CN108284258B - One kind being totally submerged formula wire electrochemical micro-machining fixture and radial fliud flushing method - Google Patents

Abstract

The invention discloses a jig and a radial flushing method for fully submerged micro-electrolytic wire cutting. The wire electrode is fixed on the jig and placed above the electrolytic tank; one end of the flushing hole is connected to an adjustable micro-volume peristaltic pump. , the other end is connected to the inner cavity, and the adjustable micro peristaltic pump pumps the electrolyte in the electrolytic cell into the fixture and enters the inner cavity through the flushing hole, and the inner cavity runs through the entire fixture body; when processing the workpiece, the wire electrode is facing the workpiece and Feed the workpiece in translation. When the workpiece contacts the wire electrode and starts electrolytic machining, the processing products that appear during the processing are removed through the relative movement between the wire electrode and the workpiece and the flushing of the adjustable micro-peristaltic pump. The invention ensures the removal of the flocs and air bubbles produced by the wire electrode during the processing of the workpiece through the special fixture and the flushing method, greatly improves the processing stability, and is convenient to operate and easy to realize.

Description

A fully submerged micro-electrolytic wire cutting fixture and radial flushing method

technical field

The invention relates to a fully submerged micro-electrolytic wire cutting processing fixture and a radial flushing method, belonging to the technical field of micro-electrochemical processing.

Background technique

With the continuous progress of modern science and technology, the miniaturization and precision of products has become one of the main development trends. More and more microdevices and microstructures are being used in industrial fields such as medical treatment, electronics, new energy, and national defense. The continuous emergence of new micro-devices and micro-structures has driven the demand for the manufacture of metal micro-structures. The corresponding micro-processing technology has become one of the fastest-growing and most dynamic science and technology, and is highly valued by countries all over the world.

Micro electrochemical machining technology, the material transfer of micro electrochemical machining technology is carried out at the ion scale, and the size of metal ions is about 0.1nm or even smaller, and electrochemical machining also has the advantages of no loss of tools and no stress on the processed surface of the workpiece. , good processing surface quality, and has nothing to do with the hardness of the part material, etc., so this processing technology has great development potential in the field of micro-manufacturing. Micro-electrolytic wire-cutting technology is one of many micro-electrochemical processing technologies. It is a new method of electrolytic processing that uses metal wire as the tool cathode to cut and process workpieces. The metal wire is used as the tool wire electrode, the wire electrode is connected to the negative pole of the power supply, and the workpiece is connected to the positive pole of the power supply. Under the control of the high-precision motion system, the wire electrode and the workpiece carry out continuous relative motion according to the processing trajectory. An electrochemical reaction occurs between the workpiece and the wire electrode, and the workpiece material is eroded, and finally the required workpiece is processed according to the predetermined trajectory.

As we all know, in micromachining, the size of the machining gap determines the quality of machining. But when the processing gap is too small, there are two key problems. First of all, although processing requires a large amount of electrolyte, in some cases, processing completely immersed in the electrolyte will have a certain impact on the electric double layer on the surface of the workpiece.

Secondly, the processed products (floccules and air bubbles) produced during the processing cannot be discharged in time, and the fresh electrolyte cannot enter the processing gap in time. The flocs will prevent the reaction from proceeding, and the air bubbles will cause the wire electrode to bend. even damaged. Therefore, while ensuring a small machining gap, how to protect the wire electrode from the influence of liquid flow and at the same time promote the discharge of electrolytic products in the machining gap has become a key issue restricting the improvement of the practical application level of electrolytic wire cutting processing technology.

Contents of the invention

In order to prevent the bending of the wire electrode and promote the discharge of electrolytic products in the processing gap while ensuring a small processing gap, the present invention provides a fully submerged micro-electrolytic wire cutting processing fixture and a radial flushing method. The fixture and the flushing method ensure the removal of flocs and air bubbles generated during the processing of the workpiece by the wire electrode, greatly improving the stability of the processing, and are convenient to operate and easy to implement.

