An Adaptive Quantitative Measurement and Control Method

Abstract

This invention relates to an adaptive quantitative measurement control method, comprising the following steps: setting parameters; starting the instrument, beginning measurement, and entering fast-increasing output; upon reaching the set fast-increasing time, closing the fast-increasing output and entering slow-increasing output, and recording the start time; after reaching the slow-increasing prohibition comparison time, determining when to stop the slow-increasing output; after stopping the slow-increasing output, recording the time consumed throughout the entire slow-increasing output process and recording the current actual measured weight; entering correction mode; after completing the correction mode, returning to the start measurement stage to perform the next package measurement. This invention, by setting the fast-increasing time to control the fast-increasing output stage, can double the fast-increasing output speed, thereby increasing the quantitative measurement speed. By changing the control algorithm corresponding to the fast and slow-increasing stages, it improves the speed and accuracy of quantitative packaging and achieves efficient and stable adaptive correction, effectively solving the impact of density and flowability changes on quantitative measurement.

Description

Technical Field

[0001] This invention relates to the field of weighing quantitative control technology, and in particular to an adaptive quantitative measurement control method. Background Technology

[0002] Metering and quantitative control equipment is a type of mechanical device used in industries such as batching and packaging to control the weight of materials. The accuracy and speed of this type of equipment are core methods for ensuring product quality and efficiency for customers. In actual use, the ease of debugging and maintenance is also an important factor for customers. Currently, traditional quantitative metering technologies have the following problems:

[0003] (i) In the existing batching and packaging industry, the quantitative measurement process is prone to inaccurate measurement due to different on-site use environment, material characteristics or different formulas. Traditional quantitative measurement instruments are difficult to meet customers' requirements for the speed and accuracy of the equipment.

[0004] (ii) Conventional metering and quantitative instruments all use weight judgment to determine when to stop the rapid feed output. Due to the drop and filtering time, there is a certain time difference between the weight read by the instrument and the actual weight of the material falling into the weighing hopper. As a result, the rapid feed output speed cannot be too fast or too slow. Too fast will easily cause overshoot, and too slow will affect the speed.

[0005] (III) Traditional metering and quantitative instruments all use real-time weight comparison to switch between fast, medium, and slow addition for measurement. The main parameters to be set are fast addition amount, medium addition amount, slow addition amount, advance amount, fast prohibition comparison time, medium prohibition comparison time, slow prohibition comparison time, and filter coefficient. Since any adjustment of any parameter requires adjustment of the corresponding other parameters, if the user frequently switches materials, the parameters need to be adjusted frequently, which can easily lead to complicated and difficult debugging, especially on high-speed and high-precision equipment. Summary of the Invention

[0006] In view of the shortcomings of the prior art, the purpose of this invention is to provide an adaptive quantitative measurement and control method to solve one or more problems in the prior art.

[0007] To achieve the above objectives, the technical solution of the present invention is as follows:

[0008] An adaptive quantitative measurement and control method includes the following steps:

[0009] Set parameters;

[0010] Start the instrument, begin measurement, and enter rapid output mode;

[0011] Once the set fast acceleration time is reached, the fast acceleration output is turned off and the slow acceleration output is switched on, and the start time is recorded.

[0012] After the slow-increase prohibition comparison time is reached, determine when to stop the slow-increase output;

[0013] After stopping the slow feed output, record the time taken for the entire slow feed output process and the current actual measured weight;

[0014] Enter correction mode;

[0015] After the correction mode is completed, return to the start metering stage to perform the next package metering.

[0016] Furthermore, the parameters include: fast addition time, slow prohibition comparison time, and air time.

[0017] Furthermore, the specific steps of the process for determining to stop the slow increase output include the following:

[0018] Real-time calculation of current traffic;

[0019] Real-time calculation of air volume;

[0020] Determine whether the condition for stopping the slow increase in output has been met.

[0021] Furthermore, the real-time current traffic is calculated using the following formula:

[0022] Real-time flow = Δ weight / Δ time

[0023] Where current flow rate represents the flow rate of material during slow feed output, Δ weight represents the real-time weight within the flow calculation time period, and Δ time represents the flow calculation time period.

[0024] Furthermore, the real-time air quantity is calculated according to the following formula:

[0025] Airborne volume = Current flow rate × Airborne time

[0026] The "air quantity" refers to the weight of the material when it leaves the feeding device and is still in mid-air before finally falling into the weighing hopper at the moment the slow feed output ends, and the "air time" refers to the time it takes for the material to leave the feeding device and fall into the weighing hopper at the moment the feed output ends.

