Polishing method

Abstract

The application discloses a polishing method. The polishing method comprises the following steps: S1, driving a polishing head to rotate and enabling sandpaper to abut and polish a plurality of corners on a workpiece in sequence, the sandpaper moving along the trend of the corners to complete polishing of each corner; S2, abutting a transition part on the workpiece on one of two oppositely arranged polishing wheels, and driving the workpiece to reciprocate relative to the polishing wheels to polish the transition part on the workpiece by the polishing wheels; S3, first extending a straight edge part between the two polishing wheels, and driving the workpiece to reciprocate relative to the two polishing wheels to enable the straight edge part to contact the polishing wheels to be polished, then extending a curved edge part between the two polishing wheels to polish by the two polishing wheels; and S4, abutting an end part, away from the straight edge part, of the curved edge part on one of the polishing wheels, and then swinging the workpiece with the end part as the center to enable the polishing wheel to polish the end part. The polishing method can improve the machining precision and machining efficiency of the workpiece.

Description

Technical Field

[0001] This application relates to the field of workpiece grinding technology, specifically to a grinding method. Background Technology

[0002] After injection molding, the product needs to be sanded to remove the parting lines. In current practices, operators usually manually sand the parting lines off with sandpaper. However, different operators performing the same operation often produce different results, indicating that the operator's experience has a significant impact on the product yield. Summary of the Invention

[0003] In view of the above, it is necessary to propose a grinding method to reduce the impact of manual operation on the processing progress and improve the grinding accuracy of the workpiece.

[0004] This application provides a grinding method for grinding a workpiece having multiple surrounding sidewalls. Each sidewall has a straight edge, a curved edge, and a transition portion. The transition portion connects the straight edge and the curved edge. The ends of the curved edges on the multiple sidewalls away from the straight edges are connected to form an end. Two connected sidewalls form a corner. The grinding method includes:

[0005] S1. A grinding head with sandpaper is installed on a CNC machine tool. The CNC machine tool drives the grinding head to rotate and causes the sandpaper to sequentially abut against and grind multiple corners on the workpiece. The sandpaper moves along the direction of the corners to complete the grinding of each corner.

[0006] S2. The transition portion on the workpiece is brought into contact with one of two opposing polishing wheels, and the workpiece is driven to reciprocate relative to the polishing wheel so as to polish the transition portion of the workpiece using the polishing wheel.

[0007] S3. First, the straight edge is inserted between the two polishing wheels, and the workpiece is driven to reciprocate relative to the two polishing wheels so that the straight edge contacts the polishing wheels, so that the two polishing wheels can polish the straight edge of the workpiece simultaneously. Then, the curved edge is inserted between the two polishing wheels, and the workpiece is driven to reciprocate relative to the two polishing wheels so that the curved edge contacts the polishing wheels, so that the two polishing wheels can polish it.

[0008] S4. The end of the curved portion that is away from the straight portion is brought into contact with one of two opposing polishing wheels, and then the workpiece is swung around the end as the center, so that the polishing wheel polishes the end.

[0009] In traditional manual operation, the varying experience of different operators significantly impacts workpiece machining accuracy due to human factors. Excessive force can lead to over-grinding, resulting in issues like edge collapse and surface distortion. By employing the aforementioned grinding method, a CNC machine tool drives sandpaper close to and grinds the workpiece. Since manual operation is unnecessary, machining errors caused by human experience are avoided, thus improving both machining accuracy and efficiency.

[0010] In some embodiments, the grinding head includes a flexible body made by a foaming process.

[0011] In some embodiments, the grinding head further includes a magic felt, which is wrapped and fixed on the flexible body, the sandpaper is adhered to the magic felt, and the flexible body is mounted on the CNC machine tool.

[0012] In some embodiments, a feed mechanism is used to adjust the distance between the two polishing wheels so that the two polishing wheels are close to each other and always in contact with the workpiece, in order to compensate for the processing errors caused by the wear of the polishing wheels.

[0013] In some embodiments, a controller controls a robotic arm to hold the workpiece, first bringing the transition portion abutting against the polishing wheel so that the polishing wheel polishes the transition portion. Then, the straight edge portion is driven to extend between the two polishing wheels to polish the straight edge portion. Next, the controller controls the robotic arm to hold the workpiece, causing the curved edge portion to move relative to the two polishing wheels to polish the curved edge portion. Finally, the controller controls the robotic arm to bring the end portion abutting against the polishing wheel to polish the end portion. The controller counts once after each workpiece is processed. When the controller's count reaches a preset value, the controller controls the feed mechanism to drive the two polishing wheels closer to each other.

[0014] In some embodiments, the preset value is 5. When the count of the controller reaches the preset value, the controller controls the feeding mechanism to drive the two polishing wheels to move closer to each other by 0.01 mm.

[0015] In some embodiments, the two polishing wheels have different diameters, with the polishing wheel with a larger diameter being the first polishing wheel and the polishing wheel with a smaller diameter being the second polishing wheel. The first polishing wheel is used to polish the arc surface at the transition portion where the radius of curvature is greater than the radius of the first polishing wheel, and then the second polishing wheel is used to polish the arc surface at the transition portion where the radius of curvature is greater than the radius of the second polishing wheel and less than the radius of the first polishing wheel.

