A wheel-type electrorheological polishing apparatus and a polishing method

Abstract

The present application relates to a kind of wheel electrorheological polishing equipment and polishing method.The equipment includes wheel electrode, wheel electrode insulation board, electrode and insulation base, wheel electrode diameter is greater than the diameter of wheel electrode insulation board, wheel electrode is two, is installed in the two sides of wheel electrode insulation board, electrorheological polishing fluid is located in the slit formed by two wheel electrodes;The boss on wheel electrode insulation board is matched with the installation groove on wheel electrode, the boss and the surface of wheel electrode are provided with spherical annular groove, and the electrode is installed on the one end of insulation base in spherical annular groove.Compared with prior art, the present application has the advantages that electrorheological polishing fluid is fixed in the slit under the action of electric field, the polishing of workpiece is realized;Electrode is periodically contacted with conductive material and insulating material, and the renewal of electrorheological polishing fluid is realized;Ball head carbon brush is installed on L-shaped pole plate through elastic element, and the stable rotation of wheel electrode is guaranteed.

Description

Technical Field

[0001] This invention relates to polishing equipment, and more particularly to a wheel-type electrorheological polishing device and polishing method. Background Technology

[0002] With the increasing demands on product performance in modern manufacturing, higher requirements are being placed on the surface finish of metal parts in many fields (or situations), such as achieving sub-nanometer surface roughness, arcsecond-level surface accuracy, stress-free operation, and no subsurface damage. However, due to the lag in polishing technology and the unique characteristics of the materials and structures of the metal parts being polished, ultra-precision machining of some metal parts faces significant challenges, especially for rotating parts with large aspect ratios, where the maturity of polishing technology and the processing difficulty are self-evident. Therefore, exploring a flexible polishing technology suitable for rotating parts is of great significance.

[0003] Currently, polishing technologies for rotating parts mainly include traditional mechanical polishing, electrolytic polishing, chemical mechanical polishing, abrasive polishing, and rheology fluid-assisted polishing. Traditional mechanical polishing is the most commonly used processing technology, primarily achieving polishing through direct physical contact between the tool and the workpiece. This technology has advantages such as simple equipment and high polishing efficiency, but it generates internal stress on the workpiece surface, and in more severe cases, may cause subsurface damage, which may reduce the final performance and service life of the product. Electrolytic machining is a surface treatment technology based on anodic dissolution, with many irreplaceable advantages, such as no altered layer, no internal stress, and no tool wear. It polishes the workpiece surface in ionic form, but because alloy materials often contain many non-metallic elements, it is difficult to maintain a consistent material removal rate throughout the metal workpiece. Chemical mechanical polishing is a relatively mature polishing process that combines chemical oxidation with high mechanical shear to remove material from the metal workpiece surface. Compared to mechanical polishing, this technology significantly improves both polishing efficiency and quality. Its disadvantages include uncontrollable oxide layer thickness, leading to uncontrollable material removal rate, and the polishing solution being non-reusable and causing significant environmental pollution. Grinding and polishing is a machining technique that uses an abrasive tool to compress abrasive particles between itself and a workpiece to achieve a smooth surface. Grinding and polishing produces relatively high-quality results, and is particularly suitable for polishing flat surfaces or surfaces with very small curvature. However, it cannot be used to polish some rotating metal parts with large aspect ratios.