[0027] Furthermore, the conditions for stopping the slow increase output are as follows:

[0028] If the current weight is greater than or equal to the target weight minus the air weight, stop the slow increase output; if the current weight is less than the target weight minus the air weight, continue to increase the output until the target weight is reached.

[0029] Furthermore, the correction mode includes the following steps:

[0030] Correct the fast-addition time;

[0031] Correcting time errors in flight.

[0032] Furthermore, the correction mode includes the following steps:

[0033] The fast acceleration time correction is calculated using the following formula:

[0034] New fast-addition time = Old fast-addition time + (Actual slow-addition time - Slow-addition planned time) × Adjustment ratio

[0035] Wherein, the new fast addition time represents the output time of the fast addition stage after correction, the old fast addition time represents the output time of the fast addition stage before correction, the actual slow addition time represents the time spent in the actual slow addition stage, and the slow addition planned time represents the time spent in the planned target slow addition stage.

[0036] The in-flight time correction is calculated using the following formula:

[0037] New air time = Old air time + (Measured weight - Target quantity) × Correction ratio

[0038] The new air time represents the time it takes for the material to fall from the air into the weighing hopper after the correction, which is the time used for the new air quantity. The old air time represents the time it took for the material to fall from the air into the weighing hopper before the correction, which is the time used for the old air quantity. The target quantity represents the set target weight. The actual measured weight represents the weight that is waiting for the weight in the weighing hopper to stabilize and enter the fixed value record.

[0039] Furthermore, the time-of-flight correction process also includes the following steps:

[0040] Determine if the target quantity has changed; if the target quantity has changed, enter continuous correction mode.

[0041] If the target quantity remains unchanged, enter the discontinuous correction mode.

[0042] Furthermore, the continuous correction mode includes the following steps:

[0043] Detect the quantity of each package and execute the correction mode;

[0044] In correction mode, check whether the new air time is within the set air time range. If it exceeds the set air time range, return to the previous step. If it does not exceed the set air time range, execute discontinuous correction mode.

[0045] The discontinuous correction mode includes the following steps:

[0046] Get the quantity of weighed packages;

[0047] Based on the number of weighed packages obtained, determine whether the quantity is within the set quantity. If it does not exceed the set quantity, execute a correction mode.

[0048] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0049] (I) The adaptive quantitative metering control method provided by this invention adjusts the number of parameters from the traditional quantitative metering process's fast increment, medium increment, slow increment, advance, fast prohibition comparison time, medium prohibition comparison time, slow prohibition comparison time, and filter coefficient to fast increment time, slow prohibition comparison time, and idle time. This reduces the complexity of equipment debugging and simplifies the equipment operation process. By setting the slow prohibition comparison time, the impact caused by the shock force generated during the switch from fast increment output to slow increment output is avoided. At the same time, the fast increment time can be set to a short time to adapt to various operating conditions and has the advantage of easy adjustment.

[0050] (ii) Furthermore, by setting the fast addition time control for the fast addition output stage, the fast addition output speed can be doubled, thereby increasing the metering and quantitative speed. This does not affect the accuracy requirements of the slow addition output control, ensuring that the feeding will not overshoot when the fast addition output speed is increased.

[0051] (iii) Furthermore, during the slow-increase output stage, the real-time air volume is calculated in real time using the method of calculating real-time flow. The real-time air volume is used as the slow-increase stop criterion to control the slow-increase output to stop, thus ensuring accuracy.

[0052] (iv) Further, after the measurement is completed, the correction stage is entered. The fast addition time is corrected by the difference between the slow addition planned time and the slow addition actual time, so as to optimize the measurement speed. The air time error is corrected by the difference between the measured weight and the target amount. A continuous correction mode or a non-continuous correction mode is set so that the slow addition time finally meets the setting of the planned slow addition output time, so as to greatly improve the speed and accuracy of the quantitative measurement cycle.

