An automatic adaptive control system for flow of electronic belt scale

Abstract

The present invention provides an automatic adaptive control system for flow of an electronic belt scale, comprising: an inlet material belt conveyor, an electronic belt scale and an outlet material belt conveyor; the inlet material belt conveyor conveys front-end processed materials to the electronic belt scale, and transmits them to the rear-end outlet material belt conveyor after weighing and metering; wherein the electronic belt scale comprises a scale body belt, a control system, a belt drive motor and a belt speed sensor, the belt drive motor drives the scale body belt under the control of the control system, and the belt speed sensor detects the real-time speed of the scale body belt; the controller adjusts the control of the belt drive motor according to the comparison result of the real-time speed of the scale body belt detected by the belt speed sensor and the preset reference belt speed control value, so as to change the driving of the scale body belt by the belt drive motor.

Description

Technical Field

[0001] The invention relates to the field of flow measurement control, and in particular to an automatic adaptive control system for flow of an electronic belt scale. Background Art

[0002] In the industrial processing of bulk materials, electronic belt scales are often used to measure the weight of materials. Electronic belt scales are divided into two operating modes: metering and control. If there is no material buffer device (such as a feeder or metering tube) at the front end, the electronic belt scale can only operate in metering mode and only measure the weight of the material passing through.

[0003] This application is used in specific process flow, such as weight measurement of tobacco after drying. The instantaneous material flow fluctuation is relatively large, which will have three effects in production:

[0004] 1. The scale cannot meet the stable flow control requirements of the backend;

[0005] 2. When the incoming material flow fluctuates greatly, it affects the measurement accuracy of the electronic scale;

[0006] 3. If the operation is in control mode, it is difficult to accurately set the control flow target value, and there is a risk of material blockage during transportation. Summary of the invention

[0007] The technical problem to be solved by the present invention is to provide an automatic adaptive control system for the flow of an electronic belt scale in view of the above-mentioned defects in the prior art, which detects and calculates the speed value of the scale belt and uses it as a reference for adjusting the flow control target value. The use of this system does not require additional hardware facilities to be added or modified, and can solve the problems existing in the prior art by further logical operations and associations on its own detection data.

[0008] According to the present invention, an automatic adaptive control system for flow of an electronic belt scale is provided, comprising: an inlet material belt conveyor, an electronic belt scale and an outlet material belt conveyor; the inlet material belt conveyor conveys the front-end processed material to the electronic belt scale, and transmits it to the rear-end outlet material belt conveyor after weighing and metering; wherein the electronic belt scale comprises a scale belt, a control system, a belt drive motor and a belt speed sensor, the belt drive motor drives the scale belt under the control of the control system, and the belt speed sensor detects the real-time speed of the scale belt; the controller adjusts the control of the belt drive motor according to the comparison result of the real-time speed of the scale belt detected by the belt speed sensor and the preset reference belt speed control value, so as to change the drive of the scale belt by the belt drive motor.

[0009] In a preferred embodiment, the controller enables the belt drive motor to reduce the driving of the scale body belt when the real-time speed value minus the reference belt speed control value exceeds a first predetermined threshold.

[0010] In a preferred embodiment, the controller enables the belt drive motor to increase the drive on the scale belt when the reference belt speed control value minus the real-time speed value exceeds a second predetermined threshold.

[0011] In a preferred embodiment, the controller does not change the drive of the belt drive motor on the scale belt when the real-time speed value minus the reference belt speed control value does not exceed the first predetermined threshold and the reference belt speed control value minus the real-time speed value does not exceed the second predetermined threshold.

[0012] In a preferred embodiment, the controller performs a comparison deviation operation on the real-time speed value and the reference belt speed control value.

[0013] In a further preferred embodiment, the controller uses PID calculation to perform a comparison deviation operation between the real-time speed value and the reference belt speed control value.

[0014] In a further preferred embodiment, the controller uses a step-by-step difference comparison calculation to perform a deviation operation on the real-time speed value and the reference belt speed control value.

[0015] In a preferred embodiment, the inlet material belt conveyor conveys the front-end processed material to the electronic belt scale at a constant speed.

[0016] In a preferred embodiment, the electronic belt scale flow automatic adaptation control system is used when the front end of the electronic belt scale is not equipped with a material buffer device.

[0017] In a preferred embodiment, the electronic belt scale flow automatic adaptation control system is used in tobacco processing.

[0018] The material flow rate can be controlled by monitoring and calculating the belt speed of the electronic belt scale. This can be applied to the metering control of electronic belt scales on production lines that are not equipped with material buffer devices at the front end. The belt speed of the electronic belt scale is used as the basis for adjusting the flow control target value, so that the flow control target value and the actual material transportation situation can be automatically adapted. The electronic belt scale operates in flow control mode to achieve stable flow control. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] A more complete understanding of the present invention and its attendant advantages and features will be more readily appreciated by reference to the following detailed description taken in conjunction with the accompanying drawings, in which:

[0020] Figure 1 The structure diagram of the automatic adaptive control system for electronic belt scale flow according to the preferred embodiment of the present invention is schematically shown.