[0004] Compared to the above polishing technologies, magnetorheological polishing and electrorheological polishing are the most promising polishing technologies. Both rely on an external field to cause the intelligent fluid to undergo a liquid-solid phase transition to achieve polishing. Magnetorheological polishing relies on a magnetic field generator to magnetize the magnetorheological fluid. Adjusting the magnetic field strength can achieve high shear strength. However, for rotating parts, due to the inconsistent curvature of various points on the metal workpiece, it is difficult to ensure that the magnetic field strength at each point is consistent. In addition, the size of the polishing wheel is relatively large compared to the size of the electrorheological tool electrode. For polishing rotating parts, electrorheological polishing has the following advantages: (1) The electrode structure is simple, and it is easy to achieve uniform electric field strength to adapt to the polishing of rotating parts with various curvatures; (2) The size and structure of the electrorheological tool electrode can be adjusted according to the polishing and shaping area; (3) The electrorheological electric field strength can be infinitely adjusted for shear strength by means of an external electric field; (4) Similar to magnetorheological polishing, it has flexible polishing performance. However, during the electrorheological polishing process, the workpiece debris will be embedded in the polishing fluid, which will not only affect the renewal of the polishing fluid, but also reduce the shear strength and polishing stability of the polishing fluid.

[0005] A search revealed that application publication number CN116985026A discloses a waterwheel-type electrorheological polishing electrode and a polishing machine. Specifically, the polishing electrode has multiple protrusions on its outer surface, a circular cross-section, and the protrusions are circumferentially distributed on its outer circumference. The end faces of the protrusions furthest from the center of the polishing electrode are arc-shaped. However, this prior art is only applicable to polishing conductive materials.

[0006] In summary, the technical problem to be solved is how to design an electrorheological polishing device that can update the polishing slurry and is applicable not only to conductive materials. Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of the existing technology, such as the large amount of workpiece debris in the polishing slurry and its inapplicability to various workpiece materials, and to provide a wheel-type electrorheological polishing device and polishing method.

[0008] The objective of this invention can be achieved through the following technical solutions:

[0009] According to one aspect of the present invention, a wheel-type electrorheological polishing device is provided, comprising a wheel electrode, a wheel electrode insulating plate, an electrode, and an insulating base. The wheel electrode and the wheel electrode insulating plate are disc-shaped, and the diameter of the wheel electrode is larger than the diameter of the wheel electrode insulating plate. There are two wheel electrodes, which are coaxially mounted on both sides of the wheel electrode insulating plate. The electrorheological polishing fluid is located in the slit formed by the two wheel electrodes. The wheel electrode insulating plate is symmetrically provided with multiple bosses on both sides. The wheel electrode is provided with a mounting groove, which cooperates with the bosses. The surfaces of the bosses and the wheel electrodes away from the wheel electrode insulating plate are located in the same plane, and the bosses and the wheel electrodes are provided with spherical annular grooves concentric with the wheel electrodes in this plane. There are two electrodes, one end of which is located in the spherical annular grooves of the two wheel electrodes respectively. The electrodes are mounted on the insulating base.

[0010] As a preferred technical solution, the electrode includes a ball-shaped carbon brush and an L-shaped electrode plate. One end of the ball-shaped carbon brush is located in a spherical annular groove, and the other end is mounted on the L-shaped electrode plate, which is mounted on an insulating base.

[0011] As a preferred technical solution, the radius of the ball head of the ball-shaped carbon brush is smaller than the diameter of the spherical annular groove, and the ball-shaped carbon brush is mounted on the L-shaped electrode plate by an elastic element.

[0012] As a preferred technical solution, the L-shaped electrode plate and the insulating base are installed through bolt mounting holes, and the insulating base is provided with base fixing holes.

[0013] As a preferred technical solution, the thickness of the wheel-type electrode insulating plate is 0.3mm to 1mm.

[0014] As a preferred technical solution, the plurality of bosses are evenly distributed on the surface of the wheel electrode insulating plate.

[0015] As a preferred technical solution, the thickness of the wheel electrode is greater than the radius of curvature of the spherical annular groove.

[0016] As a preferred technical solution, the wheel electrode and the wheel electrode insulating plate are bonded together with adhesive.

[0017] As a preferred technical solution, the wheel electrode and the wheel electrode insulating plate are provided with shaft holes, and keyways are provided in the shaft holes.

