped configuration.

11 is a DC power supply for electrolytic pretreatment processing, and if necessary, a pulse current blocking reactor L for preventing the pulsed current for wire cut electric discharge machining from flowing back into the DC power supply 11;
Other high frequency circulation prevention means are provided at the output.

Then, with the polarity as shown in the figure, direct current is applied between the wire electrode 1 and the H-shaped electrode via the guide roller which also serves as the electrode.

12 is a drum for winding the wire electrode, and a pinch roller 13
constant speed transfer device 13 consisting of a and capstan 13b
Winding is performed at a constant speed.

Reference numeral 14 denotes a pressure gas jet nozzle for removing the electrolytic machining fluid adhering to the wire electrode led out from the inside of the machining tank. If pure water having the same quality or the same electric resistance of 102 to 10105Q as the machining fluid supplied to the machining gap is used, there will be almost no adverse effects due to the mixing of the two fluids, but if the machining fluid is used in the machining tank 4, the machining fluid with a stronger electrolytic property will be used. It is necessary for maintenance and management of other movable parts of the equipment.

15 is a workpiece, 16 is a machining fluid supply nozzle for wire-cut electrical discharge machining, and 17 is a nozzle for generating intermittent pulsed discharge with polarity as shown in the figure in the machining gap between the workpiece 15 and the wire electrode 1. This is a pulse power source for electrical discharge machining.

Note that 18 is a pair of arms extending from the column and having a pair of guides 18 a and 18 b for feeding the wire electrode into the processing gap.

FIG. 2 is a layout diagram of an embodiment of the present invention, in which the same reference numerals as those in FIG. 1 represent the same parts.

In the figure, 20 is the bed of the wire-cut electric discharge machining machine, and 21
represents a wire electrode electrolytic pretreatment device, which device is in particular located in the path of the wire electrode between the storage drum 2 and the processing nip.

Reference numeral 22 denotes a column that stands on the bed 20 or on the side of the bed, and has a storage drum 29 and a winding drum 12 on one side, such as the inside or the front. Wire electrode pretreatment device 21. Contains other devices.

23 is a processing table, a clamping means 24 for the workpiece 15,
It also has a motor M12M2 for movement in the X-axis direction and Y-axis direction.

As mentioned above, since the wire electrode pretreatment device 21 is located in the wire electrode path between the storage drum 2 and the tensioning device 3, the wire electrode pretreatment device 21 is located in the wire electrode path between the tensioning device 3 and the constant speed transfer device
Wire electrode between 1. That is, there is no effect on the transfer state or tension of the wire electrode 1 that is transferred through the machining gap, and highly accurate machining can be performed using the wire electrode from which foreign substances such as burrs and scales have been removed.

In the above configuration, when the constant speed transfer device 13 is driven to wind the wire electrode onto the winding drum 12, a desired tension is applied to the wire electrode by the action of the tension applying device 3, and wire cut discharge occurs. Before reaching the processing gap, the wire electrode moves along a U-shaped path in the electrolytic pretreatment processing tank 4.

Then, by applying direct current, pulsed current, or alternating current for electrolytic processing between the H-shaped electrode 10 and the wire electrode 1, the scale or scale on the surface of the wire electrode 1 can be completely removed by the anodic dissolution action.

Next, the wire electrode 1 subjected to electrolytic pretreatment is supplied to a wire cut electric discharge machining gap.

In this discharge machining gap, the wire electrode 1 is connected to the power source 17.
By performing intermittent pulsed discharge using the machine as a cathode and the workpiece as an anode, high precision and high speed wire cut electrical discharge machining can be performed.

Although the outline of the present invention has been explained with reference to the configuration explanatory diagrams and the layout diagrams of the embodiments shown above, various changes and configurations can be made to each part in implementing the invention, as well as additions.

For example, a part of the wire-cut electric discharge machining power source 17 can be used as the electrolytic machining power source in the machining tank 4.

