JPS6347022A - Wire-cut electric discharge machine - Google Patents

Abstract

PURPOSE:To prevent a dielectric fluid in a work tank from leaking without enlarging a device, by constituting a shielding body, sealing a clearance between an opening peripheral edge of the long hole formed in a side wall of the work tank and an arm, so as to be wound at both sides of the said long hole. CONSTITUTION:At the time of machining, if a lower arm 5 is relatively moved in an x direction with horizontal movement of a work tank 2, a shielding body 32 is also moved in the same direction and wound or rewound to or from a winding part at both sides. At the time of movement to a Y direction of the lower arm 5, this arm 5 is slidden along a fitting hole of a seal body 34 on the shielding body 32. Therefore, a clearance between an opening peripheral edge of the long hole 21 installed in a side wall of the work tank 2 is kept in a sealed state at all times, whereby a dielectric fluid L inside the work tank 2 can be surely prevented from leaking out of the clearance. In addition, since the shielding body 32 is wound by the winding part, enlargement of a device is prevented.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention generates electrical discharge between a continuously supplied wire electrode and a workpiece, and processes the workpiece using the discharge energy. The present invention relates to a wire-cut electric discharge machine.

[Prior Art] Conventionally, a wire-cut electric discharge machine uses an immersion method in which a workpiece is placed in a machining tank filled with machining fluid, and the wire electrode and the machining tank are moved relative to each other to perform machining. Types of this type are known, in which an arm having an electrode guide for guiding a wire-electrode is inserted through an opening formed in the processing tank toward the workpiece. When the processing tank and the wire electrode are moved relative to each other during processing of the workpiece, the arm is moved in the longitudinal direction so that the processing liquid in the processing tank does not leak to the outside through the opening. There is a method in which a seal plate larger than the opening is provided, which is slidably inserted through the processing tank and is disposed so as to be movable relative to the processing tank, and the opening is sealed with the seal plate.

[Problems to be Solved by the Invention] As described above, in a device that seals an opening with a seal plate larger than the opening, it is difficult to maintain a complete seal even when the arm is relatively moved to one end of the opening. In order to hold it, it is necessary to prepare a plate that is quite large in relation to the opening, and the processing tank in which the plate is placed needs to be very large, which not only increases the size of the equipment but also increases the cost. There was a point.

[Object of the invention] The present invention solves the above-mentioned problems, and provides a wire-cut electric discharge machine that can reliably prevent machining fluid from leaking in the machining tank without increasing the size of the device. The purpose is to provide.

[Means for Solving the Problems] In order to achieve the above object, in the present invention, an arm having an electrode guide for guiding the wire electrode is formed in a substantially horizontal direction on the side wall of the processing tank. Winding portions at both ends of a flexible strip-shaped shield placed through the hole and provided with a fitting hole approximately in the center are supported by the side walls on both sides of the elongated hole, and An intermediate portion between both winding portions is slidably supported on the side wall.

[Function] With the above-described configuration, when the arm is moved horizontally relative to the processing tank, the shield is pulled out from one winding part of the shield, and the other winding part is pulled out. The intermediate portion between the two winding portions ensures that the gap between the opening periphery of the long hole in the processing tank and the arm is always sealed against the side wall of the processing tank.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

Now, in the wire-cut electric discharge machine of this embodiment, as shown in FIG. It is possible to support the workpiece W in a state where the space is filled. An upper arm 3 is provided on the frame 1 above the processing tank 2, and an upper electrode guide 4 made of a conductive roller is supported at the lower part of the upper arm 3 so as to be movable in the vertical direction. The frame 1 is arranged so as to penetrate the side wall of the processing tank 2 and extend horizontally to a position below the workpiece W.
A lower arm 5 made of a conductive cylindrical body projects from the side of the frame 1 in an insulated state, and a lower electrode guide 6 made of a conductive roller is attached to the tip of the lower arm 5.
It is supported in an insulated state.

A feeding device 8 for feeding a wire electrode 7 made of a metal wire is provided at the top of the frame 1, and a winding device 9 for winding up the wire electrode 7 is provided at the bottom of the frame 1. . And supply device 8
The wire electrode 7 fed out from the electrode guide 4 is guided to the winding device 9 through the guide roller 10, the upper electrode guide 4, the lower electrode guide 6, and the guide roller 11, and is placed on the workpiece W between the electrode guides 4 and 6. It is supplied continuously.

A power supply circuit is connected between the wire electrode 7 and the workpiece W, and both 7. Pulse discharge is repeatedly generated in the machining gap between W, and the workpiece W is machined by the discharge energy.

That is, in the power supply circuit, one terminal of the DC power supply 12 is connected to the source terminal of the field effect transistor 13, and the switching control circuit 14 for controlling the switching operation of the transistor 13 is connected to the gate terminal thereof.
is connected. A diode 15 and a resistor 16 are connected between the train terminal of the transistor 13 and the other terminal of the power supply 12 to eliminate reactance caused by the switching operation of the transistor 13.