[0018] According to another aspect of the present invention, a polishing method using a wheel-type electrorheological polishing device is provided, specifically comprising the following steps:

[0019] Step S1: Connect the positive and negative terminals of the external power supply to the two electrodes respectively;

[0020] Step S2: The electrorheological polishing slurry is fixed in the slit under the action of the electric field formed by the wheel electrode;

[0021] Step S3: The wheel electrode insulating plate and the wheel electrode rotate;

[0022] Step S4: The wheel electrode is brought close to the workpiece to be polished to polish the workpiece.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1) In this invention, a slit is formed between the disc-shaped wheel electrode insulating plate and the wheel electrode. The electrorheological polishing fluid is fixed in the slit under the action of the electric field formed by the wheel electrode. The wheel electrode rotates to achieve polishing of the workpiece by the electrorheological polishing fluid. The electrode slides in the boss of the wheel electrode insulating plate and the spherical annular groove on the surface of the wheel electrode, and makes periodic contact with the conductive material and the insulating material respectively, which can realize the renewal of the electrorheological polishing fluid. The two wheel electrodes serve as two poles, without the workpiece as one pole, making it suitable for polishing various materials.

[0025] 2) The ball-head carbon brush of the present invention is mounted on the L-shaped electrode plate by an elastic element, which can ensure the smooth rotation of the wheel electrode;

[0026] 3) The thickness of the wheel electrode insulating plate of the present invention is 0.3mm to 1mm, which can prevent the problem of breakdown caused by being too thin, and also ensure conductivity and ensure the polishing ability of electrorheological polishing liquid; the bosses are evenly distributed on the surface of the wheel electrode insulating plate, which facilitates the adjustment of discharge time and discharge interval. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the overall structure of a wheel-type electrorheological polishing device according to the present invention;

[0028] Figure 2 This is a graph showing the voltage across the wheel-shaped electrode of the present invention changing over time.

[0029] The numbers in the diagram are as follows:

[0030] 1. Wheel electrode; 10. Spherical annular groove; 2. Wheel electrode insulating plate; 20. Boss; 30. Ball head carbon brush; 31. L-shaped electrode plate; 310. Bolt mounting hole; 4. Insulating base; 40. Base fixing hole; 5. Shaft hole; 50. Keyway. Detailed Implementation

[0031] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0032] Example 1

[0033] like Figure 1 As shown, the present invention provides a wheel-type electrorheological polishing device, which includes a power supply system and a tool electrode; the tool electrode includes two wheel electrodes 1 and a wheel electrode insulating plate 2; the power supply system includes electrodes and an insulating base 4.

[0034] The wheel electrode insulating plate 2 is made of insulating materials such as nylon or plexiglass, while the wheel electrode 1 is made of conductive materials such as stainless steel, brass, or aluminum alloy. Both wheel electrodes 1 and the wheel electrode insulating plate 2 are disc-shaped, with the diameter of the wheel electrode 1 being larger than the diameter of the wheel electrode insulating plate 2. The two wheel electrodes 1 are symmetrically mounted on the two surfaces of the wheel electrode insulating plate 2 using an adhesive bonding method, forming a slit between the two wheel electrodes 1. The electrorheological polishing fluid is located in the slit formed by the two wheel electrodes 1.

[0035] Both surfaces of the wheel electrode insulating plate 2 are symmetrically designed with several discontinuous rectangular bosses 20. The wheel electrode 1 has a mounting groove with the same shape as the bosses 20. The mounting groove and the bosses 20 are fitted together for easy installation and positioning of the wheel electrode 1. The surface of the bosses 20 away from the wheel electrode insulating plate 2 and the surface of the wheel electrode 1 away from the wheel electrode insulating plate 2 are located in the same plane. The wheel electrode 1 and the bosses 20 are integrally designed with a continuous spherical annular groove 10 on this surface. The spherical annular groove 10 is coaxial with the wheel electrode 1. The thickness of the wheel electrode 1 is greater than the radius of curvature of the spherical annular groove 10, so that the semicircle of the spherical annular groove 10 can be completely embedded in the wheel electrode 1. During installation, the two wheel electrodes 1 and the wheel electrode insulating plate 2 are first fixed as a whole by the bosses 20 and the mounting groove. Then, the spherical annular groove with alternating insulating and conductive phases is machined on the surface by mechanical processing.

