Grinding belt polishing apparatus and polishing control method

Abstract

The application discloses a grinding abrasive belt polishing device, which comprises a rack, a polishing device, two polishing mechanisms arranged in the up-down direction, each polishing mechanism comprising a torque motor, a force output mechanism, a posture adjusting mechanism and a contact wheel mechanism, the torque motor and the force output mechanism being arranged on the rack, the torque motor being provided with an encoder, the rotating shaft of the torque motor being connected with the posture adjusting mechanism, the force output mechanism comprising a cylinder, a displacement sensor arranged on the cylinder and a force sensor connected with the piston rod of the cylinder, the force sensor being hinged to the posture adjusting mechanism, the posture adjusting mechanism being connected with the contact wheel mechanism, and the posture adjusting mechanism and the contact wheel mechanism being both provided with an abrasive belt therearound; and a driving mechanism for driving the abrasive belt to move. The application further discloses a grinding abrasive belt polishing method. The application can respond in time and quickly under the condition that the grinding force is continuously changed, can effectively control the small grinding amount with large change, and improves the grinding precision.

Description

Technical Field

[0001] This invention belongs to the field of automated grinding technology, specifically relating to a grinding belt polishing device and a polishing control method. Background Technology

[0002] With the continuous advancement of industrial automation, robotic automated devices are increasingly replacing manual grinding in the traditional grinding field. However, the following defects exist in actual grinding processes: 1) Most automated grinding devices do not perform gravity balancing at the contact wheel, causing the cylinder output force to overcome significant gravity while simultaneously outputting appropriate grinding force during the grinding process. Since the cylinder outputs force through gas compression, this results in a certain lag, making it unable to respond promptly and quickly to changes in the grinding control target force; 2) Due to the large amount of grinding generated during belt grinding... 1) Heat is generated during grinding, and the heat dissipation range per unit cross-section of the abrasive belt is relatively small. Therefore, abrasive belts with shorter circumferences often have shorter lifespans. 2) For a single abrasive belt grinding end device, the end contact wheel easily absorbs a large amount of heat during the grinding process, especially for some difficult-to-machine materials, which can easily lead to a shortened lifespan of the contact wheel. 3) For integral workpieces or workpieces with many curvature changes, a single abrasive belt grinding device needs to constantly change the position and posture between the complex workpiece and the contact wheel during the grinding process to adapt to the changes in the convex and concave planes. This not only affects efficiency, but also some postures cannot be achieved by the robot, which can easily affect its machining accuracy. Summary of the Invention

[0003] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a grinding belt polishing device and a polishing control method.

[0004] To achieve the above objectives, an embodiment of the present invention provides the following technical solution:

[0005] A grinding belt polishing device, comprising:

[0006] frame;

[0007] A grinding device includes two grinding mechanisms arranged in a vertical direction. Each grinding mechanism includes a torque motor, a force output mechanism, a posture adjustment mechanism, and a contact wheel mechanism. The torque motor and the force output mechanism are both mounted on the frame. The torque motor is equipped with an encoder. The rotating shaft of the torque motor is connected to the posture adjustment mechanism. The force output mechanism includes a cylinder, a displacement sensor mounted on the cylinder, and a force sensor connected to the piston rod of the cylinder. The force sensor is hinged to the posture adjustment mechanism. The posture adjustment mechanism is connected to the contact wheel mechanism. A sanding belt is wound around both the posture adjustment mechanism and the contact wheel mechanism.

[0008] A drive mechanism is used to drive the sanding belt to move.

[0009] As a further improvement of the present invention, two support plates are arranged opposite each other on one side of the attitude adjustment mechanism in the front-back direction, and the force sensor is at least partially located between the two support plates, and the force sensor is connected to the support plates by a pin.

[0010] As a further improvement of the present invention, the contact wheel mechanism includes a side plate, a contact wheel disposed at one end of the side plate, and two adjusting wheels disposed opposite to each other on the side plate in the vertical direction, and the other end of the side plate is connected to the other side of the attitude adjustment mechanism.

[0011] As a further improvement of the present invention, the attitude adjustment mechanism includes a connecting rod extending in the vertical direction, two first tension wheel assemblies respectively connected to both ends of the connecting rod, the rotating shaft being connected to the middle of the connecting rod, and the first tension wheel assembly located at the top being connected to the side plate.

