A coiled material deviation rectifying system based on direct current servo drive

Abstract

The application discloses a kind of based on DC servo drive's coiled material deviation correction system, including deviation detection module, servo deviation correction control system and deviation correction execution mechanism, servo deviation correction control system includes deviation correction control module, servo drive module, DC servo motor, rotary encoder and current detection circuit;Deviation detection module is used to detect the position deviation signal of coiled material in the coiled material output end of target conveying roller, and position deviation signal is sent to servo deviation correction control system, servo drive module is used to control the rotation direction, rotational speed and torque of DC servo motor according to the PWM drive control signal output by deviation correction control module, to drive deviation correction execution mechanism by DC servo motor and carry out deviation correction control to coiled material.The application can make the torque output of DC servo motor more stable and not creep at low speed, and motor is more quickly responded at high speed, and can effectively improve the deviation correction accuracy of system, to effectively meet the high-precision requirement of deviation correction application.

Description

Technical Field

[0001] This invention relates to the field of web web alignment technology, and in particular to a web web alignment system based on DC servo drive. Background Technology

[0002] Currently, most drive motors used in the web web guiding industry are AC synchronous motors, stepper motors, and DC brushless motors. While these motors are simple to drive, their performance is difficult to improve. AC synchronous motors, with their fixed and slow speeds, are mainly used in low-speed bag-making machines and other equipment where web guiding speed is not critical. Stepper motors, while speed-adjustable, suffer from low torque and slow speed, also exhibiting significant limitations. DC brushless motors, on the other hand, suffer from low-speed vibration. When higher web guiding speeds are required, both AC synchronous motors and stepper motors face the problem of slow and unresolved web guiding speeds. Furthermore, when the load track is uneven, load variations significantly impact DC brushless motors, making it impossible to guarantee the final web guiding accuracy.

[0003] Therefore, how to achieve rapid and high-precision web correction for roll materials is a problem that urgently needs to be solved in this field. Summary of the Invention

[0004] This invention aims to at least solve the technical problems existing in the prior art, and innovatively proposes a roll material correction system based on DC servo drive, which makes the motor output torque more stable and does not creep at low speed, and the motor responds faster at high speed, and can effectively improve the correction accuracy of the system.

[0005] To achieve the above-mentioned objectives of this invention, this invention provides a web correction system based on DC servo drive, comprising an offset detection module, a servo correction control system, and a correction execution mechanism, wherein...

[0006] The offset detection module is used to detect the position offset signal of the roll at the output end of the target conveyor roller and send the position offset signal to the servo correction control system. The position offset signal includes offset distance and offset direction.

[0007] The servo-guided web correction control system includes a web correction control module, a servo drive module, a DC servo motor, a rotary encoder, and a current detection circuit. The signal output terminals of the offset detection module, the rotary encoder, and the current detection circuit are respectively connected to the signal input terminal of the web correction control module. The signal output terminal of the web correction control module is connected to the signal input terminal of the servo drive module. The signal output terminal of the servo drive module is connected to the signal input terminal of the DC servo motor. The output shaft of the DC servo motor is drively connected to the web correction actuator.

[0008] The rotary encoder is mounted on the output shaft of the DC servo motor. It is used to detect the rotation angle information of the output shaft of the DC servo motor and convert the rotation angle information into a corresponding position signal, which is then fed back to the correction control module.

[0009] The input terminal of the current detection circuit is connected to the servo drive module. It is used to detect the drive current signal output by the servo drive module to the DC servo motor, and to feed back the detected drive current signal to the correction control module.

[0010] The correction control module generates a PWM drive control signal for controlling the operation of the servo drive module based on the position offset signal detected by the offset detection module. The PWM drive control signal includes a correction speed command and a correction position command. The correction control module further adjusts the correction speed command and correction position command of the PWM drive control signal based on the feedback position signal and drive current signal.

[0011] The servo drive module is used to control the rotation direction, speed and torque of the DC servo motor according to the PWM drive control signal, so as to drive the correction actuator to perform correction control on the roll material through the DC servo motor.

[0012] Preferably, the offset detection module includes a sensor detection unit, a display calibration unit, and an offset calculation unit, wherein,

[0013] The sensor detection unit includes a first CCD sensor group and a second CCD sensor group; the first CCD sensor group includes a first linear array CCD sensor and a second linear array CCD sensor spaced apart on a first side of the roll at the roll output end of the target conveyor roller, the first linear array CCD sensor and the second linear array CCD sensor being used to detect a first position offset signal and a second position offset signal of the edge of the first side of the roll, respectively; the second CCD sensor group includes a third linear array CCD sensor and a fourth linear array CCD sensor spaced apart on a second side of the roll opposite to the first side at the roll output end of the target conveyor roller, the third linear array CCD sensor and the fourth linear array CCD sensor being used to detect a third position offset signal and a fourth position offset signal of the edge of the second side of the roll, respectively;

[0014] The display calibration unit is used to display the roll edge images at corresponding positions in the un-offset state of the roll material captured by the first linear array CCD sensor, the second linear array CCD sensor, the third linear array CCD sensor, and the fourth linear array CCD sensor of the first CCD sensor group, and to mark the roll edge points at corresponding positions on the corresponding roll edge images captured by each linear array CCD sensor based on human-computer interaction, and to record the corresponding coordinates of each roll edge point in the rectangular plane coordinate system.