There is usually a relatively long wire electrode path between the wire cut electrical discharge machining section and the wire electrode electrolytic pretreatment section, and the electrical resistance between them is relatively high, so this rarely poses a problem. If the voltage is short and the electrical resistance is low, or if the polarity of the machining voltage is switched in the discharge gap or how the power supplies 17 and 11 are grounded, a short circuit may be formed. Care must be taken to ground guides, rollers, etc. that come into contact with the wire electrode, and to provide means for preventing circulation of high-frequency (processing pulse) current.

The power source 11 is of course provided with voltage and current adjustment means, as well as switching the transfer speed of the wire electrode 1.

Even if there is a change in the wire diameter or material, the wire electrode is changed so that the desired deburring and scaling can be done more reliably and uniformly around the entire circumference of the wire electrode. Since the diameter of the wire electrode is small, the diameter of the wire electrode is small, so that electrolytic deburring can be carried out in opposite directions over the length region, It may be a pair of opposing electrodes having opposing surfaces arranged to face the wire electrode in a perpendicular direction as a line of symmetry, and the wire electrodes are energized not from the guide roller 7 but at a position outside the processing tank 4. An energized brush, a roller, etc., and an insulating material as the roller 7.
It can also be used as a fixed sliding guide, and the upper opening of the electrolytic processing tank is closed leaving an opening for introducing and leading out the wire electrode.

As described above, in the present invention, the surface of the wire electrode for wire-cut electrical discharge machining is subjected to electrolytic processing before being supplied to the electrical discharge machining gap, so that the oxides generated due to wire drawing and other causes during the manufacturing of the wire electrode are removed. It is capable of cleanly removing scales such as, etc., and enables processing with higher precision and higher speed than conventional processing equipment of this type, but it has the configuration described in the above-mentioned utility model registration claim. This makes it possible to perform reliable and sufficient pretreatment on only the areas that require pretreatment to remove burrs, scale, etc., immediately before wire-cut electric discharge machining. The machining operation and operation of the wire-cut electrical discharge machining section can be performed without affecting the entire machining operation and operation, thereby making it possible to truly perform the above-mentioned high-precision machining in a stable state without wire breakage or the like.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the configuration of an embodiment of the present invention, and FIG. 2 is a layout diagram of the embodiment of the present invention. In the figure, 1 is a wire electrode, 2 is a wire electrode storage drum, and 3
1 is a device for applying tension to the wire electrode, 4 is a wire electrode electrolytic pretreatment processing tank, 8 is an electrolytic processing liquid storage tank, 10 is an electrode for electrolytic processing, 11 is a power source for electrolytic processing, 12 is a wire electrode winding drum, 13 is a constant speed transfer device, 15 is a workpiece, 1
7 is a power supply for wire cut electrical discharge machining.

Claims (3)

[Scope of utility model registration request] (1) In a wire-cut electrical discharge machining device, a wire electrode passage path between a drum that stores wire electrodes and a brake drum that is provided to apply tension to the wire electrodes that are pulled out from the drum and supplied to the processing section. A pre-treatment processing tank for the wire electrode filled with an electrolytic processing liquid and having an opening at the top is provided nearby, and a circulating supply device for the electrolytic processing liquid to the processing tank, and a pre-treatment processing tank for the wire electrode filled with an electrolytic processing liquid and having an opening at the top. a pair of rollers provided outside the processing tank for guiding the wire electrode into the processing tank and guiding it out; and at least one roller provided inside the processing tank for guiding the wire electrode introduced into the processing tank along a U-shaped path. a cylindrical current-carrying electrode provided so as to coaxially surround the wire electrode in one or both of the introduction part and the lead-out part of the U-shaped path of the wire electrode moving in the processing tank; ,
An apparatus for electrolytic pretreatment of a wire electrode, characterized in that a power source for electrolytic pretreatment of a wire electrode is provided between the current-carrying electrode and the wire electrode, the power source being connected with the current-carrying electrode as a cathode. (2) The electrolytic pretreatment device for wire electrodes according to claim 1, wherein a wire cut electric discharge machining fluid is used as the electrolytic/1st shift Loe fluid. (3) A utility model registration claim characterized in that the outlet section is provided with a pressurized gas blowing device for removing the electrolytic working fluid adhering to the wire electrode led out from the pretreatment tank. An electrolytic treatment device for wire electrodes according to scope 1.