EDM Pressure Chamber With Inverse Flushing for Parallel Holes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Classic spark erosion drilling experiences process instabilities due to secondary discharges, conicity in holes, and prolonged process times, with electrode wear varying during the erosion process.
Innovation Solution
A pressure chamber for spark erosion machines that employs inverse pressure flushing, where the dielectric is supplied through the pressure chamber and removed through the electrode, maintaining higher pressure and minimizing dielectric space, thereby preventing secondary discharges and ensuring a parallel hole profile with reduced erosion time and consistent electrode wear.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If dielectric is supplied through electrode cavity in conventional EDM drilling, then electrode can be cooled and dielectric can reach workpiece, but particles are transported through gap between electrode and hole sidewall causing secondary discharges and process instabilities
Solution Approach 1:
The patent inverts the conventional dielectric supply path. Instead of supplying dielectric through the electrode cavity and having it exit through the gap between electrode and hole sidewall, the dielectric is supplied through a pressure chamber that directs it to flush particles through the electrode cavity. This reversal eliminates the harmful secondary discharges in the gap while maintaining effective particle removal and electrode cooling.
2Productivity
If conventional EDM drilling is used, then holes can be produced, but holes exhibit conical shape with widening from bottom to opening requiring relatively long process time
Solution Approach 1:
The patent employs hydraulic pressure flushing through a pressure chamber to control dielectric flow and particle removal. By applying pressure through the pressure chamber and directing dielectric flow through the electrode cavity, the system achieves uniform particle evacuation that maintains parallel hole walls and eliminates conical shaping, significantly improving both productivity and manufacturing precision.
3Reliability
If conventional EDM drilling is used, then electrode can remove particles through gap, but electrode wear varies during erosion process
Solution Approach 1:
The patent extracts the particle removal function from the gap between electrode and hole sidewall and relocates it to the electrode cavity. By taking out the harmful secondary discharge pathway and replacing it with controlled dielectric flow through the pressure chamber and electrode cavity, the system achieves uniform electrode wear while maintaining high productivity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution significantly reduces process time, prevents secondary discharges, and maintains a consistent electrode wear, resulting in precise, parallel holes with improved process stability.
Implementation Method 1
The pulse generator generates voltage pulses with an amplitude sufficiently high to trigger a spark discharge in the dielectric between the electrode and the workpiece to be treated. This spark discharge removes particles from the surface of the workpiece
Implementation Method 2
a seal which can be applied in a fluid-tight manner to a contact surface of the workpiece to be treated which is oriented transversely to the longitudinal axis of the pressure chamber
Implementation Method 3
the dielectric can be supplied in the dielectric space at an operating pressure that is higher than the ambient pressure. For example, the pressure under which the dielectric is supplied to the dielectric space may be at least 4 bar, in particular at least 6 bar, particularly preferably at least 8 bar
Data Source
Figure 1
Figure 2
Figure 3
AI summary
To improve the electrical discharge machining (EDM) treatment of a workpiece in such a way that the disadvantages of classical EDM drilling are completely or partially avoided or at least reduced, a pressure chamber for an EDM machine is proposed for performing EDM treatment on a workpiece, wherein the pressure chamber comprises the following: - a wall which defines an interior space of the pressure chamber; - at least one electrode guide for guiding an electrode parallel to a longitudinal axis of the pressure chamber; - a dielectric connection for supplying a dielectric to the interior space of the pressure chamber; and - a seal which can be fluid-tightly applied to a contact surface of the workpiece to be treated oriented transversely to the longitudinal axis of the pressure chamber.