JPH0457448B2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a wire cut electrical discharge machining method.
This is particularly useful when processing a workpiece that has a concave portion, such as a die, on its surface.

BACKGROUND TECHNOLOGY As shown in Fig. 2, when a die 1 that is a workpiece has a recess 2 (referred to as a counterbore space) that is a space created by a stepped counterbore, a machining fluid injection nozzle must be brought close to the bottom of this recess 2. Since it is difficult to form a machining fluid, it is not possible to supply enough machining fluid to the machining part, so I try to increase the fluid pressure, but it does not work as expected.

Problems to be Solved by the Invention As described above, when there is a recess on the surface of the workpiece and the tip of the machining fluid injection nozzle cannot be brought close to the machining part, the supply of machining fluid to the machining gap is insufficient. Since the machining speed can be kept low, the purpose of the present invention is to supply sufficient machining liquid to the machining gap to enable high-speed machining even when there are recesses on the surface of the workpiece. do.

Means for Solving the Problems In order to achieve the above object, the present invention, when machining a workpiece having a recessed portion on its surface, surrounds a machining injection nozzle and pressurizes the surface of the workpiece to contact the recessed portion. The method is characterized in that a lid-like covering is provided that serves as a sealed chamber, and processing is performed while spraying and supplying machining liquid from the nozzle with the recessed portion serving as a sealed chamber.

Function Therefore, in the present invention, even if the machining fluid injection nozzle itself cannot approach the machining part, the recess such as the counterbore part is used as a sealed chamber so that sufficient hydraulic pressure of the machining fluid can be applied to the machining gap. It becomes possible to supply sufficient machining fluid and perform wire cut electric discharge machining at high speed.

Embodiment Next, the present invention will be explained based on the drawings.
Figures 3 and 3 are side sectional views of main parts of processing equipment showing different embodiments, in which 1 is a workpiece such as a die and has a processing part 1', 2 is a recess such as a counterbore space, and 3 is a nozzle 8. A lid-like covering that surrounds and pressurizes the surface of the workpiece 1 to make the recess 2 a sealed chamber, 4 is a filling such as sponge, and the lid-like covering 3 is made of a synthetic resin plate, ceramic, etc. It is preferable if it has electrical insulation properties and is transparent because the processed parts can be seen. Reference numeral 5 denotes a spring for pressing the coating 3 against the workpiece 1, which also serves as a suspension member for the nozzle 8 or its holder.
It may be provided separately. The other 6 is a wire electrode, which is sent out from a feed reel (not shown), passes through a number of guide rollers, passes through an upper positioning guide 7, forms a machining gap with a workpiece 1 such as a die, and is connected to a machining power source. After applying a voltage pulse to the workpiece 1 to perform electrical discharge machining,
It is wound onto a take-up reel through a lower positioning guide 7' and a number of guide rollers, and 8,
8' is a nozzle that spouts machining fluid. Thus, machining liquid is spouted from the jet nozzles 8, 8' into the machining gap between the wire electrode 6 and the die 1, and a machining voltage pulse is applied between the wire electrode 6 and the die 1 to perform electrical discharge machining. During machining, a recess such as a counterbore space in a workpiece 1 such as a die is covered with a covering 3 and kept in a sealed state, and the wire is injected while supplying machining liquid from a nozzle 8 with the recess 2 serving as a sealed chamber. Since relative machining feed is performed between the electrode 6 and the workpiece 1, that is, the coating 3 slides while being in light pressure contact with the surface of the workpiece 1 on the side where the recess 2 is located, and the recess 2 is being machined. By keeping it in a state where it is not opened, the machining fluid always fills the recess, and a sufficient amount of fluid pressure can be applied to the machining gap between the wire electrode 6 and the workpiece 1. Therefore, sufficient machining fluid can be supplied to the machining gap. This can promote high-speed machining.

Effects of the Invention As described above, according to the present invention, when machining a workpiece such as a die, where machining liquid could not be applied to the machining gap as desired due to the presence of a space in a recess such as a counterbore,
By using the counterbore space as a sealed chamber and spouting the machining fluid into it, sufficient fluid pressure can be applied to supply a sufficient amount of machining fluid to the machining gap, and as a result, high-speed machining becomes possible.

[Brief explanation of the drawing]

1 and 3 are side sectional views of main parts of a processing apparatus showing different embodiments of the present invention, and FIG. 2 is a perspective view of a die 1. In the figure, 1 is a workpiece (dice), 2 is a recess (counterbore space), 3 is a lid-like covering, 4 is a sponge, 5 is a spring, 6 is a wire electrode, 7 and 7' are guides,
8, 8' are machining fluid injection nozzles.

Claims (1)

[Claims] 1 While spraying and supplying machining liquid from a nozzle to the machining gap formed by facing each other between the workpiece and the wire electrode, voltage pulses are applied between the two to generate intermittent electrical discharge, and the machining gap is approximately orthogonal to the wire electrode. In wire cut electrical discharge machining, which cuts out a desired contour shape by giving a relative machining feed in the plane direction, when machining a workpiece with a concave part on the surface, the nozzle is surrounded and the workpiece is Wire cut electric discharge machining characterized in that a lid-like covering is provided in pressurized contact with the surface to make the recess a sealed chamber, and machining is carried out while spraying and supplying machining fluid from the nozzle while the recess is a sealed chamber. Method.