[0015] The offset calculation unit is used to calculate the position offset signal of the roll at the roll output end of the target conveying roller during the roll conveying process, based on the first position offset signal, second position offset signal, third position offset signal, and fourth position offset signal detected by the first linear array CCD sensor, the second linear array CCD sensor, the third linear array CCD sensor, and the fourth linear array CCD sensor of the first CCD sensor group, as well as the corresponding coordinates of the roll edge points in the rectangular plane coordinate system recorded by the display calibration unit.

[0016] Preferably, the offset calculation unit is specifically used for:

[0017] During the roll material conveying process, the first offset corresponding to the first roll material edge point is calculated based on the first position offset signal detected by the first linear CCD sensor and the first coordinate of the first roll material edge point in the rectangular plane coordinate system in the first roll material edge image of the first roll material edge point at the corresponding position in the roll material unoffset state captured by the first linear CCD sensor and recorded by the display calibration unit.

[0018] During the roll material conveying process, the second offset corresponding to the second roll material edge point is calculated based on the second position offset signal detected by the second linear CCD sensor and the second coordinates of the second roll material edge point in the rectangular plane coordinate system in the second roll material edge image of the corresponding position when the roll material is not offset, as recorded by the display calibration unit;

[0019] During the roll material conveying process, the third offset corresponding to the third roll material edge point is calculated based on the third position offset signal detected by the third linear CCD sensor and the third coordinate of the third roll material edge point in the rectangular plane coordinate system in the third roll material edge image of the corresponding position when the roll material is not offset, as recorded by the display calibration unit.

[0020] During the roll material conveying process, the fourth offset corresponding to the fourth roll material edge point is calculated based on the fourth position offset signal detected by the fourth linear CCD sensor and the fourth coordinate of the fourth roll material edge point in the rectangular plane coordinate system in the fourth roll material edge image of the corresponding position when the roll material is not offset, as recorded by the display calibration unit.

[0021] The first offset and the second offset are fitted according to a preset fitting coefficient to generate the fitted offset of the first side of the roll material;

[0022] The third offset and the fourth offset are fitted according to a preset fitting coefficient to generate the fitted offset of the second side of the roll material;

[0023] The fitting offset of the first side and the fitting offset of the second side are fitted according to a preset fitting coefficient to generate the position offset signal of the roll output end of the target conveyor roller.

[0024] Preferably, the DC servo motor employs a 3-loop control system, and the correction control module includes a first adder, a second adder, a third adder, a position PID controller, a speed PID controller, and a differentiator.

[0025] The servo drive module, DC servo motor, and current detection circuit are connected in sequence. The output of the current detection circuit is then input to the servo drive module via the first adder, forming a current loop located in the inner loop.

[0026] The speed PID controller, DC servo motor, rotary encoder, and differentiator are connected in sequence. The output of the differentiator is then input to the speed PID controller via the second adder, forming a speed loop located in the middle loop.

[0027] The position PID controller, DC servo motor, and rotary encoder are connected in sequence. The output of the rotary encoder is then input to the position PID controller via the third adder to form a position loop located on the outer ring.

[0028] Preferably, the servo drive module includes a MOSFET drive circuit, a MOSFET switching circuit, and a motor brake control circuit. The input terminal of the MOSFET drive circuit is connected to the output terminal of the correction control module, the output terminal of the MOSFET drive circuit is connected to the input terminal of the MOSFET switching circuit, the first output terminal of the MOSFET switching circuit is connected to the input terminal of the DC servo motor, the second output terminal of the MOSFET switching circuit is connected to the input terminal of the current detection circuit, the input terminal of the motor brake control circuit is connected to the output terminal of the correction control module, and the output terminal of the motor brake control circuit is connected to the DC servo motor.

[0029] The MOSFET driving circuit is used to perform level conversion on the PWM driving control signal output by the correction control module. The converted PWM driving control signal controls the opening and closing of the MOSFET switching circuit, thereby adjusting the driving current of the DC servo motor and controlling the rotation direction, speed and torque of the DC servo motor.

[0030] The motor brake control circuit is used to control the DC servo motor to stop rotating based on the brake signal output by the correction control module.

[0031] Preferably, the correction actuator includes a base, a moving platform, a driving gear, a driven gear, a lead screw pair, and the target conveying roller. The moving platform, DC servo motor, driving gear, driven gear, and lead screw pair are all mounted on the base. The output shaft of the DC servo motor is fixedly connected to the driving gear. The driving gear meshes with the driven gear. The driven gear is fixedly connected to the drive end of the lead screw of the lead screw pair. The nut of the lead screw pair is fixedly connected to the moving platform. The moving platform is slidably connected to the top surface of the base via a slide rail. The target conveying roller is rotatably mounted on the moving platform.