[0036] The insulation plate of the wheel electrode 1 has a thickness of 0.3mm to 1mm to ensure a certain discharge gap and to ensure the polishing ability of the electrorheological polishing fluid. If the thickness is too thin, it is easy to cause breakdown. If the thickness is too thick, the conductivity will be poor.

[0037] The wheel electrode 1 and the wheel electrode insulating plate 2 are provided with shaft holes 5, and the shaft holes 5 are designed with keyways 50 for transmitting torque. The wheel electrode 1 and the wheel electrode insulating plate 2 rotate under the action of torque through the keyways 50.

[0038] There are two electrodes, each in contact with a wheel-shaped electrode 1. Each electrode includes a ball-head carbon brush 30 and an L-shaped electrode plate 31. The ball-head carbon brush 30 has a ball-head structure with a radius smaller than the diameter of the spherical annular groove 10, and the ball-head is located within the spherical annular groove 10. The ball-head carbon brush 30 is mounted on one end of the L-shaped electrode plate 31 via an elastic element (such as a spring) to ensure smooth rotation of the wheel-shaped electrode 1. The L-shaped electrode plate 31 is made of metal, and its other end is mounted on an insulating base plate and connected to the insulating base plate via bolt mounting holes 310. The positive and negative terminals of the external power supply are also connected to the L-shaped electrode plate 31 via bolt mounting holes 310.

[0039] The insulating base 4 is made of insulating material and has base fixing holes 40. The entire device is fixed through the base fixing holes 40.

[0040] Example 2

[0041] This invention provides a wheel-type electrorheological polishing method, which is implemented by the following steps:

[0042] Step 1: Power supply. Connect the positive and negative terminals of the external power supply to the left and right bolt mounting holes 310 using bolts.

[0043] Step 2: Liquid supply. The polishing liquid is fixed in the annular gap under the action of an external electric field.

[0044] Step 3: Rotation. The wheel electrode 1 and the wheel electrode insulating plate 2 rotate as a whole under the torque of the keyway 50.

[0045] Step 4: Polishing. The wheel electrode 1 and the wheel electrode insulating plate 2 are brought close to the workpiece to be polished. At this time, the wheel electrode 1 acts similarly to a grinding wheel. When the wheel electrode 1 rotates relative to the power supply system, the ball-head carbon brush 30 makes periodic contact with the conductive and insulating materials to achieve intermittent discharge. The voltage change across the wheel electrode 1 is as follows: Figure 2 As shown, when the gap between the wheel electrodes 1 is filled with electrorheological polishing fluid and the workpiece and the wheel electrodes 1 rotate simultaneously, ultra-precision polishing of the workpiece can be achieved.

[0046] In traditional electrorheological polishing, metal debris becomes embedded in the surface of the flexible polishing head formed by the electrorheological fluid, easily causing insulation breakdown and affecting polishing stability and processing quality. This invention can refresh the electrorheological polishing fluid, reducing the probability of insulation breakdown, improving processing stability, enhancing surface finish, eliminating caking, and is suitable for polishing workpieces of different materials (conductive or non-conductive) and shapes (e.g., rotating bodies, planar surfaces, or small radius of curvature structures). When the wheel electrode 1 and wheel electrode insulating plate 2 rotate, the ball-head carbon brush periodically contacts the wheel electrode 1 and wheel electrode insulating plate 2, enabling control of discharge time and interval. It has a pulsed power supply intermittent discharge function to refresh the electrorheological polishing fluid. The refresh time of the electrorheological fluid can be controlled by adjusting the ratio of discharge time to discharge interval. Furthermore, the small discharge gap of the wheel electrode 1 (the distance between the two wheel electrodes 1 is the thickness of the wheel electrode insulating plate 2) is beneficial for polishing and reshaping; the over-polishing problem caused by traditional chemical mechanical polishing can be solved by adjusting the discharge gap of the wheel electrode 1. The present invention has a simple structure and can be designed in a modular manner.

