Method and system for controlling the filling level

Abstract

The application provides a filling amount control method and a control system, wherein the filling amount control method comprises the following steps: obtaining a target filling amount; selecting an electronic cam curve matched with the target filling amount, wherein a main shaft of the electronic cam curve is a main motor shaft, a from shaft is a piston motor shaft, and the electronic cam curve at least comprises a material suction cam curve segment and a material injection cam curve segment in sequence; and controlling the piston motor to move according to the electronic cam curve, wherein the piston motor drives the filling piston to move in a first direction according to the material suction cam curve segment to suck the target filling amount of material from a material storage cylinder into a piston cylinder, and drives the filling piston to move in the opposite direction of the first direction according to the material injection cam curve segment to push the target filling amount of material from the piston cylinder into a filling container, wherein the first direction is parallel to an inner cavity side wall of the piston cylinder.

Description

Technical Field

[0001] This application relates to the field of filling, and more particularly to a method and control system for controlling the filling volume. Background Technology

[0002] 1. When fine-tuning the filling volume is required, workers will rotate a nut on the connecting rod to change the length of the connecting rod. This changes the stroke of the piston, thus altering the volume of liquid discharged in one working cycle. This process often requires multiple adjustments, weighing, readjustment, and reweighing to achieve the desired result.

[0003] 2. When the filling function is achieved by a mechanical cam, the piston cannot achieve a completely parallel movement with the side wall of the cavity, which causes the connecting rod to vibrate and the piston to wear. As the filling time of the equipment increases, aging and leakage will occur. Summary of the Invention

[0004] In view of this, this application provides a method and control system for controlling the filling volume, so as to at least partially solve the above problems.

[0005] According to a first aspect of the embodiments of this application, a method for controlling the filling volume is provided for a metering pump filling machine, the metering pump filling machine including a main motor and a piston motor for driving a filling piston, the method for controlling the filling volume includes the following steps:

[0006] Obtain the target filling volume;

[0007] Select an electronic cam curve that matches the target filling volume, wherein the main axis of the electronic cam curve is the main motor shaft, the slave axis is the piston motor shaft, and the electronic cam curve includes at least one suction cam curve segment and one injection cam curve segment in sequence.

[0008] The piston motor is controlled to move according to the electronic cam curve, wherein the piston motor drives the filling piston to move along a first direction according to the suction cam curve segment to suck the target filling amount of material from the storage cylinder into the piston cylinder, and drives the filling piston to move in the opposite direction of the first direction according to the injection cam curve segment to push the target filling amount of material from the piston cylinder into the filling container, wherein the first direction is parallel to the inner cavity sidewall of the piston cylinder.

[0009] Optionally, the electronic cam curve has a first control point C1 and a second control point C2. The first control point C1 and the second control point C2 divide the electronic cam curve into a suction cam curve segment, a stationary segment, and an injection cam curve segment in sequence. The ordinate of the first control point and the ordinate of the second control point are equal. The stationary segment is a horizontal line segment. The abscissa of the first control point and the abscissa of the second control point are determined based on the action rhythm of the filling process.

[0010] Optionally, the method for controlling the filling volume further includes the following steps:

[0011] Based on the correspondence between filling volume and piston position Δd, the electronic cam curve corresponding to each target filling volume is planned, wherein the piston position Δd is the distance between the end of the filling piston that is close to the bottom wall of the piston cylinder and the bottom wall of the piston cylinder.

[0012] Optionally, the step of planning the electronic cam curve corresponding to each target filling volume based on the correspondence between the filling volume and the piston position Δd includes the following sub-steps:

[0013] Obtain the radius r of the filling piston, and based on the target filling volume and the radius r, obtain the ordinate values ​​y of the first control point C1 and the second control point C2. con ;

[0014] Based on the ordinate values ​​y of the first control point C1 and the second control point C2 con and the x-coordinate of the first control point C1 c1 The x-coordinate of the second control point C2 c2 The coordinates C1(x) of the first control point are obtained. c1 ,y con ) and the coordinates C2(x) of the second control point c2 ,y con );

[0015] Obtain the starting coordinates of the suction cam curve segment and the ending coordinates of the injection cam curve segment;

[0016] The coordinates of the starting point of the suction cam curve segment and the coordinates of the first control point C1(x) c1 ,y con Interpolation is performed between ) to obtain the suction cam curve segment; the coordinates C2(x) of the second control point are used to interpolate the curve segment. c2 ,y con The injection cam curve segment is obtained by interpolating between the endpoint coordinates of the injection cam curve segment and the endpoint coordinates of the first control point C1(x). c1 ,y con), the coordinates of the second control point C2(x) c2 ,y con The cam curve segment of the stationary section is obtained.

