Servo paper feeding control system based on ethercat control bus

Abstract

The invention relates to the technical field of paper feeding equipment control systems, and discloses a servo paper feeding control system based on an ethercat control bus, which comprises a servo control unit, an encoder acquisition port is integrated on the servo control unit, the encoder acquisition port is in butt joint with various encoders, and a control instruction is sent to the servo control unit through the encoders; the position monitoring unit is used for monitoring the progress position of the paperboard on each conveying roller in unit time and sending the position information to the judging unit; the judgment unit is used for calculating the inlet and outlet quantity of the paperboards in unit time, calculating the difference value of the inlet and outlet quantity of the paperboards on the adjacent conveying rollers and sending difference value information to the servo control unit; and the speed regulation and control unit is used for regulating the rotating speed of each conveying roller according to the control instruction sent by the servo control unit. The problems that existing paper feeding equipment cannot be in butt joint with various encoders, universality is low, paper feeding precision is not high, and timeliness and synchronism are difficult to guarantee are solved.

Description

Technical Field

[0001] The invention relates to the technical field of paper feeding equipment control systems, and in particular to a servo paper feeding control system based on an ethercat control bus. Background Art

[0002] Currently, paper feeding equipment plays a vital role in the field of industrial automation, especially in the printing, packaging and papermaking industries. However, since the encoder interface of current paper feeding equipment is not compatible with multiple types of encoders, it is difficult to connect existing equipment. This limitation requires users to configure dedicated controllers for different types of encoders, which not only increases the cumbersomeness of equipment use, but also reduces the versatility and flexibility of the equipment. For the need to process cardboards of different sizes and materials, this processing equipment undoubtedly adds additional costs and operational difficulties.

[0003] Secondly, during the paper feeding process, traditional paper feeding equipment can only use dedicated controllers, resulting in a lack of synchronous control mechanism for the roller shaft. After long-term use of the paper feeding equipment, the roller shaft will be worn and form uncontrollable differences, resulting in the speed and position of each cardboard being difficult to maintain consistency during the paper feeding process, making it impossible to achieve precise synchronous control and ensure the timeliness and synchronization of paper feeding. This not only increases the difficulty of equipment debugging and maintenance, but also limits the application of equipment in high-speed, high-precision production environments.

[0004] Therefore, the existing paper feeding equipment can only be equipped with a dedicated controller, which cannot guarantee the timeliness and synchronization of the paper feeding process. Now it is necessary to provide a servo paper feeding control system based on the ethercat control bus. Summary of the invention

[0005] The present invention aims to provide a servo paper feeding control system based on the ethercat control bus to solve the problems that the existing paper feeding equipment cannot be connected to a variety of encoders, has low versatility, has low paper feeding accuracy, and is difficult to ensure timeliness and synchronization.

[0006] In order to achieve the above object, the present invention adopts the following technical scheme:

[0007] The present invention is used to provide a system that can achieve docking of multiple encoders, improve versatility, and can control the rotation speed and stop time of each transmission roller one by one according to the input and output volume, so as to ensure the synchronization and timeliness of paper feeding one by one and improve paper feeding efficiency. Specifically, it is a servo paper feeding control system based on ethercat control bus, which specifically includes a servo control unit, and an encoder acquisition port is integrated on the servo control unit. The encoder acquisition port is docked with multiple encoders, and control instructions are sent to the servo control unit through the encoder;

[0008] A position monitoring unit is used to monitor the process position of the paperboard on each conveying roller within a unit time and send the position information to the determination unit;

[0009] A determination unit, used to calculate the amount of cardboard in and out per unit time according to the received position information of the cardboard on each conveying roller, calculate the difference in the amount of cardboard in and out on adjacent conveying rollers, and send the difference information to the servo control unit;

[0010] The servo control unit is also used to send a control instruction to the speed control unit according to the difference information;

[0011] The speed control unit is used to monitor the rotation speed of each conveying roller in real time and send the speed information to the servo control unit; it is also used to adjust the rotation speed of each conveying roller according to the control instructions sent by the servo control unit.

[0012] The principles and advantages of this solution are:

[0013] In the prior art, since the controller of the paper feeding device is connected to a dedicated encoder, different encoders need to be configured and debugged for different sizes and specifications of paperboards, which is cumbersome and increases the workload. The control system is not flexible enough and has low versatility due to the limitation of the dedicated encoder. When the paper feeding device is used for a long time, the rollers are easily affected by wear and tear, resulting in different rotation speeds between the rollers, asynchronous paper feeding, untimely paper feeding, etc., resulting in production errors and even product scrapping.

