An adaptive anti-dripping filling machine based on residual liquid state recognition and a control method thereof

Abstract

The present application relates to the technical field of filling machine, in particular to a self-adaptive anti-dripping filling machine based on residual liquid state recognition and a control method, the filling machine is provided with a main filling channel with outlet downward, a back suction channel adjacent to the outlet side of the main filling channel and a residual liquid buffer cavity in the filling head shell, and is configured with a stop valve assembly, a terminal sealing reset member, a negative pressure back suction assembly, a sensor group, a control box and a pump valve driving module. The controller in the control box determines the residual liquid risk level according to the pressure, flow, weight or motor current state signal at the end of filling stage, and links the servo metering pump deceleration, the stop valve early closing, the negative pressure back suction pulse and the terminal sealing reset, so that the residual liquid at the outlet side is buffered, back suctioned or blocked, thereby reducing the dripping and bottle mouth pollution of different materials and end states.

Description

Technical Field

[0001] This invention relates to the field of filling machine technology, and in particular to an adaptive anti-drip filling machine and control method based on residual liquid state recognition. Background Technology

[0002] Filling machines are used on food, daily chemical, pharmaceutical, and fine chemical production lines to quantitatively inject liquids, pastes, or materials with a certain degree of fluidity into containers. Common filling equipment typically relies on metering pumps, filling heads, shut-off valves, and conveying and positioning mechanisms to complete the feeding, positioning, injection, and shutdown operations. For materials with low viscosity, the liquid column on the outlet side is prone to continue to sag after filling due to gravity and inertia; for materials with high viscosity or a tendency to string, residual liquid easily forms at the end of the filling head. Both situations can cause bottle mouth contamination, conveyor belt contamination, or instability in subsequent capping and sealing processes.

[0003] Existing anti-drip structures mostly employ mechanical anti-drip valves, spring ball valves, fixed negative pressure back suction, or fixed delayed valve closing. These methods can handle some standard materials, but when the same equipment needs to be compatible with different materials, different filling speeds, and different bottle mouth conditions, the fixed valve closing time or fixed back suction volume is often difficult to adapt simultaneously. If the back suction is insufficient, residual liquid on the outlet side will still drip after the filling head leaves the bottle mouth; if the back suction is too strong, it may introduce air, causing metering errors or causing stringing and rebound of highly viscous materials. Solutions that rely solely on visual observation of dripping at the bottle mouth are usually judged after dripping has already occurred, making it difficult to coordinate the pump, valve, back suction, and sealing actions before the filling process ends.

[0004] Therefore, there is a need for filling equipment capable of identifying residual liquid risk at the end of the filling process based on signals such as pressure, flow rate, weight, motor load, or bottle mouth status, and translating the identification results into actionable actions such as pump deceleration, early valve closure, back suction, and end seal reset. This equipment should not rely on a single valve or a fixed back suction volume for anti-drip capability; instead, the filling head structure, sensor sampling, drive module, and control method should all contribute to the anti-drip function. Summary of the Invention

[0005] The purpose of this invention is to provide an adaptive anti-drip filling machine and control method based on residual liquid state recognition, which solves the problem that the fixed anti-drip action is difficult to be compatible with the residual liquid state on the outlet side at the end of the filling stage as the material and working conditions change.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: an adaptive anti-drip filling machine based on residual liquid state recognition, comprising a frame, a conveying and positioning platform mounted on the frame, a feeding tank, a servo metering pump, and a filling head housing. A main filling channel is formed within the filling head housing, arranged vertically along the filling head housing with its outlet facing the bottle neck of the container to be filled. The filling machine also includes a back suction channel, a residual liquid buffer chamber, a shut-off valve assembly, an end-sealing reset component, a negative pressure back suction assembly, a sensor group, a control box, and a pump and valve drive module. The back suction channel is adjacent to the outlet side of the main filling channel; the residual liquid buffer chamber is located in the end region between the main filling channel and the back suction channel; the shut-off valve assembly is located on the upstream side of the main filling channel; the end-sealing reset component is located at the liquid outlet end of the filling head housing; and the negative pressure back suction assembly is connected to the back suction channel. The sensor group inputs the status signal of the filling end stage to the controller in the control box. The controller generates the residual liquid risk level according to the status signal and controls the deceleration action of the servo metering pump, the early closing action of the shut-off valve assembly, the back suction pulse action of the negative pressure back suction assembly, and the reset sealing action of the end seal reset component through the pump valve drive module.

[0007] Preferably, the sensor group includes a pressure sensor and a flow sensor. The pressure sensor is located near the filling head housing or the connected flow channel to collect pressure change signals on the outlet side; the flow sensor is located on the outlet side of the servo metering pump to collect tail flow change signals at the end of the filling process. The pressure change signal reflects the depressurization process of the liquid column on the outlet side, and the tail flow change signal reflects the residual flow after the metering pump stops supplying liquid. The combination of the two can provide different sources of information for identifying residual liquid risks.

