CN118123147A

CN118123147A - Directional inner-flushing wheel type electrode and efficient horizontal milling type electric machining method

Info

Publication number: CN118123147A
Application number: CN202410497851.5A
Authority: CN
Inventors: 顾琳
Original assignee: Shanghai Qizhi Technology Co ltd
Current assignee: Shanghai Qizhi Technology Co ltd
Priority date: 2024-04-24
Filing date: 2024-04-24
Publication date: 2024-06-04

Abstract

The invention discloses a directional inner-flushing wheel type electrode and a high-efficiency horizontal milling type electric machining method, and belongs to the technical field of electric machining. The device comprises a wheel-shaped electrode, wherein a flushing guide mechanism is arranged in the wheel-shaped electrode, sealing structures and bearing structures are arranged on two sides of the flushing guide mechanism, the sealing structures and the bearing structures are sleeved on a flushing guide pipe, a working fluid inlet is formed in one side of the flushing guide pipe, a plug is filled in the other side of the flushing guide pipe, and a mounting surface and an outer rotor driving mechanism are sequentially sleeved on one side close to the working fluid inlet. The method comprises two modes of electric discharge machining and electrochemical machining. The invention is suitable for two modes of electric discharge machining and electrochemical machining, the wheel-shaped electrode of the electrode structure is replaceable, in the machining process, the direction of the flushing liquid of the inner flushing liquid pipe is controllable, the flushing liquid is ensured to be directed to a machining area, the influence of the too low working fluid pressure on the machining effect is avoided, the effective area is large in machining, and higher machining efficiency can be obtained.

Description

Directional inner-flushing wheel type electrode and efficient horizontal milling type electric machining method

Technical Field

The invention relates to the technical field of electric arc machining, in particular to a directional inner-flushing wheel type electrode and a high-efficiency horizontal milling type electric machining method.

Background

Arcing is the phenomenon whereby two electrodes are maintained under a voltage by gaseous charged particles, such as electrons or ions. Arc discharge (ARCDISCHARGE) is the strongest self-sustaining discharge of the discharges. When the power supply supplies electric energy with high power, the inter-electrode voltage is not required to be too high (about tens of volts), and strong current (several to tens of amperes) can continuously pass through the gas or the metal vapor between the two electrodes, and strong light is emitted, so that high temperature (thousands to tens of thousands of degrees) is generated, which is arc discharge. Arcing is a common thermal plasma (see plasma applications).

The prior art still has the following defects: 1) The blade profile processing is problematic. The blade processing is always a core process in the manufacture of aeroengines, the blade of a new generation of aeronautics with large thrust, long voyage and higher fuel economy is larger in size, the processing methods such as milling, grinding and the like are adopted to easily cause cutting deformation, the accuracy is difficult to control, and the new generation gradually adopts difficult-to-cut materials such as titanium aluminum alloy and the like, so that the traditional processing is more challenged. 2) The existing blade processing mainly comprises milling and has the methods of abrasive belt grinding and the like. However, even with expensive blade machining machines, it is difficult to control the amount of blade deformation during cutting. And the abrasive belt grinding efficiency is low, and the processing error is larger due to the large contact surface. 3) Electrochemical machining is another method that finds application in blade profile machining. The method is also non-contact processing, and has higher efficiency and low surface roughness when large current is adopted. However, the design of the formed electrode and the control of the technological parameters of electrochemical machining are complex, and the requirements on the technological personnel are high. And the energy density is not high and the efficiency is reduced in large-area processing. 4) The advantages and problems of arc machining. The arc discharge machining is a novel machining method for rapidly removing materials by utilizing the high temperature (tens of thousands degrees) of a plasma arc column generated between an electrode and a workpiece, has high energy density, is far higher than the traditional cutting machining in material removal rate of materials difficult to machine, does not contact the workpiece in the machining process, does not generate cutting stress, and has a very good application prospect. However, when a rod-like or cylindrical porous electrode is adopted for milling, the highest efficiency is affected by the size of the electrode, the linear speed from the edge to the central area in the rotation process of the electrode is inconsistent, even if the electrode is matched with high-speed inner flushing liquid, the internal flow field is difficult to uniformly control, the electrode loss is uneven, difficulty is brought to compensation, the machined surface is rough, the shape and position errors are large, and a large machining allowance is needed to be reserved for subsequent finish machining. 5) Patent CN108655519a discloses an arc discharge machining flushing area regulating and controlling system, which comprises a flushing area controllable electrode device, a machine tool handle flushing interface, a spindle base, a control unit, an interface of a machine tool numerical control system and the control unit, and a working fluid supply unit. In the processing process, the direction of the adjusting ring is controlled through the switch of the electromagnet, and the inner flushing liquid is flushed to the processing area through the notch position of the adjusting ring, so that the position of the flushing liquid area is consistent with the processing feeding direction, and the fluid power arc breaking is ensured. The invention adopts an external device to limit the direction of the flushing liquid, and has the defects that the magnetic force control regulating ring is unstable in steering, the small attractive force of the electromagnet on the magnetic material is difficult to finish the aim of sensitive regulation, the friction force is increased when the high-speed high-pressure inner flushing liquid impacts the end surface of the regulating ring, and the magnetic force attraction effect is weakened. In addition, the method is used for end face discharge end milling, and the rotation center of the electrode is required to be approximately perpendicular to the machining surface during normal machining.