[0021] Figure 2 A control flow chart of an automatic adaptive control system for an electronic belt scale flow according to a preferred embodiment of the present invention is schematically shown.

[0022] Description of the drawings: 1-inlet material belt conveyor; 2-electronic belt scale; 3-exit material belt conveyor; 4-scale belt; 5-control system; 6-belt drive motor; 7-belt speed sensor.

[0023] It should be noted that the drawings are used to illustrate the present invention, rather than to limit the present invention. Note that the drawings showing the structures may not be drawn to scale. In addition, in the drawings, the same or similar elements are marked with the same or similar reference numerals. DETAILED DESCRIPTION

[0024] In order to make the contents of the present invention clearer and easier to understand, the contents of the present invention are described in detail below in conjunction with specific embodiments and drawings.

[0025] Figure 1 The structure diagram of the automatic adaptive control system for electronic belt scale flow according to the preferred embodiment of the present invention is schematically shown.

[0026] like Figure 1 As shown, the electronic belt scale flow automatic adaptive control system according to the preferred embodiment of the present invention includes: an inlet material belt conveyor 1, an electronic belt scale 2 and an outlet material belt conveyor 3.

[0027] The inlet material belt conveyor 1 (generally at a constant speed) transports the front-end processed materials to the electronic belt scale 2, and after weighing and metering, it is transmitted to the rear-end outlet material belt conveyor 3 so that the materials can be transported to subsequent processing equipment.

[0028] Among them, the electronic belt scale 2 includes a scale belt 4, a control system 5, a belt drive motor 6 and a belt speed sensor 7. The belt drive motor 6 drives the scale belt 4 under the control of the control system 5, and the belt speed sensor 7 detects the real-time speed of the scale belt 4.

[0029] The controller adjusts the control of the belt drive motor 6 according to the comparison result of the real-time speed of the scale belt 4 detected by the belt speed sensor 7 and the preset reference belt speed control value to change the drive of the belt drive motor 6 on the scale belt 4.

[0030] Specifically, preferably, for example, when the real-time speed value minus the reference belt speed control value exceeds a first predetermined threshold value, the controller causes the belt drive motor 6 to reduce the drive on the scale belt 4; when the reference belt speed control value minus the real-time speed value exceeds a second predetermined threshold value, the controller causes the belt drive motor 6 to increase the drive on the scale belt 4.

[0031] Moreover, preferably, the controller does not change the drive of the belt drive motor 6 on the scale belt 4 when the real-time speed value minus the reference belt speed control value does not exceed the first predetermined threshold and the reference belt speed control value minus the real-time speed value does not exceed the second predetermined threshold.

[0032] If the belt speed is too fast, the target flow value is judged to be too high, and the system adjusts the target flow value down, otherwise it will be increased. The system sets a control dead zone, and does not adjust the target flow value within a certain range when the belt speed is close to the target speed.

[0033] The basic principle of electronic belt scale measurement is to calculate the weight signal of the weight sensor and the speed signal of the conveyor belt by integrating the values ​​to obtain the instantaneous flow value and the cumulative value. If the electronic belt scale needs to achieve constant flow control of materials, the weighing system must suppress the influence of material weight fluctuations by continuously adjusting the belt speed according to the deviation between the instantaneous flow value and the set flow value. Therefore, in turn, the belt speed can also be used as a reference for the change in the incoming material weight.

[0034] Set an ideal belt speed control value (reference belt speed control value) in the control system, and use the real-time belt speed to compare with the set value for deviation calculation. The calculation method can be PID (Proportion Integration Differentiation) calculation or step-by-step difference comparison calculation to determine the matching degree of the flow control target value. The calculated value is used as the basis for adjusting the flow control target value. By monitoring the belt speed throughout the production process and adjusting the real-time flow control target value, the automatic adaptation of the flow control target value is achieved, and the electronic belt scale can operate in control mode.

[0035] In a production environment where the standard deviation of material flow is 130 to 180, after applying the control method, the standard deviation of flow can be reduced to 20 to 30. The present invention is based on the original hardware, and optimizes the adaptation of flow control by modifying the control program, which saves the equipment modification cost, has the characteristics of high reliability and short implementation period.

[0036] Figure 2 A control flow chart of an automatic adaptive control system for an electronic belt scale flow according to a preferred embodiment of the present invention is schematically shown.

[0037] At the initial stage of production, the control system operates in the head material processing mode, and the electronic belt scale controls and measures at a fixed target flow value, which is only required to prevent the electronic belt scale from being blocked at the inlet.