[0008] Preferably, the sensor group also includes at least one of a weighing sensor and a motor current sampling unit. The controller uses at least two of the following signals as inputs for residual liquid status identification: outlet pressure change signal, wake change signal, weight increment change signal, and motor current change signal. The weight increment change signal reflects the final state of the actual material received in the container, and the motor current change signal reflects the load change of the servo metering pump in the final stage, enabling the controller to determine the residual liquid status from multiple perspectives, including the flow channel, the container, and the drive load.

[0009] Preferably, the residual liquid buffer chamber is arranged around or adjacent to the outlet side of the main filling channel, and the inlet of the back suction channel is connected to the residual liquid buffer chamber. This allows the liquid remaining on the outlet side after the main filling channel stops supplying liquid to first enter the residual liquid buffer chamber, and then be drawn back by the negative pressure back suction component. This arrangement ensures that the residual liquid on the outlet side is not directly suspended on the nozzle edge, but is confined to a recoverable cavity position, thus providing a stable target for subsequent back suction pulses and end seal reset.

[0010] Preferably, the end-sealing reset component includes an elastic sealing ring or a resettable sealing component surrounding the outlet of the main filling channel. After the shut-off valve assembly is closed, the end-sealing reset component, driven by the pump valve drive module or by its own reset action, adheres to the outlet edge of the main filling channel, so that any trace residual liquid that has not been drawn back on the outlet side is constrained by the sealing component, reducing the dripping path after the filling head leaves the bottle mouth.

[0011] Preferably, the control box contains a controller, a sampling, conditioning, and amplification unit, and a pump and valve drive unit. The sampling, conditioning, and amplification unit receives the sampling signals output by the sensor group and sends them to the controller. The pump and valve drive unit receives the control commands output by the controller and outputs drive signals to the servo metering pump, the shut-off valve assembly, the negative pressure back suction assembly, and the end seal reset component. The sampling, conditioning, and execution drive are separated, which functionally separates weak signal sampling from the execution component drive, reducing the impact of drive-side disturbances on the residual liquid status identification input.

[0012] Preferably, the controller may include a residual liquid risk identification unit, a termination action generation unit, and an execution feedback correction unit. The residual liquid risk identification unit receives pressure, flow rate, weight, motor current, or visual status signals and forms a residual liquid risk level; the termination action generation unit converts the residual liquid risk level into pump deceleration, early valve closure, back suction pulse, and seal reset commands; the execution feedback correction unit records the feedback risk and updates the timing parameters for the next filling termination stage.

[0013] This invention also provides a control method, comprising: acquiring status signals output by a sensor group at the end of the filling stage; extracting residual liquid status characteristics from the status signals; determining the residual liquid risk level by a controller based on the residual liquid status characteristics; generating deceleration commands for the servo metering pump, early valve closing commands for the shut-off valve assembly, back-suction pulse commands for the negative pressure back-suction assembly, and sealing reset commands for the end-seal reset component based on the residual liquid risk level; and outputting the above commands to the corresponding actuators through a pump and valve drive module. This method directly maps the residual liquid status identification results to the relative execution timing parameters of multiple actuators, so that the end-of-fill stage no longer relies solely on a fixed back-suction volume or a single valve action, but can adjust the anti-drip action according to the actual residual liquid risk.

[0014] Compared with the prior art, the advantages and positive effects of the present invention are as follows: The main filling channel with its outlet facing downwards, the back suction channel adjacent to the outlet side, and the residual liquid buffer chamber together define the path for receiving and recovering residual liquid on the outlet side, ensuring that the residual liquid after the supply stops is in an identifiable, back suctionable, and sealable position. The controller generates a residual liquid risk level based on status signals such as pressure, flow rate, weight, or motor current, providing a basis for the anti-drip action from the actual end-of-fill state. The pump and valve drive module converts the residual liquid risk level into a combination of actions including servo metering pump deceleration, early closure of the shut-off valve, negative pressure back suction pulse, and end seal reset, thereby reducing the risk of outlet dripping, bottle mouth contamination, and over-suction under different materials and different end-of-fill states. Attached Figure Description

[0015] Figure 1 This is an isometric schematic diagram of the filling machine of the present invention.

[0016] Figure 2 This is a front view of the filling machine of the present invention.

[0017] Figure 3 This is a cross-sectional schematic diagram of the filling head and its anti-drip actuator of the present invention. Figure 2 (Point A in the middle).

[0018] Figure 4 This is a schematic diagram of the circuit principle of the filling machine of the present invention.

[0019] Figure 5 This is a functional block diagram of the filling machine of the present invention.

[0020] Figure 6 This is a flowchart illustrating the control method of the present invention.

[0021] Figure 7 This is a timing diagram of the filling completion stage of the present invention.