Disclosure of Invention

The invention aims to provide a directional inner-flushing wheel type electrode and a high-efficiency horizontal milling type electric machining method, which solve the problems of blade profile machining, abrasive belt grinding efficiency low and large machining errors caused by large contact surfaces, and the problems of complex electrode design during large-area machining, high-current power supply requirement and inconsistent linear speeds of all parts in arc milling machining by adopting electrochemical machining.

In order to achieve the above purpose, the invention provides a directional inner liquid flushing wheel type electrode, which comprises a wheel type electrode, wherein a liquid flushing guide mechanism is arranged in the wheel type electrode, sealing structures and bearing structures are arranged on two sides of the liquid flushing guide mechanism, the sealing structures and the bearing structures are sleeved on a liquid flushing guide pipe, a working liquid inlet is formed in one side of the liquid flushing guide pipe, a plug is filled in the other side of the liquid flushing guide pipe, and a mounting surface and an outer rotor driving device are sequentially sleeved on one side of the liquid flushing guide pipe, which is close to the working liquid inlet.

Preferably, a working fluid outlet is formed at the tail end of the flushing guide mechanism, and the working fluid outlet is positioned in the wheel-shaped electrode.

Preferably, the surface of the wheel-shaped electrode is provided with a plurality of electrode flushing holes or flushing tanks which are uniformly and equidistantly arranged.

Preferably, the sealing structure comprises a first sealing cover plate, a second sealing cover plate, a first sealing ring and a second sealing ring, wherein the first sealing cover plate and the first sealing ring are positioned at one end close to the working fluid inlet, and the second sealing cover plate and the second sealing ring are positioned at one end close to the plug.

Preferably, the bearing structure comprises a first bearing and a second bearing, wherein the first bearing is positioned at one end of the working fluid inlet, the second bearing is positioned at one end close to the plug, and check rings are arranged on the outer sides of the first bearing and the second bearing.

An efficient horizontal milling type electric discharge machining method of a directional inner-flushing wheel type electrode comprises the following steps:

S1, connecting an electrode and a workpiece with a negative electrode or a positive electrode of the electrode respectively, and forming a conductive loop during processing;

S2, carrying out electric discharge machining on the workpiece, wherein during machining, working fluid is flushed out through a flushing pipe inlet, a flushing guide pipe, a flushing hole or a flushing groove of an outer ring of the electrode, and reaches a machining area;

And S3, during discharge machining, under the action of field intensity between the electrode and the workpiece, the working medium is broken down to form a plasma discharge channel, the workpiece material is etched away by utilizing high temperature of plasma, and heat and an electric corrosion product in the machining process are taken away by the interelectrode working fluid to obtain the machined workpiece.

Preferably, in step S2, an insulating or low-conductivity emulsion, water-based or oil-based working fluid is used for the discharge processing.