[0017] Optionally, the step of planning the electronic cam curve corresponding to each target filling volume based on the correspondence between the filling volume and the piston position Δd includes the following sub-steps:

[0018] A kinematic model of a mechanical cam driving a filling piston is established, wherein the mechanical cam includes a mechanical cam body and a connecting rod for connecting the mechanical cam body and the filling piston;

[0019] Based on the kinematic model, the coordinates of several key points of the suction cam curve segment and the injection cam curve segment are obtained. The key points of the suction cam curve segment include at least the starting point of the suction cam curve segment and the first control point C1, and the key points of the injection cam curve segment include at least the ending point of the injection cam curve segment and the second control point C2.

[0020] The electronic cam curve is obtained based on the coordinates of the key points.

[0021] Optionally, the step of obtaining the coordinates of several key points of the suction cam curve segment and the injection cam curve segment based on the kinematic model further includes:

[0022] Based on the kinematic model, a functional relationship is obtained to characterize the relationship between the piston position Δd and the connecting rod length L and the connecting rod angle a, wherein the connecting rod angle a is the angle between the length direction of the connecting rod and the second direction, and the second direction is perpendicular to the first direction;

[0023] Obtain the conversion coefficient h between the angle φ of the mechanical cam body and the angle a of the connecting rod;

[0024] Based on the conversion coefficient h and the functional relationship, the coordinates of several key points of the suction cam curve segment and the injection cam curve segment are obtained.

[0025] Optionally, the method for controlling the filling volume further includes the following steps:

[0026] The electronic cam curve is first verified using a verification method that differs from the planning method for the electronic cam curve.

[0027] Optionally, the method for controlling the filling volume further includes the following steps:

[0028] The electronic cam curve is then validated a second time based on the actual filling volume, which includes the following sub-steps:

[0029] Obtain the actual filling volume;

[0030] The actual filling volume is compared with the target filling volume. If the actual filling volume does not fall within the threshold range of the target filling volume, the electronic cam curve is adjusted according to the difference between the actual filling volume and the target filling volume.

[0031] Optionally, the main motor and the piston motor are servo motors; or, the main motor is a three-phase asynchronous motor, the piston motor is a servo motor, and the quantitative pump filling machine further includes an encoder, which is communicatively connected to the shaft of the main motor.

[0032] According to a second aspect of the embodiments of this application, a filling volume control system is provided. The metering pump filling machine includes a main motor and a piston motor for driving the filling piston. The filling volume control system includes:

[0033] The acquisition module is used to obtain the target filling volume;

[0034] The selection module is used to select an electronic cam curve that matches the target filling volume. The main axis of the electronic cam curve is the main motor shaft, and the slave axis is the piston motor shaft. The electronic cam curve includes at least one suction cam curve segment and one injection cam curve segment in sequence.

[0035] A control module is configured to control the movement of the piston motor according to the electronic cam curve, wherein the piston motor drives the filling piston to move along a first direction according to the suction cam curve segment to suck the target filling amount of material from the storage cylinder into the piston cylinder, and drives the filling piston to move in the opposite direction of the first direction according to the injection cam curve segment to push the target filling amount of material from the piston cylinder into the filling container, wherein the first direction is parallel to the inner cavity sidewall of the piston cylinder.

[0036] The filling volume control method and control system provided in this application use a piston motor to drive the filling piston to reciprocate along a direction parallel to the inner wall of the piston cylinder. This ensures that the movement direction of the filling piston is completely parallel to the inner wall, avoiding pressure on the inner wall and effectively preventing leakage caused by wear and deformation of the filling piston, thus improving production efficiency. Furthermore, the filling volume control method of this application adjusts the filling volume by selecting an electronic cam curve that matches the target filling volume. Its operation is precise and simple, further improving production efficiency and the accuracy of filling volume control. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of a filling piston driven by a mechanical cam.

[0038] Figure 2 A simplified structural diagram of a filling volume control system, which is an exemplary embodiment of this application.