[0022] Explanation of reference numerals in the attached drawings: 1. Frame; 2. Conveying and positioning platform; 3. Feeding tank; 4. Servo metering pump; 5. Filling head housing; 6. Main filling channel; 7. Back suction channel; 8. Residual liquid buffer chamber; 9. Shut-off valve assembly; 10. End seal reset component; 11. Negative pressure back suction assembly; 12. Pressure sensor; 13. Flow sensor; 14. Control box; 15. Pump and valve drive module; 16. Vision inspection unit; 17. Container positioning fixture; 18. Container to be filled; 401. Power supply and protection terminal; 402. Surge protection device; 403. Controller; 404. Pressure sensor; 405. Flow sensor; 406. Weighing sensor; 407. Motor current sampling unit; 408. Sampling current limiting resistor; 409. Filter capacitor; 410. Sampling conditioning and amplification unit. ; 411. Pump and valve drive unit; 412. Pump drive switch; 413. Servo metering pump actuator; 414. Shut-off valve actuator; 415. Negative pressure back suction actuator; 416. End sealing actuator; 417. Visual inspection signal input interface; 501. Residual liquid risk identification unit; 502. End action generation unit; 503. Execution feedback correction unit; 601. Acquire filling end stage signal; 602. Extract residual liquid state characteristics; 603. Determine residual liquid risk level; 604. Correct deceleration and valve closing timing; 605. Output back suction pulse and seal reset; 606. Record feedback and update timing parameters; 701. Sampling signal; 702. Pump deceleration command; 703. Early valve closing command; 704. Back suction pulse command; 705. Seal reset command. Detailed Implementation

[0023] The present invention will be further described below with reference to the accompanying drawings. It should be understood that the following embodiments are used to illustrate the structural organization, control relationships, and working process of the present invention, and do not limit the specific dimensions, materials, driving energy forms, or sensor models of each component. For different materials, bottle types, and production cycles, relevant components can be adapted while maintaining the core relationships of the present invention.

[0024] like Figures 1 to 3 As shown, the filling machine of the present invention is based on the frame 1, and the conveying and positioning platform 2 is set on the frame 1 to deliver the container 18 to be filled to the filling station. Figure 1The spatial relationship between the frame 1, conveyor positioning platform 2, feeding tank 3, servo metering pump 4, filling head housing 5, shut-off valve assembly 9, negative pressure back suction assembly 11, pressure sensor 12, flow sensor 13, control box 14, pump and valve drive module 15, vision inspection unit 16, container positioning fixture 17, and the container to be filled 18 is shown in isometric view. In this figure, the filling head housing 5 is positioned above the container to be filled 18. The servo metering pump 4 and flow sensor 13 are located on the liquid supply side of the filling head housing 5. The negative pressure back suction assembly 11 is located on the side where the back suction channel 7 is located. The pressure sensor 12 is located near the flow channel of the filling head housing 5. The vision inspection unit 16 faces the liquid outlet and bottle neck area. Figure 1 Instead of displaying the internal cavities transparently, the downward direction of the main filling channel 6 outlet is marked at the visible liquid outlet end. The cross-sectional relationship between the internal channels and the buffer chamber is... Figure 3 As shown.

[0025] A container positioning fixture 17 is mounted on the conveyor positioning platform 2. The fixture 17 limits the position of the bottle neck of the container 18 to be filled by clamping, limiting, or supporting, preventing the container 18 from swaying with the conveyor belt during the final stage of filling. The feeding tank 3 and the servo metering pump 4 form the feeding and quantitative output path. A flow sensor 13 is connected to the outlet side of the servo metering pump 4, and the flow sensor 13 is then connected to the main filling channel 6 inside the filling head housing 5. The filling head housing 5 is located above the bottle neck of the container 18. The main filling channel 6 is arranged vertically along the filling head housing 5, with the outlet facing downwards and aligned with the bottle neck area of ​​the container 18. A pressure sensor 12 is installed in the filling head housing 5 or in a flow channel adjacent to it to obtain pressure changes on the outlet side. A control box 14 is located on one side of the conveyor positioning platform 2. A pump valve drive module 15 is installed inside or connected to the control box 14, enabling the control box 14 to receive sensor signals and output drive commands.

[0026] Structurally, the filling head housing 5 is not a separate outlet pipe, but a processing node that simultaneously supports the main filling channel 6, the back suction channel 7, the residual liquid buffer chamber 8, the shut-off valve assembly 9, the end seal reset component 10, the negative pressure back suction assembly 11, and the pressure sensor 12. The main filling channel 6 undertakes the normal filling flow path, with its outlet facing downwards to form a gravity-directed channel from the upstream liquid supply to the bottle mouth area; the back suction channel 7 is adjacent to the outlet side of the main filling channel 6, and the residual liquid buffer chamber 8 is arranged at the end area of ​​both. The shut-off valve assembly 9 is located on the upstream side of the main filling channel 6 and is used to cut off the continuous liquid supply before and after the filling is completed; the end seal reset component 10 is located at the outlet edge of the main filling channel 6 and is used to form a reset contact with the nozzle edge after the liquid supply stops; the negative pressure back suction assembly 11 acts on the residual liquid buffer chamber 8 through the back suction channel 7, so that the residual liquid near the outlet has a path to be recovered before leaving the bottle mouth.