[0032] Preferably, the step of generating a PWM drive control signal for controlling the operation of the servo drive module based on the position offset signal detected by the offset detection module includes:

[0033] The rotation direction and the number of revolutions required for the DC servo motor are calculated based on the position offset signal detected by the offset detection module and the transmission ratio between the drive gear and the transmission gear.

[0034] The number of Hall pulses required to drive the DC servo motor is calculated based on the calculated number of rotations required by the DC servo motor and the number of Hall pulses required for one rotation of the DC servo motor.

[0035] The PWM drive control signal is generated based on the calculated number of Hall pulses required to drive the DC servo motor and the rotation direction of the DC servo motor.

[0036] Preferably, the rotary encoder is a 1000-line magnetic encoder or a 2500-line magnetic encoder.

[0037] The present invention relates to a DC servo-driven roll web correction system. This system combines a DC servo motor with a rotary encoder. An offset detection module detects the position offset signal of the roll web at the output end of the target conveyor roller. The rotary encoder detects the position signal of the output shaft of the DC servo motor in real time and feeds it back to the correction control module. A current detection circuit detects the drive current signal of the DC servo motor in real time and feeds it back to the correction control module. During the correction process, the correction control module dynamically adjusts the rotation direction, speed, and torque of the DC servo motor by combining the position offset signal, the feedback position signal, and the drive current signal. This allows the DC servo motor of the roll web correction system to respond quickly at low speeds without jitter, and respond more promptly at high speeds. This enables rapid and high-precision correction of various roll webs, effectively meeting the high-precision requirements of correction applications. In certain roll web fields (such as lithium battery manufacturing and capacitor manufacturing), it can more precisely control the left and right position of the roll web to control the final product quality and reduce waste.

[0038] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0039] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0040] Figure 1 This is a schematic diagram of a web correction system based on DC servo drive in a preferred embodiment of the present invention.

[0041] Figure 2 This is a schematic diagram of the arrangement of each linear CCD sensor in the sensor detection unit of the offset detection module in a preferred embodiment of the present invention.

[0042] Figure 3 This is a block diagram of the control principle of the three-way switching control used in the correction control module in a preferred embodiment of the present invention;

[0043] Figure 4 This is a circuit diagram of the main control chip of the correction control module in a specific embodiment of the present invention;

[0044] Figure 5This is a circuit schematic diagram of a MOSFET driving circuit in a specific example provided by the present invention;

[0045] Figure 6 This is a circuit schematic diagram of a MOSFET switching circuit in a specific example provided by the present invention;

[0046] Figure 7 This is a circuit diagram of a motor brake control circuit in a specific embodiment provided by the present invention;

[0047] Figure 8 This is a circuit diagram of a current detection circuit in a specific embodiment provided by the present invention;

[0048] Figure 9 This is a circuit diagram of an external input / output control circuit in a specific example provided by the present invention. Detailed Implementation

[0049] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0050] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the meaning consistent with their meaning in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless specifically defined.

[0051] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention 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. Therefore, they should not be construed as limitations on this invention.

[0052] In the description of this invention, unless otherwise specified and limited, it should be noted that the terms "installation", "connection" and "linking" should be interpreted broadly. For example, they can refer to mechanical or electrical connections, or internal connections between two components. They can be direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0053] This invention provides a web correction system based on DC servo drive, such as... Figure 1-9 As shown, the system includes an offset detection module 1, a servo correction control system 2, and a correction execution mechanism 3.

[0054] The offset detection module 1 is used to detect the position offset signal of the roll at the output end of the roll of the target conveyor roller 36 and send the position offset signal to the servo correction control system 2. The position offset signal includes the offset distance and offset direction.

[0055] The servo-guided web correction control system 2 includes a web correction control module 21, a servo drive module 22, a DC servo motor 23, a rotary encoder 24, and a current detection circuit 25. The signal output terminals of the offset detection module 21, the rotary encoder 24, and the current detection circuit 25 are respectively connected to the signal input terminal of the web correction control module 21. The signal output terminal of the web correction control module 21 is connected to the signal input terminal of the servo drive module 22. The signal output terminal of the servo drive module 22 is connected to the signal input terminal of the DC servo motor 23. The output shaft of the DC servo motor 23 is connected to the web correction actuator 3 via a transmission connection.

[0056] The rotary encoder 24 is mounted on the output shaft of the DC servo motor 23. It is used to detect the rotation angle information of the output shaft of the DC servo motor 23 and convert the rotation angle information into a corresponding position signal, which is then fed back to the correction control module 21.

[0057] The input terminal of the current detection circuit 25 is connected to the servo drive module 22. It is used to detect the drive current signal output by the servo drive module 22 to the DC servo motor 23, and to feed back the detected drive current signal to the correction control module 21.