Preferably, in step S2, during discharge processing, the power supply outputs a dc pulse, the electrode is connected to the cathode or the anode, and correspondingly, the workpiece is connected to the anode or the cathode, the pulse width is greater than 10 μs, and the open circuit voltage is greater than 50V.

An efficient horizontal milling type electrochemical machining method of a directional inner-flushing wheel type electrode comprises the following steps:

s101, connecting an electrode with a negative electrode, connecting a workpiece with a positive electrode, and forming a conductive loop between the electrode and the workpiece;

s102, carrying out electrochemical machining on a workpiece, and adopting electrolyte solution as working solution, wherein the workpiece is subjected to anodic dissolution and is etched;

And S103, feeding the electrode along a preset track, enabling the movement direction of the outer ring of the electrode at the processing point to be tangential to the surface of the workpiece, discharging or carrying out electrolytic processing only on the outer ring, enabling the linear speeds of the points to be consistent, and finally finishing the processing of the curved surface or the plane.

Preferably, in step S102, when the electrochemical machining mode is adopted, a direct current power supply is adopted, the current is greater than 1A, and the voltage is not greater than 40V.

Therefore, the directional inner-flushing wheel type electrode and the efficient horizontal milling type electric machining method adopting the structure have the following beneficial effects:

(1) The invention is suitable for two modes of electric discharge machining and electrochemical machining, the wheel-shaped electrode of the electrode structure is replaceable, and in the machining process, the direction of the flushing liquid of the inner flushing liquid pipe is controllable, so that the flushing liquid is ensured to point to a machining area, and the influence on the machining effect caused by too low working fluid pressure is avoided.

(2) The wheel type electrode is adopted, the effective area is larger than that of the rod type electrode and the disc electrode during processing, and higher processing efficiency can be obtained.

(3) When the invention adopts the discharge mode for processing, the electrode and the workpiece are not in mechanical contact, macroscopic cutting force is avoided, and the processing of thin-wall parts such as blades is facilitated.

(4) When the invention adopts the discharge mode, the material can be etched and removed rapidly by adopting the arc processing mode with high current, and then the discharge energy is reduced to etch and remove the material in the spark discharge mode.

(5) When the invention adopts discharge processing, the plasma arc column is elongated due to the combined action of flushing liquid and rotation, so that the energy is more dispersed, shallower etching pits can be formed, and the surface with better quality is obtained.

(6) When the electrochemical machining mode is adopted, the localization of anodic dissolution can be greatly improved due to the comprehensive action of the flushing liquid and the wheel-shaped electrode, and the high-precision high-quality molded surface can be obtained.

The technical scheme of the invention is further described in detail through the drawings and the embodiments.

Drawings

FIG. 1 is a schematic diagram of an explosion structure of a directional inner-flushing wheel type electrode and a high-efficiency horizontal milling type electric machining method;

FIG. 2 is a schematic diagram of the overall structure of a directional inner-flushing wheel type electrode and a high-efficiency horizontal milling type electric machining method according to the invention;

FIG. 3 is a schematic diagram of the working modes of a directional inner-flushing wheel type electrode and a high-efficiency horizontal milling type electric machining method according to the invention;

Reference numerals

1. The device comprises a flushing guide pipe, 101, a working fluid inlet, 2, a mounting surface, 3, a flushing guide mechanism, 301, a working fluid outlet, 4, an outer rotor driving device, 5, a first bearing, 6, a first sealing ring, 7, a first sealing cover plate, 8, a wheel-shaped electrode, 9, a second sealing ring, 10, a second bearing, 11, a second sealing cover plate, 12 and a plug.

Detailed Description

The technical scheme of the invention is further described below through the attached drawings and the embodiments.

Unless defined otherwise, technical or scientific terms used herein should be given the ordinary meaning as understood by one of ordinary skill in the art to which this invention belongs. The terms "first," "second," and the like, as used herein, do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that elements or items preceding the word are included in the element or item listed after the word and equivalents thereof, but does not exclude other elements or items. The terms "connected" or "connected," and the like, are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", etc. are used merely to indicate relative positional relationships, which may also be changed when the absolute position of the object to be described is changed.