[0012] As a further improvement of the present invention, the cylinder is an undamped cylinder.

[0013] As a further improvement of the present invention, each of the grinding mechanisms further includes a belt tensioning mechanism, which includes a tensioning cylinder and a second tensioning wheel connected to the output rod of the tensioning cylinder.

[0014] As a further improvement of the present invention, the frame is also provided with a correction mechanism.

[0015] As a further improvement of the present invention, it also includes a data acquisition and calculation control function module, a terminal block, a human-computer interaction system, and a control system. The displacement sensor and the control system are both connected to the data acquisition and calculation control function module. The force sensor and the torque motor are both connected to the data acquisition and calculation control function module through the terminal block. The data acquisition and calculation control function module is connected to the human-computer interaction system.

[0016] A method for controlling belt grinding, using the aforementioned grinding equipment, includes the following steps:

[0017] (1) The torque motor balances the gravity of the attitude adjustment mechanism and the contact wheel mechanism in real time, ensuring that the contact wheel mechanism can maintain its attitude at any position after being driven to any position under the thrust of the cylinder.

[0018] (2) When the complex curved surface workpiece to be processed is in contact with the abrasive belt, the grinding force at the output contact point is given;

[0019] (3) The actual output force of the cylinder is fed back through the force sensor, the current contact position of the contact point is fed back through the encoder of the torque motor, and the current extension / retraction position value of the cylinder is fed back through the displacement sensor.

[0020] (4) Calculate the output force required by the cylinder to output the contact wheel mechanism by means of the force sensor, the encoder of the torque motor and the feedback of the displacement sensor, the force conversion and force response transfer function.

[0021] As a further improvement of the present invention, the force sensor, the encoder of the torque motor, and the displacement sensor feedback equivalent conversion and force response transfer function are as follows:

[0022]

[0023] Among them, F 张 F is the tension of the abrasive belt. 气 F is the output force of the cylinder, and F is the net force on the contact wheel. t To reduce tangential force, F n To reduce the normal force, M 电机 The torque motor outputs a balanced torque, l1 to l7 are the lever arms of each axis, α is the encoder feedback angle, and d 触 Where F is the diameter of the contact wheel, mg is the combined gravity of the attitude adjustment mechanism and the contact wheel mechanism, and F is the total gravity. 气 'K' represents the actual output force of the cylinder, fed back by a force sensor. v denoted as amplifier gain coefficient, c0 as adjustment coefficient, s as transfer function variable, and d0, d1, and d2 as coefficients of each order.

[0024] The beneficial effects of this invention are:

[0025] (1) This invention solves the problem of rapid force response when the grinding force is constantly changing. By using a torque motor to balance gravity, the cylinder only needs to output a small thrust for grinding and respond quickly and promptly. It can effectively control the grinding amount with small changes, improve the grinding accuracy of the grinding contact point, and effectively adapt to the real-time changes of the target force required during the grinding control process, greatly improving the adaptability of grinding of complex curved surface workpieces.

[0026] (2) The present invention uses double contact wheel grinding and large circumference abrasive belt, which can effectively dissipate heat, extend the service life of abrasive belt and contact wheel during grinding of complex curved workpieces, and improve processing efficiency.

[0027] (3) The present invention has the advantages of high integration, compact structure and reliable performance, and can be effectively applied to small and medium-sized complex curved surfaces and components with high grinding precision requirements. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a perspective view of a preferred embodiment of the present invention;

[0030] Figure 2 This is a perspective view of a preferred embodiment of the present invention from another angle;

[0031] Figure 3 This is a cross-sectional side view of a preferred embodiment of the present invention;

[0032] Figure 4 This is a top sectional view of a preferred embodiment of the present invention;

[0033] Figure 5 This is a hardware and software connection diagram of a preferred embodiment of the present invention;

[0034] Figure 6 Force diagram of a single attitude adjustment mechanism and contact wheel mechanism according to a preferred embodiment of the present invention;