[0016] In some embodiments, the velocity direction of the point on the first polishing wheel that is tangent to the workpiece is the same as the motion direction of the workpiece as it moves between the two polishing wheels; the velocity direction of the point on the second polishing wheel that is tangent to the workpiece is the same as the motion direction of the workpiece as it moves between the two polishing wheels.

[0017] In some embodiments, the polishing method further includes: S5, cleaning the polished workpiece.

[0018] In some embodiments, the workpiece is immersed in a cleaning solution for 4 to 5 minutes, while the temperature of the cleaning solution is maintained between 45 and 65 degrees Celsius. Then, the workpiece is immersed in clean water and cleaned using ultrasonic waves. Finally, the workpiece is rinsed in clean water again. Attached Figure Description

[0019] Figure 1 This is a three-dimensional structural diagram of the workpiece of this application.

[0020] Figure 2 This is a three-dimensional structural diagram of a grinding head provided in some embodiments of this application.

[0021] Figure 3 yes Figure 2 The diagram shown is an exploded view of the grinding head.

[0022] Figure 4 This is a three-dimensional structural schematic diagram of the polishing apparatus provided in some embodiments of this application.

[0023] Figure 5 yes Figure 4 The diagram shows a three-dimensional structure of a portion of the polishing device.

[0024] Figure 6 This is a flowchart of the polishing method described in this application.

[0025] Explanation of main component symbols

[0026] 10 grinding heads

[0027] Flexible body 11

[0028] Magic Felt 12

[0029] Clamping handle 13

[0030] Sandpaper 14

[0031] Polishing device 20

[0032] Feed mechanism 21

[0033] Base 211

[0034] Servo motor 212

[0035] Carriage 213

[0036] Transmission assembly 214

[0037] Guide rail 2141

[0038] 2142 Two-way lead screw

[0039] Polishing wheel 22

[0040] First polishing wheel 221

[0041] Second polishing wheel 222

[0042] Drive component 23

[0043] robotic arm 30

[0044] Controller 40

[0045] Workpiece 200

[0046] Sidewall 201

[0047] Corner 202

[0048] Straight edge 203

[0049] Curved edge 204

[0050] Transition Section 205

[0051] End 206 Detailed Implementation

[0052] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0053] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, it should be noted that "multiple" means two or more, unless otherwise explicitly specified.

[0054] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0055] The following will describe some embodiments of this application in detail with reference to the accompanying drawings.

[0056] This embodiment discloses a grinding method. The workpiece to which this grinding method is applied has the following characteristics: the workpiece has a rod-shaped structure, and the workpiece is composed of a straight-edge structure and an arc-shaped structure. The workpiece is as follows: Figure 1 As shown, taking the temple of an eyeglass as an example, the workpiece 200 is composed of multiple surrounding sidewalls 201. Two interconnected sidewalls 201 form a corner 202. Specifically, there are four corners 202 on the workpiece 200, and each corner 202 will have a residual parting line after injection molding. Each sidewall includes a straight edge 203, a curved edge 204, and a transition part 205. The transition part 205 connects the straight edge 203 and the curved edge 204. For easy distinction, Figure 1 Two solid lines are added to distinguish the straight edge 203, the curved edge 204, and the transition 205; however, these two lines do not exist on the actual workpiece 200. The ends of the four curved edges 204 that are furthest from the straight edge 203 are connected together to form the end 206.

[0057] The polishing method disclosed in this embodiment uses two polishing tools, as described in detail below.

[0058] Please see Figure 2 and Figure 3 The grinding head 10 consists of a flexible body 11, a magic felt 12, a clamping handle 13, and sandpaper 14. The flexible body 11 is made of polyurethane. The flexible body 11 is cylindrical, and the clamping handle 13 is located at the center of the flexible body 11, serving as a support. The flexible body 11 can be mounted on a CNC machine tool via the clamping handle 13. The magic felt 12 is located around the circumference of the flexible body 11 and is used to fix the sandpaper 14. The back of the sandpaper 14 has a nap. When installing the sandpaper 14, the operator only needs to align the nap with the magic felt 12 and then let the sandpaper 14 adhere to the magic felt 12 to fix the sandpaper 14 to the flexible body 11. The sandpaper 14 is used to grind the workpiece 200.

[0059] Sandpaper 14 is a consumable material that needs to be discarded after a certain period of use. Since sandpaper 14 is adhered to the flexible body 11 via magic felt 12, when replacing sandpaper 14, the operator only needs to tear it off the flexible body 11. During the replacement process, the operator simply tears off the old sandpaper 14 and attaches the new one, making sandpaper 14 replacement simple and quick. By using this grinding head 10 in assembly line production, sandpaper 14 can be replaced quickly, thereby improving the processing efficiency of workpiece 200.

[0060] Furthermore, since the flexible body 11 is made of polyurethane, it is relatively soft and has a certain degree of elasticity. When the sandpaper 14 comes into contact with the workpiece 200, the flexible body 11 will deform to a certain extent, allowing it to better conform to the surface of the workpiece 200. Because of the better fit between the flexible body 11 and the workpiece 200, the sandpaper 14 can fully contact the surface of the workpiece 200, thus thoroughly polishing the workpiece 200 and avoiding any missed areas. The aforementioned polishing head 10 is suitable for polishing workpieces 200 with curved surfaces. By utilizing the characteristics of the flexible body 11, the sandpaper 14 can polish curved surfaces without any blind spots.

