Electric discharge machining hole drilling
AssigneeUnited Technologies Corporation
InventorsSergey Mironets, James M. Koonankeil, Edward F. Pietraszkiewicz, Thomas R. Davis
Life of this patent
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Abstract
An apparatus and method for machining apertures into a conductive workpiece is disclosed. The apparatus has a tank capable of holding a dielectric fluid, and a fixture for holding the workpiece in the tank. An electric discharge machine with an electrode, a power supply connected to the electrode that produces machining pulses for electric discharge machining through the workpiece, and a controller for regulating the power supply and electrode position is also part of the apparatus. Finally, the apparatus has a pressure transducer connected to the fixture, and a process controller in communication with the electric discharge machine controller and pressure transducer.
Claims17
An apparatus for machining apertures into a conductive workpiece with a cavity, the apparatus comprising:
- a tank for containing a dielectric fluid;
- a fixture for holding the workpiece in the tank;
- an electric discharge machine for forming apertures in the workpiece by electric discharge machining;
- a pressure transducer connected to the fixture for sensing pressure within the cavity of the workpiece;
- and
- a process controller in communication with an electric discharge machine controller and pressure transducer for controlling operation of the electric discharge machine as a function of the sensed pressure.
A method of machining a workpiece with a cavity utilizing electric discharge machining, the method comprising:
- securing a workpiece in a tank;
- connecting a pressure transducer to a fluid channel carrying a dielectric fluid to sense pressure within the cavity of the workpiece;
- removing material from the workpiece by electric discharge machining to create at least one aperture;
- and
- stopping the material removal based upon a signal received from the pressure transducer;
- wherein the pressure transducer senses a pressure drop, and the resultant pressure drop of a first aperture in the workpiece is compared to a nominal value and a feedback to the electric discharge machine (EDM) controller which adjusts the parameters for drilling a second aperture so that the cumulative pressure gradient for the first and second apertures is targeted to the established nominal value;
- and
- wherein the cavity in the workpiece is connected to a fluid channel in a fixture, and the fluid channel in the fixture is connected to the pressure transducer.
A method of drilling a plurality of holes in a hollow cavity component, the method comprising:
- fixturing the component within a tank containing a bed of fluid;
- positioning an electric discharge machine over the component;
- machining the plurality of holes simultaneously by utilizing the electric discharge machine containing a plurality of electrodes;
- sensing pressure from an interior cavity of the component with a pressure transducer;
- and
- stopping the machining based on the sensed pressure;
- wherein the signal is produced from a differential pressure between a cavity in the component and the pressure of the fluid in the tank.
Dependencies are inferred from the claim text.