[0027] Figure 2 The section cut is shown at position AA. This section cut is along the vertical centerline of the filling head housing 5 and covers the end area containing the main filling channel 6, the back suction channel 7, the residual liquid buffer chamber 8, the end sealing reset component 10, and the negative pressure back suction assembly 11. Through this section cut, the internal flow path of the filling head housing 5, which is not visible in a standard outline drawing, can be presented. Figure 3 The structure in.

[0028] like Figure 3 The diagram shows the solid wall thickness of the filling head housing 5, the main filling channel 6 with its outlet facing downwards, the back suction channel 7 adjacent to the outlet side of the main filling channel 6, and the residual liquid buffer chamber 8 located in the end region. The lower end of the main filling channel 6 faces the bottle mouth of the container 18 to be filled. The residual liquid buffer chamber 8 surrounds or is adjacent to the outlet side of the main filling channel 6. The inlet of the back suction channel 7 is located near the residual liquid buffer chamber 8 and is connected to the negative pressure back suction assembly 11. The shut-off valve assembly 9 is located upstream of the main filling channel 6, and the end sealing reset member 10 is arranged around the outlet edge of the main filling channel 6. When the shut-off valve assembly 9 is closed, the end sealing reset member 10 retracts itself or is driven to retract and adhere to the outlet edge of the main filling channel 6, preventing any trace residual liquid that has not been back suctioned from falling freely along the outer edge of the nozzle.

[0029] During implementation, the controller inside the control box 14 receives status signals output by a sensor group, which may include a pressure sensor 12, a flow sensor 13, a weighing sensor, a motor current sampling unit, and a vision detection unit 16. Near the end of the filling process, the controller does not only read a single switch signal, but also comprehensively considers pressure signals, flow signals, weight signals, current signals, or bottle mouth image status to determine whether there is a risk of continued dripping, stringing, or over-absorption of residual liquid on the outlet side. The controller then controls the servo metering pump 4, the shut-off valve assembly 9, the negative pressure back-suction assembly 11, and the end seal reset component 10 via the pump and valve drive module 15. First, the servo metering pump 4 enters a deceleration and finalization state; then, the shut-off valve assembly 9 is closed prematurely to reduce continued liquid supply; next, the negative pressure back-suction assembly 11 applies a back-suction pulse to the residual liquid buffer chamber 8; and finally, the end seal reset component 10 resets the seal at the outlet edge.

[0030] The complete working chain of this invention begins with the stable positioning of the container to be filled 18 and ends with the controlled recovery and sealing of residual liquid on the outlet side. After the container to be filled 18 enters the conveying and positioning platform 2, the container positioning fixture 17 first defines the center of the bottle mouth, so that the main filling channel 6 in the filling head housing 5 can be aligned with the bottle mouth area; the feeding tank 3 feeds material to the main filling channel 6 via the servo metering pump 4, and the shut-off valve assembly 9 maintains the liquid supply path during the normal filling stage, while the back suction channel 7 and the residual liquid buffer chamber 8 are in a state of waiting to receive residual liquid. When the filling volume is close to the end position, the pressure sensor 12, flow sensor 13, weighing sensor and motor current sampling unit send the outlet side pressure, wake, weight increment and pump load change to the control box 14. If the residual liquid risk is determined to be low, the controller can allow the servo metering pump 4 to decelerate smoothly and allow the end seal reset component 10 to complete a normal reset; if the residual liquid risk is determined to be high, the controller first allows the servo metering pump 4 to reduce its output, then allows the shut-off valve assembly 9 to cut off the continuous liquid replenishment of the main filling channel 6 in advance, then drives the negative pressure back suction assembly 11, so that the liquid in the residual liquid buffer chamber 8 is carried away from the outlet edge through the back suction channel 7, and finally drives the end seal reset component 10 to fit or approach the outlet of the main filling channel 6.

[0031] The key to this process lies in the fact that the main filling channel 6, the back suction channel 7, and the residual liquid buffer chamber 8 provide a structural path for the controlled migration of residual liquid. Pressure, flow rate, weight, and current signals provide input criteria for judging the state of residual liquid. The controller and pump-valve drive module 15 provide processing and output paths to convert the judgment results into pump deceleration, valve closure, back suction, and seal reset. Therefore, the anti-drip effect is not solely achieved by a single spring valve or a fixed back suction volume, but is jointly formed by the mechanical end effector, sensor sampling, control judgment, and the timing of the actuators. After filling, the controller can also use the pressure drop, tail flow convergence, weight stabilization, and motor load changes as the basis for correcting the parameters for the next action, so that the same equipment can still maintain the corresponding final stage action when the material viscosity, bottle mouth condition, or production cycle changes.

[0032] For low-viscosity materials, pressure and flow rates typically change rapidly, allowing the controller to shorten the back-suction pulse and prioritize seal reset. For high-viscosity or stringy materials, motor current and wake state better reflect pump end resistance, enabling the controller to schedule deceleration, valve closing, and back-suction actions closer to the moment before the bottle neck disengages. The negative pressure back-suction assembly 11 applies a short-term effect only to the vicinity of the residual liquid buffer chamber 8 and back-suction channel 7, preventing continuous suction along the entire feeding path. The end seal reset component 10 constrains the outlet edge after back-suction, preventing residual trace amounts of liquid from freely falling along the nozzle's outer edge. In this way, structural space, signal acquisition, judgment processing, and execution output are coordinated within the same filling end stage, forming a repeatable adaptive anti-drip closed loop.