[0061] Please see Figure 4 and Figure 5 A polishing apparatus 20 is used to polish a ground workpiece 200 to reduce the surface roughness of the workpiece 200. The polishing apparatus 20 includes a feeding mechanism 21, two polishing wheels 22, and driving members 23 respectively connected to the two polishing wheels 22. The feeding mechanism 21 can drive the two polishing wheels 22 to move closer together, and the two polishing wheels 22 rotate under the drive of the corresponding driving members 23 to polish the workpiece 200. The driving member 23 is a motor, and the polishing wheels 22 are cloth wheels.

[0062] Please see Figure 4 and Figure 5 In some embodiments, the feed mechanism 21 includes a base 211, a servo motor 212, two carriages 213, and a transmission assembly 214. The transmission assembly 214 is mounted on the base 211 and connected to the servo motor 212. Each carriage 213 is slidably mounted on the base 211, and the transmission assembly 214 is connected to both carriages 213. Two drive members 23 correspond one-to-one with the two carriages 213 and are mounted on the corresponding carriages 213. Two polishing wheels 22 correspond one-to-one with the two carriages 213 and are rotatably mounted on the corresponding carriages 213.

[0063] When the workpiece 200 needs to be polished, the two drive components 23 drive the corresponding polishing wheel 22 to rotate. After the polishing wheel 22 has been used for a period of time, the polishing wheel 22 will wear and the diameter of the polishing wheel 22 will shrink. At this time, the servo motor 212 rotates and the transmission component 214 transmits power to the two slides 213. The two slides 213 move relative to each other, thereby reducing the distance between the two polishing wheels 22, so that the two polishing wheels 22 can always be in contact with the workpiece 200 to meet the requirements of polishing the workpiece 200.

[0064] Please see Figure 4 and Figure 5 In some embodiments, the polishing apparatus 20 further includes a robotic arm 30 and a controller 40. The robotic arm 30 is disposed on one side of the polishing wheels 22 and is used to grip the workpiece 200 and place it between the two polishing wheels 22 for polishing. Both the robotic arm 30 and the servo motor 212 are electrically connected to the controller 40. The controller 40 is used to control the robotic arm 30 so that it moves according to the program instructions written in the controller 40, and to send instructions to the servo motor 212 to control the servo motor 212 to rotate, thereby driving the transmission assembly 214 to move.

[0065] Please see Figure 4 and Figure 5 In some embodiments, the transmission assembly 214 includes a guide rail 2141 and a bidirectional lead screw 2142. The bidirectional lead screw 2142 is connected to a servo motor 212 and is used to rotate under the drive of the servo motor 212. The bidirectional lead screw 2142 has both left-hand and right-hand threads. There are two guide rails 2141, which are mounted on the base 211 and are located on both sides of the bidirectional lead screw 2142. The bidirectional lead screw 2142 is rotatably connected to two carriages 213, and the two carriages 213 are slidably connected to the guide rails 2141.

[0066] The transmission assembly 214 is implemented as follows: the servo motor 212 drives the bidirectional lead screw 2142 to rotate. At this time, the bidirectional lead screw 2142 and the slide 213 rotate relative to each other. Since both slides 213 are slidably connected to the guide rail 2141, the two slides 213 slide relative to each other along the guide rail 2141 under the drive of the bidirectional lead screw 2142, thereby achieving the purpose of getting closer to each other, and thus compensating for the error caused by the wear of the polishing wheel 22.

[0067] Please see Figure 1 , Figure 5 and Figure 6 This application discloses a polishing method that utilizes the aforementioned polishing head 10 and polishing device 20.

[0068] When grinding workpiece 200, the parting line needs to be removed first, and then the straight edge 203, curved edge 204, and transition part 205 need to be polished. Specific methods include:

[0069] S1. The grinding head 10 with sandpaper 14 is installed on the CNC machine tool. The CNC machine tool drives the grinding head 10 to rotate and causes the sandpaper 14 to successively abut against and grind multiple corners 202 on the workpiece 200. The sandpaper 14 moves along the trend of the corners 202 to complete the grinding of each corner 202.

[0070] S2. The transition portion 205 on the workpiece 200 is brought into contact with one of the two opposing polishing wheels 22, and the workpiece 200 is driven to reciprocate relative to the polishing wheel 22 so as to polish the transition portion 205 of the workpiece 200 using the polishing wheel 22.

[0071] In this embodiment, the workpiece 200 is inserted into the robot arm 30, and the controller 40 controls the robot arm 30 to move so that the transition part 205 on the workpiece 200 abuts against the rotating polishing wheel 22. Then the robot arm 30 drives the workpiece 200 to make linear reciprocating motion along the Y-axis direction. Then the workpiece 200 is rotated to polish other parts on the transition part 205 so that the transition part 205 has no dead corners.

[0072] S3. First, the straight edge 203 is inserted between the two polishing wheels 22, and the workpiece 200 is driven to reciprocate relative to the two polishing wheels 22 so that the straight edge 203 contacts the polishing wheels 22, so that the two polishing wheels 22 can polish the straight edge 203 of the workpiece 200 simultaneously. Then, the curved edge 204 is inserted between the two polishing wheels 22, and the workpiece 200 is driven to reciprocate relative to the two polishing wheels 22 so that the curved edge 204 contacts the polishing wheels 22, so that the two polishing wheels 22 can polish.

