JPH0295517A - Feeder die for wire cut electric discharge machining machine - Google Patents

Abstract

PURPOSE:To prevent lowering of processing speed and to processing accuracy by cooling a feeder die that feeds a power supply to a wire electrode with a Peltier element. CONSTITUTION:While keeping contact and passing through a die 10, a wire W receives the power supply. And, at the same time, processing liquid in jet stream flows into there in parallel with the wire W, and proceeds to a work not shown in the drawing. Then, small quantity of processing liquid proceeds to a Peltier element 20 from a transmissible hole 12, and the liquid is sent to the inside of a Peltier element 20 from a transmissible hole 24. On the other hand, the electric current flows in the fixed direction through terminals 21, 22 of the Peltier element 20, and the Peltier element is cooled. Keeping pace with this cooling, the processing liquid filled around fins 23 is further cooled and the entire die 10 is cooled.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a power feeding die for a wire-cut electrical discharge machine.

[Prior Art] In a wire-cut electrical discharge machine, the current flowing through the power supply die is generally large, so the power supply die generates heat during electrical discharge machining. As a result, the electrical resistance of the feeding die increases, the electrical resistance of the contact portion between the feeding die and the wire also increases, and the current flowing through the wire decreases. This reduces the machining speed.

To prevent this, it is sufficient to cool the power supply die part.For example, it is recommended to apply a low temperature jet (processing liquid) of about 0°C to the power supply die part.This will reduce the electrical resistance of the power supply die itself, The electrical resistance of the contact part with the wire is reduced, which increases the current applied and therefore increases the processing speed.

[Problem B to be Solved by the Invention] In the conventional cooling method described above, the low-temperature jet is applied to the workpiece, and the workpiece is processed in a low-temperature state. Even if the machining accuracy is maintained at a predetermined value when the workpiece is at a low temperature, there is a problem in that the machining accuracy decreases when the workpiece is returned to room temperature.

SUMMARY OF THE INVENTION An object of the present invention is to provide a power feeding die for a wire-cut electrical discharge machine that can prevent reduction in machining speed due to heating of the power feeding die and does not reduce machining accuracy.

[Means for Solving the Problems] In the present invention, a power supply die that supplies power to a wire electrode is cooled with a Peltier element.

[Function] In the present invention, since the power feeding die that supplies power to the wire electrode is cooled by a Peltier element, it is possible to prevent a decrease in machining speed due to heating of the power feeding die, and the machining accuracy does not decrease.

[Example] FIG. 1 is a perspective view showing an embodiment of the present invention.

In this embodiment, a power feeding die 10 has a recess 11, and a Peltier element 20 is housed in the recess 11.

FIG. 2 is an exploded perspective view of the first embodiment.

The Peltier element 20 is provided with terminals 21 and 22, and a plurality of fins 23 and 23 are provided in the center thereof. . . . and through holes 24 and 25 through which the machining fluid passes are provided. The fins 23 efficiently collect heat cooled by the Peltier element 20 from the surroundings. Through hole 24.2
5 guides liquid such as machining liquid through the through hole 24 and connects the fin 23
The liquid is gradually released from the through hole 25 to the outside of the die 10 via the through hole 25. The through holes 24 and 25 only need to be filled with liquid such as machining fluid around the fins 23, and their diameters may be small.

FIG. 3 is a longitudinal cross-sectional view taken along the line (■--) in the first embodiment.

As shown in FIG. 3, the conical recess 11 of the die lO
A through hole 12 is provided in the middle of the hole 12 , and liquid such as machining fluid that enters through the through hole 12 reaches the Peltier element 20 and passes through the through hole 24 to the fin 23 .

Next, the operation of the above embodiment will be explained.

The wire W receives power while contacting and passing through the die 10. At the same time, the machining fluid flows in parallel with the wire W in the direction shown by the arrow in FIG. 1 in the form of a jet toward a workpiece (not shown). The machining liquid is directed toward the Peltier element 20, and is sent into the Peltier element 20 through the through hole 24.

On the other hand, a current flows in a predetermined direction via the terminals 21 and 22 of the Peltier element 20, thereby cooling the Peltier element. Along with this cooling, the machining fluid filled around the fins 23 is cooled, and as this machining fluid is cooled, the entire die IO is cooled.

Therefore, when the power supply current flows through the wire W via the power feeding die 10, the die 10 itself and the die lO
Since the temperature at the contact point between the die 10 and the wire W does not rise that much, the resistance value of the die 10 itself and the resistance value at the contact point between the die 10 and the wire W are low, and the machining current does not decrease. faster than Note that since the temperature at the contact point between the die 10 and the wire W does not rise, there is little thermal change in the wire W itself, and the disadvantage that the wire W is easily cut can be overcome.

Further, in the above embodiment, since the machining fluid is partially cooled instead of cooling the entire machining fluid, the temperature of the workpiece decreases only slightly, and the machining accuracy does not decrease.

In the above embodiment, the machining fluid flowing toward the Peltier element 20 forms a bypass path, unlike the flow toward the workpiece along the wire W, but the machining fluid flows parallel to the wire W without performing the bypass. The liquid may be allowed to flow into the Peltier element 20 without changing its direction; in this case,
The through hole 12 is no longer required.

In addition, although the Peltier device 20 is housed in the recess of the die 10, the Peltier device 20 is placed outside the die 10.
It may be arranged so that 0 is pasted.

Furthermore, as the shape of the Peltier element 20, a shape other than the above embodiments may be adopted.

[Effects of the Invention] According to the present invention, it is possible to prevent a decrease in machining speed due to heating of the power feeding die, and there is an effect that machining accuracy does not decrease.

12...Through hole, 20... Peltier element, 24.25...Through hole.

Claims (3)

[Claims] (1) A power supply die for a wire-cut electrical discharge machine, characterized in that the power supply die that supplies power to a wire electrode is cooled by a Peltier element. (2) A power feeding die for a wire-cut electric discharge machine according to claim (1), wherein the Peltier element is inserted into or attached to the outside of the power feeding die. (3) In claim (1), the Peltier element is inserted into the power feeding die, the Peltier element cools the machining fluid flowing along the wire electrode, and the cooled machining fluid flows into the power feeding die. A power feeding die for wire cut electrical discharge machines that is characterized by cooling.