[0058] The correction control module 21 generates a PWM drive control signal for controlling the operation of the servo drive module 22 based on the position offset signal detected by the offset detection module 1. The PWM drive control signal includes a correction speed command and a correction position command. The correction control module 21 also adjusts the correction speed command and correction position command of the PWM drive control signal based on the feedback position signal and drive current signal.

[0059] The servo drive module 22 is used to control the rotation direction, speed and torque of the DC servo motor 23 according to the PWM drive control signal, so as to drive the web correction actuator 3 to perform web correction control on the roll material through the DC servo motor 23.

[0060] This embodiment of the roll material correction system based on DC servo drive combines a DC servo motor 23 with a rotary encoder 24. The offset detection module 1 detects the position offset signal of the roll material at the output end of the target conveyor roller 36. The rotary encoder 24 detects the position signal of the output shaft of the DC servo motor 23 in real time and feeds it back to the correction control module 21. The current detection circuit 25 detects the drive current signal of the DC servo motor 23 in real time and feeds it back to the correction control module 21. Therefore, during the correction process, the correction control module 21 combines the position offset signal and the feedback... The position signal and drive current signal dynamically adjust the rotation direction, speed and torque of the DC servo motor 23. Due to the advantages of servo motors such as high rigidity, fast response and controllable torque, the DC servo motor 23 of the roll material correction system can respond quickly at low speeds without jitter and respond more promptly at high speeds. This enables fast and high-precision correction of various roll materials, effectively meeting the high-precision requirements of correction applications. In some roll material fields (such as lithium battery manufacturing, capacitor manufacturing, etc.), the left and right positions of the roll material can be controlled more precisely to control the quality of the final product and reduce waste.

[0061] In this embodiment, as Figure 2 As shown, the web-correcting actuator 3 includes a base 31, a moving platform 32, a driving gear 33, a driven gear 34, a lead screw pair 35, and a target conveying roller 36. The moving platform 32, DC servo motor 23, driving gear 33, driven gear 34, and lead screw pair 35 are all mounted on the base 31. The output shaft of the DC servo motor 23 is fixedly connected to the driving gear 33. The driving gear 33 meshes with the driven gear 34. The driven gear 34 is fixedly connected to the drive end of the lead screw of the lead screw pair 35. The nut of the lead screw pair 35 is fixedly connected to the moving platform 32. The moving platform 32 is slidably connected to the top surface of the base 31 via a slide rail. The target conveying roller 36 is rotatably mounted on the moving platform 32. The DC servo motor 23 drives the driving gear 33, which in turn drives the driven gear 34 to rotate. The rotation of the driven gear 34 drives the lead screw of the lead screw pair 35 to rotate, thereby causing the moving platform 32, which is fixedly connected to the nut of the lead screw pair 35, to move linearly along the width direction of the roll material, thus achieving web-correcting.

[0062] Specifically, in this embodiment, generating a PWM drive control signal for controlling the operation of the servo drive module 22 based on the position offset signal detected by the offset detection module 1 includes:

[0063] The rotation direction and the number of revolutions required for the DC servo motor 23 are calculated based on the position offset signal detected by the offset detection module 1 and the transmission ratio between the drive gear 33 and the transmission gear.

[0064] The number of Hall pulses required to drive the DC servo motor 23 is calculated based on the number of rotations required for the DC servo motor 23 and the number of Hall pulses required for the DC servo motor 23 to rotate one revolution.

[0065] A PWM drive control signal is generated based on the calculated number of Hall pulses required to drive the DC servo motor 23 and the rotation direction of the DC servo motor 23.

[0066] By calculating the number of Hall pulses required to drive the DC servo motor 23 and the rotation direction of the DC servo motor 23, the generated PWM drive control signal can more accurately control the correction accuracy.

[0067] In one embodiment, such as Figure 1 , 2 As shown, the offset detection module 1 includes a sensor detection unit 11, a display calibration unit 12, and an offset calculation unit 13, wherein...

[0068] The sensor detection unit 11 includes a first CCD sensor group 111 and a second CCD sensor group 112. The first CCD sensor group 111 includes a first linear array CCD sensor 1111 and a second linear array CCD sensor 1112 spaced apart on the first side of the roll at the roll output end of the target conveyor roller 36. The first linear array CCD sensor 1111 and the second linear array CCD sensor 1112 are used to detect a first position offset signal and a second position offset signal of the edge of the first side of the roll, respectively. The second CCD sensor group 112 includes a third linear array CCD sensor 1121 and a fourth linear array CCD sensor 1122 spaced apart on the second side of the roll at the roll output end of the target conveyor roller 36 opposite to the first side. The third linear array CCD sensor 1121 and the fourth linear array CCD sensor 1122 are used to detect a third position offset signal and a fourth position offset signal of the edge of the second side of the roll, respectively.