[0073] In this embodiment, the controller 40 first controls the robot arm 30 to adjust the posture of the workpiece 200 so that the workpiece 200 is set along the Z-axis; then the robot arm 30 is driven to insert the workpiece 200 between the two polishing wheels 22; next, the robot arm 30 drives the workpiece 200 to make linear reciprocating motion along the Y-axis, and at the same time the robot arm 30 drives the workpiece 200 to make reciprocating motion along the Z-axis, so that the two polishing wheels 22 can polish all parts on the straight edge 203; finally, the robot arm 30 drives the workpiece 200 to rotate so that the two polishing wheels 22 can polish all the straight edges 203 on the sidewalls 201.

[0074] After the straight edge 203 is polished, the robot arm 30 adjusts the angle of the workpiece 200 so that the curved edge 204 can be inserted between the two polishing wheels 22. Then the robot arm 30 drives the workpiece to reciprocate along the Y-axis. At the same time, the robot arm 30 drives the workpiece 200 to slowly move along the positive Z-axis. Then the robot arm 30 drives the workpiece 200 to rotate. Under the drive of the robot arm 30, the polishing wheels 22 realize the polishing operation on the curved edge 204 of the workpiece 200.

[0075] S4. Place the end 206 against one of the two opposing polishing wheels 22, and then swing the workpiece 200 around the end 206 to polish the end 206.

[0076] In this embodiment, after the polishing wheel 22 completes the polishing operation on the curved edge 204, the robot arm 30 drives the workpiece 200 to disengage from the two polishing wheels 22; then the robot arm 30 abuts the end 206 against the polishing wheel 22 and simultaneously drives the workpiece 200 to reciprocate along the Y-axis; then, with the end 206 as the center, the workpiece 200 is swung at a certain angle in the positive X-axis direction. At this time, the robot arm 30 continues to drive the workpiece 200 to reciprocate along the Y-axis. After that, the robot arm 30 drives the workpiece 200 to swung at a certain angle in the negative X-axis direction, the positive Y-axis direction, and the negative Y-axis direction in sequence, so that the polishing wheel 22 can polish all parts on the end 206.

[0077] In traditional processing methods, operators first manually remove the parting lines on workpiece 200 using sandpaper 14, and then hold workpiece 200 close to polishing wheel 22 so that polishing wheel 22 polishes workpiece 200. During the processing of workpiece 200, the processing accuracy of workpiece 200 depends entirely on the operator's experience, resulting in an unstable processing yield of workpiece 200.

[0078] The manual processing method has the following problems: Due to differences in the force applied by different operators when holding the workpiece 200, when the contact force between the workpiece 200 and the polishing wheel 22 is too great, although the polishing wheel 22 can remove the parting line on the workpiece 200, it will also grind the surface of the workpiece 200, causing a change in the curvature of the curved surface and resulting in surface distortion. Alternatively, excessive contact force between the workpiece 200 and the polishing wheel 22 can cause a large slope at the corners of the workpiece 200, leading to edge collapse. Furthermore, because the workpiece 200 has curved edges 204, some areas may be missed during polishing, resulting in dead corners that cannot be polished. Since the workpiece 200 is polished manually, it requires a large workforce, resulting in high labor intensity for the operators, and the processing efficiency of the workpiece 200 is also low.

[0079] Therefore, since both the grinding and polishing of workpiece 200 in this embodiment are performed by mechanical equipment, the processing method of workpiece 200 in this embodiment does not require manual operation by operators, thus reducing manpower input and labor intensity. Furthermore, polishing processes generate noise and dust, which can harm the health of operators who work in this environment for extended periods due to inhalation of dust and noise. Because the grinding and polishing of workpiece 200 is automated, operators do not need to approach workpiece 200 during the grinding or polishing process. Therefore, the dust generated during grinding is less likely to be inhaled, and operators are also protected from noise interference.

[0080] When workpiece 200 contacts polishing wheel 22, polishing wheel 22 exerts a force on workpiece 200, which pushes workpiece 200 away from polishing wheel 22. When polishing workpiece 200 with one polishing wheel 22, the force will cause workpiece 200 to vibrate, thus affecting the polishing process. When polishing workpiece 200 with two polishing wheels 22 simultaneously, the forces generated by the two polishing wheels 22 will cancel each other out, preventing workpiece 200 from vibrating during polishing and improving its stability. Because vibration of workpiece 200 is avoided, the machining accuracy of workpiece 200 is also improved.

[0081] Please see Figure 1 , Figure 2 and Figure 3 In some embodiments, the grinding head 10 includes a flexible body 11, which is made by a foaming process.

[0082] In this embodiment, the flexible body 11 installed on the CNC machine tool is a foam head made of polyurethane material through a foaming process. Since the flexible body 11 is made of polyurethane foam, it is relatively soft and has a certain degree of elasticity. When the sandpaper 14 comes into contact with the workpiece 200, the flexible body 11 will undergo a certain deformation, allowing it to better conform to the curved edge 204 of the workpiece 200. Due to the better fit between the flexible body 11 and the workpiece 200, the sandpaper 14 can fully contact the curved edge 204, achieving thorough removal of the parting line on the workpiece 200 when the sandpaper 14 polishes along the surface of the workpiece 200.

[0083] In some embodiments, the grinding head 10 also includes a magic felt 12, which is wrapped and fixed on the flexible body 11, and sandpaper 14 is adhered to the magic felt 12. The flexible body 11 is mounted on a CNC machine tool.