[0033] The pressure sensor 12 is used to obtain the pressure release status at the end of the filling head housing 5 or near the flow channel. If the pressure continues to decrease slowly after the servo metering pump 4 decelerates, the controller can determine that there is still a significant liquid column momentum or material viscous resistance in the main filling channel 6. The flow sensor 13 is used to obtain the tail flow change at the outlet side of the servo metering pump 4. If the flow signal still has a tail after the liquid supply stops, the controller can determine that the back suction pulse and end seal reset action need to be advanced or enhanced. The weighing sensor is used to determine whether the weight increment of the container to be filled 18 tends to stabilize at the end stage, and the motor current sampling unit is used to determine whether the load of the servo metering pump 4 has dropped. The above signals do not need to be used simultaneously, but when at least two types of signals are combined, the controller can distinguish different residual liquid risks caused by material adhesion, pump end inertia, bottle mouth offset, or changes in drive load.

[0034] The vision detection unit 16 faces the liquid outlet of the filling head housing 5 or the bottle mouth area of ​​the container 18 to be filled. The vision detection unit 16 outputs the bottle mouth image status, which can characterize whether there are droplets, strands, or abnormal reflections in the bottle mouth area. In this invention, the vision detection unit 16 serves as an auxiliary input and is not used as the sole basis for anti-drip actions. This is because vision detection can usually only see the visible state already formed at the bottle mouth, while signals such as pressure, flow rate, weight, and motor current can reflect the finishing process in the channel before dripping. The controller can increase the residual liquid risk level when the vision detection unit 16 detects an anomaly, and can also continue to perform back suction and seal reset actions when the visual state is normal but the pressure or tail flow is abnormal.

[0035] like Figure 4As shown, the power supply and protection terminal 401 provides operating power to the controller 403 and the pump valve drive unit 411. The surge protection device 402 is connected to the power supply side of the power supply and protection terminal 401 to provide a discharge path when transient impacts are caused by external power supply or actuator switching. The pressure sensor 404 corresponds to the pressure sensor 12 at the filling head housing 5 or adjacent to the flow channel. The flow sensor 405 corresponds to the flow sensor 13 at the outlet side of the servo metering pump 4. The weighing sensor 406 and the motor current sampling unit 407 provide weight increment change signals and pump load change signals, respectively. The visual detection signal input interface 417 is connected to the visual detection unit 16 to provide bottle mouth image status signals. The above sampling signals can first pass through the sampling current limiting resistor 408 and the filter capacitor 409, and then enter the sampling conditioning and amplification unit 410, which sends them to the controller 403. The pump-valve drive unit 411 receives the end-stage command output by the controller 403, and the pump drive switch 412 applies the pump drive command to the servo metering pump actuator 413. The shut-off valve actuator 414, the negative pressure back suction actuator 415, and the end-sealing actuator 416 respectively drive the shut-off valve assembly 9, the negative pressure back suction assembly 11, and the end-sealing reset assembly 10. This circuit principle does not limit specific device models, but rather limits the functional connections between sampling input, control processing, and execution output.

[0036] like Figure 5 As shown, the residual liquid risk identification unit 501 receives pressure signals, flow signals, weight signals, and current signals, and can also receive bottle opening image status as auxiliary input. The residual liquid risk identification unit 501 forms a residual liquid risk level based on the effective feature set. The termination action generation unit 502 outputs a termination command based on the residual liquid risk level. The termination command is converted by the pump and valve drive unit 411 into deceleration drive, valve closing drive, back suction drive, and sealing drive, which are respectively applied to the servo metering pump actuator 413, the shut-off valve actuator 414, the negative pressure back suction actuator 415, and the end sealing actuator 416. The execution feedback correction unit 503 records the pressure, flow, weight, or current feedback status after back suction and seal reset, generates a feedback risk Rf, and sends the feedback result back to the residual liquid risk identification unit 501 or the termination action generation unit 502 for updating the pump deceleration advance, valve closing advance, back suction pulse parameters, or seal reset timing in the next filling end stage.

[0037] like Figure 6As shown, the control flow includes acquiring the filling end stage signal 601, extracting residual liquid state characteristics 602, determining the residual liquid risk level 603, correcting the deceleration and valve closing timing 604, outputting the backflow pulse and seal reset 605, and recording feedback and updating timing parameters 606. In step 603, when some sensors do not participate in this identification, the controller 403 only uses the effective feature set E and renormalizes the weights according to the sum of the basic weights corresponding to the effective features; the risk level is determined by mutually exclusive execution priorities of first judging high risk, then medium risk, and otherwise judging low risk. Steps 604 and 605 map low, medium, and high risks to combinations of pump deceleration, early valve closing, backflow pulse, and seal reset of different intensities, respectively. Step 606 obtains the feedback risk Rf within the feedback window Wf and updates at least one of the following in the next cycle: pump deceleration advance, valve closing advance, backflow pulse parameter, and seal reset timing within the safety boundary.