Examples

As shown in fig. 1-3, the invention provides a directional inner liquid-flushing wheel type electrode, which comprises a wheel type electrode 8, wherein a liquid-flushing guide mechanism 3 is clamped in the wheel type electrode 8, both sides of the liquid-flushing guide mechanism 3 are respectively provided with a sealing structure and a bearing structure, the liquid-flushing guide mechanism 3, the sealing structure and the bearing structure are respectively sleeved on a liquid-flushing guide pipe 1, a working liquid inlet 101 is formed in one side of the liquid-flushing guide pipe 1, a plug 12 is filled in the other side of the liquid-flushing guide pipe 1, a mounting surface 2 and an outer rotor driving device 4 are sequentially sleeved on one side, close to the working liquid inlet 101, of the outer rotor driving device 4 can drive an outer rotor to rotate by gears, pulleys and the like.

The tail end of the flushing guide mechanism 3 is provided with a working fluid outlet 301, and the working fluid outlet 301 is positioned inside the wheel-shaped electrode 8.

The surface of the wheel-shaped electrode 8 is provided with a plurality of electrode flushing holes or flushing tanks which are uniformly and equidistantly arranged.

The sealing structure comprises a first sealing cover plate 7, a second sealing cover plate 11, a first sealing ring 6 and a second sealing ring 9, wherein the first sealing cover plate 7 and the first sealing ring 6 are positioned at one end close to the working fluid inlet 101, and the second sealing cover plate 11 and the second sealing ring 9 are positioned at one end close to the plug 12.

The bearing structure comprises a first bearing 5 and a second bearing 10, wherein the first bearing 5 is positioned at one end of the working fluid inlet 101, the second bearing 10 is positioned at one end close to the plug 12, and check rings are arranged on the outer sides of the first bearing 5 and the second bearing 10.

and S3, during discharge machining, under the action of field intensity between the electrode and the workpiece, the working medium is broken down to form a plasma discharge channel, the workpiece material is etched away by utilizing high temperature of plasma, and heat and an electrolytic etching product in the machining process are taken away by the interelectrode working fluid to obtain the machined workpiece.

In step S2, an insulating or low-conductivity emulsion, water-based or oil-based working fluid is used for the discharge processing.

In step S2, during discharge processing, the power supply outputs a dc pulse, the electrode is connected to the cathode or the anode, and correspondingly, the workpiece is connected to the anode or the cathode, the pulse width is greater than 10 μs, and the open circuit voltage is greater than 50V.

In step S102, when the electrochemical machining mode is adopted, a direct current power supply is adopted, the current is greater than 1A, and the voltage is not greater than 40V.