[0035] In the diagram: 1. Frame, 2. Grinding mechanism, 21. Torque motor, 211. Rotating shaft, 22. Force output mechanism, 221. Cylinder, 222. Displacement sensor, 224. Force sensor, 23. Attitude adjustment mechanism, 231. Support plate, 232. Pin, 233. Connecting rod, 234. Sleeve, 235. Bearing, 236. Support shaft, 237. First tensioning wheel, 24. Contact wheel mechanism, 241. Side plate, 242. Contact wheel, 243. Adjusting wheel, 25. Sanding belt tensioning mechanism, 251. Tensioning cylinder, 252. Second tensioning wheel, 3. Sanding belt, 4. Drive mechanism, 5. Correction mechanism, 51. Correction cylinder, 52. Rotating wheel, 6. Data acquisition and calculation control function module, 62. Terminal board, 63. Human-machine interaction system, 64. Control system. Detailed Implementation

[0036] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this invention.

[0037] Please see Figures 1-4 This application discloses a grinding belt polishing device, comprising:

[0038] Rack 1;

[0039] The grinding device includes two grinding mechanisms 2 arranged in the vertical direction. Each grinding mechanism 2 includes a torque motor 21, a force output mechanism 22, an attitude adjustment mechanism 23, and a contact wheel mechanism 24. The torque motor 21 and the force output mechanism 22 are both mounted on the frame 1. The torque motor 21 is equipped with an encoder. The rotating shaft 211 of the torque motor 21 is connected to the attitude adjustment mechanism 23. The force output mechanism 22 includes a cylinder 221, a displacement sensor 222 mounted on the cylinder 221, and a force sensor 224 connected to the piston rod of the cylinder 221. The force sensor 224 is hinged to the attitude adjustment mechanism 23. The attitude adjustment mechanism 23 is connected to the contact wheel mechanism 24. A sanding belt 3 is wound around both the attitude adjustment mechanism 23 and the contact wheel mechanism 24.

[0040] Drive mechanism 4 is used to drive the sanding belt 3 to move.

[0041] This invention utilizes a torque motor 21 to balance the gravity of the attitude adjustment mechanism 23 and the contact wheel mechanism 24. This allows for grinding during the grinding process, where a small thrust is output by the cylinder 221. This effectively adapts to real-time changes in the target force during grinding control and provides a rapid and timely response. By precisely controlling the output force of the cylinder 221, it effectively controls the grinding amount, which varies greatly even with small changes, improving the grinding accuracy at the grinding contact point and shortening the response time. Furthermore, this invention incorporates two grinding mechanisms 2, extending the circumference of the abrasive belt 3, effectively dissipating heat, extending the belt's lifespan, and enabling simultaneous grinding of two workpieces, thus improving processing efficiency.

[0042] In this embodiment, please refer to Figure 1 , Figure 4 Two support plates 231 are arranged opposite each other on one side of the attitude adjustment mechanism 23 in the front-back direction. The force sensor 224 is located at least partially between the two support plates 231. The force sensor 224 is connected to the support plate 231 by a pin 232.

[0043] Please see Figure 1 The contact wheel mechanism 24 includes a side plate 241, a contact wheel 242 disposed at one end of the side plate 241, and two adjusting wheels 243 disposed opposite each other on the side plate 241 in the vertical direction. The other end of the side plate 241 is connected to the other side of the attitude adjustment mechanism 23.

[0044] Preferably, the attitude adjustment mechanism 23 includes a connecting rod 233 extending in the vertical direction, two first tensioning wheel assemblies respectively connected to both ends of the connecting rod 233, a rotating shaft 211 connected to the middle of the connecting rod 233, and the upper first tensioning wheel assembly connected to the side plate 241. The attitude adjustment mechanism 23 and the contact wheel mechanism 24 are integrated, and the attitude adjustment mechanism 23 and the contact wheel mechanism 24 rotate around the axis of the rotating shaft 211 to realize the change of the overall position and attitude of the attitude adjustment mechanism 23 and the contact wheel mechanism 24. Preferably, the first tensioning wheel assembly includes a sleeve 234, a bearing 235 disposed in the sleeve 234, and a first tensioning wheel 237 connected to the bearing 235 through a support shaft 236.