[0038] like Figure 7 As shown, sampling signal 701 is located within the end window W. Controller 403 determines the residual liquid risk level based on sampling signal 701 at the judgment point. Pump deceleration command 702 is output before or near the shut-off valve, causing servo metering pump actuator 413 to enter deceleration final stage; early valve closing command 703 subsequently acts on shut-off valve actuator 414 to cut off continuous liquid replenishment in main filling channel 6; back suction pulse command 704 acts on negative pressure back suction actuator 415 after shut-off valve operation, causing residual liquid to enter the negative pressure back suction path through residual liquid buffer chamber 8 and back suction channel 7; seal reset command 705 acts on end seal actuator 416 after back suction pulse, causing end seal reset actuator 10 to adhere to or approach the outlet edge of main filling channel 6. Low risk corresponds to a shorter or weaker backflow pulse; medium risk corresponds to deceleration and valve closure one control interval earlier, as well as a secondary backflow pulse; high risk corresponds to even earlier deceleration, early valve closure, and a tertiary backflow pulse not exceeding the maximum allowable limit of the formula. This timing sequence is consistent with the state sequence of normal liquid supply S01, early valve closure S02, negative pressure backflow S03, and seal reset S04. Feedback updates target the advance amount, pulse parameters, or reset time points corresponding to T1 to T4, maintaining the physical action chain of pump deceleration, valve closure, backflow, and seal reset.

[0039] In one embodiment, the controller samples pressure p, flow rate q, weight w, and servo metering pump motor current i within a final window W before the target filling volume is reached. The final window W can take N consecutive sampling points according to the controller's scanning cycle, where N is an integer range that can cover pump deceleration and valve closing response, and is not required to correspond to a specific equipment model. For the data within the window W, the controller calculates the pressure attenuation feature Fp, wake feature Fq, late weight increment feature Fw, and pump load feature Fi. Fp can be 1 minus the normalized ratio of the pressure drop from the start to the end of the window to the reference pressure difference; Fq can be the normalized ratio of the average positive wake within the window to the nominal flow rate of the formula; Fw can be the normalized ratio of the weight increment within the window to the target filling volume; and Fi can be the normalized ratio of the portion of the motor current higher than the no-load current within the window to the operating current range. All of the above features are limited to 0 to 1. When a sensor does not participate in this identification, only the effective feature set E is used for calculation, and the weights are renormalized according to the sum of the basic weights corresponding to the effective features.

[0040] In this embodiment, the basic weights can be set to 0.35 for Fp, 0.30 for Fq, 0.20 for Fw, and 0.15 for Fi. If all four features are valid, the controller will proceed according to... Calculate the residual liquid risk value; if some features are missing, then proceed as follows: The calculation is performed, where Fj belongs to the set of valid features E, and wj is the basic weight of that valid feature. The controller executes the process in the order of first judging high risk, then medium risk, and otherwise low risk: when R is not less than 0.60, or when both Fp and Fq are valid and simultaneously greater than 0.50, it is judged as high risk; if the high risk condition is not met, but R is not less than 0.30, or any valid feature is greater than 0.60, it is judged as medium risk; otherwise, it is judged as low risk. The above values ​​are dimensionless parameter boundaries for ease of implementation and debugging. The actual equipment can be modified according to the material formula without changing the input features, judgment priority, risk classification, and entity action mapping relationship.

[0041] The controller generates an end command based on the residual liquid risk level. The end command includes at least a pump deceleration command, an early valve closure command, a backflow pulse command, and a seal reset command. At low risk, the servo metering pump 4 decelerates according to the formula's deceleration slope, the shut-off valve assembly 9 closes at the target end time, the negative pressure backflow assembly 11 outputs a first-level short pulse, and then the end seal reset component 10 resets. At medium risk, the servo metering pump 4 decelerates one control interval earlier, the shut-off valve assembly 9 closes one control interval earlier, the negative pressure backflow assembly 11 outputs a second-level pulse, and performs a seal reset after the pressure trend enters the stable zone. At high risk, the servo metering pump 4 decelerates two control intervals earlier, the shut-off valve assembly 9 closes early after deceleration, the negative pressure backflow assembly 11 outputs a third-level pulse but does not exceed the formula's allowable upper limit, and then the end seal reset component 10 resets to fit the outlet edge. Thus, low, medium, and high risks correspond to combinations of pump deceleration, early valve closure, backflow pulse, and seal reset from weak to strong, rather than simply changing the state of a single valve component.