Working principle: the electrode structure consists of a replaceable wheel-shaped outer ring electrode capable of rotating at high speed, a non-rotating flushing liquid guiding mechanism, a transmission part and the like. The replaceable outer ring electrode is a wheel-shaped structure with a certain thickness, a liquid flushing hole or a liquid flushing groove is formed in the radial circumferential surface, if the surface to be processed is a concave curved surface, the radius of the wheel-shaped structure is smaller than the minimum radius of the curved surface to be processed, the rotation generatrix of the wheel surface is in a convex arc shape, and the arc radius is also smaller than the minimum radius of the curved surface to be processed; if the surface to be processed is a plane or a convex curved surface, the wheel-shaped structure and the wheel-surface revolution generatrix have no radius limitation. The flushing guide mechanism consists of an outer ring mounting seat, a flushing guide pipe and the like, and the opening of the flushing guide pipe faces the processing surface, so that the directionality of flushing is improved, and the defect of insufficient flushing pressure in a processing area caused by uniform flushing of working fluid from a liquid hole or a flushing groove on the side surface Zhou Xiangchong of the electrode is avoided. The electrode clamping part is a flushing guide mechanism. When the electrode is assembled, a bearing sealing ring and a bearing retainer ring are sequentially arranged at the right end of a bulge (shaft shoulder) of the flushing guide mechanism. The rotary driving mechanism (outer rotor driving device) is installed on the installation surface (the installation seat is detachable) of the working fluid guiding mechanism, and the right shoulder of the right sealing cover plate is installed and fastened with the inner rotor of the driving device so as to rotate under the rotation of the motor. And then the mounting wheel-shaped electrode is tightly connected with the sealing cover plate. And then the left bearing sealing ring, the bearing and the bearing retainer ring are sequentially arranged on the left side of the flushing guide mechanism, and then the left sealing cover plate is arranged to be fastened with the wheel-shaped electrode. When the motor rotates, power is transmitted through the motor inner ring, the sealing cover plate and the wheel-shaped electrode, so that the electrode is driven to rotate. During processing, the outer ring of the electrode plate is driven by a transmission part to rotate at a high speed, the rotation transmission part in the case is an outer rotor driving device, and transmission modes such as a gear, a rack, a belt pulley and the like can be adopted to realize that a wheel type electrode rotates around the axis of the flushing liquid guide mechanism during processing, so that horizontal milling-like processing is performed. The working fluid enters from the right side flushing pipe in the figure, reaches the flushing hole or the flushing groove of the electrode through the outlet of the flushing guide mechanism, reaches the processing gap through the flushing hole or the flushing groove at the lower part of the electrode disc, and takes away the processing heat and the processing products. When the outer rotor driving device is adopted, insulation treatment is carried out between the sealing cover plate and the inner rotor of the motor. The power-on mode is a spring piece, a slip ring or a plug center hole center.

During machining, the electrode and the workpiece are respectively connected with the cathode or the anode of the electrode, and a conductive loop is formed with a power supply. The electrode is suitable for electric discharge machining and electrochemical machining. When the discharge processing is performed, an insulating or low-conductivity emulsion liquid and a water-based or oil-based working liquid are adopted, and when the electrochemical processing is performed, an electrolyte solution is adopted. And (3) performing electric discharge machining on the workpiece, wherein during machining, working fluid is flushed out through a flushing pipe inlet, a flushing guide pipe, a flushing hole or a flushing groove of the outer ring of the electrode, and reaches a machining area. When the discharge processing is adopted, the power supply outputs direct current pulse, the electrode is connected with the cathode or the anode, correspondingly, the workpiece is connected with the anode or the cathode, the pulse width is more than 10 mu s, and the open circuit voltage is more than 50V. Under the action of field intensity between the electrode and the workpiece, the working medium is broken down to form a plasma discharge channel, and the workpiece material is etched away by utilizing the high temperature of plasma. Heat and an electrolytic etching product in the processing process are taken away by the interelectrode working fluid. The electrode rotates during processing, so that the uniformity of processing and loss is ensured. When the electrochemical machining mode is adopted, a direct current power supply is adopted, the current is more than 1A, and the voltage is lower than 40V. An electrolyte is used as the working fluid, thereby forming a conductive loop between the electrode and the workpiece. The electrode is connected with the negative electrode, and the workpiece is connected with the positive electrode. During processing, the workpiece is dissolved by the anode and is etched away. The electrode is fed along a preset track, the machining mode is similar to horizontal milling machining, the movement direction of an electrode outer ring at a discharge point is tangential to the surface of a workpiece, the electrode is only discharged or subjected to electrolytic machining at the outer ring, the linear speed of each point is consistent, and finally the machining of a curved surface or a plane is finished. In the machining, the flow field of the machining gap is uniform, so that the machining uniformity is better than that of the electric machining by adopting a rod-shaped electrode and a formed electrode. The direction of the electrode flushing pipe can be regulated and controlled through the controlled steering of the electrode clamping head so as to ensure the electrode flushing pipe to point to a processing area. During discharge processing, the plasma arc column is elongated due to the combined action of the flushing liquid and the rotation, so that energy is more dispersed, shallower etching pits can be formed, and a surface with better quality is obtained. During electrochemical processing, the localization of anodic dissolution can be greatly improved due to the combined action of the flushing liquid and the wheel-shaped electrode.