To achieve the above object, the present invention provides the following technical solutions:

A fixture for micro-electrolytic wire cutting, the fixture includes a fixture body, the fixture body is in the shape of a cuboid, a flushing hole is provided on one surface of the fixture body, and the flushing hole vertically runs through the entire The fixture body is connected to the opposite side, and an inner cavity is opened inward at the outlet position of the flushing hole. The inner cavity runs through the entire fixture body, and one end of the flushing hole communicates with the inner cavity; The screw is used to lock the wire electrode. The wire electrode is connected in a "U" shape by two screws, and one side passes through the surface where the inner cavity is located and passes above the inner cavity.

The surface where the two screws are located is cut into an arc surface adjacent to the surface where the inner cavity is located.

The inner cavity is a cuboid groove.

A radial flushing method for fully submerged micro-electrolytic wire cutting, comprising the following steps:

(1) Fix the wire electrode on the above-mentioned fixture and immerse it in the electrolyte;

(2) One end of the flushing hole is connected to an adjustable micro-volume peristaltic pump, and the other end is connected to the inner cavity;

(3) When the workpiece is processed in the electrolyte, the wire electrode faces the workpiece and feeds it in translation. When the workpiece contacts the wire electrode and starts electrolytic processing, the relative movement between the wire electrode and the workpiece and the adjustable The flushing of the micro peristaltic pump removes the processing products that appear during the processing.

The method of relative motion between the wire electrode and the workpiece in the above steps is as follows:

The industrial computer controls the fixture through the motion control card to drive the wire electrode to perform slight axial reciprocating motion, so that the wall surface viscosity of the wire electrode is used to drive the processed product to leave the processing gap, and then the fresh electrolyte participates in the reaction.

The flushing method of the adjustable micro peristaltic pump in the above steps is as follows:

When the air bubbles in the processed product are taken away from the processing gap, a large number of them will be close to the upper and lower areas of the processing gap, and the adjustable micro peristaltic pump will radially flush the wire electrode and its surrounding area to blow the processed product away from the processing gap , to ensure the smooth progress of processing.

The beneficial effect that the present invention reaches:

This method meets the requirements of micro-electrolytic wire cutting, effectively removes bubbles and flocs produced by electrolytic processing in a very small processing gap, and excellently guarantees processing quality and processing efficiency. At the same time, it also provides a feasible idea for the flushing method in micro-EDM. Therefore, the present invention has better portability and developability, and is suitable for further in-depth research and development.

Description of drawings

Fig. 1 is the structural representation of fixture;

Fig. 2 is the three-dimensional structure schematic diagram of fixture;

Fig. 3 is a schematic diagram of the machining process of the wire electrode and the workpiece;

Fig. 4 is a schematic diagram of wire electrode and workpiece feed processing;

Fig. 5 is a schematic diagram of a slight reciprocating movement of the wire electrode along its own axial direction.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings. The following examples are only used to illustrate the technical solution of the present invention more clearly, but not to limit the protection scope of the present invention.

As shown in Figures 1, 2, and 3, a fixture for micro-electrolytic wire cutting, the fixture includes a fixture body 5, the fixture body 5 is in the shape of a cuboid, and one surface of the fixture body 5 is set A flushing hole 1, the flushing hole 1 vertically runs through the entire fixture body 5 and connects to the opposite side, and an inner cavity 4 is opened inwardly at the exit position of the flushing hole 1, and the inner cavity 4 runs through the entire fixture body 5, and the flushing hole One end of 1 communicates with the inner cavity 4; two screws 2 are symmetrically arranged on both sides of the inner cavity 4 for locking the wire electrode 3, and the wire electrode 3 is connected in a "U" shape by two screws 2. , one edge passes through the face where the cavity 4 is located and passes above the cavity 4 .

The surface where the two screws 2 are located is cut into an arc surface adjacent to the surface where the inner cavity 4 is located.

The inner cavity 4 is a cuboid groove.