[0014] This solution first uses the ethercat control bus and integrates a high-speed encoder acquisition port, so that the paper feeding control system can connect to multiple encoders, realize the connection of multiple encoders, and realize the adjustment and control of cardboards of different specifications and sizes by connecting encoders, without the need to specially replace paper feeding equipment, greatly reducing production costs, while improving the versatility and flexibility of paper feeding equipment. At the same time, the encoder can be used to adjust the rotation speed of each conveying roller to ensure the consistency of each conveying roller. By real-time monitoring of the position of the paper, the input and output volume of the cardboard can be obtained, and then the transmission time of the cardboard can be predicted. According to the input and output volume, the rotation speed and stop time of each conveying roller are controlled one by one to ensure the synchronization of each paper transmission, ensure the continuity and stability of paper transmission, and improve the overall paper feeding efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural diagram of embodiment 1 of the present invention.

[0016] Figure 2 This is a schematic diagram of position monitoring according to Embodiment 1 of the present invention.

[0017] Figure 3This is a schematic diagram of the structure of the second embodiment of the present invention. DETAILED DESCRIPTION

[0018] The following is further described in detail through specific implementation methods:

[0019] Embodiment 1

[0020] Basically as attached Figure 1 As shown: the servo paper feeding control system based on the ethercat control bus integrates a high-speed encoder acquisition port based on the ethercat control bus, so that the paper feeding control system can connect to a variety of encoders, realize the connection of a variety of encoders, improve the versatility and flexibility of the paper feeding control system, and at the same time, by obtaining the paper in and out volume during the paper feeding process, control the rotation speed and stop time of each conveying roller one by one to ensure the synchronization and timeliness of the paper. Specifically, it includes a servo control unit integrated on the paper feeding device, and a high-speed encoder acquisition port is integrated on the servo control unit based on the ethercat control bus. A variety of encoders can be connected through the encoder acquisition port. According to the specifications and sizes of the paper, it can adapt to the controllers of a variety of paper feeding devices. The encoder sends control instructions to the servo control unit to complete the control without replacing the equipment separately, improving the versatility, making the operation simpler and more flexible, and realizing intelligent control.

[0021] The position monitoring unit is used to monitor the process position of the paperboard on each conveying roller within a unit time and send the position information to the determination unit. In this embodiment, the conveying rollers are n rollers installed side by side in the paper feeding device, where 1≤n≤6. In this embodiment, as shown in the attached Figure 2 As shown in the figure, four rollers are used as an example. The first roller is the one on the outermost side of the paper feeding device inlet, and the second roller, the third roller, the fourth roller, and the nth roller are arranged in the paper feeding direction. The nth roller is the last roller close to the processing position. The position monitoring unit monitors the process position of the paper in real time to obtain the relative position of the paper on each conveying roller. The position monitoring unit sends the obtained position information of each conveying roller to the determination unit.

[0022] In this embodiment, the process position of the paper within a unit time T is monitored, such as monitoring the initial position of the paperboard on the top of the roller at time T0, recorded as S0, and then monitoring the position of the paperboard on the top of the same conveying roller at time T1, recorded as S1. In this embodiment, the position monitoring unit can be installed by a position sensor or other device.

[0023] The determination unit is used to calculate the amount of cardboard in and out per unit time according to the received position information of the cardboard on each conveying roller, and calculate the difference of the amount of cardboard in and out on adjacent conveying rollers, and send the difference information to the servo control unit.

[0024] Monitor the amount of cardboard in and out Q on the nth roller within a unit time Tn , through the acquired location information, we get Q n = S1-S0. In this way, the inlet and outlet volume of each conveying roller are obtained respectively, and Q is obtained respectively. 1、 Q 2、 Q 3、 Q4, calculate the difference E of the in-and-out amounts of adjacent conveying rollers in sequence according to the in-and-out amounts, such as E1=Q2-Q1, E2=Q3-Q2, E3=Q4-Q3.