[0069] The display calibration unit 12 is used to display the roll edge images at corresponding positions in the un-offset state of the roll material captured by the first linear array CCD sensor 1111, the second linear array CCD sensor 1112, the third linear array CCD sensor 1121, and the fourth linear array CCD sensor 1122 of the first CCD sensor group 111. Based on human-computer interaction, the unit 12 marks the roll edge points at corresponding positions on the corresponding roll edge images captured by each linear array CCD sensor and records the corresponding coordinates of each roll edge point in the rectangular plane coordinate system.

[0070] The offset calculation unit 13 is used to calculate the position offset signal of the roll at the output end of the target conveying roller 36 by fitting the first position offset signal, the second position offset signal, the third position offset signal, and the fourth position offset signal detected by the first linear array CCD sensor 1111, the second linear array CCD sensor 1112, the third linear array CCD sensor 1121 and the fourth linear array CCD sensor 1122 of the first CCD sensor group 111, and the corresponding coordinates of the roll edge points in the rectangular plane coordinate system recorded by the display calibration unit 12 during the roll conveying process.

[0071] In this embodiment, the offset calculation unit 13 is specifically used for:

[0072] During the roll material transport process, the first offset corresponding to the first roll material edge point is calculated based on the first position offset signal detected by the first linear CCD sensor 1111 and the first coordinate of the first roll material edge point in the rectangular plane coordinate system in the first roll material edge image captured by the first linear CCD sensor 1111 at the corresponding position when the roll material is not offset, as recorded by the display calibration unit 12.

[0073] During the roll material transport process, the second offset amount corresponding to the second roll material edge point is calculated based on the second position offset signal detected by the second linear CCD sensor 1112 and the second coordinates of the second roll material edge point in the rectangular plane coordinate system in the second roll material edge image captured by the second linear CCD sensor 1112 at the corresponding position when the roll material is not offset, as recorded by the display calibration unit 12.

[0074] During the roll material transport process, the third offset corresponding to the third roll material edge point is calculated based on the third position offset signal detected by the third linear CCD sensor 1121 and the third coordinate of the third roll material edge point in the rectangular plane coordinate system in the third roll material edge image of the corresponding position when the roll material is not offset, as recorded by the display calibration unit 12.

[0075] During the roll material transport process, the fourth offset corresponding to the fourth roll material edge point is calculated based on the fourth position offset signal detected by the fourth linear CCD sensor 1122 and the fourth coordinate of the fourth roll material edge point in the rectangular plane coordinate system in the image of the fourth roll material edge point at the corresponding position when the roll material is not offset, as recorded by the display calibration unit 12.

[0076] The first offset and the second offset are fitted according to a preset fitting coefficient to generate the fitted offset of the first side of the roll material;

[0077] The third offset and the fourth offset are fitted according to the preset fitting coefficient to generate the fitted offset of the second side of the roll material;

[0078] The fitting offsets of the first side and the second side are fitted according to the preset fitting coefficients to generate the roll position offset signal of the roll output end of the target conveyor roller 36.

[0079] Specifically, the aforementioned fitting coefficients can be obtained by processing multiple offsets corresponding to multiple measurements.

[0080] In this embodiment, a first CCD sensor group 111 located on one side of the roll at the roll output end and a second CCD sensor group 112 located on the other side of the roll at the roll output end are used to detect the position offset signal of the corresponding side of the roll. The position offset signals detected by the two CCD sensor groups are fitted according to a preset fitting coefficient to determine the actual offset of the roll. Each CCD sensor group is equipped with two spaced linear CCD sensors to detect the position offset signals at different positions on the same side. The position offset signals detected by the two linear CCD sensors of each group at two different positions are fitted according to a preset fitting coefficient to determine the roll offset on that side. This configuration can effectively avoid the problem of inaccurate roll offset detection caused by a single sensor detecting the offset on one side of the roll to determine the actual offset of the roll. It can effectively improve the accuracy of the position offset signal of the roll detected by the offset detection module, thereby improving the correction accuracy of the correction system from the source. In existing technologies, a single photoelectric sensor or ultrasonic sensor is typically used to detect the offset of the roll material. This is prone to detection errors and has limited accuracy. Furthermore, photoelectric sensors are not suitable for transparent roll materials, while ultrasonic sensors are not suitable for breathable roll materials. In this embodiment, the high resolution of a linear CCD sensor in the linear direction is utilized. Four linear CCD sensors are used to form two sets of CCD sensor groups, which together form the offset detection module 1 to detect the offset on both sides of the roll material. Compared to existing technologies that use a single photoelectric sensor or ultrasonic sensor to detect the offset of the roll material, this method has higher accuracy, overcomes the limitations of roll material transparency and material, and has a wider range of applications.

[0081] In one embodiment, such as Figure 3 As shown, the DC servo motor 23 adopts a 3-loop control, and the correction control module 21 includes a first adder 211, a second adder 212, a third adder 213, a position PID regulator 214, a speed PID regulator 215, and a differentiator 216.

