Pulse dynamic electrolysis discharge mechanical composite milling cathode and method

Abstract

The invention discloses a pulse dynamic electrolysis discharge mechanical composite milling cathode which comprises a cathode base body, a first insulation blade, a second insulation blade, a discharge module, a first insulation blade fixing screw, a discharge module fixing screw and a second insulation blade fixing screw. Three mounting grooves are formed in the end part of the cathode base body, and the two large-opening-angle grooves are used for mounting the first insulating blade and the second insulating blade; the first insulation blade, the second insulation blade and the discharge module are respectively connected with the cathode substrate through a first insulation blade fixing screw, a discharge module fixing screw and a second insulation blade fixing screw. Through coupling of cathode end face functional partition and voltage waveform periodic pulsation, pulse dynamic adjustment of electromachining and machining in the machining process is achieved, the machining efficiency is guaranteed, meanwhile, the adverse effect of the electrolysis effect on the machined surface is effectively avoided, and the surface quality and precision in the machining process are guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of electrostatic discharge and electromechanical composite machining, and in particular to a pulsed electrostatic discharge and electromechanical composite milling machining cathode and method. Background Art

[0002] Materials such as titanium alloys and high-temperature alloys have been widely used in high-tech fields such as aerospace, military industry, and energy due to their excellent strength, high-temperature resistance, and corrosion resistance. However, these materials usually have high hardness and poor cutting performance. When processed using traditional mechanical processing methods, the tool wear is serious, which not only leads to a significant increase in processing costs, but also may make the processed parts unable to meet the required technical requirements, greatly limiting the application and development potential of these materials in related fields.

[0003] Compared with traditional mechanical processing methods, electrochemical machining, as a non-contact processing method, has great advantages in processing such difficult-to-process conductive materials, such as no cutting force, no tool loss and high surface quality. Electrochemical milling technology is a combination of electrochemical machining and CNC technology. It uses a simple tubular cathode to perform electrochemical machining according to a preset trajectory, and reasonable path planning can achieve the processing of complex structures. However, the current electrochemical milling efficiency is low and cannot meet the needs of large-scale and high-efficiency production. Therefore, relying solely on electrochemical milling cannot completely solve the problem of efficient processing.

[0004] In order to solve this bottleneck, researchers combined electrolytic milling with discharge machining technology to form electrolytic-discharge composite milling technology, breaking through the efficiency limitations of traditional electrolytic milling. However, in practical applications, since both electrolytic machining and discharge machining are non-contact machining, their machining accuracy and surface quality are difficult to stably control, which limits the application of this technology in the field of high-precision machining.

[0005] In response to this problem, the invention of patent number 201910274296.9 proposes an innovative solution. This patent introduces mechanical processing into electrolytic discharge composite milling processing, and cuts the electrolytic discharge surface through the rotation of the cathode blade, which can effectively improve the surface quality of the workpiece. However, due to the continuous electrolysis of the cathode in the processing area, the surface after mechanical processing will still be subject to electrolytic corrosion, and the surface quality of the workpiece is difficult to maintain at the level after mechanical milling. Therefore, how to avoid the adverse effects of electrolysis on the machined surface after the introduction of mechanical processing has become a problem that needs to be solved urgently. Summary of the invention

[0006] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0007] In view of the problems existing in the above-mentioned existing pulse dynamic electrostatic discharge electrostatic mechanical composite milling processing cathode and method, the present invention is proposed.

[0008] Therefore, the purpose of the present invention is to provide a pulsed electrolytic electro-mechanical composite milling processing cathode and method, which realizes the pulsed adjustment of electrical machining and mechanical machining during the machining process through the coupling of the functional partitioning of the cathode end surface and the periodic pulsation of the voltage waveform. While ensuring the machining efficiency, it effectively avoids the adverse effects of electrolysis on the machined surface, thereby ensuring the surface quality and precision during the machining process.

