CN100488688C - Non-conducting material spark milling electrode tip - Google Patents

Abstract

The invention relates to an electric spark milling electrode head of a non-conductive material, which belongs to the field of mechanical processing. It includes a brush head (1), a positive tool electrode (2), an insulating spacer (3), a negative tool electrode (4), a collet (5), an electromagnetic oscillator (6), a spindle system (7), Spindle head (8), liquid injection tube (9), insulating jacket (10), collet lock nut (11), negative tool electrode brush (12), positive tool electrode brush (13) and water base Conductive fluid (14). During processing, the water-based conductive liquid (14) is brushed on the surface of the non-conductive material workpiece by the brushing head (1). When the electromagnetic oscillator (6) drives the positive and negative tool electrodes to lift upward, the conductive liquid is absorbed along the The surface of the conductive workpiece flows to the lower ends of the two electrodes, causing the ends of the two poles to generate spark discharge on the surface of the non-conductive workpiece for EDM milling. The invention has the advantages of simple structure, high efficiency and low cost.

Description

EDM electrode tip for non-conductive material

technical field

The invention belongs to the field of mechanical processing and relates to an electric spark milling electrode head of a non-conductive material.

Background technique

At present, the electrical machining methods of non-conductive materials studied by scholars at home and abroad mainly include: high-voltage EDM, auxiliary electrode machining, electrolytic EDM composite machining, etc.

High-voltage EDM is to put an insulating workpiece between the pointed electrode and the flat electrode, and apply a DC or power frequency AC high voltage between the two electrodes, so that the air near the pointed electrode is broken down, and glow discharge erosion occurs. Due to the parasitic capacitance between the two poles, the power supply becomes high-frequency or pulsed, and a large glow current can flow. The voltage of the high-voltage and high-frequency power supply it uses is 5000-6000 volts, the highest voltage is 12000 volts, and the frequency is tens of kilohertz to tens of megahertz. This kind of processing method can only be used for the processing of shallow holes, and the surface of the processed holes is relatively rough.

The auxiliary electrode EDM method pre-places a metal sheet or metal mesh on the surface of the non-conductive material as an auxiliary electrode. When the tool electrode discharges through the auxiliary electrode, a layer of carbonized conductive layer is formed on the surface of the non-conductive material. The surface of the workpiece is conductive, and a discharge is generated between the tool electrode and the newly formed conductive layer. When the old conductive layer is etched away, a new conductive layer is formed, thereby realizing the EDM of non-conductive materials; The method of forming a conductive layer by plating metal on the surface of a non-conductive material, coating a conductive paint, etc., realizes the electric discharge machining of a non-conductive material, but its processing efficiency and accuracy are low.

The research and development of EDM technology for non-conductive materials is a research hotspot in the field of EDM technology today. At present, scholars at home and abroad are mostly focusing on the research of electrolytic EDM composite processing technology for non-conductive materials. This processing technology uses the spark discharge in the electrolyte for processing. During processing, the tool electrode is connected to the negative pole of the pulse power supply, and the auxiliary electrode is connected to the pulse. The positive pole of the power supply, when a pulse voltage is applied between the two poles, bubbles are generated on the surface of the tool electrode by electrochemical action, and a high potential gradient is formed between the surface of the tool electrode and the electrolyte through the bubbles, causing spark discharge, which is generated during discharge. The instantaneous high temperature and shock waves can achieve the purpose of eroding non-conductive materials. This kind of processing method has problems such as low efficiency, high energy consumption, low processing precision, poor surface quality, harmful electrolytic gas is discharged during processing, and the processing environment is poor. Aiming at the problems of low efficiency and high energy consumption in the usual non-conductive material electrolytic EDM composite machining technology, Liu Yonghong proposed the non-conductive material gas-filled electrolytic EDM composite machining technology. Although the processing productivity of the required non-conductive phase has been greatly improved, it is still relatively low when used in actual production, and the processing accuracy and surface quality are poor. At the same time, harmful electrolytic gases are emitted during the processing process, and the processing environment is poor. .

Contents of the invention

The purpose of the present invention is to provide a non-conductive material electric discharge milling electrode head, develop new non-conductive material electric discharge machining equipment, improve the processing efficiency of non-conductive difficult-to-machine materials, and reduce its processing cost.

