Method for improving weighing precision of intelligent vertical spiral bagging device

Abstract

According to the method for improving the weighing precision of the intelligent vertical spiral bagging device, the intelligent vertical spiral bagging device comprises a lifting stand column, a lifting motor is arranged at the upper end of the lifting stand column, the lifting motor is provided with a rotary encoder, and the lifting motor drives a weighing and bagging mechanism to ascend and descend along a guide rail on the lifting stand column; a weighing sensor signal of the weighing bagging mechanism is transmitted to the weighing instrument, the weighing instrument can transmit a weighing weight signal to the PLC control system, the weighing instrument can also receive weight data returned by the PLC control system, and the PLC control system is responsible for coordinating and controlling all actions of the whole vertical spiral bagging device. The method for improving the weighing precision of the intelligent vertical spiral bagging device comprises the following steps: measuring tare weight values in upper and lower intervals of an initial precise flow position in advance; the sperm flow position of each time of weighing and bagging needs to be dynamically determined, the tare weight value of the current sperm flow position is inquired and calculated, and the sperm flow threshold value is dynamically adjusted. According to the invention, weighing errors caused by material density changes and tare weight changes at different precise flow positions can be eliminated.

Description

Technical Field

[0001] The invention discloses a method for improving the weighing accuracy of an intelligent vertical spiral bagging device, and belongs to the field of powder packaging machinery. Background Art

[0002] Patent document CN111846305B discloses an intelligent vertical spiral bagging device, which can keep the distance between the spiral outlet and the material surface in the bag constant during the coarse flow feeding stage. After the coarse flow is completed, the bagging mechanism drops to a fixed fine flow position and continues to complete the fine flow feeding until the weighing is completed. Due to the change in the bulk density of the powder material, the total volume of the material in the bag, that is, the material surface height, is also changing at any time at the end of the coarse flow. When the bagging mechanism drops to a fixed fine flow position, the distance between the spiral outlet and the material surface in the bag is also constantly changing, causing the weight of the flying material in the air before the end of the fine flow to be unstable, thereby causing a large weighing error. The current weighing error is generally ±0.2%~±0.35%. Compared with the weighing error of ±0.1% of granular materials, it is necessary to further improve the weighing accuracy of the intelligent vertical spiral bagging device. Summary of the invention