[0009] In order to solve the above technical problems, the present invention provides the following technical solutions: a pulsed dynamic electrostatic discharge mechanical composite milling machining cathode, comprising:

[0010] Cathode substrate, first insulating blade, second insulating blade, discharge module, first insulating blade fixing screw, discharge module fixing screw and second insulating blade fixing screw;

[0011] There are three installation grooves at the end of the cathode substrate, two large-angle grooves are used to install the first insulating blade and the second insulating blade, and the small-angle groove is used to fix the discharge module;

[0012] The first insulating blade, the second insulating blade and the discharge module are connected to the cathode substrate by means of the first insulating blade fixing screws, the discharge module fixing screws and the second insulating blade fixing screws respectively.

[0013] As a preferred solution of the pulsed electrolytic discharge electrolytic mechanical composite milling cathode of the present invention, the first insulating blade and the second insulating blade are made of non-conductive ceramic or CBN material.

[0014] As a preferred solution for the pulsed dynamic electrochemical discharge electrochemical mechanical composite milling machining cathode of the present invention, the discharge module is made of graphite, copper tungsten, and cerium tungsten corrosion-resistant materials, and a liquid outlet hole connected to the cathode substrate is opened on the bottom surface for spraying electrolyte.

[0015] As a preferred solution for the pulsed dynamic discharge discharge mechanical composite milling processing cathode of the present invention, wherein: the inner diameter of the fan-shaped bottom surface of the discharge module is larger than the cutting radius of the first insulating blade and the second insulating blade, the height of the bottom surface of the discharge module protruding from the bottom surface of the cathode substrate is smaller than the height of the first insulating blade and the second insulating blade tip protruding from the bottom surface of the cathode substrate, and the height of the three protruding from the bottom surface of the cathode substrate is greater than mm, which can reduce the stray corrosion of the bottom surface of the cathode substrate on the workpiece surface.

[0016] A pulsed electrostatic discharge mechanical composite milling processing method comprises the following steps:

[0017] In a single cathode rotation cycle, when the discharge module rotates to the front of the processing area, the power supply applies voltage between the cathode substrate and the workpiece, generating an electrolytic discharge effect, which removes a large amount of workpiece material in a short time. As the discharge module rotates out of the specified position, the processing circuit is disconnected;

[0018] During the power-on time, the projection range of the discharge module action area in the vertical cathode substrate feeding direction should be included in the actual cutting width of the first insulating blade and the second insulating blade on the workpiece;

[0019] Then the first insulating blade and the second insulating blade continue to cut the electrolytic discharge machining surface to improve the surface quality; the electrolytic discharge machining and mechanical milling machining occur repeatedly with the rotation of the cathode, presenting a pulsating machining state.

[0020] As a preferred solution of the pulsed electrolytic discharge-electromechanical composite milling processing method described in the present invention, the power supply is turned on only when the discharge module is turned to the front of the processing area, and the electrolytic action will not perform secondary processing on the surface after mechanical processing, thereby avoiding stray corrosion.

[0021] As a preferred solution of the pulsed electrolytic discharge mechanical composite milling processing method of the present invention, the electrolyte used in the processing is sodium chloride or sodium nitrate solution with a concentration higher than 10%.

[0022] Beneficial effects of the present invention:

[0023] The present invention adopts a modular and detachable cathode design. The discharge module and the insulating blade are connected to the cathode substrate by screws. They can be replaced in time after being worn to a certain extent, and are easy to disassemble and assemble.

[0024] The present invention realizes pulsed electrolytic electrolytic machining by coupling the functional partitioning of the cathode end surface with the periodic pulsation of the voltage waveform, which improves the machining efficiency and effectively avoids stray corrosion of the machined surface by the electrolytic action, thereby improving the machining accuracy and surface quality.