Principle of the present invention: the invented electrode head for EDM of non-conductive material is mainly composed of brushing head 1, positive tool electrode 2, insulating spacer 3, negative tool electrode 4, collet chuck 5, electromagnetic oscillator 6, and spindle system 7. Spindle head 8, liquid injection pipe 9, insulating jacket 10, collet lock nut 11, negative tool electrode brush 12, positive tool electrode brush 13, water-based conductive liquid 14, etc. During electric discharge milling, the positive tool electrode 2 and the negative tool electrode 4 are respectively connected to the positive and negative poles of the pulse power supply, the positive and negative tool electrodes are connected together through the insulating spacer 3, and the negative tool electrode 4 is connected to the The electromagnetic oscillator 6 is connected. Driven by the electromagnetic oscillator 6, the positive and negative tool electrodes vibrate up and down. In addition, the positive and negative tool electrodes are also driven by the spindle head 8 to rotate and move in the Z direction. The conductive liquid 14 is brushed on the surface of the non-conductive material workpiece through the inner hole of the negative tool electrode 4 and the brushing head 1. When the electromagnetic oscillator 6 drives the positive and negative tool electrodes to lift upward, the conductive liquid is absorbed along the surface of the non-conductive material. The surface of the workpiece spreads around to make the surface of the workpiece under the tool electrode conductive, and the conductive liquid between the end faces of the positive and negative tool electrodes generates spark discharge on the surface of the non-conductive material workpiece, which is caused by the instantaneous high temperature and high pressure generated during the discharge. Etching processes non-conductive materials. The non-conductive material workpiece to be processed is installed on the X and Y direction moving worktable, and is driven by the X and Y direction moving worktable to move in the X and Y directions, and the complex machining is realized by the linkage between the worktable and the spindle head EDM machining of shaped non-conductive material workpieces.

The present invention has the following advantages:

1. The instantaneous high temperature and high pressure generated by the spark discharge caused by the conductive liquid flowing through the end faces of the positive and negative tool electrodes on the surface of non-conductive materials are used to etch and process non-conductive materials, and various difficult-to-process non-conductive materials can be processed; The method of multi-axis linkage can realize the EDM milling of non-conductive material workpieces with complex structures and shapes.

2. By adjusting the spark discharge parameters, the rough, medium and finish machining of non-conductive materials can be realized on the same machine tool.

3. In the process of EDM milling of non-conductive materials, the macroscopic force between the positive and negative tool electrodes and the workpiece is very small, which can easily realize the processing of complex low-rigidity non-conductive material parts.

4. The conductive graphite powder is used as the medium to prepare the water-based conductive liquid, and the processing process does not produce electrolysis, which avoids the problems of poor processing environment and easy corrosion of machine tools in the electrolysis-edm composite processing method.

5. Simple structure and reliable operation.

Description of drawings

The accompanying drawing is a schematic structural view of the electric spark milling electrode tip designed according to the present invention.