[0082] Specifically, the servo drive module 22, the DC servo motor 23, and the current detection circuit 25 are connected in sequence. The output of the current detection circuit 25 is then input to the servo drive module 22 via the first adder 211 to form a current loop in the inner loop. The torque of the DC servo motor 23 is controlled through the current loop. Based on the drive current of the DC servo motor 23 detected by the current detection circuit 25, the torque of the DC servo motor 23 during the correction process is controlled by PID closed loop, which effectively improves the response speed of the DC servo motor 23 in torque mode of the correction system.

[0083] Specifically, the speed PID controller 215, DC servo motor 23, rotary encoder 24, and differentiator 216 are connected in sequence. The output of the differentiator 216 is then input to the speed PID controller 215 via the second adder 212 to form a speed loop in the middle loop. The speed loop detects the rotation angle position of the DC servo motor 23 through the rotary encoder 24, and then calculates the speed of the DC servo motor 23 through the differentiator 216. Based on the speed calculated by the differential, the speed of the DC servo motor 23 is controlled by PID closed loop during the correction process, thereby improving the speed control accuracy.

[0084] The position PID controller 214, the DC servo motor 23, and the rotary encoder 24 are connected in sequence. The output of the rotary encoder 24 is then input to the position PID controller 214 via the third adder 213 to form a position loop located on the outer loop. The position loop detects the rotation angle position of the DC servo motor 23 through the rotary encoder 24, and then performs PID closed-loop control on the correction position of the DC servo motor 23 during the correction process based on the detected actual rotation angle position of the DC servo motor 23, thereby improving the accuracy of the correction position control.

[0085] In this embodiment, the operation of the DC servo motor 23 used for correction adopts a three-loop PID closed-loop control consisting of a current loop, a speed loop, and a position loop. This is because the motor drive current, motor speed, and motor rotation angle position are interrelated. The current loop controls the motor quickly and accurately according to the command of the speed loop, and the speed loop controls the motor quickly and accurately according to the command speed of the position loop, so that it is not affected by the load and quickly tracks the change of the command speed. The position loop compares the detection signal with the given value and outputs the command speed of the speed loop, so that the position of the actuator is consistent with the command position.

[0086] In one embodiment, such as Figure 1As shown, the servo drive module 22 includes a MOSFET drive circuit 221, a MOSFET switch circuit 222, and a motor brake control circuit 223. The input terminal of the MOSFET drive circuit 221 is connected to the output terminal of the correction control module 21, the output terminal of the MOSFET drive circuit 221 is connected to the input terminal of the MOSFET switch circuit 222, the first output terminal of the MOSFET switch circuit 222 is connected to the input terminal of the DC servo motor 23, the second output terminal of the MOSFET switch circuit 222 is connected to the input terminal of the current detection circuit 25, the input terminal of the motor brake control circuit 223 is connected to the output terminal of the correction control module 21, and the output terminal of the motor brake control circuit 223 is connected to the DC servo motor 23.

[0087] Specifically, the MOSFET driving circuit 221 is used to perform level conversion on the PWM driving control signal output by the correction control module 21. The converted PWM driving control signal controls the opening and closing of the MOSFET switching circuit 222, thereby adjusting the drive current of the DC servo motor 23 and controlling the rotation direction, speed, and torque of the DC servo motor 23. In this embodiment, the circuit schematic of the MOSFET driving circuit 221 is as follows: Figure 5 As shown, the circuit schematic of the MOSFET switching circuit 222 is as follows. Figure 6 As shown, the MOSFET drive circuit 221 uses three drive circuits to drive the MOSFET switches of the three half-bridge switch circuits of the MOSFET switch circuit 222 to turn on and off, thereby controlling the current of the three phases U, V and W of the DC servo motor.

[0088] Specifically, the motor brake control circuit 223 is used to control the DC servo motor 23 to stop rotating based on the brake signal output by the correction control module 21. In this embodiment, the circuit diagram of the motor brake control circuit 223 is as follows: Figure 7 As shown, the motor brake control circuit 223 can quickly stop the DC servo motor 23 after the correction actuator 3 moves to the target position, thereby ensuring the correction accuracy.

[0089] Specifically, in this embodiment, the circuit diagram of the current detection circuit 25 is as follows: Figure 8 As shown, the current detection circuit 25 detects and amplifies the three-phase drive currents IU, IV, and IW output by the MOSFET switching circuit 222 of the servo drive module 22 through a three-channel current sampling and amplification circuit, and feeds the amplified drive current signal back to the correction control module 21, thereby realizing closed-loop control of the drive current.

[0090] Specifically, in this embodiment, the main control chip of the correction control module 21 is an STM32 series microcontroller, and its circuit schematic is shown below. Figure 4As shown.

[0091] Specifically, in one embodiment, the rotary encoder 24 employs a 1000-line magnetic encoder or a 2500-line magnetic encoder. Both 1000-line and 2500-line magnetic encoders offer high resolution and cost-effectiveness, significantly reducing costs while maintaining correction accuracy. The STM32 series microcontroller uses an ARM Cortex-M core, meeting the requirements of embedded application design and offering advantages such as high performance, low cost, and low power consumption.