[0045] Preferably, cylinder 221 is an undamped cylinder, which improves the stability of output force and the timeliness of response.

[0046] Preferably, each grinding mechanism 2 further includes a sanding belt tensioning mechanism 25, which includes a tensioning cylinder 251 and a second tensioning wheel 252 connected to the output rod of the tensioning cylinder 251. The tension of the sanding belt 3 is adjusted by driving the second tensioning wheel 252 to move through the tensioning cylinder 251.

[0047] To prevent the sanding belt 3 from deviating, a deviation correction mechanism 5 is preferably provided on the frame 1. The deviation correction mechanism 5 may include a deviation correction cylinder 51 and a rotating wheel 52 that rotates relative to the deviation correction cylinder 51. If the axis of the deviation correction cylinder 51 is set to the Y direction, then the direction perpendicular to the axis is set to the X direction. By adjusting the deviation correction cylinder 51 to rotate around the X direction, the sanding belt 3 can be returned to its original position.

[0048] Preferably, the encoder is an angle encoder. The angle encoder can be mounted on the rotating shaft 211.

[0049] Please see Figure 5 It also includes a data acquisition and processing control function module 61, a terminal block 62, a human-machine interaction system 63, and a control system 64. The displacement sensor 222 and the control system 64 are both connected to the data acquisition and processing control function module 61. The force sensor 224 and the torque motor 21 are both connected to the data acquisition and processing control function module 61 through the terminal block 62. The data acquisition and processing control function module 61 is connected to the human-machine interaction system 63.

[0050] First, by balancing the gravity of the torque motor 21, the attitude adjustment mechanism 23, and the contact wheel mechanism 24, when the complex curved surface workpiece to be processed comes into contact with the abrasive belt 3, the human-machine interaction system 63 provides the grinding force at the contact point. At the same time, the data acquisition and calculation control function module 61 collects data from the force sensor 224, the angle encoder, and the displacement sensor 222 respectively, and performs calculations to obtain the output force of the cylinder 221. The control system 64 controls the proportional solenoid valve and the reversing solenoid valve based on the magnitude of this output force, so that the cylinder 221 provides thrust to the contact wheel mechanism 24 to change the position and attitude between the contact wheel 242 and the complex curved surface workpiece to adapt to the changes in the concave and convex surfaces of the complex curved surface workpiece, effectively controlling the grinding amount with small changes and improving the grinding accuracy of the grinding contact point.

[0051] This application also discloses a method for controlling grinding belt polishing, using the above-mentioned polishing equipment, including the following steps:

[0052] (1) By using the torque motor 21 to balance the gravity of the attitude adjustment mechanism 23 and the contact wheel mechanism 24 in real time, it is ensured that under the thrust of the cylinder 221, the contact wheel mechanism 24 can maintain the attitude of the position at any position.

[0053] (2) When the complex curved surface workpiece to be processed is in contact with the abrasive belt 3, the grinding force at the output contact point is given;

[0054] (3) The actual output force of the cylinder 221 is fed back through the force sensor 224, the current contact position of the contact point is fed back through the encoder of the torque motor 21, and the current extension and retraction position value of the cylinder 221 is fed back through the displacement sensor 222.

[0055] (4) Calculate the output force required by the cylinder 221 to output the contact wheel mechanism 24 by using the force sensor 224, the encoder of the torque motor 21 and the displacement sensor 222 feedback of the equivalent force conversion and force response transfer function.

[0056] Preferably, the encoder is an angle encoder.

[0057] Please see Figure 6 The force sensor 224, the encoder of the torque motor 21, and the displacement sensor 222 feedback are converted into force response transfer functions as follows:

[0058]

[0059] Among them, F 张 F is the tension of the sanding belt 3. 气 F is the output force of cylinder 221, and F is the net force on contact wheel 242. t To reduce tangential force, F n To reduce the normal force, M 电机The torque motor 2 outputs a balanced torque, l1 to l7 are the lever arms of each axis, α is the encoder feedback angle, and d 触 Where F is the diameter of contact wheel 242, mg is the combined gravity of attitude adjustment mechanism 23 and contact wheel mechanism 24, and F is the total gravity of contact wheel 242. 气 'The force sensor 224 provides feedback on the actual output force of cylinder 221, K' v denoted as amplifier gain coefficient, c0 as adjustment coefficient, s as transfer function variable, and d0, d1, and d2 as coefficients of each order.