Detailed ways

See attached picture. The electric spark milling electrode head for non-conductive material of the present invention comprises a brushing head 1, a positive tool electrode 2, an insulating spacer 3, a negative tool electrode 4, a collet 5, an electromagnetic oscillator 6, a spindle system 7, a spindle head 8, Liquid injection pipe 9, insulating jacket 10, collet lock nut 11, negative tool electrode brush 12, positive tool electrode brush 13 and water-based conductive liquid 14. The brushing head 1 brushes the conductive tuck in the inner hole of the negative tool electrode 4 on the surface of the non-conductive material workpiece to form a conductive condition on the workpiece surface; the positive tool electrode 2 is connected to the positive pole of the pulse power supply through the positive tool electrode brush 13 ; The insulating spacer 3 is used to isolate the positive and negative tool electrodes, and to consolidate them together; the negative tool electrode 4 is connected to the electromagnetic oscillator 6 through the collet 5, and is connected to the negative electrode of the pulse power supply through the negative tool electrode brush 12 The inner hole is the passage of the water-based conductive liquid, and the lower end of the inner hole is equipped with a brushing head 1; the collet 5 is used to clamp the negative tool electrode 4; the electromagnetic oscillator 6 is used to drive the positive and negative tool electrodes in the Vibrate up and down during processing. When it drives the positive and negative tool electrodes upward, the adsorbed conductive liquid diffuses along the surface of the non-conductive material workpiece to make the surface of the workpiece under the tool electrode conductive, and the gap between the end faces of the positive and negative tool electrodes The spark discharge is generated on the surface of the non-conductive material workpiece through the conductive liquid, and the non-conductive material is etched by the instantaneous high temperature and high pressure generated during the discharge. When it moves downward, the end faces of the positive and negative tool electrodes are pressed against the non-conductive material. When the material is on the surface of the workpiece, the conductive liquid on the surface of the workpiece facing the positive and negative tool electrodes is squeezed away, and the spark discharge stops; the spindle system 7 is equipped with a spindle head, which can drive the spindle head to move in the Z direction. The motor and the DC motor that can drive the main shaft to perform rotational movement, under the control of the servo control system, the main shaft head drives the positive and negative tool electrodes to perform rotational movement and move in the Z direction; Through, its lower end is inserted in the inner hole of negative tool electrode 4, is used for providing conductive liquid to the inner hole of negative tool electrode 4; Insulation jacket 10 is used for isolating collet 5 and negative tool electrode 4; Collet locks The nut 11 is installed on the collet 5, and the collet 5 can clamp or loosen the negative tool electrode 4 by rotating the collet lock nut 11; the negative tool electrode brush 12 is used to connect the negative tool electrode 4 and the pulse The negative pole of the power supply provides a current path during electric spark milling; the positive tool electrode brush 13 is used to connect the positive pole of the positive tool electrode 2 and the pulse power supply to provide a current path during electric spark milling; the water-based conductive liquid 14 is based on Graphite powder is formulated as a conductive medium and is mainly used to form a conductive layer on the surface of a non-conductive material workpiece. During processing, the conductive liquid in the center hole of the negative tool electrode is brushed on the surface of the non-conductive workpiece material through the brushing head, and when the electromagnetic oscillator drives the positive and negative tool electrodes upward, the conductive liquid moves along the non-conductive The surface spreads to the surroundings. When the conductive liquid flows through the ends of the positive and negative tool electrodes, spark discharge will be caused. The instantaneous high temperature and high pressure generated during the discharge will etch away the processed non-conductive materials. When the end is pressed on the surface of the non-conductive material workpiece, the spark discharge stops, and then the positive and negative tool electrodes are lifted up again, causing spark discharge. If this goes on reciprocatingly, the EDM of non-conductive materials can be realized. With the help of the linkage between the electric discharge milling electrode head and the worktable designed by the present invention, the electric discharge milling of the non-conductive material workpiece with complex shape can be realized.

Claims (2)

1. A non-conductive material electric discharge milling electrode tip, which includes a brushing head (1), a positive tool electrode (2), an insulating spacer (3), a negative tool electrode (4), a collet (5), Electromagnetic oscillator (6), spindle system (7), spindle head (8), liquid injection pipe (9), insulating jacket (10), collet lock nut (11), negative tool electrode brush (12 ), positive tool electrode brush (13), water-based conductive liquid (14), characterized in that: the positive tool electrode (2) is connected to the positive pole of the electric spark pulse power supply through the positive tool electrode brush (13), and the negative tool electrode (4) Connect to the negative electrode of the electric spark pulse power supply through the negative tool electrode brush (12), and the water-based conductive liquid (14) is brushed on the non On the surface of the conductive material workpiece, when the electromagnetic oscillator (6) drives the positive tool electrode (2) and the negative tool electrode (4) to lift upward, the conductive liquid is absorbed, and the conductive liquid is diffused along the surface of the non-conductive material workpiece to the surroundings, so that The non-conductive material workpiece surface under the positive tool electrode (2) and the negative tool electrode (4) conducts electricity, and the water-based conductive liquid (14) is passed between the end faces of the positive tool electrode (2) and the negative tool electrode (4) on the non-conductive material Spark discharge erosion machining is generated on the surface of the workpiece. 2. The electric spark milling electrode tip for non-conductive material as claimed in claim 1, characterized in that: the positive tool electrode (2) is installed on the negative tool electrode (4) through an insulating spacer (3), and the negative tool electrode (4) ) is connected to the electromagnetic oscillator (6) through the collet (5), under the action of the electromagnetic oscillator (6), the positive tool electrode (2) and the negative tool electrode (4) vibrate up and down. In addition, the positive tool electrode (2) and the negative tool electrode (4) are driven by the spindle head (8) to rotate and move in the Z direction.

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