A radial flushing method for fully submerged micro-electrolytic wire cutting, comprising the following steps:

(1) Fix the wire electrode 3 on the above-mentioned fixture and immerse in the electrolyte;

(2) One end of the flushing hole 1 is connected to an adjustable micro-peristaltic pump, and the other end is connected to the inner chamber 4;

(3) When the workpiece 6 is processed in the electrolyte, the wire electrode 3 is facing the workpiece 6 and is fed in parallel to the workpiece 6. When the workpiece 6 contacts the wire electrode 3 and starts electrolytic machining, as shown in Fig. 4 and Fig. 5 As shown, the processing products that appear during the processing are removed through the relative movement between the wire electrode 3 and the workpiece 6 and the flushing of the adjustable micro peristaltic pump.

The method of relative motion between the wire electrode 3 and the workpiece 6 in the above step 3 is as follows:

The industrial computer controls the fixture through the motion control card to drive the wire electrode 3 to perform slight axial reciprocating motion, so that the wall surface viscosity of the wire electrode 3 is used to drive the processed product to leave the processing gap, and then the fresh electrolyte participates in the reaction.

The flushing method of the adjustable micro peristaltic pump in the above step 3 is as follows:

When the air bubbles in the processed product are taken away from the processing gap, a large number of air bubbles will be close to the upper and lower areas of the processing gap, and the adjustable micro peristaltic pump will radially flush the wire electrode 3 and its surrounding area to blow the processed product away from the processing Clearance to ensure the smooth progress of processing.

After the electrolyte enters the inner cavity through the flushing hole, since the inner cavity is a semi-closed structure with only one side open, the wall viscosity of the inner cavity makes the electrolyte "stay" in the inner cavity and participate in the electrochemical reaction, continuously entering The electrolyte in the inner cavity can promote the renewal of the electrolyte in the inner cavity.

Example:

In this embodiment, two relative movements between the wire electrode and the workpiece are involved. The first is the feed motion between the wire electrode and the workpiece; referring to attached drawing 4, as shown in the figure, the wire electrode and the workpiece perform continuous relative motion according to the processing trajectory under the control of the high-precision motion system, and the workpiece and the wire electrode An electrochemical reaction occurs between them, the workpiece material is etched away, and finally the required workpiece is processed according to the predetermined trajectory.

However, in the process of processing, a large number of processed products, namely air bubbles and flocs, will be produced in the processing gap. The existence of air bubbles and flocs can easily lead to the bending of the wire electrode, which greatly affects the processing, so the process of wire feeding is essential, as shown in Figure 5. The wire electrode performs slight reciprocating motion along its own axis (the arrow on the left refers to the feed of the wire electrode, and the arrow on the right refers to the slight reciprocating motion of the wire electrode), and the viscosity of the wall surface of the wire electrode drives the electrolyte in the processing gap along the line. The axial "flow" of the electrode brings air bubbles and flocs out of the processing gap, alleviating the interference of these processing products on the processing process.

But even if air bubbles and flocs are taken out of the processing gap, they will accumulate in large quantities above and below the processing gap. In this case, other processed products cannot be further discharged, and fresh electrolyte cannot quickly enter the processing gap, which greatly hinders the processing accuracy and efficiency, so the next process is the flushing process.

Figure 3 shows the workpiece being electrolytically machined. The schematic diagram of flushing is shown in Figure 3. When the air bubbles are taken away from the processing gap, a large number of them will be close to the upper and lower areas of the processing gap. At this time, the tungsten wire as the wire electrode and its surrounding areas will be flushed radially by an adjustable micro-peristaltic pump, and the processed product " Blow away" processing gap to ensure the smooth progress of processing. Since the inner cavity exists in the form of a through groove in the fixture, the adjustable micro peristaltic pump is allowed to flush at a relatively large flow rate, which can significantly improve the processing efficiency. The specific flow rate of the adjustable micro-volume peristaltic pump can be adjusted freely within tens of milliliters per minute.