The workpiece W is connected to the ground side terminal of the power supply circuit via the conductive lower arm 5, and the wire electrode 7
is connected to the other terminal of the power supply circuit via the lower electrode guide 6.

Further, a pump 17 is connected to the lower arm 5, and the operation of this pump 17 fills the machining liquid from the machining liquid tank through the inside of the lower arm 5 into the machining tank 2 at the start of work, and fills the machining liquid into the machining tank 2 during machining work. In this case, machining liquid can be supplied to the machining gap between the wire electrode 7 and the workpiece W.

Next, the seal structure of the lower arm penetrating portion of the processing tank 2 and the internal structure of the lower arm 5, which are the main parts of the present invention, will be explained in detail based on FIGS. 2 to 6.

Now, in this embodiment, on one side of the processing tank 2,
A long hole 21 for inserting the lower arm 5 is formed near the lower end of the side wall so as to extend substantially horizontally, and accommodation recesses 22 are formed on the outer surface of the side wall of the processing tank 2 on both left and right sides of the long hole 21. It is formed. A groove 23 is formed on the soil surface of the bottom wall of the machining tank 2 so as to extend outside the long hole 21 and along the long hole 21, and to catch and stop leakage water from the machining tank 2. A drain port 24 is formed in the side wall of the processing tank 2 in communication with one end.

A guide plate 25 is attached to the outer surface of the side wall of the machining tank 2 in correspondence with the long hole 21, and an opening 26 is formed approximately in the center of the guide plate 25 in correspondence with the long hole 21. And 2.3
．． As shown in FIG. 5, a pair of guide grooves 27 are formed on the outer surface of the side wall of the processing tank 2 by the guide plate 25, and extend horizontally along the upper and lower sides of the elongated hole 21.

A pair of upper and lower support plates 28 are attached to the inner surfaces of the left and right sides of the guide plate 25, respectively, and are arranged to protrude into the accommodation recess 22 of the processing tank 2. A take-up reel 29 is rotatably supported between the pair of upper and lower support plates 28 in both housing recesses 22 . In this embodiment, each take-up reel 29 is composed of a pair of upper and lower discs 30 and a rotating shaft 31 that is fitted and fixed to the discs 30.

A flexible strip-shaped shield 32 is wound and supported on both the winding reels 29 at winding portions at both left and right ends, and the intermediate portion between the winding portions is connected to the elongated hole 21 of the processing tank 2. Information board 25
The guide groove 27 is slidably inserted and supported between the opening 26 and the guide groove 27 .

A seal body 34 is fitted into a through hole 33 formed approximately at the center of the shield body 32, and a fixing plate 35 is fitted to the inner end of the seal body 34 while sandwiching the shield body 32.
It is fixed to the periphery of the through hole 33 by screwing a plurality of screws 36 into the hole 33 .

A fitting hole 37 for slidably fitting the lower arm 5 is formed in the center of the seal body 34, and a packing 38 that tightly contacts the outer circumferential surface of the lower arm 5 is provided on the inner periphery of the fitting hole 37. .

In this embodiment, the shielding body 32 is the fifth
As shown in the figure, the shield 32 has the property of curving outward at its center in the width direction, and based on this, both upper and lower edges of the shield 32 are tightly engaged with the guide groove 27 . Therefore, the gap between the opening periphery of the long hole 21 of the processing tank 2 and the lower arm 5 is always kept in a sealed state by the shield 32. In addition, the shielding body 32 has the property of being wound at each winding portion by its own elastic force, and when the shielding body 32 is moved relative to the processing tank 2, one winding portion is wound. While being unwound, the other winding portion is wound up by its own elastic force.

On the other hand, as shown in FIG. 6, at the outer end of the lower arm 5 made of a conductive cylindrical body, there is an end plate 3 made of an insulating material.
9 is fitted and fixed by a plurality of screws 40, and
Inside the lower arm 5 are a plurality of support plates made of insulating material.
41 are arranged at predetermined intervals, and a plurality of holding rods 42 are installed between the support plate 41 located at the innermost side (on the right side in FIG. 6) and the end plate 39. A wire guide vibe 43 is supported through the end plate 39 and the support plate 7111 so as to extend in the longitudinal direction at the lower part of the lower arm 5.
The wire electrode 7 can be inserted and guided. A power supply line 44 is supported through the end plate 39 and the support plate 41 so as to extend in the longitudinal direction near the center of the lower arm 5. Power is supplied to the wire (7-electrode 7) through this power supply line 44. It is supposed to be done.

Also, an end plate 39 and a support plate/! extend in the longitudinal direction near the other side of the center in the lower arm 5. A water supply pipe 45 is supported through the pipe 41, and the water supply pipe 45 is supported during processing work.
The machining liquid l- is supplied to the machining gap between the wire electrode 7 and the workpiece W through the wire electrode 5. A supply pipe 46 is supported through the end plate 39 at the upper part of the outer end of the lower arm 5, and when starting work, etc.
6 supplies machining fluid into the lower arm 5, and fills the machining tank 2 with the machining fluid through a guide passage formed by the inner wall of the lower arm 5.