[0084] Thus, when the flexible body 11 rotates, the sandpaper 14 rotates along with it, allowing the sandpaper 14 to continuously polish the surface of the workpiece 200 to remove parting lines. Furthermore, because the flexible body 11 is relatively soft, it will deform after a period of use, requiring replacement to ensure the precision of polishing the workpiece 200. When replacing the flexible body 11, the magic felt 12 can be recycled for future reuse.

[0085] Please see Figure 1 and Figure 4 In some embodiments, a feed mechanism 21 is used to adjust the distance between the two polishing wheels 22 so that the two polishing wheels 22 are close to each other and always in contact with the workpiece 200, in order to compensate for the processing error caused by the wear of the polishing wheels 22.

[0086] During the polishing process of polishing the workpiece 200, the polishing wheel 22 will wear down, resulting in a reduction in the diameter of the polishing wheel 22. When the wear of the polishing wheel 22 reaches a certain level, the polishing wheel 22 can no longer effectively polish the workpiece 200. At this time, it is necessary to move the position of the two polishing wheels 22. Thus, by adjusting the distance between the two polishing wheels 22 using the feed mechanism 21, the two polishing wheels 22 are brought closer to each other, so that the two polishing wheels 22 can simultaneously abut against the workpiece 200 to complete the polishing of the straight edge 203 of the workpiece 200. Therefore, the operation of the feed mechanism 21 to adjust the polishing wheels 22 plays a role in compensating for errors.

[0087] Please see Figure 1 and Figure 4In some embodiments, the controller 40 controls the robot arm 30 to hold the workpiece 200 and first bring the transition portion 205 abutting against the polishing wheel 22 so that the polishing wheel 22 polishes the transition portion 205. Then, the straight edge portion 203 is driven to extend between the two polishing wheels 22 to polish the straight edge portion 203. Next, the controller controls the robot arm 30 to hold the workpiece 200 so that the curved edge portion 204 moves relative to the two polishing wheels 22 to polish the curved edge portion 204. Finally, the controller 40 controls the robot arm 30 to bring the end portion 206 abutting against the polishing wheel 22 to polish the end portion 206. The controller 40 counts once each workpiece 200 is processed. When the count of the controller 40 reaches a preset value, the controller 40 controls the feed mechanism 21 to drive the two polishing wheels 22 to move closer to each other.

[0088] Under the control of the controller 40, the robot arm 30 first drives the workpiece 200 to move downward from above the two polishing wheels 22, and extends the workpiece 200 between the two polishing wheels 22 so that the two polishing wheels 22 polish the straight edge 203 of the workpiece 200; after the polishing wheels 22 have completed the polishing operation on the straight edge 203, the robot arm 30 drives the curved edge 204 on the workpiece 200 to abut against the polishing wheel 22, and then the robot arm 30 drives the workpiece 200 to move relative to the polishing wheel 22 so that the polishing wheel 22 polishes the curved edge 204; then, the robot arm 30 abuts the end 206 of the workpiece 200 against the polishing wheel 22 so that the polishing wheel 22 polishes the end 206 of the workpiece 200. After the controller 40 controls the robotic arm 30 to drive the workpiece 200 to complete the polishing operation, the controller 40 will perform a count. Each count by the controller 40 represents the completion of processing one workpiece 200. The larger the count, the more workpieces 200 have been processed, and the greater the wear of the polishing wheel 22. When the count value reaches the preset value in the controller 40, the controller 40 controls the feeding mechanism 21 to move the two polishing wheels 22, thereby compensating for errors. Under the control of the controller 40, not only is the automatic processing of workpieces 200 realized, but the number of workpieces 200 processed can also be recorded in real time. Because the controller 40 can record the number of workpieces 200 in real time, it can control the feeding mechanism 21 to adjust the distance between the two polishing wheels 22 in a timely manner, thereby compensating for processing errors caused by the wear of the polishing wheels 22.

[0089] Please see Figure 1 and Figure 4 In some implementations, the preset value of the controller 40 is 5. When the count of the controller 40 reaches the preset value, the controller 40 controls the feeding mechanism 21 to drive the two polishing wheels 22 to move closer to each other by 0.01mm.

[0090] Setting the preset value to 5 means that after polishing wheel 22 completes polishing operations on 5 workpieces 200, controller 40 controls servo motor 212 to rotate. Servo motor 212 then drives bidirectional lead screw 2142 to rotate. At this time, bidirectional lead screw 2142 drives two carriages 213 to slide relative to each other, thus bringing the two polishing wheels 22 closer together. A larger preset value indicates that the polishing wheel 22 polishes more workpieces 200, resulting in more severe wear on the polishing wheel 22. Furthermore, a larger preset value also indicates a longer adjustment time for the polishing wheel 22 spacing. Because the adjustment time is longer, using a severely worn polishing wheel 22 to polish workpieces 200 will result in workpieces 200 that do not meet the required machining accuracy. Since the feed mechanism 21 adjusts the polishing wheel 22 spacing after processing 5 workpieces 200, it can compensate for errors, thus ensuring consistent machining accuracy for the workpieces 200.

