A magnetorheological finishing processing system

Abstract

The magnetorheological polishing processing system provided by the present invention includes a robotic arm, a workpiece fixing device installed at one end of the robotic arm, and a workbench having a magnetorheological polishing wheel and a magnetorheological circulation system. The magnetorheological circulation system supplies magnetorheological fluid to the magnetorheological polishing wheel. The workbench is installed on the base, and the magnetorheological polishing wheel extends out of the workbench. The workpiece fixing device realizes the position change with the magnetorheological polishing wheel under the drive of the robotic arm. By utilizing the advantages of the multi-degree-of-freedom, speed, and acceleration of the robotic arm in space, and combining the magnetorheological polishing wheel arranged on the workbench, the load on the robotic arm can be reduced, making the robotic arm operate more flexibly during processing. Moreover, a magnetorheological polishing wheel with a larger diameter and greater weight can also be used for processing, making the processing efficient and fast, and further improving the overall efficiency of grinding and polishing.

Description

Technical Field

[0001] The invention relates to the field of optical precision machining, and in particular to a magnetorheological polishing system. Background Art

[0002] With the development of modern science and technology, higher and higher requirements are put forward for optical components used in various optical systems. Generally, the final optical components are required to have high surface accuracy, good surface quality and minimize the subsurface damage layer. High surface accuracy can ensure good imaging quality, smooth surface can reduce scattering, and low subsurface damage layer can avoid damage in high-energy applications. Therefore, the performance of optical components depends to a large extent on the manufacturing process. A variety of processing methods have been studied to obtain high-precision processing surfaces, among which typical processing methods include plastic grinding, chemical polishing, float polishing, elastic emission processing, particle beam polishing, jet polishing, etc. These processing methods either have too low polishing efficiency, or produce a large subsurface damage layer, or polishing is difficult to control, and each has certain defects.

[0003] Magnetorheological fluid is a suspended liquid with controllable rheological behavior formed by dispersing micron-sized magnetic particles in an insulating carrier liquid. Its rheological properties change with the external magnetic field. When there is no magnetic field, the rheological properties of magnetorheological fluid are similar to those of ordinary Newtonian fluids. When subjected to a magnetic field of a certain intensity, it can produce a significant magnetorheological effect under the action of the magnetic field. Its apparent viscosity coefficient increases by more than 2 orders of magnitude and becomes a solid-like state. Once the magnetic field is removed, it becomes a liquid that can flow. The magnetorheological effect under the action of the magnetic field causes the magnetorheological fluid to convert between liquid and solid, and it has the advantages of reversibility, controllability, and rapid response. The shear yield stress of magnetorheological fluid is one order of magnitude larger than that of electrorheological fluid, and magnetorheological fluid has good dynamic and temperature stability, so it has a wider range of applications.

[0004] The existing magnetorheological polishing machining center mainly integrates the magnetorheological polishing module into the cradle-type CNC machine tool. However, since CNC machine tools generally use linear axes to realize motion feeding, there are many limitations in terms of motion speed, acceleration and degrees of freedom. Summary of the invention

[0005] In view of this, an embodiment of the present invention provides a magnetorheological polishing processing system, which utilizes the six degrees of freedom, speed and acceleration advantages of the robotic arm and combines the magnetorheological polishing wheel set on the workbench to reduce the load-bearing capacity of the robotic arm, making the robotic arm more flexible during processing, and can also use magnetorheological polishing wheels with larger diameter and heavier weight for processing, making the processing more efficient and high-speed, and further improving the overall efficiency of grinding and polishing. At the same time, for the same processing range, the system cost is much lower than that of a gantry or cradle-type machining center.

[0006] A magnetorheological polishing processing system provided by the present invention includes a robotic arm, a workpiece fixing device installed at one end of the robotic arm, and a workbench having a magnetorheological polishing wheel and a magnetorheological circulation system. The magnetorheological circulation system supplies magnetorheological fluid to the magnetorheological polishing wheel. The magnetorheological polishing wheel extends out of the workbench. The workpiece fixing device realizes a position change with the magnetorheological polishing wheel under the drive of the robotic arm.

[0007] Optionally, the robotic arm is a robotic arm with six degrees of freedom.

[0008] Optionally, the workpiece fixing device adopts a vacuum chuck.

[0009] Optionally, the vacuum chuck includes a suction cup, a suction cup hoop, a connecting pipe, and a vacuum generator. The suction cup is communicated with the vacuum generator through the connecting pipe. The suction cup hoop is installed at the end of the robotic arm and abuts against the suction cup. The vacuum generator is arranged on the robotic arm.