[0039] Figure 3 This is a flowchart illustrating the filling volume control method according to an embodiment of this application.

[0040] Figure 4 A flowchart of a method for controlling the filling amount, which is another exemplary embodiment of this application.

[0041] Figure 5 This is a schematic diagram of the electronic cam curve according to an embodiment of this application.

[0042] List of reference numerals in the attached diagram:

[0043] 11: Mechanical Cam Body

[0044] 12: Linkage;

[0045] 13: Piston cylinder;

[0046] 14: Feed check valve;

[0047] 15: Discharge check valve;

[0048] 16: Filling piston;

[0049] 17: Length adjustment device

[0050] 20: Filling containers;

[0051] 31: Piston motor;

[0052] 32: Synchronous belt;

[0053] A1: First direction;

[0054] A2: Second direction;

[0055] 511: 250ml electronic cam curve;

[0056] 512: 500ml electronic cam curve;

[0057] 513: 1000ml electronic cam curve;

[0058] 52: Select the electronic cam curve according to the specifications of the filling container;

[0059] 53: The piston motor drives the filling piston to move according to the selected electronic cam curve to achieve material suction and injection;

[0060] 54: Weighing to obtain the actual filling volume;

[0061] 55: Fine-tune the electronic cam curve based on the difference between the actual filling volume and the target filling volume;

[0062] 56: Qualified product. Detailed Implementation

[0063] To enable those skilled in the art to better understand the technical solutions in the embodiments of this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art should fall within the protection scope of the embodiments of this application.

[0064] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Where there is no conflict between the embodiments, the following embodiments and features can be combined with each other. The steps in the following method embodiments are for illustrative purposes only and are not intended to limit the invention.

[0065] A quantitative pump filling machine is a device that uses pressure to fill containers. Figure 1 This is a schematic diagram illustrating the principle of quantitative filling in a conventional quantitative pump filling machine. Figure 1 As shown, the main motor M rotates, driving the mechanical cam body 11 to rotate. Each time a package is filled, the mechanical cam body 11 rotates one revolution, and the filling piston 16 moves up and down once. This, combined with the cooperation of the inlet check valve 14 and the outlet check valve 15, completes the material suction and pushing process (similar to a syringe). The pushed material is then fed into the filling container 20 through the pipeline and filling head, and then the filling container 20 is sealed, thus completing the filling process. During production, the filling volume needs to be adjusted according to the volume of the filling container 20. In the existing technology, the filling volume is adjusted by the operator rotating a length adjustment device 17 on the connecting rod 12 to change the length of the connecting rod 12. This changes the stroke of the filling piston 16, thus changing the volume of liquid discharged in one working cycle. However, since there is no direct linear relationship between the change in the length of the connecting rod 12 and the change in the volume of discharged liquid, a weighing device is needed after each adjustment to check if the adjustment target has been achieved. This process often requires multiple adjustments, weighing, readjustments, and re-weighings to reach the target. Therefore, this method heavily relies on the operator's experience, resulting in low production efficiency. Furthermore, as... Figure 1As shown, the force applied to the piston by the mechanical cam body 11 through the connecting rod 12 has an angle with the axial direction of the filling piston 16. Therefore, the direction of piston movement is not parallel to the side wall of the piston cylinder 13, and the angle between them is constantly changing. This causes the filling piston 16 to generate additional squeezing force on the side wall of the cavity, and the magnitude and direction of this squeezing force are also constantly changing. This aggravates the wear and deformation of the filling piston 16, and often leads to leakage. This not only increases the product defect rate, but also requires frequent piston replacement, increases machine downtime for maintenance, and seriously affects production efficiency.

[0066] In view of the various problems in the prior art, the embodiments of this application provide a filling volume control method and control system to at least partially solve the above problems.

[0067] The filling volume control schemes provided in the various embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0068] Methods for controlling filling volume

[0069] Figure 3 This is a flowchart of a filling volume control method 100 for a quantitative pump filling machine according to an exemplary embodiment of this application. Figure 2 An example of a metering pump filling machine is shown.

[0070] like Figure 2 As shown, the filling piston 16 is driven by the piston motor 31, and the rotational motion of the piston motor 31 is converted into the periodic reciprocating motion of the filling piston along the inner cavity sidewall parallel to the piston cylinder 13 by the synchronous belt 32.