[0053] (V) This invention improves the speed and accuracy of quantitative packaging by changing the control algorithm corresponding to the fast and slow stages, and achieves efficient and stable adaptive correction, which can effectively solve the impact of changes in density and flowability on quantitative measurement. Attached Figure Description

[0054] Figure 1 A flowchart of an adaptive quantitative measurement control method according to an embodiment of the present invention is shown. Detailed Implementation

[0055] To make the objectives, technical solutions, and advantages of this invention clearer, the adaptive quantitative measurement and control method proposed by this invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of this invention will become clearer from the following description. It should be noted that the accompanying drawings are in a very simplified form and use non-precise proportions, only for the purpose of conveniently and clearly illustrating the embodiments of this invention. Please refer to the accompanying drawings to make the objectives, features, and advantages of this invention more apparent and understandable. It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the implementation conditions of this invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportional relationships, or adjustments to the size, without affecting the effects and objectives achieved by this invention, should still fall within the scope of the technical content disclosed in this invention.

[0056] An adaptive quantitative measurement and control method, such as Figure 1 As shown, it includes the following steps:

[0057] Step S1: Set the core parameters as control parameters for the quantitative measurement stage.

[0058] The core parameters specifically include: fast acceleration time, slow comparison prohibition time, and air time. The number of parameters is reduced from eight in the traditional quantitative measurement process to three. The eight parameters are fast acceleration amount, medium acceleration amount, slow acceleration amount, lead time, fast comparison prohibition time, medium comparison prohibition time, slow comparison prohibition time, and filter coefficient. The three parameters are fast acceleration time, slow comparison prohibition time, and air time. The fast acceleration time and air time can initially be set to 0 to allow the system to adapt automatically, while the slow acceleration comparison prohibition time is generally set to 1 second to meet most operating conditions. This reduces the complexity of equipment debugging and simplifies the equipment operation process.

[0059] Step S2: After setting the core parameters, start the instrument and begin metering. Enter the fast feed output mode. The fast feed output mode specifically means that the discharge valve is at its maximum and the material flow rate is the fastest.

[0060] Step S3: After the set fast feeding time is reached, the fast feeding output is turned off and the slow feeding output is entered. The start time is recorded. The slow feeding output means that the discharge valve is at its minimum and the material flow rate is the slowest.

[0061] This invention allows for timed control of the fast acceleration output by setting a fast acceleration time, thereby preventing overshoot while increasing the block acceleration speed.

[0062] Since weighing is based on the conversion of force into weight, an impact force will be generated during the process of switching from fast increment output to slow increment output. In order to avoid the influence of this impact force, this invention avoids it by setting a comparison prohibition time.

[0063] Step S4: After the slow increment prohibition comparison time is reached, determine when to stop the slow increment output; specifically, the slow increment prohibition comparison time means that a certain period of time is started from the moment the fast increment output ends to determine when to stop the slow increment output. For example, if the slow increment prohibition time is set to 1 second, it means that 1 second is started from the moment the fast increment output ends to determine when to stop the slow increment output.

[0064] Specifically, the steps for determining to stop the slow increment output are as follows:

[0065] Step A1: During the slow addition process, the current flow rate is calculated in real time, specifically: Current flow rate = Δ weight / Δ time; where Δ time is the flow rate calculation time period, which can be set independently. In this embodiment, it is generally set to 0.2s-0.3s to ensure the speed and accuracy of the calculation, and Δ weight is the real-time weight within the flow rate calculation time period.

[0066] Of course, in other embodiments of the present invention, the current flow rate value can also be used to determine whether the impact force formed during the process of switching from fast to slow output has ended. When the current flow rate value is positive, it can be determined that the impact force release has ended. That is, when the weight continuously increases, it is a positive flow rate, which means that the impact force has ended.

[0067] Step A2, calculate the air quantity in real time, specifically as follows:

[0068] Airborne volume = Current flow rate × Airborne time

[0069] Among them, the time in the air is the time taken for the drop, which is calculated by gravity acceleration, and the current flow rate is calculated in step A1.

[0070] Once the quantitative equipment is assembled, the height from the discharge port to the hopper remains constant, thus the drop is fixed. Specifically, the drop is automatically compensated. That is, at the moment the slow-feed output ends, some material, having already left the feeding device, remains in mid-air and eventually falls into the weighing hopper. The weight of this portion of material is called the drop or air volume. The time it takes for this portion of material to travel from the air to the weighing hopper is the time taken for the drop, i.e., the air time. Simultaneously, the air time calculated based on gravitational acceleration is also essentially constant. Traditional instruments control the closing of the discharge port with a fixed air volume. When the material density and flowability change, the actual air volume will change accordingly. Therefore, this invention uses dynamically calculated air volume as the criterion for stopping the slow-feed output, effectively solving the impact of changes in density and flowability.