[0010] Optionally, the magnetorheological circulation system includes a liquid storage tank, a stirrer arranged in the liquid storage tank, a delivery pump, a recovery pump, and a circulation supply loop. The circulation supply loop includes a liquid injection pipe and a recovery pipe communicated with the liquid storage tank, a nozzle arranged at the end of the liquid injection pipe, and a collector arranged at the end of the recovery pipe. The delivery pump is arranged on the liquid injection pipe. The recovery pump is arranged on the recovery pipe. The nozzle and the collector are respectively symmetrically arranged on the robotic arm on both sides of the magnetorheological polishing wheel.

[0011] Optionally, the nozzle is aligned with the edge of the magnetorheological polishing wheel.

[0012] Optionally, the nozzle is aligned with the tangential direction of the magnetorheological polishing wheel.

[0013] Optionally, there is a fit or a gap between the collector and the magnetorheological polishing wheel.

[0014] Optionally, the telescopic direction of the robotic arm is parallel to the plane where the magnetorheological polishing wheel is located.

[0015] Optionally, the magnetorheological circulation system further includes a pressure and flow rate measuring device, and the pressure and flow rate measuring device is communicated with the liquid injection pipe.

[0016] The magnetorheological polishing processing system provided by the present invention includes a robotic arm, a workpiece fixing device installed at one end of the robotic arm, and a workbench having a magnetorheological polishing wheel and a magnetorheological circulation system. The magnetorheological circulation system supplies magnetorheological fluid to the magnetorheological polishing wheel. The magnetorheological polishing wheel extends out of the workbench. The workpiece fixing device realizes a position change with the magnetorheological polishing wheel under the drive of the robotic arm. By utilizing the advantages of the multi-degree-of-freedom, speed, and acceleration of the robotic arm in space, and combining the magnetorheological polishing wheel arranged on the workbench, the load on the robotic arm can be reduced, making the robotic arm operate more flexibly during processing. Moreover, a magnetorheological polishing wheel with a larger diameter and greater weight can also be used for processing, making the processing efficient and fast, and further improving the overall efficiency of grinding and polishing. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 FIG. is a schematic structural diagram of the magnetorheological polishing processing system provided in an embodiment of the present invention.

[0018] Reference numerals: robotic arm 1, magnetorheological polishing wheel 2, workpiece fixing device 3, base 4, workbench 5, workpiece 6. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

[0020] The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products, or devices.

[0021] Principle of magnetorheological polishing fluid: Magnetorheological fluid is a suspension composed of magnetic particles, base fluid, and stabilizer. The magnetorheological effect refers to the phenomenon that magnetorheological fluid is a flowable liquid without a magnetic field, but under the action of a strong magnetic field, its rheological properties change sharply, showing properties similar to those of a solid, and returning to its flow characteristics when the magnetic field is removed. Magnetorheological polishing technology precisely utilizes the rapid relative movement between the flexible "small grinding head" with viscoplastic behavior formed by the rheology of magnetorheological polishing fluid in a gradient magnetic field and the workpiece, so that the workpiece surface is subjected to a large shear force, thereby removing the workpiece surface material. Magnetorheological polishing (MRF) is a comprehensive technology formed by applying electromagnetic theory, fluid mechanics, analytical chemistry, etc. to optical surface processing. Magnetorheological fluid is an intelligent material that can achieve reversible conversion between solid-liquid two phases within 1 ms under the action of a magnetic field.

[0022] A magnetorheological polishing processing system provided by the present invention includes a robotic arm 1, a workpiece fixing device 3 installed at one end of the robotic arm 1, and a workbench 5 having a magnetorheological polishing wheel 2 and a magnetorheological circulation system (not shown in the figure). The magnetorheological circulation system supplies magnetorheological fluid to the magnetorheological polishing wheel 2. The magnetorheological polishing wheel 2 extends out of the workbench 5. The workpiece fixing device 3 realizes a position change with respect to the magnetorheological polishing wheel 2 under the drive of the robotic arm 1, that is, the workpiece 6 is polished on the magnetorheological polishing wheel 2 under the drive of the robotic arm 1 under the control of a motion program. By changing the position of the workpiece fixing device 3, the position change of the workpiece 6 on the magnetorheological polishing wheel 2 is realized to achieve uniform polishing. The magnetorheological polishing wheel 3 is used for material removal. At the same time, the magnetorheological circulation system embedded in the workbench 5 realizes liquid supply and circulation support for the magnetorheological polishing wheel 2 to ensure the normal operation of the magnetorheological system.

[0023] The direction in which the magnetorheological polishing wheel 2 extends out of the workbench 5 can be the side or the top. In this embodiment, the way that the magnetorheological polishing wheel 2 extends out of the top of the workbench 5 can be adopted, and specific limitations are not made.