[0003] In order to solve the problem that the weight of flying materials in the air is unstable during the fine flow stage of the existing intelligent vertical spiral bagging device, resulting in low weighing accuracy, the present invention proposes a method for improving the weighing accuracy of the intelligent vertical spiral bagging device, the intelligent vertical spiral bagging device comprises a lifting column 1, a lifting motor 2 is provided at the upper end of the lifting column 1, the lifting motor 2 is provided with a rotary encoder, the lifting motor 2 drives the weighing bagging mechanism 3 to move up and down along the guide rail on the lifting column 1, the weighing sensor signal of the weighing bagging mechanism 3 is transmitted to the weighing meter 4, the weighing meter 4 can transmit the weighing weight signal to the PLC control system 5, the weighing meter 4 can also receive the weight data sent back by the PLC control system 5, and the PLC control system 5 is responsible for coordinating and controlling each action of the entire intelligent vertical spiral bagging device; The method for improving the weighing accuracy of the intelligent vertical spiral bagging device comprises the following steps: S0: Set the initial position of the fine flow to the Y-axis origin Y(0), the high position of the fine flow a distance above the origin Y(0) to be Y(A), and the low position of the fine flow a distance below the origin Y(0) to be Y(-B); S1: The lifting motor 2 drives the weighing and bagging mechanism 3 to move to the initial position Y(0) of the fine flow, the weighing meter 4 sets the weight value of this position to 0, and the PLC control system 5 records the tare data G(0)=0 at the initial position; S2: The lifting motor 2 drives the weighing and bagging mechanism 3 to rise a distance dY, the weighing meter 4 measures the weight value at this position, and the PLC control system 5 records the tare data G(1dY)=Ga1 at this position; S3: Repeat step S2 until the weighing and bagging mechanism 3 rises to the fine flow high position Y (A), and the PLC control system 5 records a plurality of tare weight data corresponding to the position Y G(2dY)=Ga2, G(3dY)=Ga3, ..., G(ndY)=Gan; S4: the lifting motor 2 drives the weighing and bagging mechanism 3 to descend to the initial position Y (0) of the fine flow; S5: The lifting motor 2 drives the weighing and bagging mechanism 3 to descend a distance dY, the weighing meter 4 measures the weight value at this position, and the PLC control system 5 records the tare data G(-1dY)=Gb1 at this position; S6: Repeat step S5 until the weighing and bagging mechanism 3 descends to the fine flow low position Y (-B), and the PLC control system 5 records a plurality of tare weight data corresponding to the position Y G (-2dY) = Gb2, G (-3dY) = Gb3, ..., G (-mdY) = Gbm; S7: the lifting motor 2 drives the weighing and bagging mechanism 3 to rise to the rough flow high position to start normal rough flow bagging and weighing. When the rough flow is finished, the PLC control system 5 calculates the distance L that the weighing and bagging mechanism 3 has dropped from the rough flow high position. This distance L is inversely proportional to the bulk density p of the material. Then the lifting motor 2 drives the weighing and bagging mechanism 3 to drop a distance C=k1*L (where k1 is a constant) to continue fine flow feeding and weighing. At the same time, the PLC control system 5 calculates which two recorded position points between Y(A) and Y(-B) the position Y(y) of the weighing and bagging mechanism 3 is based on the position Y(y) of the weighing and bagging mechanism 3 at this time, and calculates the tare data Gy corresponding to the position Y(y) by interpolation method. The PLC control system 5 transmits this tare data Gy to the weighing instrument 4. S8: The weighing meter 4 recalculates the fine flow threshold value J(y)=J(0)+Gy according to the tare weight data Gy, wherein J(0) is the fine flow threshold value at the preset fine flow initial position Y(0); S9: The weighing meter 4 completes the fine flow feeding and ends the weighing according to the fine flow threshold J(y), and the lifting motor 2 drives the weighing and bagging mechanism 3 to descend to the lower position to release the full bag, completing a material bagging and weighing process; S10: Repeat steps S7 to S9 to complete the bagging and weighing process of a certain amount of materials; S11: according to the number of bagging weighing times and the accumulated working time completed by the intelligent vertical spiral bagging device, steps S1 to S6 are performed regularly, and then the bagging weighing process of steps S7 to S10 is performed.

[0004] The beneficial effects of the present invention are: A. After the coarse flow feeding is finished, the distance C that the weighing bagging mechanism 3 descends is C=k1*L, and the weight of the flying materials in the air at the end of the fine flow feeding is Jf=k2*C*p. Because the distance C is inversely proportional to the bulk density p of the material, Jf=k2*k3, that is, the weight of the flying materials in the air will be a constant and will not be affected by the change of the bulk density of the material, thereby improving the weighing accuracy; B. Using the pre-determined tare weight data of multiple positions within the upper and lower intervals of the initial fine flow position, the interpolation method is used to calculate the tare weight value Gy of the position where the weighing and bagging mechanism 3 is located at each fine flow, and Gy is calculated in the final fine flow threshold value J(y), thereby eliminating the weighing error caused by the inconsistent tare weight values ​​when the weighing and bagging mechanism 3 is at different height positions; C. By regularly measuring the tare weight data of multiple positions within the upper and lower intervals of the initial fine flow position, the influence of tare weight changes caused by the wear of the lifting guide rail can be eliminated, and the long-term stability of weighing accuracy can be maintained; D. The weight of flying materials in the air is not affected by changes in material density, the influence of tare weight at different heights is eliminated, and the influence of tare weight changes caused by wear of the lifting guide rails is avoided, so that the weighing accuracy of the intelligent vertical spiral bagging device can be greatly improved, and it can maintain long-term stable operation, and the weighing accuracy can be increased to ±0.1%~±0.2%. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Figure 1 It is a front view of the intelligent vertical spiral bagging device of the present invention.

[0006] Figure 2 It is a flow chart of measuring tare weight at different height positions in the present invention.