[0042] The execution feedback is used to record the retest status after the current filling is completed. After the backflow pulse and seal reset are completed, the controller recalculates the effective characteristics of pressure, flow rate, weight, or current within the feedback window Wf and obtains the feedback risk Rf. If Rf is greater than 0.45, or if the weight signal continues to increase after the filling head leaves the bottle, the risk level of the next filling stage is increased by one level or the backflow pulse parameter is increased by one discrete unit; if Rf is less than 0.20 and occurs M times consecutively, the controller reduces the backflow pulse parameter by one discrete unit or moves the valve closing advance by one control interval. All updates are subject to safety boundaries: the backflow pulse parameter does not exceed the upper limit allowed by the formula, and the valve closing advance must not be earlier than the minimum liquid supply time to ensure the target filling volume; when there are fewer than two types of effective status signals or the sensor fails, the controller returns to the preset safe closing action. The purpose of the execution feedback is not to allow the equipment to operate independently of the structure, but to link the retest status with the pump deceleration advance, valve closing advance, backflow pulse parameter, and seal reset time of the next cycle.

[0043] The structure and control method of this invention are applicable to liquids or semi-fluid materials of different viscosity grades. For low-viscosity materials, the main risk is that the liquid continues to drip along the outlet edge after the valve is closed. At this time, the fading trend of the pressure and flow signals is more sensitive, and the controller can focus on early valve closure and end seal reset. For high-viscosity materials, the main risk is material adhesion to the wall and stringing. At this time, changes in motor current, wake changes, and visual auxiliary status are more meaningful. The controller can focus on the coordination of pump deceleration, short-term back suction, and end sealing action. For materials that are prone to foaming or unsuitable for strong back suction, the controller can reduce the priority of the back suction pulse and rely more on the deceleration of the servo metering pump 4 and the sealing constraint of the end seal reset component 10.

[0044] The filling head housing 5 can be designed as a housing structure that is easy to disassemble and assemble, allowing the main filling channel 6, the back suction channel 7, and the residual liquid buffer chamber 8 to be rinsed or disassembled for maintenance during cleaning. The shut-off valve assembly 9, the end seal reset component 10, and the negative pressure back suction assembly 11 can be configured as replaceable modules to allow for replacement of seals or cleaning of the back suction channel 7 for different materials. The container positioning clamp 17 can be an adjustable clamp or a replaceable tray to accommodate different containers 18 to be filled. The above maintenance and adjustment structures do not change the core relationship of the invention; their function is to maintain the correspondence between the filling head end, sensor input, and actuator action.

[0045] In another implementation, the controller can associate residual liquid risk levels with the equipment formulation. Different material formulations can correspond to different default deceleration actions, early valve closing actions, backflow pulse actions, and seal reset actions. After the equipment starts producing a certain material, the controller gradually adjusts the timing parameters of the end stage based on pressure, flow rate, weight, or current feedback during continuous filling, making the anti-drip actions under the same formulation more adaptable to the actual flow state of the material. The formulation here does not require specific parameter values; it only needs to be able to store or recall material-related end-stage action strategies.

[0046] The control method of this invention may also include anomaly handling. When the controller does not receive sufficient status signals, a preset safety termination action can be adopted, namely, first reducing the output of the servo metering pump 4, then closing the shut-off valve assembly 9, and executing a short back-suction pulse and end seal reset. If the vision detection unit 16 detects an abnormality at the bottle opening but the pressure and flow signals are not abnormal, the controller can record this state as a feedback state instead of immediately adjusting all subsequent filling operations to high-risk actions. This approach can reduce the impact of a single sensor malfunction on the overall cycle time while retaining the auxiliary role of the bottle opening status in identifying residual liquid risks.

[0047] The above embodiments are only used to illustrate the structure and control relationship of the present invention. For those skilled in the art, without departing from the core concept of the present invention, equivalent substitutions can be made for the shape of the filling head housing 5, the arrangement of the back suction channel 7, the specific form of the residual liquid buffer chamber 8, the execution mode of the shut-off valve assembly 9, the reset mode of the end seal reset component 10, the combination mode of the sensor group, and the signal processing mode of the controller. These substitutions, as long as they still enable the residual liquid state recognition result to drive the servo metering pump to decelerate, close the valve in advance, perform negative pressure back suction, and trigger the linked anti-drip action of the end seal reset, all fall within the scope of implementation of the technical solution of the present invention.

Claims

1. An adaptive anti-drip filling machine based on residual liquid state recognition, comprising a frame (1), a conveying and positioning platform (2) disposed on the frame (1), a feeding tank (3), a servo metering pump (4), and a filling head housing (5), wherein a main filling channel (6) with an outlet facing the bottle mouth of the container (18) to be filled is formed inside the filling head housing (5); characterized in that: It also includes a back suction channel (7), a residual liquid buffer chamber (8), a shut-off valve assembly (9), an end seal reset component (10), a negative pressure back suction assembly (11), a sensor group, a control box (14), and a pump and valve drive module (15). The back suction channel (7) is arranged adjacent to the outlet side of the main filling channel (6). The residual liquid buffer chamber (8) is located in the end area between the main filling channel (6) and the back suction channel (7). The shut-off valve assembly (9) is located on the upstream side of the main filling channel (6). The end seal reset component (10) is located on the outlet side of the main filling channel (6). At the liquid outlet end of the head housing (5), the negative pressure back suction assembly (11) is connected to the back suction channel (7); the sensor group inputs the status signal of the filling end stage to the controller in the control box (14), the controller is configured to generate the residual liquid risk level according to the status signal, and control the deceleration action of the servo metering pump (4), the early closing action of the shut-off valve assembly (9), the back suction pulse action of the negative pressure back suction assembly (11), and the reset sealing action of the end seal reset component (10) through the pump valve drive module (15).