[0025] The calculated difference E is judged, and the rotation speed of the conveying roller is adjusted according to the judgment result. In this embodiment, when E>0, it means that the rotation speed of the nth roller of the former is faster than the rotation speed of the n-1th roller of the latter. At this time, in order to ensure the paper feeding efficiency and the synchronization between the conveying rollers, the servo control unit sends a control instruction to the speed control unit to adjust the rotation speed of the n-1th conveying roller to be consistent with the rotation speed of the nth conveying roller; when E<0, it means that the rotation speed of the nth roller of the former is slower than the rotation speed of the n-1th roller of the latter, and the rotation speed of the nth conveying roller is adjusted to be consistent with the rotation speed of the n-1th roller of the latter. Therefore, the rotation speed of each conveying roller is analyzed and adjusted one by one according to the difference, ensuring that the rotation speed of each conveying roller is consistent, ensuring the stability of paper transmission, and being more conducive to accurately predicting the paper transmission time, while improving the transmission efficiency.

[0026] The speed control unit is used to monitor the rotation speed of each conveyor roller in real time and send the speed information to the servo control unit. The servo control unit determines the current running state of the conveyor roller according to the speed information to ensure that the rotation speed of the conveyor roller is consistent. At the same time, the speed control unit is also used to adjust the rotation speed of each conveyor roller according to the control instructions sent by the servo control unit to ensure the consistency of the rotation frequency.

[0027] In this embodiment, the speed control unit also controls the rotation speed and stop time of each conveying roller according to the obtained cardboard in-and-out volume. First, according to the overall length of the cardboard and the cardboard in-and-out volume, the real-time position of the cardboard on each conveying roller is monitored, and the conveying time of the cardboard on each conveying roller can be calculated by setting the rotation speed of the conveying roller. When the conveying time of the cardboard on the conveying roller is less than 2s, it means that the cardboard is about to be conveyed on the conveying roller. At this time, the rotation speed of the conveying roller will be reduced until the rotation speed is 0, so as to gradually stop the rotation of the conveying roller, so as to avoid the conveying roller from idling during the conveying process, causing unnecessary wear and waste of resources, and also avoid cardboard transmission congestion, which affects orderly processing.

[0028] When the next cardboard needs to be conveyed continuously, the position monitoring unit monitors the position of the end of the previous cardboard in real time. When the end of the previous cardboard begins to leave the second conveying roller, the speed control unit controls the first conveying roller to start accelerating to a consistent rotation speed to convey the next cardboard, thereby ensuring the transmission efficiency between each cardboard, shortening the waiting gap between cardboards, and ensuring that there is sufficient operating gap between each cardboard to avoid stacking conflicts.

[0029] In this embodiment, a high-speed encoder acquisition port is integrated through the ethercat control bus, so that the paper feeding control system can connect to multiple encoders and realize the connection of multiple encoders. Therefore, according to the docked encoder, it can be applied to paper feeding equipment of different sizes and specifications, improving the versatility and flexibility of the paper feeding system. At the same time, the rotation speed of each conveying roller and the amount of paperboard in and out can be monitored in real time through the adapted multiple encoders, and the rotation speed of each conveying roller can be adjusted one by one according to the amount of paperboard in and out, to ensure the consistency of the rotation speed of each conveying roller, thereby ensuring the synchronization and orderliness of paperboard transmission, and ensuring the stability and timeliness of paperboard transmission.

[0030] Embodiment 2

[0031] Different from the first embodiment, as shown in the attached Figure 3 As shown, in this embodiment, a load evaluation unit is also included, through which the real-time load status of each conveying roller is evaluated. When the load of the conveying roller exceeds the set threshold, the speed control unit will reduce the rotation speed of the corresponding conveying roller, and synchronously adjust the speed of other conveying rollers to make the conveying consistent. In this way, when the paper feeding equipment is in a state of long-term high-load operation, the operating load can be appropriately reduced, or the operation can be stopped for a certain period of time to avoid overload operation of the equipment, ensure the stability and safety of the equipment, and avoid the situation that excessive load of the equipment may cause overheating of the roller shaft and increased wear.