[0038] After the flow enters a relatively stable state, the control system enters the flow adaptation control mode. The system monitors the speed of the scale belt 4 in real time, and determines whether the set target value of the flow is appropriate by comparing it with the belt speed target value, and then adjusts the flow control target value. If the belt speed is too fast, it is judged that the target flow value is too high, and the system lowers the target flow value, otherwise it will increase it. The system sets a control dead zone, and within a certain range where the belt speed is close to the target speed, the target flow value will not be adjusted. Through the above-mentioned logical control, the electronic belt scale has the function of automatic adaptation of flow control, and realizes the operation of the electronic belt scale in control mode, thereby improving the stability of material flow and providing guarantee for the next processing step.

[0039] In actual application, relevant parameters such as material head section processing time, material head section set flow rate, belt speed control target value, comparison operation response parameter, control dead zone, set value adjustment frequency and amplitude need to be adjusted according to the actual application environment.

[0040] The present invention designs an electronic belt scale, which can realize the operation in flow control mode in an environment where the front end of the electronic belt scale is not equipped with a material buffer device, and the control target flow can be automatically adapted to the stable flow control system. The control system detects the belt speed value of the scale body, identifies the surplus degree of the material transported from the front end, and then adjusts the set flow of the scale to adapt, so as to achieve the purpose of stable flow control. The control system can be realized only by writing a control system program, and has the advantages of low cost, strong practicality, and wide application fields.

[0041] Specifically, for example, the electronic belt scale flow automatic adaptation control system of the present invention can be applied to the electronic belt scale without a material buffer device at the front end, and is used for flow metering control in the industrial processing and production process of bulk materials that have certain requirements on the material conveying flow stability. And for example, the electronic belt scale flow automatic adaptation control system of the present invention is used in tobacco processing.

[0042] It should be noted that, unless otherwise specified, the terms "first", "second", "third", etc. in the specification are only used to distinguish the various components, elements, steps, etc. in the specification, and are not used to indicate the logical relationship or sequential relationship between the various components, elements, steps, etc.

[0043] It is to be understood that, although the present invention has been disclosed as a preferred embodiment, the above embodiment is not intended to limit the present invention. For any person skilled in the art, without departing from the scope of the technical solution of the present invention, the technical content disclosed above can be used to make many possible changes and modifications to the technical solution of the present invention, or modified into equivalent embodiments of equivalent changes. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the scope of protection of the technical solution of the present invention.

Claims

1. An automatic adaptive control system for flow of an electronic belt scale, characterized in that: The electronic belt scale flow automatic adaptation control system comprises: an inlet material belt conveyor, an electronic belt scale and an outlet material belt conveyor; the inlet material belt conveyor conveys the front-end processed material to the electronic belt scale, and transmits it to the rear-end outlet material belt conveyor after weighing and metering; wherein the electronic belt scale comprises a scale belt, a control system, a belt drive motor and a belt speed sensor, the belt drive motor drives the scale belt under the control of the control system, and the belt speed sensor detects the real-time speed of the scale belt; the controller adjusts the control of the belt drive motor according to the comparison result of the real-time speed of the scale belt detected by the belt speed sensor and the preset reference belt speed control value, so as to change the drive of the scale belt by the belt drive motor; When the real-time speed value minus the reference belt speed control value exceeds a first predetermined threshold, the controller causes the belt drive motor to reduce the drive on the scale belt; when the reference belt speed control value minus the real-time speed value exceeds a second predetermined threshold, the controller causes the belt drive motor to increase the drive on the scale belt; The controller does not change the driving of the belt drive motor on the scale belt when the real-time speed value minus the reference belt speed control value does not exceed the first predetermined threshold value, and the reference belt speed control value minus the real-time speed value does not exceed the second predetermined threshold value; The controller performs a comparison deviation operation between the real-time speed value and the reference belt speed control value; After the flow enters a relatively stable state, the control system enters the flow adaptation control mode; the system monitors the speed of the scale belt in real time, and determines whether the set target value of the flow is appropriate by comparing it with the belt speed target value, and then adjusts the flow control target value.

2. The electronic belt scale flow automatic adaptive control system according to claim 1 is characterized in that: The controller uses PID calculation to compare the real-time speed value with the reference belt speed control value.

3. The automatic adaptive control system for electronic belt scale flow according to claim 1 is characterized in that: The controller uses a step-by-step difference comparison calculation to perform a deviation operation on the real-time speed value and the reference belt speed control value.

4. The electronic belt scale flow automatic adaptation control system according to claim 1, characterized in that: The inlet material belt conveyor conveys the front-end processed materials to the electronic belt scale at a constant speed.

5. The electronic belt scale flow automatic adaptive control system according to claim 1, characterized in that: The electronic belt scale flow automatic adaptation control system is used for an electronic belt scale whose front end is not equipped with a material buffer device.

6. The electronic belt scale flow automatic adaptive control system according to claim 1, characterized in that: The electronic belt scale flow automatic adaptation control system is used for tobacco processing.

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