[0025] The present invention can meet the demand for modulating voltage waveform by using a programmable direct current power supply, without using a high-frequency pulse power supply, thereby reducing the difficulty of synchronization between the voltage waveform and the electrode rotation and having low operating cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

[0027] Figure 1 It is a schematic diagram of the pulse dynamic electrostatic discharge mechanical compound milling processing system;

[0028] Figure 2 This is a schematic diagram of the cathode structure of pulse dynamic electrochemical discharge electrochemical mechanical composite milling processing;

[0029] Figure 3 Exploded diagram of cathode structure in pulse dynamic electrostatic discharge and mechanical composite milling machining

[0030] Figure 4 It is a schematic diagram of the machining gap of pulse dynamic electro-discharge electro-mechanical compound milling;

[0031] Figure 5 Schematic diagram of the periodic coupling of cathode rotation and voltage waveform in pulsed dynamic electrochemical discharge-mechanical composite milling processing. DETAILED DESCRIPTION

[0032] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0033] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0034] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0035] Secondly, the present invention is described in detail with reference to the schematic diagram. When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0036] Reference Figure 1-Figure 5 , provides a pulse dynamic electrostatic discharge electromechanical composite milling machining cathode, including:

[0037] Cathode substrate 1, first insulating blade 2, second insulating blade 3, discharge module 4, first insulating blade fixing screw 5, discharge module fixing screw 6 and second insulating blade fixing screw 7;

[0038] There are three installation grooves at the end of the cathode substrate 1, two large-angle grooves are used to install the first insulating blade 2 and the second insulating blade 3, and the small-angle groove is used to fix the discharge module 4;

[0039] The first insulating blade 2 , the second insulating blade 3 , and the discharge module 4 are connected to the cathode substrate 1 by means of the first insulating blade fixing screws 5 , the discharge module fixing screws 6 , and the second insulating blade fixing screws 7 , respectively.

[0040] The first insulating blade 2 and the second insulating blade 3 are made of non-conductive ceramic or CBN material.

[0041] Furthermore, the discharge module 4 is made of graphite, copper tungsten, and cerium tungsten corrosion-resistant materials, and a liquid outlet 8 connected to the cathode substrate 1 is opened on the bottom surface for spraying electrolyte; specifically, the inner diameter of the fan-shaped bottom surface of the discharge module 4 is larger than the cutting radius of the first insulating blade 2 and the second insulating blade 3, and the height of the bottom surface of the discharge module 4 protruding from the bottom surface of the cathode substrate 1 is smaller than the height of the tips of the first insulating blade 2 and the second insulating blade 3 protruding from the bottom surface of the cathode substrate 1, and the heights of the three protruding from the bottom surface of the cathode substrate 1 are all greater than 3 mm, which can reduce the stray corrosion of the bottom surface of the cathode substrate 1 on the workpiece surface.

[0042] like Figure 1 As shown, during processing, the cathode of a pulsed electrolytic discharge and electromechanical composite milling processing proposed by the present invention is connected to the negative electrode of the power supply, and the workpiece is connected to the positive electrode of the power supply. The electrolyte enters from the inner hole of the cathode and is sprayed to the processing area. The cathode rotates and feeds forward to perform electrolytic discharge and electromechanical composite milling processing.

[0043] like Figure 2 and Figure 3As shown, a pulsed dynamic discharge discharge mechanical composite milling machining cathode proposed by the present invention comprises a cathode base 1, a first insulating blade 2, a second insulating blade 3, a discharge module 4, a first insulating blade fixing screw 5, a discharge module 4 fixing screw and a second insulating blade fixing screw 7; there are three mounting grooves at the end of the cathode base 1, two large opening angle grooves are used to install the first insulating blade 2 and the second insulating blade 3, and the small opening angle groove is used to fix the discharge module 4; the first insulating blade 2, the second insulating blade 3, and the discharge module 4 are connected to the cathode base 1 by means of the first insulating blade fixing screw 5, the discharge module fixing screw 6 and the second insulating blade fixing screw 7 respectively;

[0044] Figure 4 The inter-electrode gap of pulsed electrolytic discharge and mechanical composite milling is shown. When the discharge module 4 is rotated to the front of the processing area, a discharge channel is generated between the discharge module 4 and the workpiece 9, realizing the discharge discharge and composite processing, and efficiently removing the workpiece material. The height of the discharge module 4 protruding from the bottom of the cathode is less than the height of the first insulating blade 2 and the second insulating blade 3 protruding from the bottom of the workpiece, thereby ensuring that a certain processing allowance is left for mechanical milling after discharge electrolytic processing.