[0007] Figure 3 It is a flow chart of weighing and bagging in the present invention. DETAILED DESCRIPTION

[0008] The specific implementation of the present invention is shown in Figures 1 to 3 , a method for improving the weighing accuracy of an intelligent vertical spiral bagging device, the intelligent vertical spiral bagging device comprises a lifting column 1, a lifting motor 2 is provided at the upper end of the lifting column 1, the lifting motor 2 is provided with a rotary encoder, the lifting motor 2 drives a weighing bagging mechanism 3 to move up and down along a guide rail on the lifting column 1, the weighing sensor signal of the weighing bagging mechanism 3 is transmitted to a weighing meter 4, the weighing meter 4 can transmit the weighing weight signal to a PLC control system 5, the weighing meter 4 can also receive the weight data returned by the PLC control system 5, and the PLC control system 5 is responsible for coordinating and controlling each action of the entire intelligent vertical spiral bagging device; The method for improving the weighing accuracy of the intelligent vertical spiral bagging device comprises the following steps: S0: Set the initial position of the fine flow to the Y-axis origin Y(0), the fine flow high position 100 mm above the origin Y(0) to Y(100), and the fine flow low position 100 mm below the origin Y(0) to Y(-100); S1: The lifting motor 2 drives the weighing and bagging mechanism 3 to move to the initial position Y(0) of the fine flow, the weighing meter 4 sets the weight value of this position to 0, and the PLC control system 5 records the tare data G(0)=0 at the initial position; S2: The lifting motor 2 drives the weighing and bagging mechanism 3 to rise a distance dY=20 mm, the weighing meter 4 measures the weight value at this position, and the PLC control system 5 records the tare data G(20)=Ga1 at this position; S3: Repeat step S2 until the weighing and bagging mechanism 3 rises to the fine flow high position Y (100), and the PLC control system 5 records four tare weight data corresponding to position Y: G (40) = Ga2, G (60) = Ga3, G (80) = Ga4, G (100) = Ga5; S4: the lifting motor 2 drives the weighing and bagging mechanism 3 to descend to the initial position Y (0) of the fine flow; S5: The lifting motor 2 drives the weighing and bagging mechanism 3 to descend by a distance dY=20 mm, the weighing meter 4 measures the weight value at this position, and the PLC control system 5 records the tare data G(-20)=Gb1 at this position; S6: Repeat step S5 until the weighing and bagging mechanism 3 drops to the fine flow low position Y (-100), and the PLC control system 5 records four tare weight data corresponding to position Y: G (-40) = Gb2, G (-60) = Gb3, G (-80) = Gb, G (-100) = Gb5; S7: the lifting motor 2 drives the weighing and bagging mechanism 3 to rise to the rough flow high position to start normal rough flow bagging and weighing. When the rough flow is finished, the PLC control system 5 calculates the distance L that the weighing and bagging mechanism 3 has dropped from the rough flow high position. This distance L is inversely proportional to the bulk density p of the material. Then the lifting motor 2 drives the weighing and bagging mechanism 3 to drop a distance C=k1*L (where k1 is a constant) to continue fine flow feeding and weighing. At the same time, the PLC control system 5 calculates which two recorded position points between Y(100) and Y(-100) are between the position Y(y) of the weighing and bagging mechanism 3 at this time, and uses the interpolation method to calculate the tare data Gy corresponding to the position Y(y). The PLC control system 5 transmits this tare data Gy to the weighing instrument 4. S8: The weighing meter 4 recalculates the fine flow threshold value J(y)=J(0)+Gy according to the tare weight data Gy, wherein J(0) is the fine flow threshold value at the preset fine flow initial position Y(0); S9: The weighing meter 4 completes the fine flow feeding and ends the weighing according to the fine flow threshold J(y), and the lifting motor 2 drives the weighing and bagging mechanism 3 to descend to the lower position to release the full bag, completing a material bagging and weighing process; S10: Repeat steps S7 to S9 to complete the bagging and weighing process of a certain amount of materials; S11: according to the number of bagging weighing times and the accumulated working time completed by the intelligent vertical spiral bagging device, steps S1 to S6 are performed regularly, and then the bagging weighing process of steps S7 to S10 is performed.