[0091] Please see Figure 1 and Figure 4 In some embodiments, the two polishing wheels 22 have different diameters. The polishing wheel 22 with a larger diameter is the first polishing wheel 221, and the polishing wheel 22 with a smaller diameter is the second polishing wheel 222. The first polishing wheel 221 is used to polish the arc surface at the transition portion 205 where the radius of curvature is greater than that of the first polishing wheel 221. Then, the second polishing wheel 222 is used to polish the arc surface at the transition portion 205 where the radius of curvature is greater than that of the second polishing wheel 222 and smaller than that of the first polishing wheel 221.

[0092] In this embodiment, the polishing of the transition portion 205 by the two polishing wheels 22 can be divided into two steps:

[0093] The first step is implemented as follows: Under the control of the controller 40, the robot arm 30 first makes the transition part 205 of the workpiece 200 abut against the first polishing wheel 221, and then drives the workpiece 200 to reciprocate along the Y-axis so that the first polishing wheel 221 polishes the arc surface with a radius of curvature greater than the radius of the first polishing wheel 221. Then the robot arm 30 drives the transition part 205 to abut against the second polishing wheel 222 and drives the workpiece 200 to reciprocate along the Y-axis. Then the robot arm 30 drives the workpiece 200 to swing from the positive X-axis to the negative X-axis with the Y-axis as the axis so that the second polishing wheel 222 polishes the arc surface at the transition part 205 with a radius of curvature greater than the radius of the second polishing wheel 222 and smaller than the radius of the first polishing wheel 221.

[0094] The second step involves readjusting the orientation of the workpiece 200 so that the wider sidewall 201 faces the Z-axis. The robot arm 30 first places the workpiece 200 between the two polishing wheels 22 for polishing, during which the workpiece 200 reciprocates along the Y-axis. Then, the robot arm 30 rotates the workpiece 200 180 degrees and performs the same polishing action again. Since the two polishing wheels 22 are cloth wheels, when the transition part 205 is placed between the two polishing wheels 22, the two polishing wheels 22 can cover the transition part 205, so that the unpolished parts of the transition part 205 can be polished.

[0095] Thus, when the transition section 205 contacts the first polishing wheel 221, the larger contact area between the first polishing wheel 221 and the transition section 205 allows for efficient polishing by first polishing the transition section 205. After the first polishing wheel 221 completes its polishing, the second polishing wheel 222 is used to polish areas that the larger polishing wheel 22 cannot reach, thereby completing the polishing operation of the entire transition section 205. Compared to polishing the transition section 205 using only the second polishing wheel 222, using a large and a small polishing wheel 22 not only improves polishing efficiency but also ensures the polishing precision of the transition section 205, avoiding any missed areas.

[0096] Please see Figure 1 and Figure 4 In some embodiments, the velocity direction of the point where the first polishing wheel 221 is tangent to the workpiece 200 is the same as the motion direction of the workpiece 200 as it enters the space between the two polishing wheels 22; the velocity direction of the point where the second polishing wheel 222 is tangent to the workpiece 200 is the same as the motion direction of the workpiece 200 as it enters the space between the two polishing wheels 22. Figure 4 From the perspective of the center, the first polishing wheel 221 should rotate counterclockwise and the second polishing wheel 222 should rotate clockwise.

[0097] Driven by the robot arm 30, the workpiece 200 moves downward from above the polishing wheel 22 to insert the straight edge 203 between the two polishing wheels 22. At this time, when both the first polishing wheel 221 and the second polishing wheel 222 are in contact with the workpiece 200, the two polishing wheels 22 exert a force on the workpiece 200 in the downward direction. This creates a tendency for the two polishing wheels 22 to pull the workpiece 200 downward, making it easier for the workpiece 200 to be inserted between the two polishing wheels 22. When the velocity direction of the point where the first polishing wheel 221 is tangent to the workpiece 200 is opposite to the direction of movement of the workpiece 200, and the velocity direction of the point where the second polishing wheel 222 is tangent to the workpiece 200 is also opposite to the direction of movement of the workpiece 200, the force exerted by the two polishing wheels 22 on the workpiece 200 is upward. This creates a tendency for the two polishing wheels 22 to hinder the downward movement of the workpiece 200, making it difficult for the workpiece 200 to be inserted between the two polishing wheels 22, thus affecting the polishing operation of the workpiece 200.

[0098] The polishing method provided in this embodiment may further include: S5, cleaning the polished workpiece 200 to remove dust and wax residue. During the polishing process, wax is typically applied to the polishing wheel 22 after polishing every five workpieces 200. The polishing wax serves to abrade and lubricate, enhancing the abrasive action of the polishing wheel 22 and resulting in a better polishing effect for the workpiece 200. After polishing, the surface of the workpiece 200 will retain abrasive powder and wax residue, which can be removed by cleaning the workpiece 200.

[0099] Please see Figure 1 In some embodiments, the workpiece 200 is immersed in a cleaning solution for 4 to 5 minutes, while the temperature of the cleaning solution is maintained between 45 and 65 degrees Celsius. Then, the workpiece 200 is immersed in clean water and cleaned using ultrasonic waves. Finally, the workpiece 200 is rinsed in clean water again.