[0092] Specifically, such as Figure 1 As shown, in one embodiment, the servo correction control system further includes an external input / output control circuit 26. The external input / output control circuit 26 is communicatively connected to the correction control module 21. The correction control module 21 establishes a communication connection with an external monitoring system or remote control system through the external input / output control circuit 26, realizing the interaction of data and commands between the correction system and the external monitoring system or remote control system, thereby facilitating remote monitoring of the correction system. Specifically, the circuit diagram of the external input / output control circuit 26 is shown below. Figure 9 As shown, each signal channel uses an optocoupler to achieve opto-isolation between the correction system and external system signals, reducing the interference of external system signals on the signals of this correction system, thereby ensuring the accuracy of correction control.

[0093] In this embodiment, if the module / unit integrated in the DC servo-driven web guiding system is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the above embodiments can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying the computer program code, a recording medium, a USB flash drive, a portable hard drive, a magnetic disk, an optical disk, a computer memory, a read-only memory (ROM), a random access memory (RAM), an electrical carrier signal, a telecommunication signal, and a software distribution medium, etc. It should be noted that the content contained in the computer-readable medium may be appropriately added to or subtracted from the content as required by the legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium may not include electrical carrier signals and telecommunication signals.

[0094] Those skilled in the art will understand that although some embodiments herein include certain features included in other embodiments but not others, combinations of features from different embodiments are intended to be within the scope of the invention and form different embodiments. For example, in the following claims, any of the claimed embodiments can be used in any combination.

[0095] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A web web guiding system based on DC servo drive, characterized in that, It includes an offset detection module, a servo correction control system, and a correction actuator, among which, The offset detection module is used to detect the position offset signal of the roll at the output end of the target conveyor roller and send the position offset signal to the servo correction control system. The position offset signal includes offset distance and offset direction. The servo-guided web correction control system includes a web correction control module, a servo drive module, a DC servo motor, a rotary encoder, and a current detection circuit. The signal output terminals of the offset detection module, the rotary encoder, and the current detection circuit are respectively connected to the signal input terminal of the web correction control module. The signal output terminal of the web correction control module is connected to the signal input terminal of the servo drive module. The signal output terminal of the servo drive module is connected to the signal input terminal of the DC servo motor. The output shaft of the DC servo motor is drively connected to the web correction actuator. The rotary encoder is mounted on the output shaft of the DC servo motor. It is used to detect the rotation angle information of the output shaft of the DC servo motor and convert the rotation angle information into a corresponding position signal, which is then fed back to the correction control module. The input terminal of the current detection circuit is connected to the servo drive module. It is used to detect the drive current signal output by the servo drive module to the DC servo motor, and to feed back the detected drive current signal to the correction control module. The correction control module generates a PWM drive control signal for controlling the operation of the servo drive module based on the position offset signal detected by the offset detection module. The PWM drive control signal includes a correction speed command and a correction position command. The correction control module further adjusts the correction speed command and correction position command of the PWM drive control signal based on the feedback position signal and drive current signal. The servo drive module is used to control the rotation direction, speed and torque of the DC servo motor according to the PWM drive control signal, so as to drive the correction actuator to perform correction control on the roll material through the DC servo motor; The offset detection module includes a sensor detection unit, a display calibration unit, and an offset calculation unit, wherein... The sensor detection unit includes a first CCD sensor group and a second CCD sensor group; the first CCD sensor group includes a first linear array CCD sensor and a second linear array CCD sensor spaced apart on a first side of the roll at the roll output end of the target conveyor roller, the first linear array CCD sensor and the second linear array CCD sensor being used to detect a first position offset signal and a second position offset signal of the edge of the first side of the roll, respectively; the second CCD sensor group includes a third linear array CCD sensor and a fourth linear array CCD sensor spaced apart on a second side of the roll opposite to the first side at the roll output end of the target conveyor roller, the third linear array CCD sensor and the fourth linear array CCD sensor being used to detect a third position offset signal and a fourth position offset signal of the edge of the second side of the roll, respectively; The display calibration unit is used to display the roll edge images at corresponding positions in the un-offset state of the roll material captured by the first linear array CCD sensor, the second linear array CCD sensor, the third linear array CCD sensor, and the fourth linear array CCD sensor of the first CCD sensor group, and to mark the roll edge points at corresponding positions on the corresponding roll edge images captured by each linear array CCD sensor based on human-computer interaction, and to record the corresponding coordinates of each roll edge point in the rectangular plane coordinate system. The offset calculation unit is used to calculate the roll position offset signal at the roll output end of the target conveying roller during the roll conveying process, based on the first position offset signal, second position offset signal, third position offset signal, and fourth position offset signal detected by the first linear array CCD sensor, the second linear array CCD sensor, the third linear array CCD sensor, and the fourth linear array CCD sensor of the first CCD sensor group, as well as the corresponding coordinates of the roll edge points in the rectangular plane coordinate system recorded by the display calibration unit. The offset calculation unit is specifically used for: During the roll material conveying process, the first offset corresponding to the first roll material edge point is calculated based on the first position offset signal detected by the first linear CCD sensor and the first coordinate of the first roll material edge point in the rectangular plane coordinate system in the first roll material edge image of the first roll material edge point at the corresponding position in the roll material unoffset state captured by the first linear CCD sensor and recorded by the display calibration unit. During the roll material conveying process, the second offset corresponding to the second roll material edge point is calculated based on the second position offset signal detected by the second linear CCD sensor and the second coordinates of the second roll material edge point in the rectangular plane coordinate system in the second roll material edge image of the corresponding position when the roll material is not offset, as recorded by the display calibration unit; During the roll material conveying process, the third offset corresponding to the third roll material edge point is calculated based on the third position offset signal detected by the third linear CCD sensor and the third coordinate of the third roll material edge point in the rectangular plane coordinate system in the third roll material edge image of the corresponding position when the roll material is not offset, as recorded by the display calibration unit. During the roll material conveying process, the fourth offset corresponding to the fourth roll material edge point is calculated based on the fourth position offset signal detected by the fourth linear CCD sensor and the fourth coordinate of the fourth roll material edge point in the rectangular plane coordinate system in the fourth roll material edge image of the corresponding position when the roll material is not offset, as recorded by the display calibration unit. The first offset and the second offset are fitted according to a preset fitting coefficient to generate the fitted offset of the first side of the roll material; The third offset and the fourth offset are fitted according to a preset fitting coefficient to generate the fitted offset of the second side of the roll material; The fitting offset of the first side and the fitting offset of the second side are fitted according to a preset fitting coefficient to generate the position offset signal of the roll output end of the target conveyor roller.