[0045] Reference Figure 5 Through the cathode end face partition design, the two processing technologies of mechanical processing and electrolytic discharge machining are coupled together, and the entire processing presents a periodic pulsation. The cathode has a rotation angular velocity of ω. Within a single cathode rotation period T, when the discharge module 4 rotates to the front processing area (angle is φ1), the power supply 14 is turned on to generate an electrolytic discharge effect, and a large amount of workpiece material is etched away in a short time. When it rotates out of the specified position (angle is φ2), the circuit is disconnected, and the first insulating blade 2 and the second insulating blade 3 subsequently cut the electrolytic discharge machining surface to improve the surface quality.

[0046] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A pulsed electrostatic discharge mechanical composite milling cathode, characterized in that: include: A cathode base (1), a first insulating blade (2), a second insulating blade (3), a discharge module (4), a first insulating blade fixing screw (5), a discharge module fixing screw (6) and a second insulating blade fixing screw (7); The cathode substrate (1) has three mounting grooves at its end, two large-angle grooves are used to mount the first insulating blade (2) and the second insulating blade (3), and the small-angle groove is used to fix the discharge module (4); The first insulating blade (2), the second insulating blade (3) and the discharge module (4) are connected to the cathode base (1) respectively by means of the first insulating blade fixing screw (5), the discharge module fixing screw (6) and the second insulating blade fixing screw (7).

2. The pulsed electrostatic discharge electrostatic mechanical composite milling cathode according to claim 1, characterized in that: The first insulating blade (2) and the second insulating blade (3) are made of non-conductive ceramic or CBN material.

3. The pulsed electrostatic discharge electrostatic mechanical composite milling cathode according to claim 1, characterized in that: The discharge module (4) is made of graphite, copper tungsten, or cerium tungsten electro-corrosion resistant materials, and has a bottom surface with a liquid outlet (8) connected to the cathode substrate (1) for spraying electrolyte.

4. The pulsed electrostatic discharge electrostatic mechanical composite milling cathode according to claim 3 is characterized in that: The inner diameter of the fan-shaped bottom surface of the discharge module (4) is greater than the cutting radius of the first insulating blade (2) and the second insulating blade (3); the height of the bottom surface of the discharge module (4) protruding from the bottom surface of the cathode substrate (1) is less than the height of the blade tips of the first insulating blade (2) and the second insulating blade (3) protruding from the bottom surface of the cathode substrate (1); and the heights of the three protruding from the bottom surface of the cathode substrate (1) are all greater than 3 mm, thereby reducing stray corrosion of the bottom surface of the cathode substrate (1) on the surface of the workpiece.

5. A pulsed electrostatic discharge mechanical composite milling method, characterized in that: The following steps are involved: In a single cathode rotation cycle, when the discharge module (4) rotates to the front of the processing area, the power supply (14) applies voltage between the cathode substrate (1) and the workpiece (9), generating an electrolytic discharge effect, and removing a large amount of workpiece material in a short time. As the discharge module (4) rotates out of the specified position, the processing circuit is disconnected; During the power-on time, the projection range of the discharge module (4) action area in the vertical cathode substrate (1) feed direction should be included in the actual cutting width of the first insulating blade (2) and the second insulating blade (3) on the workpiece; Then, the first insulating blade (2) and the second insulating blade (3) continue to cut the electrolytic discharge machining surface to improve the surface quality; the electrolytic discharge machining and mechanical milling machining occur repeatedly as the cathode rotates, presenting a pulsating machining state.

6. The pulsed electrolytic discharge and electromechanical composite milling method according to claim 5, characterized in that: The power supply is turned on only when the discharge module is turned to the front of the processing area. The electrolytic action will not perform secondary processing on the machined surface, avoiding stray corrosion.

7. The pulsed electrolytic discharge and electromechanical composite milling method according to claim 5, characterized in that: The electrolyte used in the process is sodium chloride or sodium nitrate solution with a concentration higher than 10%.

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