[0024] Adopting the upright structure of the magnetorheological polishing wheel 2, the robotic arm 1 does not need to drive the magnetorheological polishing wheel 2 to move, reducing the load on the robotic arm. A magnetorheological polishing wheel 2 with a larger diameter and greater weight can be used to process the workpiece, and larger-sized workpieces can be polished, thereby improving the polishing efficiency.

[0025] In this embodiment, the robotic arm 1 is used to drive the workpiece 6 on the workpiece fixing device 3 for processing on the workpiece fixing device 3 of the workbench 5. In order to better provide multiple processing angles, the robotic arm 1 can adopt a robotic arm 1 with six degrees of freedom. Of course, a robotic arm 1 with other degrees of freedom can also be selected according to needs as long as the position change of the workpiece fixing device 3 with respect to the magnetorheological polishing wheel 2 can be realized.

[0026] Optionally, the workpiece fixing device 3 adopts a vacuum chuck. The material of the vacuum chuck can be polyurethane, silicone rubber, nitrile rubber or vinyl-containing polymer. The rubber-made chuck can be operated at high temperatures. The silicone rubber-made chuck is very suitable for gripping products with rough surfaces, and the polyurethane-made chuck is very durable. Additionally, in actual production, if the chuck is required to have oil resistance, materials such as polyurethane, nitrile rubber or vinyl-containing polymer can be considered for manufacturing the chuck. Generally, to avoid scratching the surface of the product, it is best to choose a chuck with a bellows made of nitrile rubber or silicone rubber. The chuck material is made of nitrile rubber, which has a large breaking strength and can be flexibly selected according to needs, and no limitation is made thereto.

[0027] The vacuum chuck includes a chuck, a chuck hoop, a connecting pipe and a vacuum generator. The chuck is communicated with the vacuum generator through the connecting pipe. The chuck hoop is installed at the end of the robotic arm 1 and abuts against the chuck. The vacuum generator is arranged on the robotic arm 1. After connecting the chuck to the vacuum generator through a connecting pipe, the robotic arm 1 drives the chuck to contact the workpiece 6, starts the vacuum generator to suck, so that a negative air pressure is generated in the chuck, and the workpiece 6 is firmly sucked under the action of the chuck hoop, and then the machining of the workpiece 6 can be started. When the machining of the workpiece 6 is completed, the workpiece 6 is moved to the placement area, and air is smoothly inflated into the chuck to make the air pressure in the chuck change from negative to zero or slightly positive, and the chuck is separated from the workpiece 6, thus completing the fixing function of the workpiece 6.

[0028] For the structure of the magnetorheological circulation system, in an embodiment provided by the present invention, the magnetorheological circulation system includes a liquid storage tank, a stirrer arranged in the liquid storage tank, a delivery pump, a recovery pump and a circulation supply loop. The circulation supply loop includes a liquid injection pipe and a recovery pipe communicated with the liquid storage tank, a nozzle arranged at the end of the liquid injection pipe and a collector arranged at the end of the recovery pipe. The delivery pump is arranged on the liquid injection pipe. The recovery pump is arranged on the recovery pipe. The nozzle and the collector are respectively symmetrically arranged on the robotic arm 1 on both sides of the magnetorheological polishing wheel 2. There is a fit or a gap between the collector and the polishing wheel. By adopting this structure, the magnetorheological fluid can be contacted with the polishing wheel and a certain amount can be recovered, meeting the needs of normal fine machining and reducing the loss of the magnetorheological fluid.

[0029] The magnetorheological circulation system further includes a pressure and flow rate measuring device, and the pressure and flow rate measuring device is communicated with the liquid injection pipe to measure the pressure and flow rate of the magnetorheological fluid in the liquid injection pipe.

[0030] To better facilitate the contact between the magnetorheological fluid and the magnetorheological polishing wheel 2, the spraying direction of the nozzle is aligned with the edge of the magnetorheological polishing wheel 2, so that the magnetorheological fluid ejected from the nozzle directly contacts the polishing wheel. In a more preferred solution, the nozzle can be aligned with the tangential direction of the magnetorheological polishing wheel 2. It should be noted that the spraying angle of the nozzle can be adjusted according to actual needs and is not limited in this regard.

[0031] The telescopic direction of the robotic arm 1 is parallel to the plane where the magnetorheological polishing wheel 2 is located. The robotic arm 1 can drive the workpiece 2 to perform processing operations on the magnetorheological polishing wheel 2, which can, to a certain extent, shorten the movement stroke of the robotic arm and improve the processing efficiency.

[0032] The workbench 5 has a housing, and the magnetorheological circulation system is arranged inside the housing. A part of the magnetorheological polishing wheel 2 extends out of the housing to facilitate the processing of the workpiece 6. Preferably, the housing can adopt a cube structure, and a part of the magnetorheological polishing wheel 2 extends out from the top of the housing.