[0071] like Figure 3 As shown, method 100 mainly includes the following steps:

[0072] S102. Obtain the target filling volume V_set;

[0073] Target filling volume is usually expressed in volume (e.g., liters, milliliters) or weight (e.g., grams, kilograms). Different sizes of packaging containers correspond to specific target filling volumes. For example, a 250ml milk carton has a target filling volume of 250ml.

[0074] S104. Select an electronic cam curve that matches the target filling volume V_set, wherein the main axis of the electronic cam curve is the main motor axis, the slave axis is the piston motor axis, and the electronic cam curve includes at least one suction cam curve segment and one injection cam curve segment in sequence.

[0075] The position of the master axis of the electronic cam curve uniquely corresponds to the position of the slave axis. As the master axis moves, the position of the slave axis also changes, thus maintaining a specific cam-like relationship between the master and slave axes. In this application, the master axis is the shaft of the main motor, and the slave axis is the shaft of the piston motor. After the filling machine starts, the main motor rotates at a set speed, and the piston motor drives the filling piston to change position according to the electronic cam curve, following the change in the master axis position, thereby achieving precise control and flexible adjustment of the filling volume.

[0076] Both the main shaft and the driven shaft of the electronic cam are rotary shafts. Within one motion cycle of the electronic cam, the filling piston completes one reciprocating motion, thus achieving one filling operation.

[0077] In some implementations, the main motor shaft is a virtual shaft.

[0078] In other implementations, the main motor shaft is a physical shaft.

[0079] The control of gable-top bag filling is more complex. A gable-top bag filling machine consists of systems for carton making, filling, transmission, and sealing. To improve production efficiency during the filling process, all systems and devices need to operate synchronously and collaboratively. For example, while suctioning material, actions such as heating and lifting the bottom of the carton, bottom folding, carton detection, and top heating and folding are required to complete carton making. Before filling, the empty carton needs to be transported to the preset filling position. During filling, the gable-top bag needs to remain stationary at the filling position, and after filling, the carton needs to be transported to the next station. Therefore, electronic cams can be used to synchronously control the various systems of the gable-top bag filling machine. The main motor shaft is the master shaft, and the other motor shafts requiring synchronous control are slave shafts. The electronic cam curves of each slave shaft are used to make them follow the movement of the master shaft, thereby achieving synchronous control between the slave shafts and enabling the filling machine to operate in a production line manner according to the production rhythm.

[0080] Optionally, the electronic cam curve has a first control point C1 and a second control point C2. The first control point C1 and the second control point C2 divide the electronic cam curve into a suction cam curve segment, a stationary segment, and an injection cam curve segment in sequence. The ordinate of the first control point and the ordinate of the second control point are equal. The stationary segment is a horizontal line segment. The abscissa of the first control point and the abscissa of the second control point are determined based on the action rhythm of the filling process.

[0081] Figure 5 This refers to the electronic cam curve corresponding to the target filling volume V1. For example... Figure 5As shown, the horizontal line segment between the first control point C1 and the second control point C2 is a stationary segment. The ordinate value of any point in the stationary segment is equal, meaning that the cam piston remains stationary in the stationary segment, thus forming a motion buffer zone between the suction segment and the filling segment. Since preparatory processes such as box making and packaging container conveying need to be completed before filling, and these preparatory processes take a long time, the stationary segment can be set up to utilize the suction cam curve segment and the stationary segment to complete the preparatory processes before filling, thus satisfying the filling process.

[0082] S106. The piston motor is controlled to move according to the electronic cam curve, wherein the piston motor 31 drives the filling piston to move along the first direction A1 according to the suction cam curve segment to suck the target filling amount of material from the storage cylinder into the piston cylinder 13, and drives the filling piston to move in the opposite direction of the first direction A1 according to the injection cam curve segment to push the target filling amount of material from the piston cylinder 13 into the filling container 20, wherein the first direction A1 is parallel to the inner cavity sidewall of the piston cylinder 13.

[0083] The filling volume control method of this application uses a piston motor to drive the filling piston to reciprocate along a direction parallel to the inner wall of the piston cylinder 13. This ensures that the movement direction of the filling piston is completely parallel to the inner wall, avoiding pressure on the inner wall and effectively preventing leakage caused by wear and deformation of the filling piston, thus improving production efficiency. Furthermore, the filling volume control method of this application adjusts the filling volume by selecting an electronic cam curve that matches the target filling volume. This method is precise and easy to operate, further improving production efficiency and the accuracy of filling volume control.