[0071] Step A3: Based on the comparison with the target quantity, determine whether the conditions for stopping the slow increment output have been met. Specifically, the conditions for stopping the slow increment output include the following formula:

[0072] Current weight ≥ target weight - air weight (1)

[0073] Current weight < Target weight - Aerial weight (2)

[0074] If Formula 1 is satisfied, the slow feed rate output stops. If Formula 2 is satisfied, the feed rate continues to increase until the target amount is reached. The current weight refers to the current weighing weight of the weighing hopper, the target amount refers to the set target weight, and the air weight refers to the weight of the material after leaving the feeding device, still in mid-air, and eventually falling into the weighing hopper.

[0075] Step S5: After the slow feed output stops, record the time taken for the entire slow feed output process and the current actual measured weight.

[0076] Specifically, the actual measured weight is the weight waiting for the weighing hopper weight to stabilize and enter the fixed value record. Furthermore, the stabilization of the weighing hopper weight is specifically defined as: the change in the weighing hopper weight within a certain period is less than the set range.

[0077] Step S6: After recording the current actual measured weight, enter correction mode.

[0078] Specifically, the correction mode includes the following steps:

[0079] Step B1 involves correcting the fast-acceleration time by using the difference between the planned slow-acceleration time and the actual slow-acceleration time; the specific formula for correcting the fast-acceleration time is as follows:

[0080] New fast-addition time = Old fast-addition time + (Slow-addition actual time - Slow-addition planned time) × Adjustment ratio;

[0081] Specifically, since fast acceleration time and slow acceleration time are inversely proportional—the more fast acceleration time, the less slow acceleration time—when there is a deviation between the slow acceleration time and the planned slow acceleration time, the slow acceleration time of the next package can be corrected by adjusting the fast acceleration time, ensuring that the slow acceleration time ultimately meets the planned slow acceleration time setting. Therefore, by measuring the time difference between the actual slow acceleration time and the planned slow acceleration time, and then using the ratio of the fast acceleration output speed to the slow acceleration output speed, the fast acceleration time correction range can be accurately calculated. By using a set correction ratio coefficient, the fast acceleration time can be reliably corrected, and the maximum speed can be reached after several corrections. The correction ratio is a percentage, with fast acceleration set to 100% and slow acceleration to 50%. For example, if the slow acceleration time is 0.6 seconds longer, the theoretical calculation requires a 0.3-second fast acceleration correction. However, due to the non-linearity between the actual slow acceleration speed and the actual flow rate, a correction of only 0.2 seconds may be sufficient to meet the requirements. In this case, only 66% of the theoretical value needs to be corrected, without complete correction, to prevent overcorrection. In this invention, the correction ratio is usually set to 30%-50%. If a single correction fails to achieve the target result, multiple corrections are required to achieve the highest speed.

[0082] Step B2 involves correcting the new in-flight time using the difference between the actual measured weight and the target weight; the formula for correcting the new in-flight time is as follows:

[0083] New air time = Old air time + (Actual measured weight - Target weight) × Correction ratio;

[0084] The new air time represents the time it takes for the material to fall from the air into the weighing hopper after the correction, which is the time used for the new air quantity. The old air time represents the time it took for the material to fall from the air into the weighing hopper before the correction, which is the time used for the old air quantity. The target quantity represents the set target weight. The actual measured weight represents the weight that is waiting for the weight in the weighing hopper to stabilize and enter the fixed value record.

[0085] Specifically, the accuracy of the actual measured weight depends only on the air volume, which in turn depends only on the setting of the air time and the calculation of the slow flow rate. When the calculation accuracy of the slow flow rate is reliable, the air volume is only absolutely related to the air time. Therefore, in this invention, by using the average error between the actual measured weight and the target weight and correcting the air time according to a certain correction ratio, the error between the actual measured weight and the target weight can be finally corrected.

[0086] Furthermore, in practical use, since the setting in step S5 consumes additional time to complete, and the air time is related to the drop, which in turn is related to the mechanical assembly and the target quantity setting, the air time will not change once the mechanical assembly is determined and the target quantity remains unchanged. Therefore, the correction process for the new air time also includes the following steps:

[0087] B20: Determine if the target quantity has changed. If the target quantity has changed, enter continuous correction mode; if the target quantity remains unchanged, enter discontinuous correction mode.