[0033] The magnetorheological polishing processing system also has a base 4. The robotic arm 1 can be installed on the base 4. The base 4 is the ground or a metal plate, and the metal plate can be made of cast iron. The workbench 5 can also be installed on the base 4 together with the robotic arm 1 to improve the stability of the system. Of course, the base 4 can also adopt other forms and is not specifically limited.

[0034] Of course, in order to improve the mobility of the device, four universal wheels and a locking device can also be arranged on the base 4 for easy handling and fixing. Those skilled in the art should understand that, of course, the other end of the robotic arm 1 can also be fixedly connected to a carrier such as a mobile platform and is movable relative to the ground. Those skilled in the art should understand that it is not specifically limited.

[0035] The magnetorheological polishing processing system provided by the present invention includes a robotic arm 1, a workpiece fixing device 3 installed at one end of the robotic arm 1, and a workbench having a magnetorheological polishing wheel 2 and a magnetorheological circulation system. The magnetorheological circulation system supplies magnetorheological fluid to the magnetorheological polishing wheel 2. The magnetorheological polishing wheel 2 extends out of the workbench 5. The workpiece fixing device 3 realizes the position change between the magnetorheological polishing wheel 2 under the drive of the robotic arm 1. By utilizing the advantages of the multi-degree-of-freedom, speed, and acceleration of the robotic arm 1 in space, and combining the setting of the magnetorheological polishing wheel on the workbench, the load on the robotic arm can be reduced, making the robotic arm operate more flexibly during processing. Moreover, a magnetorheological polishing wheel with a larger diameter and greater weight can also be used for processing, making the processing efficient and fast, and further improving the overall efficiency of grinding and polishing.

[0036] Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working processes of the systems, devices, and units described above can refer to the corresponding processes in the foregoing method embodiments, and will not be described herein again.

[0037] The above has introduced in detail a magnetorheological polishing processing system provided by the present invention. For those of ordinary skill in the art, according to the idea of the embodiments of the present invention, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation on the present invention.

Claims

1. A magnetorheological finishing processing system, characterized in that, it includes a robotic arm, a workpiece fixing device installed at one end of the robotic arm, and a workbench with a magnetorheological polishing wheel and a magnetorheological circulation system. The magnetorheological circulation system supplies magnetorheological fluid to the magnetorheological polishing wheel. The magnetorheological polishing wheel is fixed to the workbench and realizes controllable liquid-solid phase change polishing through the magnetorheological circulation system. The magnetorheological polishing wheel extends out of the workbench, and the workpiece fixing device realizes position change with the magnetorheological polishing wheel under the drive of the robotic arm; the robotic arm is a robotic arm with six degrees of freedom.

2. The magnetorheological finishing processing system according to claim 1, characterized in that, the workpiece fixing device adopts a vacuum chuck.

3. The magnetorheological finishing processing system according to claim 2, characterized in that, the vacuum chuck includes a chuck, a chuck hoop, a connecting pipe and a vacuum generator. The chuck is communicated with the vacuum generator through the connecting pipe. The chuck hoop is installed at the end of the robotic arm and abuts against the chuck. The vacuum generator is arranged on the robotic arm.

4. The magnetorheological finishing processing system according to claim 1, characterized in that, the magnetorheological circulation system includes a liquid storage tank, a stirrer arranged in the liquid storage tank, a delivery pump, a recovery pump and a circulation supply loop. The circulation supply loop includes a liquid injection pipe and a recovery pipe communicated with the liquid storage tank, a nozzle arranged at the end of the liquid injection pipe and a collector arranged at the end of the recovery pipe. The delivery pump is arranged on the liquid injection pipe, the recovery pump is arranged on the recovery pipe, and the nozzle and the collector are respectively symmetrically arranged on the robotic arm on both sides of the magnetorheological polishing wheel.

5. The magnetorheological finishing processing system according to claim 4, characterized in that, the nozzle is aligned with the edge of the magnetorheological polishing wheel.

6. The magnetorheological finishing processing system according to claim 5, characterized in that, the nozzle is aligned with the tangential direction of the magnetorheological polishing wheel.

7. The magnetorheological finishing processing system according to claim 4, characterized in that, there is a fit or a gap between the collector and the magnetorheological polishing wheel.

8. The magnetorheological finishing processing system according to claim 1, characterized in that, the telescopic direction of the robotic arm is parallel to the plane where the magnetorheological polishing wheel is located.

9. The magnetorheological finishing processing system according to claim 4, characterized in that, the magnetorheological circulation system further includes a pressure and flow rate measuring device, and the pressure and flow rate measuring device is communicated with the liquid injection pipe.

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