[0084] Optionally, the method for controlling the filling volume further includes the following steps:

[0085] S101. Based on the correspondence between the filling volume and the piston position Δd, plan the electronic cam curve corresponding to each target filling volume, wherein the piston position Δd is the distance between the end of the filling piston 16 closest to the bottom wall of the piston cylinder 13 and the bottom wall of the piston cylinder 13. Figure 2 As shown.

[0086] In one implementation, method 200 is used to plan the electronic cam curve corresponding to each target filling volume, method 200 including:

[0087] S201. Obtain the radius r of the filling piston, and obtain the ordinate values ​​y of the first control point C1 and the second control point C2 based on the target filling volume and the radius r. con ;

[0088] Let the target filling volume be V_set. The piston position Δd corresponding to the target filling volume can be obtained according to Formula 2-1.

[0089]

[0090] Based on the piston position Δd corresponding to the target filling volume, the position value of the piston motor can be obtained. That is, based on the piston position Δd, the ordinate values ​​y of the first control point C1 and the second control point C2 can be obtained. con .

[0091] S202, based on the ordinate values ​​y of the first control point C1 and the second control point C2 con and the x-coordinate of the first control point C1 c1 The x-coordinate of the second control point C2 c2 The coordinates C1(x) of the first control point are obtained. c1 ,y con ) and the coordinates C2(x) of the second control point c2 ,y con );

[0092] S203. Obtain the starting coordinates of the suction cam curve segment and the ending coordinates of the injection cam curve segment;

[0093] In some implementations, such as Figure 5 The electronic cam curve shown in the figure has the starting point of the suction cam curve segment as the starting point C0(x) of the entire electronic cam curve. c0 The endpoint of the injection cam curve segment is the endpoint Cn(x) of the entire electronic cam curve. cn ,y n ).

[0094] In other implementations, the entire electronic cam curve can be divided into more intervals using multiple control points.

[0095] S204, the starting coordinates of the suction cam curve segment and the coordinates of the first control point C1(x) c1 ,y con Interpolation is performed between ) to obtain the suction cam curve segment; the coordinates C2(x) of the second control point are used to interpolate the curve segment. c2 ,y con The injection cam curve segment is obtained by interpolating between the endpoint coordinates of the injection cam curve segment and the endpoint coordinates of the first control point C1(x). c1 ,y con ), the coordinates of the second control point C2(x) c2 ,y con The cam curve segment of the stationary section is obtained.

[0096] In some implementations, a cubic polynomial is used to interpolate between the start and end coordinates of the suction cam curve segment and the injection cam curve segment.

[0097] In another embodiment, method 300 is used to plan the electronic cam curve corresponding to each target filling volume, method 300 including:

[0098] S301. Establish a kinematic model of a mechanical cam driving a filling piston. The mechanical cam includes a mechanical cam body 11 and a connecting rod 12 for connecting the mechanical cam body 11 and the filling piston.

[0099] S302. Based on the kinematic model, obtain the coordinates of several key points of the suction cam curve segment and the injection cam curve segment. The key points of the suction cam curve segment include at least the starting point of the suction cam curve segment and the first control point C1, and the key points of the injection cam curve segment include at least the ending point of the injection cam curve segment and the second control point C2.

[0100] Optionally, step S302 includes the following sub-steps:

[0101] S3021. Based on the kinematic model, a functional relationship is obtained to characterize the relationship between the piston position Δn and the length L of the connecting rod 12 and the angle a of the connecting rod 12. The position value of the piston motor (the position value from the shaft, i.e., the ordinate of the electronic cam curve) can be obtained from the piston position Δn, as shown in Formula 3-1. The angle a of the connecting rod 12 is the angle between the length direction of the connecting rod 12 and the second direction A2, where the second direction A2 is perpendicular to the first direction A1. Figure 1 As shown;

[0102] △n=L×sina3-1

[0103] S3022. Obtain the conversion coefficient h between the angle φ of the mechanical cam body 11 and the angle a of the connecting rod 12. According to formula 3-2, the angle a of the connecting rod 12 can be converted into the angle φ of the main motor shaft. The angle φ of the main motor shaft is the abscissa of the electronic cam curve.