[0100] In this embodiment, the cleaning device for cleaning workpiece 200 has four sequentially arranged grooves, each groove equipped with a hook. The first groove contains cleaning fluid, and the second to fourth grooves contain clean water. When cleaning workpiece 200, the soaking time and temperature of the cleaning fluid can be determined based on the concentration of the cleaning fluid to achieve better cleaning results. Specifically, the soaking time of workpiece 200 is selected between 4 minutes and 30 seconds and 5 minutes and 30 seconds, and the temperature of the cleaning fluid is selected between 45 degrees Celsius and 65 degrees Celsius. The selected soaking time and temperature ranges include the two endpoints of the aforementioned time and temperature ranges. Then, the four hooks operate simultaneously to place workpiece 200 from the first groove into the second groove, from the second groove into the third groove, from the third groove into the fourth groove, and from the fourth groove into a carrier for loading workpiece 200. At this time, an ultrasonic device emits ultrasonic waves to the workpiece 200 in the second groove to clean it. After being cleaned, the workpiece 200 will be placed in an oven to dry.

[0101] The cleaning solution can dissolve wax blocks. When the workpiece 200 is placed in the cleaning solution, the residual wax blocks on the workpiece 200 can be removed. As the operator uses ultrasonic waves to clean the workpiece 200, the ultrasonic waves cause the dirt on the workpiece 200 to peel off from the workpiece 200 to achieve the purpose of further cleaning.

[0102] The working process of the polishing method provided in some embodiments is roughly as follows:

[0103] First, the grinding head 10 is installed on the CNC machine tool. The CNC machine tool drives the flexible body 11 to rotate, thereby rotating the sandpaper 14. Simultaneously, the sandpaper 14 is driven to approach the four corners 202 on the workpiece 200 in sequence. When the sandpaper 14 contacts the parting line on the corner 202, the CNC machine tool drives the sandpaper 14 to move along the corner 202 from one end of the workpiece 200 to the other end to grind the corner 202. Since the sandpaper 14 has a short service life, it needs to be replaced after each grinding operation of the workpiece 200. At this time, the operator can directly tear the sandpaper 14 off the flexible body 11 and stick the new sandpaper 14 onto the flexible body 11.

[0104] Then, under the control of the controller 40, the robot arm 30 first makes the transition part 205 of the workpiece 200 abut against the first polishing wheel 221, and then drives the workpiece 200 to reciprocate along the Y-axis, so that the first polishing wheel 221 polishes the arc surface with a radius of curvature greater than the radius of the first polishing wheel 221. Then the robot arm 30 drives the transition part 205 to abut against the second polishing wheel 222, and drives the workpiece 200 to reciprocate along the Y-axis. Then the robot arm 30 drives the workpiece 200 to swing from the positive X-axis to the negative X-axis with the Y-axis as the axis, so that the second polishing wheel 222 polishes the arc surface at the transition part 205 with a radius of curvature greater than the radius of the second polishing wheel 222 and smaller than the radius of the first polishing wheel 221.

[0105] Next, the controller 40 first controls the robot arm 30 to adjust the posture of the workpiece 200 so that the workpiece 200 is set along the Z-axis; then the robot arm 30 is driven to insert the workpiece 200 between the two polishing wheels 22; then the robot arm 30 drives the workpiece 200 to make linear reciprocating motion along the Y-axis, and at the same time the robot arm 30 drives the workpiece 200 to make reciprocating motion along the Z-axis, so that the two polishing wheels 22 can polish all parts on the straight edge 203; finally the robot arm 30 drives the workpiece 200 to rotate so that the two polishing wheels 22 can polish all the straight edges 203 on the sidewalls 201.

[0106] After the straight edge 203 is polished, the robot arm 30 adjusts the angle of the workpiece 200 so that the curved edge 204 can be inserted between the two polishing wheels 22. Then the robot arm 30 drives the workpiece to reciprocate along the Y-axis. At the same time, the robot arm 30 drives the workpiece 200 to slowly move along the positive Z-axis. Then the robot arm 30 drives the workpiece 200 to rotate. Under the drive of the robot arm 30, the polishing wheels 22 realize the polishing operation on the curved edge 204 of the workpiece 200.

[0107] Next, after the polishing wheel 22 completes the polishing operation on the curved edge 204, the robot arm 30 drives the workpiece 200 to disengage from the two polishing wheels 22; then the robot arm 30 abuts the end 206 against the polishing wheel 22 and simultaneously drives the workpiece 200 to reciprocate along the Y-axis; then, with the end 206 as the center, the workpiece 200 is swung at a certain angle in the positive X-axis direction. At this time, the robot arm 30 continues to drive the workpiece 200 to reciprocate along the Y-axis. After that, the robot arm 30 drives the workpiece 200 to swung at a certain angle in the negative X-axis direction, the positive Y-axis direction, and the negative Y-axis direction in sequence, so that the polishing wheel 22 can polish all parts on the end 206.

[0108] Finally, when cleaning workpiece 200, it is first soaked for 4 minutes and 30 seconds to 5 minutes and 30 seconds. Then, all four hooks operate simultaneously to transfer workpiece 200 from the first groove to the second groove, from the second groove to the third groove, from the third groove to the fourth groove, and finally to the carrier for loading workpiece 200. At this point, ultrasonic waves are emitted towards workpiece 200 in the second groove to clean it. After cleaning, workpiece 200 is placed in an oven to dry.

[0109] The grinding method provided in this application embodiment is operated by mechanical equipment for both grinding and polishing of the workpiece 200. Therefore, no manual operation by operators is required, which reduces manpower input and labor intensity.