When air bubbles exist in the processing gap, it will easily cause the wire electrode to bend, and the processing quality will be greatly affected. During the flushing process, on the one hand, the flushed liquid can well remove the air bubbles and flocs in the processing gap, and at the same time update the electrolyte in the processing gap; but on the other hand, the flushed liquid gives radial The force may also cause the bending of the wire electrode and affect the processing quality of the slit. Specific measures to solve this problem include the use of adjustable micro-volume peristaltic pumps and the implementation of pre-tensioning measures. The use of an adjustable micro-volume peristaltic pump can freely change the flow rate within tens of milliliters per minute, which minimizes the risk of wire electrode bending due to excessive flow rate. At the same time, as shown in Figure 1, the tightness of the wire electrode is controlled by the screw. Before processing, a certain degree of pre-tensioning measures are taken through the screw to enhance the rigidity of the wire electrode, which can effectively prevent some wire electrodes from bending due to insufficient rigidity. Circumstances that result in compromised processing quality.

The above is only a preferred embodiment of the present invention, it should be pointed out that for those of ordinary skill in the art, without departing from the technical principle of the present invention, some improvements and modifications can also be made. It should also be regarded as the protection scope of the present invention.

Claims (6)

1. a kind of fixture for wire electrochemical micro-machining, it is characterised in that: the fixture includes chuck body (5), institute Stating chuck body (5) is a rectangular-shape, and a flushing hole (1), the punching is arranged on a face of the chuck body (5) Fluid apertures (1) extends vertically through entire chuck body (5) and is connected to opposite, inwardly opens up in one in flushing hole (1) outlet port Entire chuck body (5) are run through in chamber (4), inner cavity (4), and one end of flushing hole (1) is communicated with inner cavity (4)；The face of the inner cavity (4) Two sides be symmetrical arranged two screws (2), for locking line electrode (3), line electrode (3) at "U" shaped pass through two screws (2) connection is tensed, a line passes through through the face where inner cavity (4) and above inner cavity (4).

2. a kind of fixture for wire electrochemical micro-machining according to claim 1, it is characterised in that: two screws (2) the face adjacent where face and inner cavity (4) where is cut into cambered surface.

3. a kind of fixture for wire electrochemical micro-machining according to claim 1, it is characterised in that: the inner cavity It (4) is rectangular-shape groove.

4. a kind of radial fliud flushing method for being totally submerged formula wire electrochemical micro-machining, it is characterised in that include the following steps:

(1), by line electrode (3) fixed fixture described in claim 1, submergence is in the electrolytic solution；

(2), one end of flushing hole (1) connects adjustable micro peristaltic pump, and the other end connects inner cavity (4)；

(3), in the electrolytic solution workpieces processing (6) when, line electrode (3) face workpiece (6) simultaneously to workpiece (6) be translatable feed, work as work When part (6) contacts with line electrode (3) and starts Electrolyzed Processing, by relative motion between line electrode (3) and workpiece (6) and The fliud flushing of adjustable micro peristaltic pump removes the processing product occurred in process.

5. a kind of radial fliud flushing method for being totally submerged formula wire electrochemical micro-machining according to claim 4, special Sign is: the method for the relative motion between step (3) central electrode (3) and workpiece (6) is as follows:

Industrial personal computer carries out axially reciprocating a little by motion control card control clamp strap moving-wire electrode (3), to utilize line The wall surface viscosity of electrode (3) drives processing product to leave processing gap, and then participates in fresh electrolyte in reaction.

6. a kind of radial fliud flushing method for being totally submerged formula wire electrochemical micro-machining according to claim 4, special Sign is: the method for the fliud flushing of adjustable micro peristaltic pump is as follows in the step (3):

After the bubble processed in product is brought away from processing gap, the lower regions in processing gap can be largely close in, by can It adjusts micro peristaltic pump to carry out radial fliud flushing to line electrode (3) and its near zone, processing product is blown off and processes gap, guarantee to add Work is gone on smoothly.