2. The web winding correction system based on DC servo drive according to claim 1, characterized in that, The DC servo motor employs a 3-loop control system. The correction control module includes a first adder, a second adder, a third adder, a position PID controller, a speed PID controller, and a differentiator. The servo drive module, DC servo motor, and current detection circuit are connected in sequence. The output of the current detection circuit is then input to the servo drive module via the first adder, forming a current loop located in the inner loop. The speed PID controller, DC servo motor, rotary encoder, and differentiator are connected in sequence. The output of the differentiator is then input to the speed PID controller via the second adder, forming a speed loop located in the middle loop. The position PID controller, DC servo motor, and rotary encoder are connected in sequence. The output of the rotary encoder is then input to the position PID controller via the third adder to form a position loop located on the outer ring.

3. The web guiding system based on DC servo drive according to claim 1, characterized in that, The servo drive module includes a MOSFET drive circuit, a MOSFET switching circuit, and a motor brake control circuit. The input terminal of the MOSFET drive circuit is connected to the output terminal of the correction control module, and the output terminal of the MOSFET drive circuit is connected to the input terminal of the MOSFET switching circuit. The first output terminal of the MOSFET switching circuit is connected to the input terminal of the DC servo motor, and the second output terminal of the MOSFET switching circuit is connected to the input terminal of the current detection circuit. The input terminal of the motor brake control circuit is connected to the output terminal of the correction control module, and the output terminal of the motor brake control circuit is connected to the DC servo motor. The MOSFET driving circuit is used to perform level conversion on the PWM driving control signal output by the correction control module. The converted PWM driving control signal controls the opening and closing of the MOSFET switching circuit, thereby adjusting the driving current of the DC servo motor and controlling the rotation direction, speed and torque of the DC servo motor. The motor brake control circuit is used to control the DC servo motor to stop rotating based on the brake signal output by the correction control module.

4. The web guiding system based on DC servo drive according to claim 1, characterized in that, The correction actuator includes a base, a moving platform, a driving gear, a driven gear, a lead screw pair, and the target conveying roller. The moving platform, DC servo motor, driving gear, driven gear, and lead screw pair are all mounted on the base. The output shaft of the DC servo motor is fixedly connected to the driving gear. The driving gear meshes with the driven gear. The driven gear is fixedly connected to the drive end of the lead screw of the lead screw pair. The nut of the lead screw pair is fixedly connected to the moving platform. The moving platform is slidably connected to the top surface of the base via a slide rail. The target conveying roller is rotatably mounted on the moving platform.

5. The web guiding system based on DC servo drive as described in claim 4, characterized in that, The step of generating a PWM drive control signal for controlling the operation of the servo drive module based on the position offset signal detected by the offset detection module includes: The rotation direction and the number of revolutions required for the DC servo motor are calculated based on the position offset signal detected by the offset detection module and the transmission ratio between the drive gear and the transmission gear. The number of Hall pulses required to drive the DC servo motor is calculated based on the calculated number of rotations required by the DC servo motor and the number of Hall pulses required for one rotation of the DC servo motor. The PWM drive control signal is generated based on the calculated number of Hall pulses required to drive the DC servo motor and the rotation direction of the DC servo motor.

6. The web web guiding system based on DC servo drive according to any one of claims 1-5, characterized in that, The rotary encoder is a 1000-line magnetic encoder or a 2500-line magnetic encoder.

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