The main body of the electrical discharge machining (EDM) machine includes the bed, column, shaft, and table, primarily used for completing tooling, fixtures, debugging, etc. The frame needs to have sufficient rigidity to prevent the machine from deforming during processing, which would hinder its ability to perform discharge machining. During EDM, both the tool electrode and the workpiece are submerged in the working fluid. The main function of the EDM machine is to compress the spark channel during discharge, allowing the current to concentrate in a small area; after discharge, it promptly eliminates ionization, restores insulation, and prevents arc generation, while the working fluid cools the tool and workpiece. To timely remove the erosion products from the electrode gap, the machine is also equipped with a working fluid circulation system, utilizing forced circulation of the working fluid to complete its operation.

Bed and Column

The bed frame is the basic structure that ensures the electrode and the worktable, workpiece are properly positioned. If the machine's precision is not high, it is difficult to guarantee processing accuracy, and its precision will be directly affected. Therefore, not only should the bed and column structures be reasonable and have high rigidity to withstand the inertial forces from the spindle's weight and sudden acceleration of moving parts, but they should also minimize deformation caused by temperature changes, eliminate internal stress through aging treatment, and remain stable over the long term.

Worktable

The worktable is mainly used to support and clamp the workpiece. In fact, by rotating the cross rods, the relative position of the electrode and the workpiece can be changed. The upper part is also equipped with a working fluid tank to hold the liquid, allowing the electrode and the workpiece to be immersed in the working fluid, serving the purposes of cooling and chip removal. The worktable allows the operator to locate frequently moving parts within the tooling fixture, moving the upper and lower sliding plates using two handwheels to change their longitudinal position, reaching the required relative position between the electrode and the workpiece. EDM machines can be divided into ordinary tabletop and precision tabletop types.

Spindle Head

The spindle is the core component of the electrical discharge perforating machine, consisting of a servo feed mechanism, guiding mechanism, anti-twist mechanism, auxiliary mechanism, etc. The discharge gap between the workpiece and the tool electrode can be controlled. The quality of the core rod directly affects its processing technical indicators, such as productivity, geometric accuracy, surface roughness, etc. In addition to structural differences, the spindle head should also meet the following conditions: (1) have certain axial and lateral rigidity and precision; (2) have sufficient feed and return speed; (3) the spindle motion should have good linearity and anti-twist capability; (4) high sensitivity without creeping; (5) different machines should have reasonable load-bearing electrode quality.