[0060] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention 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 included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0061] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for controlling grinding belt polishing, characterized in that, include: frame; A grinding device includes two grinding mechanisms arranged in a vertical direction. Each grinding mechanism includes a torque motor, a force output mechanism, a posture adjustment mechanism, and a contact wheel mechanism. The torque motor and the force output mechanism are both mounted on the frame. The torque motor is equipped with an encoder. The rotating shaft of the torque motor is connected to the posture adjustment mechanism. The force output mechanism includes a cylinder, a displacement sensor mounted on the cylinder, and a force sensor connected to the piston rod of the cylinder. The force sensor is hinged to the posture adjustment mechanism. The posture adjustment mechanism is connected to the contact wheel mechanism. A sanding belt is wound around both the posture adjustment mechanism and the contact wheel mechanism. A drive mechanism is used to drive the sanding belt to move; Includes the following steps: (1) The torque motor balances the gravity of the attitude adjustment mechanism and the contact wheel mechanism in real time, ensuring that the contact wheel mechanism can maintain its attitude at any position after being driven to any position under the thrust of the cylinder. (2) When the complex curved surface workpiece to be processed is in contact with the abrasive belt, the grinding force at the output contact point is given; (3) The actual output force of the cylinder is fed back through the force sensor, the current contact position of the contact point is fed back through the encoder of the torque motor, and the current extension and retraction position value of the cylinder is fed back through the displacement sensor; (4) Calculate the output force required by the cylinder to output the contact wheel mechanism by using the force sensor, the encoder of the torque motor and the feedback of the displacement sensor, the force conversion and force response transfer function; The force sensor, torque motor encoder, and displacement sensor feedback equivalent conversion and force response transfer function are as follows: in, The tension of the abrasive belt. The output force of the cylinder, The net force on the contact wheel, To reduce tangential force, To refine the normal force, To provide balanced torque for the torque motor output, ~ For each axial lever arm, For encoder feedback of rotation angle, The diameter of the contact wheel, The gravity is combined with the attitude adjustment mechanism and the contact wheel mechanism. The force sensor provides feedback on the actual output force of the cylinder. This is the amplifier gain coefficient. The adjustment coefficient is s, where s is the transfer function variable. , , These are the coefficients of each order.

2. The grinding belt polishing control method according to claim 1, characterized in that, Two support plates are arranged opposite each other on one side of the attitude adjustment mechanism in the front-to-back direction. The force sensor is located at least partially between the two support plates, and the force sensor is connected to the support plates by a pin.

3. The grinding belt polishing control method according to claim 1, characterized in that, The contact wheel mechanism includes a side plate, a contact wheel disposed at one end of the side plate, and two adjusting wheels disposed opposite each other on the side plate in the vertical direction. The other end of the side plate is connected to the other side of the attitude adjustment mechanism.

4. The grinding belt polishing control method according to claim 3, characterized in that, The attitude adjustment mechanism includes a connecting rod extending in the vertical direction, two first tension wheel assemblies respectively connected to both ends of the connecting rod, a rotating shaft connected to the middle of the connecting rod, and the first tension wheel assembly located at the top connected to the side plate.

5. The grinding belt polishing control method according to claim 1, characterized in that, The cylinder is an undamped cylinder.

6. The grinding belt polishing control method according to claim 1, characterized in that, Each of the grinding mechanisms further includes a belt tensioning mechanism, which includes a tensioning cylinder and a second tensioning wheel connected to the output rod of the tensioning cylinder.

7. The grinding belt polishing control method according to claim 1, characterized in that, The frame is also equipped with a correction mechanism.

8. The grinding belt polishing control method according to claim 1, characterized in that, It also includes a data acquisition and processing control function module, a terminal block, a human-machine interaction system, and a control system. The displacement sensor and the control system are both connected to the data acquisition and processing control function module. The force sensor and the torque motor are both connected to the data acquisition and processing control function module through the terminal block. The data acquisition and processing control function module is connected to the human-machine interaction system.

Images