Therefore, the directional inner-flushing wheel type electrode and the efficient horizontal milling type electric machining method are suitable for two modes of electric discharge machining and electrochemical machining, the wheel type electrode with the electrode structure is replaceable, and in the machining process, the flushing direction of the inner flushing pipe is controllable, so that flushing is ensured to point to a machining area, and the influence on the machining effect due to too low working fluid pressure is avoided. And the effective area is larger than that of the rod-shaped electrode and the disc electrode during processing, so that higher processing efficiency can be obtained.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention and not for limiting it, and although the present invention has been described in detail with reference to the preferred embodiments, it will be understood by those skilled in the art that: the technical scheme of the invention can be modified or replaced by the same, and the modified technical scheme cannot deviate from the spirit and scope of the technical scheme of the invention.

Claims

1. The utility model provides a directional interior dashing liquid wheel electrode, its characterized in that, includes the wheel electrode, the inside card of wheel electrode is equipped with dashing liquid guiding mechanism, dashing liquid guiding mechanism both sides all are provided with seal structure and bearing structure, dashing liquid guiding mechanism seal structure with bearing structure all overlaps to establish on dashing liquid pipe, the working solution entry has been seted up to one side of dashing liquid pipe, the opposite side of dashing liquid pipe is filled with the end cap, and is close to one side of working solution entry overlaps in proper order and is equipped with installation face and external rotor drive arrangement.

2. A directional inner rinse wheel electrode as set forth in claim 1 wherein: the tail end of the flushing guide mechanism is provided with a working fluid outlet which is positioned in the wheel-shaped electrode.

3. A directional inner rinse wheel electrode as set forth in claim 2 wherein: the wheel-shaped electrode surface is provided with a plurality of electrode flushing holes or flushing tanks which are uniformly and equidistantly arranged.

4. A directional inner rinse wheel electrode as set forth in claim 3 wherein: the sealing structure comprises a first sealing cover plate, a second sealing cover plate, a first sealing ring and a second sealing ring, wherein the first sealing cover plate and the first sealing ring are positioned at one end close to the working fluid inlet, and the second sealing cover plate and the second sealing ring are positioned at one end close to the plug.

5. A directional inner rinse wheel electrode as set forth in claim 4 wherein: the bearing structure comprises a first bearing and a second bearing, wherein the first bearing is positioned at one end of the working fluid inlet, the second bearing is positioned at one end close to the plug, and check rings are arranged on the outer sides of the first bearing and the second bearing.

6. A high-efficiency horizontal milling type electric discharge machining method of a directional inner-flushing wheel type electrode is characterized by comprising the following steps of: the method comprises the following steps:

s1, connecting an electrode and a workpiece with a negative electrode or a positive electrode of a power supply respectively, and forming a conductive loop during processing;

7. The efficient horizontal milling type electric discharge machining method of the directional inner-flushing wheel type electrode, which is characterized by comprising the following steps of: in step S2, an insulating or low-conductivity emulsion, water-based or oil-based working fluid is used for the discharge processing.

8. The directional inner-flushing wheel type electrode and the efficient horizontal milling type electric machining method as claimed in claim 6, wherein the directional inner-flushing wheel type electrode and the efficient horizontal milling type electric machining method are characterized in that: in step S2, during discharge processing, the power supply outputs a dc pulse, the electrode is connected to the cathode or the anode, and correspondingly, the workpiece is connected to the anode or the cathode, the pulse width is greater than 10 μs, and the open circuit voltage is greater than 50V.

9. An efficient horizontal milling type electrochemical machining method for a directional inner-flushing wheel type electrode is characterized by comprising the following steps of: the method comprises the following steps:

and S103, feeding the electrode along a preset track, enabling the movement direction of the outer ring of the electrode at the processing point to be tangential to the surface of the workpiece, and only electrically processing the outer ring, wherein the linear speed of each point is consistent, and finally finishing the processing of the curved surface or the plane.

10. The efficient horizontal milling electrochemical machining method for the directional inner-flushing wheel type electrode, which is disclosed in claim 9, is characterized in that: in step S102, when the electrochemical machining mode is adopted, a direct current power supply is adopted, the current is greater than 1A, and the voltage is not greater than 40V.