[0110] When workpiece 200 contacts polishing wheel 22, polishing wheel 22 exerts a force on workpiece 200, which pushes workpiece 200 away from polishing wheel 22. When polishing workpiece 200 with one polishing wheel 22, the force will cause workpiece 200 to vibrate, thus affecting the polishing process. When polishing workpiece 200 with two polishing wheels 22 simultaneously, the forces generated by the two polishing wheels 22 will cancel each other out, preventing workpiece 200 from vibrating during polishing and improving its stability. Because vibration of workpiece 200 is avoided, the machining accuracy of workpiece 200 is also improved.

[0111] In addition, the controller 40 records the number of processed workpieces 200 in real time, so that the controller 40 can control the feed mechanism 21 to adjust the distance between the two polishing wheels 22 in a timely manner, thereby compensating for the processing error caused by the wear of the polishing wheels 22.

[0112] It will be apparent to those skilled in the art that this application is not limited to the details of the exemplary embodiments described above, and that this application can be implemented in other specific forms without departing from the spirit or essential characteristics of this application. Therefore, the embodiments should be regarded as exemplary and non-limiting in all respects, and the scope of this application is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be embraced within this application.

[0113] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit it. Although this application has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this application without departing from the spirit and scope of the technical solutions of this application.

Claims

1. A grinding method for grinding a workpiece having a plurality of surrounding sidewalls, each sidewall having a straight edge, a curved edge, and a transition portion, the transition portion connecting the straight edge and the curved edge, the ends of the curved edges on the plurality of sidewalls away from the straight edges being connected to form an end, and two connected sidewalls forming a corner, characterized in that, include: S1. A grinding head with sandpaper is installed on a CNC machine tool. The CNC machine tool drives the grinding head to rotate and causes the sandpaper to sequentially abut against and grind multiple corners on the workpiece. The sandpaper moves along the direction of the corners to complete the grinding of each corner. S2. The transition portion on the workpiece is brought into contact with one of two opposing polishing wheels, and the workpiece is driven to reciprocate relative to the polishing wheel so as to polish the transition portion of the workpiece using the polishing wheel. S3. First, the straight edge is inserted between two opposing polishing wheels, and the workpiece is driven to reciprocate relative to the two polishing wheels so that the straight edge contacts the polishing wheels, so that the two polishing wheels can polish the straight edge of the workpiece synchronously. Then, the curved edge is inserted between the two polishing wheels, and the workpiece is driven to reciprocate relative to the two polishing wheels so that the curved edge contacts the polishing wheels, so that the two polishing wheels can polish it. S4. The end of the curved portion that is away from the straight portion is brought into contact with one of two opposing polishing wheels, and then the workpiece is swung around the end as the center, so that the polishing wheel polishes the end. The two polishing wheels have different diameters. The polishing wheel with a larger diameter is the first polishing wheel, and the polishing wheel with a smaller diameter is the second polishing wheel. The first polishing wheel is used to polish the arc surface at the transition section where the radius of curvature is greater than the radius of the first polishing wheel. Then, the second polishing wheel is used to polish the arc surface at the transition section where the radius of curvature is greater than the radius of the second polishing wheel and less than the radius of the first polishing wheel.

2. The polishing method as described in claim 1, characterized in that, The grinding head includes a flexible body, which is made by a foaming process.

3. The polishing method as described in claim 2, characterized in that, The grinding head also includes a magic felt, which is wrapped and fixed to the outer surface of the flexible body. The sandpaper is adhered to the magic felt, and the flexible body is mounted on the CNC machine tool.

4. The polishing method as described in claim 1, characterized in that, A feed mechanism is used to adjust the distance between the two polishing wheels, so that the two polishing wheels are close to each other and always in contact with the workpiece, in order to compensate for the processing error caused by the wear of the polishing wheels.

5. The polishing method as described in claim 4, characterized in that, The controller controls a robotic arm to hold the workpiece, first bringing the transition portion abutting against the polishing wheel so that the polishing wheel polishes the transition portion. Then, the straight edge portion is driven to extend between the two polishing wheels to polish the straight edge portion. Next, the controller controls the robotic arm to hold the workpiece and move the curved edge portion relative to the two polishing wheels to polish the curved edge portion. Finally, the controller controls the robotic arm to bring the end portion abutting against the polishing wheel to polish the end portion. The controller counts once after each workpiece is processed. When the controller's count reaches a preset value, the controller controls the feeding mechanism to drive the two polishing wheels closer to each other.

6. The polishing method as described in claim 5, characterized in that, The preset value is 5. When the controller count reaches the preset value, the controller controls the feeding mechanism to drive the two polishing wheels to move closer to each other by 0.01mm.

7. The polishing method as described in claim 1, characterized in that, The velocity direction of the point on the first polishing wheel that is tangent to the workpiece is the same as the motion direction of the workpiece as it moves between the two polishing wheels; the velocity direction of the point on the second polishing wheel that is tangent to the workpiece is the same as the motion direction of the workpiece as it moves between the two polishing wheels.

8. The polishing method as described in claim 1, characterized in that, The polishing method also includes: S5. Clean the polished workpiece.

9. The polishing method as described in claim 8, characterized in that, The workpiece is immersed in the cleaning solution for 4 to 5 minutes, while the temperature of the cleaning solution is maintained between 45 and 65 degrees Celsius. Then, the workpiece is immersed in clean water and cleaned using ultrasound. Finally, the workpiece is rinsed in clean water again.

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