[0047] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A wheel-type electrorheological polishing device, characterized in that, The assembly includes a wheel electrode (1), a wheel electrode insulating plate (2), electrodes, and an insulating base (4). The wheel electrode (1) and the wheel electrode insulating plate (2) are disc-shaped, and the diameter of the wheel electrode (1) is larger than the diameter of the wheel electrode insulating plate (2). There are two wheel electrodes (1), which are coaxially mounted on both sides of the wheel electrode insulating plate (2). The electrorheological polishing fluid is located in the slit formed by the two wheel electrodes (1). The wheel electrode insulating plate (2) has multiple protrusions (20) symmetrically arranged on both sides. The wheel electrode (1) is provided with a mounting groove, which cooperates with the boss (20). The surfaces of the boss (20) and the wheel electrode (1) away from the wheel electrode insulating plate (2) are located in the same plane. The boss (20) and the wheel electrode (1) are provided with a spherical annular groove (10) concentric with the wheel electrode (1) in the plane. There are two electrodes, one end of which is located in the spherical annular groove (10) of the two wheel electrodes (1). The electrodes are mounted on the insulating base (4).

2. The wheel-type electrorheological polishing equipment according to claim 1, characterized in that, The electrode includes a ball-shaped carbon brush (30) and an L-shaped electrode plate (31). One end of the ball-shaped carbon brush (30) is located in a spherical annular groove (10), and the other end is mounted on the L-shaped electrode plate (31). The L-shaped electrode plate (31) is mounted on an insulating base (4).

3. The wheel-type electrorheological polishing device according to claim 2, characterized in that, The ball head radius of the ball head carbon brush (30) is smaller than the diameter of the spherical annular groove (10), and the ball head carbon brush (30) is mounted on the L-shaped electrode plate (31) by means of an elastic element.

4. The wheel-type electrorheological polishing device according to claim 2, characterized in that, The L-shaped electrode plate (31) and the insulating base (4) are installed through bolt mounting holes (310), and the insulating base (4) is provided with base fixing holes (40).

5. The wheel-type electrorheological polishing device according to claim 1, characterized in that, The thickness of the wheel-type electrode insulating plate (2) is 0.3mm to 1mm.

6. The wheel-type electrorheological polishing device according to claim 1, characterized in that, The multiple bosses (20) are evenly distributed around the circumference of the wheel electrode insulating plate (2).

7. The wheel-type electrorheological polishing device according to claim 1, characterized in that, The thickness of the wheel electrode (1) is greater than the radius of curvature of the spherical annular groove (10).

8. The wheel-type electrorheological polishing device according to claim 1, characterized in that, The wheel electrode (1) and the wheel electrode insulating plate (2) are bonded together.

9. The wheel-type electrorheological polishing device according to claim 1, characterized in that, The wheel electrode (1) and the wheel electrode insulating plate (2) are provided with shaft holes (5), and keyways (50) are provided in the shaft holes (5).

10. A polishing method using the wheel-type electrorheological polishing equipment as described in claim 1, characterized in that, Specifically, the following steps are included: Step S1: Connect the positive and negative terminals of the external power supply to the two electrodes respectively; Step S2: The electrorheological polishing slurry is fixed in the slit under the action of the electric field formed by the wheel electrode (1); In step S3, the wheel electrode insulating plate (2) and the wheel electrode (1) rotate; Step S4: The wheel electrode (1) is brought close to the workpiece to be polished to polish the workpiece.

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