[0032] In this embodiment, the load state is the continuous operation time, surface temperature, and wear state of the conveyor roller. In this embodiment, the continuous operation time is determined based on the standby time obtained by the control system. The surface temperature is the temperature of the conveyor roller, which can be detected by a temperature sensor. When the temperature is higher than the normal production temperature, heat dissipation treatment is required. The internal temperature of the equipment is reduced by reducing the rotation speed or stopping the operation to ensure the safe operation of the equipment. The wear state can be detected by ultrasonic wave. The speed and reflection of ultrasonic wave propagation in the material can detect cracks, deformation, etc. inside the roller. Or it can be evaluated through production data. By analyzing the cardboard inlet and outlet volume, operation time and other data on the production line, combined with the design life and performance parameters of the roller, the wear condition of the roller can be indirectly evaluated. The specific monitoring method is not limited in this scheme.

[0033] In this embodiment, the rotation speed of the conveying roller is further controlled by the load evaluation unit to ensure the transmission efficiency of the paper feeding equipment while ensuring the safety and stability of the equipment operation. The rotation speed of the conveying roller is controlled in real time in combination with the operating status, so as to continuously optimize the control method, improve production efficiency and equipment utilization. This solution can realize the control of the rotation speed of each conveying roller, which is to be able to connect to a variety of encoders and control them according to actual production needs, so as to achieve the effect of successive regulation and control, ensure the synchronization and timeliness of paper feeding, and improve production safety.

[0034] The above is only an embodiment of the present invention, and the common knowledge such as the known specific technical solutions and / or characteristics in the solution is not described in detail here. It should be pointed out that for those skilled in the art, without departing from the technical solution of the present invention, several modifications and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A servo paper feeding control system based on ethercat control bus, characterized by: It includes a servo control unit, which is integrated with an encoder acquisition port, the encoder acquisition port is connected to a variety of encoders, and a control instruction is sent to the servo control unit through the encoder; A position monitoring unit is used to monitor the process position of the paperboard on each conveying roller within a unit time and send the position information to the determination unit; A determination unit, used to calculate the amount of cardboard in and out per unit time according to the received position information of the cardboard on each conveying roller, calculate the difference in the amount of cardboard in and out on adjacent conveying rollers, and send the difference information to the servo control unit; The servo control unit is also used to send a control instruction to the speed control unit according to the difference information; The speed control unit is used to monitor the rotation speed of each conveying roller in real time and send the speed information to the servo control unit; it is also used to adjust the rotation speed of each conveying roller according to the control instructions sent by the servo control unit.

2. The servo paper feeding control system based on ethercat control bus according to claim 1 is characterized in that: The conveying rollers include n roller shafts arranged side by side, 1≤n≤6; the paperboard is conveyed from the inlet end to the processing position through each conveying roller in sequence.

3. The servo paper feeding control system based on ethercat control bus according to claim 2 is characterized in that: The amount of cardboard in and out per unit time on the nth conveyor roller Q n =S1-S0, where S1 is the position of the cardboard on the top of the conveying roller at time T1, and S0 is the initial position of the cardboard on the top of the same conveying roller at time T0.

4. The servo paper feeding control system based on ethercat control bus according to claim 3 is characterized in that: The difference in the amount of adjacent conveyor rollers is E = Q n -Q n-1 ; Adjust the rotation speed of the conveying roller according to the difference. When E>0, adjust the rotation speed of the n-1th conveying roller. When E<0, adjust the rotation speed of the nth conveying roller.

5. The servo paper feeding control system based on ethercat control bus according to claim 3 is characterized in that: According to the cardboard inlet and outlet volume Q of each conveying roller n , and adjust the rotation speed and stop time of each conveying roller respectively.

6. The servo paper feeding control system based on ethercat control bus according to claim 5, characterized in that: According to the acquired input and output volume, the real-time position of the cardboard on each conveyor roller is monitored, and the conveying time of the cardboard on the conveyor roller is calculated by the rotation speed of the conveyor roller. When the conveying time is less than 2s, the conveyor roller is controlled to slow down until it stops.

7. The servo paper feeding control system based on ethercat control bus according to claim 1, characterized in that: It also includes a load evaluation unit for evaluating the real-time load status of the conveying roller; when the load of the conveying roller exceeds a set threshold, the speed control unit will reduce the rotation speed of the conveying roller.

8. The servo paper feeding control system based on ethercat control bus according to claim 7 is characterized in that: The load state is the continuous operation time, surface temperature and wear state of the conveying roller.

9. The servo paper feeding control system based on ethercat control bus according to claim 6, characterized in that: The position monitoring unit is also used to monitor the position of each cardboard being continuously transported; the speed control unit is also used to respectively control the stopping speed and starting speed of the transport roller according to the monitored cardboard position.

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