JPH0540894Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Field of Application) This invention relates to a wire-cut electric discharge machine that has an improved seal structure in a machining tank that allows a workpiece to be immersed in a machining fluid.

(Prior Art) An example of a conventional wire-cut electric discharge machine is the one disclosed in Japanese Patent Application Laid-Open No. 61-294218.

As shown in FIGS. 2 and 3, in one side of the processing tank 2 in which the workpiece can be immersed in the processing liquid, a wire electrode is connected to the outside from the processing tank 2 near the lower end of the side wall. A long hole 21 through which an arm 5 (not shown) is inserted is formed to extend substantially horizontally, and a steel housing 25 is wound around the outer surface of the side wall of the processing tank 2 on both sides of the long hole 21. Each is provided.

A pair of upper and lower presser plates 28 are hung between both steel housings 25 attached to the outer surface of the side wall of the processing tank 2 on both sides of the elongated hole 21. Long hole 21
A pair of guide grooves 27 are formed that extend horizontally along the upper and lower sides.

As shown in FIG. 3, the steel housing 25
A storage recess 22 is formed inside the storage recess 22, and a cylindrical winding roller 29 is rotatably supported within this storage recess 22. This winding roller 29
The upper and lower rotating shafts 31 are supported by the lower and upper walls of the accommodation recess 22 in the steel housing 25, and as shown in FIG. A housing bush 30 is interposed between the two.

A shielding body 32 made of a flexible band-shaped steel seal is wound around and supported by the winding rollers 29 on both the left and right sides, and the intermediate portion of this shielding body 32 is connected to the processing tank 2. The guide groove 27 is slidably inserted and supported within the guide groove 27 formed on the outer surface of the side wall and the step portion 41 of the upper and lower presser plates 28 . In addition,
As shown in FIG. 3, a packing 40 is attached to the side wall of the stepped portion 41. As shown in FIG.

A through hole 33 through which the arm 5 is inserted is formed approximately in the center of the shield 32, and in order to seal this portion, the shield 32 at the through hole 33 is sandwiched from both sides. , the seal receivers 34A, 34B are attached with screws 36,
Fitting hole 3 provided in seal receivers 34A, 34B
A ring-shaped pipe seal 38 made of a non-ventilated closed-cell foam material is provided on the inner periphery of the arms 5 and 37 in close contact with the outer peripheral surface of the arm 5. In addition,
In FIG. 3, the pipe seal 38 is shown removed from the fitting hole 35.

The shielding body 32 is supported at its center in the width direction so as to curve and protrude further inside the processing tank 2 than its upper and lower side edges. In addition, the shield 32
has the property of being wound around the winding roller 29 forming the winding part by its own elastic force, and the shielding body 3
When 2 is moved relative to the processing tank 2, it is unwound at one winding part, and wound up at the other winding part by its own elastic force.

Therefore, when the arm 5 moves in the X direction in FIG. By performing the unwinding, the elongated hole 21 can be always covered while sliding in the guide groove 27.

Further, when the arm 5 moves in the Y direction in FIG. 3, the pipe seal 38 provided on the seal receivers 34A and 34B allows the arm 5 to move while maintaining a sealed state.

(Problems to be solved by the invention) However, in the above conventional example, when machining powder generated by electrical discharge machining is generated in the machining tank 2,
Processing powder adheres to the inside of the guide groove 27, and since the packing 40 attached to the side wall of the guide groove 27 is made of the same material as the pipe seal 38, adhesion does not occur. The processed powder does not fall off easily, and the shielding body 32 in the guide groove 27
It is conceivable that the sliding resistance will increase and the sealing performance will deteriorate.

(Means for solving the problem) In order to solve the above problem, the wire cut electric discharge machine of the present invention stores the workpiece inside,
A processing tank for immersing the workpiece in a processing liquid, a long hole formed to extend along the side wall of the processing tank, and a guide groove provided above and below the long hole;
A wire-cut electric discharge machine comprising: a band-shaped shield that is slidably supported by the guide groove and covers the long hole; and a sliding means that slides the shield according to the guide groove. A fluororesin layer is formed over the entire sliding area of both inner surfaces of the guide groove facing the upper and lower sides of the strip-shaped shield.

(Function) The wire-cut electrical discharge machine of the present invention having the above-mentioned configuration has a strip-shaped shield formed by forming a fluororesin layer over the entire sliding area of the upper and lower sides and both inner surfaces of the guide groove facing each other. The processed powder does not adhere to the surface, and the sliding surface between the guide groove and the shield is always kept clean, and an increase in sliding resistance can be prevented. Therefore, it is also possible to prevent deterioration of sealing performance.