Claims

1. A method for improving the weighing accuracy of an intelligent vertical spiral bagging device, the intelligent vertical spiral bagging device comprising a lifting column (1), a lifting motor (2) being provided at the upper end of the lifting column (1), the lifting motor (2) being provided with a rotary encoder, the lifting motor (2) driving a weighing bagging mechanism (3) to move up and down along a guide rail on the lifting column (1), the weighing sensor signal of the weighing bagging mechanism (3) being transmitted to a weighing meter (4), the weighing meter (4) being able to transmit the weighing weight signal to a PLC control system (5), the weighing meter (4) being able to receive weight data returned by the PLC control system (5), the PLC control system (5) being responsible for coordinating and controlling each action of the entire intelligent vertical spiral bagging device; The method for improving the weighing accuracy of the intelligent vertical spiral bagging device comprises the following steps: S0: Set the initial position of the fine flow to the Y-axis origin Y(0), the high position of the fine flow a distance above the origin Y(0) to be Y(A), and the low position of the fine flow a distance below the origin Y(0) to be Y(-B); S1: The lifting motor (2) drives the weighing and bagging mechanism (3) to move to the initial position Y (0) of the fine flow, the weighing instrument (4) sets the weight value of this position to 0, and the PLC control system (5) records the tare data G (0) = 0 at the initial position; S2: The lifting motor (2) drives the weighing and bagging mechanism (3) to rise a distance dY, the weighing meter (4) measures the weight value at this position, and the PLC control system (5) records the tare data G(1dY)=Ga1 at this position; S3: Repeat step S2 until the weighing and bagging mechanism (3) rises to the fine flow high position Y (A), and the PLC control system (5) records a plurality of tare weight data corresponding to the position Y G(2dY)=Ga2, G(3dY)=Ga3, ..., G(ndY)=Gan; S4: the lifting motor (2) drives the weighing and bagging mechanism (3) to descend to the initial position Y (0) of the fine flow; S5: the lifting motor (2) drives the weighing and bagging mechanism (3) to descend a distance dY, the weighing meter (4) measures the weight value at this position, and the PLC control system (5) records the tare data G(-1dY)=Gb1 at this position; S6: Repeat step S5 until the weighing and bagging mechanism (3) descends to the fine flow low position Y (-B), and the PLC control system (5) records a plurality of tare weight data corresponding to the position Y G (-2dY) = Gb2, G (-3dY) = Gb3, ..., G (-mdY) = Gbm; S7: The lifting motor (2) drives the weighing and bagging mechanism (3) to rise to the rough flow high position to start normal rough flow bagging and weighing. When the rough flow is finished, the PLC control system (5) calculates the distance L that the weighing and bagging mechanism (3) has descended from the rough flow high position. This distance L is inversely proportional to the bulk density p of the material. Then the lifting motor (2) drives the weighing and bagging mechanism (3) to descend a distance C=k1*L (where k1 is a constant) to continue fine flow feeding and weighing. At the same time, the PLC control system (5) calculates which two recorded positions between Y(A) and Y(-B) the position Y(y) is based on the position Y(y) of the weighing and bagging mechanism (3) at this time, and calculates the tare data Gy corresponding to the position Y(y) by using the interpolation method. The PLC control system (5) transmits the tare data Gy to the weighing instrument (4); S8: the weighing instrument (4) recalculates the fine flow threshold value J(y)=J(0)+Gy according to the tare weight data Gy, wherein J(0) is the fine flow threshold value at the preset fine flow initial position Y(0); S9: The weighing instrument (4) completes the fine flow feeding and ends the weighing according to the fine flow threshold value J(y), and the lifting motor (2) drives the weighing bagging mechanism (3) to descend to the lower position to release the full bag, completing a material bagging and weighing process; S10: Repeat steps S7 to S9 to complete the bagging and weighing process of a certain amount of materials; S11: according to the number of bagging weighing times and the accumulated working time completed by the intelligent vertical spiral bagging device, steps S1 to S6 are performed regularly, and then the bagging weighing process of steps S7 to S10 is performed.

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