Furthermore, as shown in FIG. 5, a conductive bracket 48 is attached to the inner end of the lower arm 5 through an insulating plate 47, and the lower electrode guide 6 is rotatably attached to the tip of the bracket 1. It is supported so as to guide the wire electrode 7 around it. On the bracket 48 are a pair of cylindrical bodies 49.5 for inserting the electrode 7 into the wire.
A guide hole 51 for guiding the electrode 7 to the wire is provided inside the bracket 4. A fitting hole 52 is formed in a part of the bracket 4. Fitting hole 5
The inner end of a power supply line /14 is fitted into the power supply line 2, and power is supplied to the wire electrode 7 from the power supply line /14 via the bracket 48 and the lower electrode guide. or,
A connection port 53 is formed on the bracket 48, and the inner end of the water supply pipe/15 or the coupling 5 is connected to the connection port 53.
4, and machining liquid is supplied from the water supply pipe 45 to the machining gap via the communicating passage 55, 56 of the bracket 48 and the cylindrical body 49 that acts as a nozzle. .

Therefore, during machining with this wire-cut electric discharge machine, as the machining tank 2 moves in the horizontal direction, the lower arm 5 moves to the third position.
When the shielding body 32 is relatively moved in the X direction in the figure, the shielding body 32 is also moved in the same direction and is wound up or unwound by the winding portions at both ends, and
When the lower arm 5 moves in the Y direction, the lower arm 5 is slid along the fitting hole 37 of the seal body 34 on the shielding body 32. For this purpose, the gap between the opening periphery of the elongated hole 21 provided in the side wall of the processing tank 2 and the lower arm 5 is always kept in a sealed state by the M shield 32, and the processing tank is It is possible to reliably prevent the machining fluid inside the container from leaking.

Further, in this embodiment, the lower arm 5 is formed of a conductive cylindrical body and is connected to the ground side terminal of the power supply circuit, and a wire electrode 7 is provided inside the lower arm 5.
is inserted and guided, and a power supply line 44 for connecting the other terminal of the power supply circuit is inserted and arranged through the wire electrode 7, so that the noise is absorbed by the lower arm 5 and the noise is transmitted to the outside. It is possible to prevent leakage.

It should be noted that the present invention is not limited to the configuration of the above-mentioned embodiments, and the configuration of each part can be arbitrarily changed and embodied without departing from the spirit of the invention.

[Effects of the Invention] As detailed above, the present invention includes winding a shield on both sides of the elongated hole to seal the gap between the arm and the opening periphery of the elongated hole formed in the side wall of the processing tank. I did it like this,
This has the effect of reliably preventing the machining fluid in the machining tank from leaking without increasing the size of the device.

[Brief explanation of drawings]

FIG. 1 is a partial cross-sectional view showing an outline of a wire-cut electrical discharge machine embodying the present invention, FIG. 2 is a partially cut-away rear view showing an enlarged view of the machining tank, and FIG. 4 is a partially enlarged sectional view taken along line B-B in FIG. 2; FIG. 5 is a partially enlarged sectional view taken along line C-C in FIG. Fig. 6 is a partially enlarged cross-sectional view showing the lower arm cut along the axis of the internal pipes, etc. 2 is a machining tank, 5 is a machining arm, 6 is a machining electrode guide, 7
21 is a wire electrode, 21 is a long hole, 27 is a guide groove, 32 is a shielding body, 34 is a sealing body, 37 is a fitting hole, and W is a workpiece.

Claims (1)

[Claims] 1. A wire that generates electrical discharge between a continuously supplied wire electrode (7) and a workpiece (W) and processes the workpiece (W) using the discharge energy. The cut electric discharge machine includes a machining tank (2) that supports the workpiece (W), and a long hole (2) formed in the side wall of the machining tank (2) in a substantially horizontal direction.
1) and extends toward the workpiece (W),
an arm (5) arranged to be movable horizontally relative to the processing tank (2) and having an electrode guide (6) for guiding the wire electrode (7); and windings at both ends. The part is supported by the side wall of the processing tank (2) on both sides of the elongated hole (21), and the intermediate part between both of the winding parts is supported slidably with respect to the side wall, and the part is supported approximately in the center by the side wall of the processing tank (2). A flexible strip-shaped shield (32) is provided with a fitting hole (37) for slidably fitting the arm (5), and the shield (32) is used for processing. Long hole (21) in tank (2)
A wire-cut electric discharge machine characterized in that the gap between the opening periphery of the arm (5) and the arm (5) is sealed. 2. The arm (5) is formed of a cylindrical body, into which the wire electrode (7) is inserted and guided, and a power supply line (
44), the inner wall of which forms a guide passage for supplying or discharging machining fluid to the machining tank (2). Processing machine. 3. The arm (5) is formed of a cylindrical body, is insulated from the frame (1) and connected to the ground terminal of the power supply, and the wire electrode (7) is inserted and guided inside the arm (5). A wire cut according to claim 1, characterized in that a power supply line (44) for connecting the other terminal of the power source is inserted through the wire electrode (7). Electric discharge machine.