Furthermore, since fluororesin has excellent electrical insulation properties, it is possible to prevent electrolytic corrosion caused by electrically conductive machining powder from wire cut electric discharge machining.

In addition, fluororesin has good chemical resistance, so when wire cut electrical discharge machining is performed on a workpiece made of a material that is prone to rust, such as iron, if the machining time is long, rust preventives (such as ethylene glycol) may be added to the machining fluid. (Organic substances such as Further, since the fluororesin can sufficiently withstand temperature changes, the fluororesin layer does not deteriorate and has resilience even when a wire-cut electrical discharge machine is stored, for example, in a cold region.

(Embodiment) FIG. 1 is a cross-sectional view of a part of the machining tank 2 in an embodiment of the wire-cut electrical discharge machine of the present invention, and the same components as the conventional example shown in FIGS. 2 and 3 are shown. are given the same reference numerals. Further, it is assumed that the components not shown in FIG. 1 are the same as those of the conventional wire-cut electric discharge machine.

In this embodiment, the arm 5 (as shown in FIGS. 2 and 3) is attached near the lower end of the side wall of the machining tank 2, in which the workpiece can be immersed in the machining liquid 4, as in the conventional example. A long hole 21 is formed to extend substantially horizontally, and a spacer 52,
53 are interposed in the horizontal direction along the edge of the elongated hole 21, and elongated holding plates 50 and 51, which are slightly longer than the length of the upper and lower edges of the elongated hole 21, each have screw holes provided at a plurality of locations. It is attached to the upper and lower edges of the elongated hole 21 by inserting and screwing screws 58 and 59 into the holes.

Between the elongated hole 21 and the holding plates 50, 51, a guide groove 27 having the same width as the spacers 52, 53 is formed in the horizontal direction along the upper and lower edges of the elongated hole 21.

The upper and lower edges of a shield 32 similar to that in the conventional example are slidably inserted into the guide groove 27, and the shield 32 is shown in FIGS. 2 and 3 as in the conventional example. It is adapted to be wound up or rewound by a winding roller 29 shown.

Further, on both inner surfaces of the guide groove 27 where the upper and lower edges of the shield 32 face each other, a fluororesin layer 54 such as Teflon resin manufactured by DuPont is formed on the entire both inner surfaces of the guide groove 27. ing.

With such a configuration, in this embodiment, the arm 5
When the shield body 32 moves in the X direction in FIG. Therefore, the sliding resistance is small, and processing powder generated in the processing tank 2 does not adhere to the fluororesin layer 54, so that good sliding action can always be obtained.

(Effects of the invention) As explained in detail above, according to the wire-cut electric discharge machine of the invention, the entire sliding area of the upper and lower sides of the strip-shaped shield and both inner surfaces of the guide groove facing each other is wettable. Due to the formation of a fluororesin layer with poor quality, metal fine powder such as wire electrode material and processing waste from the workpiece floating in the machining tank due to electrical discharge machining is
There is no adhesion to any part of the sliding surface between the guide groove and the shield, the sliding surface between the guide groove and the shield is always kept clean, and an increase in slip resistance can be prevented. Therefore, it is also possible to prevent deterioration of sealing performance. Furthermore, since fluororesin has excellent electrical insulation properties, it is possible to prevent electrolytic corrosion caused by electrically conductive machining powder from wire cut electrical discharge machining.

Furthermore, since fluororesin has good chemical resistance, there is no alteration or deterioration due to rust preventive agents in the processing fluid.

Furthermore, since fluororesin can sufficiently withstand temperature changes, wire-cut electrical discharge machines can be stored in cold regions.

Therefore, by using the fluororesin layer as the solid lubricant layer as described above, the performance and durability of the wire-cut electrical discharge machine can be sufficiently improved.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of the long hole portion of the processing tank in an embodiment of the present invention, Fig. 2 is an exploded perspective view showing the seal structure of the long hole in the processing tank in a conventional example, and Fig. 3 is the same seal structure. FIG. 2... Processing tank, 21... Long hole, 27... Guide groove, 32... Shielding body, 50, 51... Holding plate, 5
2-53...Spacer, 54-57...Fluororesin layer.

Claims (1)

[Scope of Claim for Utility Model Registration] A machining tank that houses a workpiece inside and immerses the workpiece in a machining liquid; a long hole formed to extend along the side wall of the machining tank; A guide groove provided above and below the long hole, a band-shaped shield that is slidably supported by the guide groove and covers the long hole, and the shield slides along the guide groove. A wire-cut electric discharge machine equipped with a sliding means, characterized in that a fluororesin layer is formed over the entire sliding area of both inner surfaces of the guide groove facing the upper and lower sides of the strip-shaped shield. Wire cut electric discharge machine.