[0088] The continuous correction mode includes the following steps:

[0089] B200: Detects the weight of each package and executes a correction mode;

[0090] B201: In correction mode, check whether the package weight error is within the error range. If it exceeds the set error range value, return to step B200. If it does not exceed the set error range value, execute discontinuous correction mode.

[0091] Furthermore, the discontinuous correction mode includes the following steps:

[0092] B202: Obtain the quantity of weighed packages;

[0093] B203: Determine if the quantity of weighed packages is within the set quantity. If it is within the set quantity, execute a correction mode. 。

[0094] Step S7: After the correction mode is completed, return to step S2 to perform the next package measurement.

[0095] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0096] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. An adaptive quantitative measurement and control method, characterized in that, Includes the following steps: Set parameters; Start the instrument, begin measurement, and enter rapid output mode; Once the set fast acceleration time is reached, the fast acceleration output is turned off and the slow acceleration output is switched on, and the start time is recorded. After the slow increment prohibition comparison time is reached, it is determined when to stop the slow increment output; the slow increment prohibition comparison time means that a certain period of time is started from the moment the fast increment output ends to determine when to stop the slow increment output; After stopping the slow feed output, record the time taken for the entire slow feed output process and the current actual measured weight; Enter correction mode; After the correction mode is completed, return to the start metering stage to perform the metering of the next package; The correction mode includes the following steps: Correct the fast-acceleration time; Correcting time errors in flight; The correction mode includes the following steps: The fast-acceleration time correction is calculated using the following formula: New fast-addition time = Old fast-addition time + (Actual slow-addition time - Planned slow-addition time) × Adjustment ratio Wherein, the new fast-add time represents the output time of the fast-add phase after correction, the old fast-add time represents the output time of the fast-add phase before correction, the actual slow-add time represents the time spent in the actual slow-add phase, and the slow-add planned time represents the planned target time spent in the slow-add phase; the correction ratio is 30%-50%; The in-flight time correction is calculated using the following formula: New air time = Old air time + (Actual measured weight - Target quantity) × Correction ratio The new air time represents the time it takes for the material to fall from the air into the weighing hopper after the correction, which is the time used for the new air quantity. The old air time represents the time it takes for the material to fall from the air into the weighing hopper before the correction, which is the time used for the old air quantity. The target quantity represents the set target weight. The actual measured weight represents the weight waiting for the weight in the weighing hopper to stabilize and enter the fixed value record. The process of correcting the time in the air also includes the following steps: Determine if the target quantity has changed; if the target quantity has changed, enter continuous correction mode. If the target value remains unchanged, enter the discontinuous correction mode; The continuous correction mode includes the following steps: Detect the quantity of each package and execute the correction mode; In correction mode, check whether the new air time is within the set air time range. If it exceeds the set air time range, return to the previous step. If it does not exceed the set air time range, execute discontinuous correction mode. The discontinuous correction mode includes the following steps: Get the quantity of weighed packages; Based on the number of weighed packages obtained, determine whether the quantity is within the set quantity. If it does not exceed the set quantity, execute a correction mode.

2. The adaptive quantitative measurement and control method as described in claim 1, characterized in that: The parameters include: fast addition time, slow prohibition comparison time, and air time.

3. The adaptive quantitative measurement and control method as described in claim 1, characterized in that: The specific steps of the process for determining whether to stop the slow increase output include the following: Calculate current traffic in real time; Real-time calculation of air volume; Determine whether the condition for stopping the slow increase in output has been met.

4. The adaptive quantitative measurement and control method as described in claim 3, characterized in that: The current flow rate is calculated using the following formula: Current flow rate = Δ weight / Δ time Where current flow rate represents the flow rate of material during slow feed output, Δ weight represents the real-time weight within the flow calculation time period, and Δ time represents the flow calculation time period.

5. The adaptive quantitative measurement and control method as described in claim 1, characterized in that: Real-time air volume is calculated using the following formula: Airborne volume = Current flow × Airborne time The air quantity refers to the weight of the material when it leaves the feeding device and is still in mid-air before finally falling into the weighing hopper at the moment the slow feed output ends, and the air time refers to the time it takes for the material to leave the feeding device and fall into the weighing hopper at the moment the slow feed output ends.

6. The adaptive quantitative measurement and control method as described in claim 1, characterized in that: The conditions for stopping the slow increase output are as follows: If the current weight is greater than or equal to the target weight minus the air weight, stop the slow increase output; if the current weight is less than the target weight minus the air weight, continue to increase the output until the target weight is reached.

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