2. The adaptive anti-drip filling machine according to claim 1, characterized in that: The sensor group includes a pressure sensor (12) and a flow sensor (13). The pressure sensor (12) is located near the filling head housing (5) or the flow channel connected to it, and is used to collect the pressure change signal on the outlet side. The flow sensor (13) is located on the outlet side of the servo metering pump (4) and is used to collect the tail flow change signal at the end of the filling stage.

3. The adaptive anti-drip filling machine according to claim 2, characterized in that: The sensor group also includes at least one of a weighing sensor (406) and a motor current sampling unit (407). The controller uses at least two of the following signals as residual liquid status identification inputs: outlet pressure change signal, wake change signal, weight increment change signal, and motor current change signal.

4. The adaptive anti-drip filling machine according to claim 1, characterized in that: The residual liquid buffer chamber (8) is arranged around or adjacent to the outlet side of the main filling channel (6). The inlet of the back suction channel (7) is connected to the residual liquid buffer chamber (8), so that the liquid remaining on the outlet side after the main filling channel (6) stops supplying liquid first enters the residual liquid buffer chamber (8) and is then back suctioned by the negative pressure back suction assembly (11).

5. The adaptive anti-drip filling machine according to claim 1, characterized in that: The end seal reset component (10) includes an elastic sealing ring or a resettable sealing component surrounding the outlet of the main filling channel (6). After the shut-off valve assembly (9) is closed, the end seal reset component (10) fits against the outlet edge of the main filling channel (6) under the drive of the pump valve drive module (15) or its own reset action.

6. The adaptive anti-drip filling machine according to claim 1, characterized in that: The control box (14) is equipped with a controller (403), a sampling conditioning and amplification unit (410), and a pump and valve drive unit (411). The sampling conditioning and amplification unit (410) receives the sampling signal output by the sensor group and sends it to the controller (403). The pump and valve drive unit (411) receives the control command output by the controller (403) and outputs drive signals to the servo metering pump actuator (413), the shut-off valve actuator (414), the negative pressure back suction actuator (415), and the end sealing actuator (416). The servo metering pump actuator (413), the shut-off valve actuator (414), the negative pressure back suction actuator (415), and the end sealing actuator (416) correspond to the servo metering pump (4), the shut-off valve assembly (9), the negative pressure back suction assembly (11), and the end sealing reset component (10), respectively.

7. The adaptive anti-drip filling machine according to claim 6, characterized in that: The sampling conditioning and amplification unit (410) is equipped with a sampling current limiting resistor (408) and a filter capacitor (409) in the front stage. The sampling current limiting resistor (408) and the filter capacitor (409) are used to limit transient impacts and filter out high-frequency disturbances before the status signal enters the controller (403). A pump drive switch (412) is provided between the pump valve drive unit (411) and the servo metering pump actuator (413).

8. The adaptive anti-drip filling machine according to claim 1, characterized in that: It also includes a vision inspection unit (16) and a container positioning fixture (17). The vision inspection unit (16) is arranged facing the liquid outlet of the filling head housing (5) or the bottle mouth area of ​​the container to be filled (18). The vision inspection unit (16) is connected to the controller (403) through a vision inspection signal input interface (417) to input the bottle mouth image status to the controller (403). The bottle mouth image status serves as an auxiliary input for the residual liquid risk level. The container positioning fixture (17) is set on the conveying positioning table (2) and defines the bottle mouth position of the container to be filled (18).

9. A control method for an adaptive anti-drip filling machine based on claim 1, characterized in that: The process includes collecting the status signal output by the sensor group at the end of the filling stage; extracting the residual liquid status characteristics from the status signal, wherein the residual liquid status characteristics include at least two of the following: pressure decay trend, wake change trend, weight increment change trend, and motor current change trend. The controller determines the risk level of the residual liquid based on the residual liquid state characteristics; Based on the residual liquid risk level, the system generates a deceleration command for the servo metering pump (4), an early valve closing command for the shut-off valve assembly (9), a back suction pulse command for the negative pressure back suction assembly (11), and a sealing reset command for the end seal reset component (10); and outputs the above commands to the corresponding actuators through the pump valve drive module (15).

10. The control method according to claim 9, characterized in that: After outputting the back suction pulse command and the seal reset command, the controller records at least two types of feedback states among the pressure signal, flow signal, weight signal and current signal at the end of this filling stage, and updates at least one of the pump deceleration advance, valve closing advance, back suction pulse parameter and seal reset timing at the end of the next filling stage according to the feedback states.

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