[0104] a=φ×h3-2

[0105] S3023. Based on the conversion coefficient h and the functional relationship 3-1, the coordinates of several key points of the suction cam curve segment and the injection cam curve segment are obtained.

[0106] Depend on Figure 1It can be seen that the mechanical cam body 11 pushes the filling piston through the connecting rod 12, and the angle α of the connecting rod 12 has a unique correspondence with the cam angle φ of the mechanical cam. Therefore, through formulas 3-1 and 3-2, several correspondences between the angle φ of the mechanical cam body 11 and the piston position Δn can be obtained, where the angle φ of the mechanical cam body 11 is the abscissa value of the electronic cam curve, and the ordinate value of the electronic cam curve can be obtained according to the piston position Δn, thus obtaining the coordinates of several key points of the suction cam curve segment and the injection cam curve segment.

[0107] S303. Obtain the electronic cam curve based on the coordinates of the key points.

[0108] The electronic cam curve is obtained by using the coordinates of multiple key points, resulting in higher accuracy. Using the electronic cam curve planned by Method 300, the filling process is precisely guided and filled step-by-step according to the correspondence between the angle φ of the mechanical cam body 11 and the piston position △n, avoiding liquid splashing.

[0109] In one embodiment, the filling volume control method further includes step S107, performing a first verification of the electronic cam curve using a verification method, wherein the verification method is different from the planning method of the electronic cam curve.

[0110] For example, if method 200 is used to plan the electronic cam curve, then a method other than method 200 is used to verify the electronic cam curve, such as method 300. If method 300 is used to plan the electronic cam curve, then a method other than method 300 is used to verify the electronic cam curve, such as method 200.

[0111] By using a different planning method than the electronic cam curve to perform the first verification of the electronic cam curve, the accuracy of the electronic cam curve is improved, which in turn improves the control precision of the filling volume, reduces subsequent debugging, and thus improves filling efficiency and saves production costs.

[0112] In one embodiment, the filling volume control method further includes step S109, which involves performing a second verification of the electronic cam curve based on the actual filling volume. Step S109 includes the following sub-steps:

[0113] S1091. Obtain the actual filling volume;

[0114] S1092. Compare the actual filling volume with the target filling volume. If the actual filling volume does not fall within the threshold range of the target filling volume, adjust the electronic cam curve according to the difference between the actual filling volume and the target filling volume.

[0115] Figure 4A flowchart illustrating one method of controlling the filling volume according to this embodiment is shown.

[0116] like Figure 4 As shown, firstly, an electronic cam curve is selected based on the target filling volume corresponding to the specifications of the filling container. The piston motor drives the filling piston to move according to the selected electronic cam curve to achieve material suction and injection. Then, the filling container after filling is weighed to obtain the actual filling volume. If the actual filling volume does not fall within the threshold range of the target filling volume, the electronic cam curve is fine-tuned based on the difference between the actual filling volume and the target filling volume.

[0117] Based on the above embodiments, in one implementation, the main motor and the piston motor are servo motors.

[0118] The servo motor is equipped with an encoder, which enables precise position control based on the electronic cam curve.

[0119] In another embodiment, the main motor is a three-phase asynchronous motor, the piston motor is a servo motor, and the quantitative pump filling machine further includes an encoder, which is communicatively connected to the shaft of the main motor.

[0120] The main motor has a large power output, and a three-phase asynchronous motor is used as the main motor because it is inexpensive and has high performance.

[0121] Filling volume control system

[0122] This application also provides a filling volume control system for a metering pump filling machine, the metering pump filling machine including a main motor and a piston motor for driving the filling piston, the filling volume control system including:

[0123] The acquisition module is used to obtain the target filling volume;

[0124] The selection module is used to select an electronic cam curve that matches the target filling volume. The main axis of the electronic cam curve is the main motor shaft, and the slave axis is the piston motor shaft. The electronic cam curve includes at least one suction cam curve segment and one injection cam curve segment in sequence.

[0125] A control module is configured to control the movement of the piston motor according to the electronic cam curve, wherein the piston motor drives the filling piston to move along a first direction A1 according to the suction cam curve segment to suck the target filling amount of material from the storage cylinder into the piston cylinder 13, and drives the filling piston to move in the opposite direction of the first direction A1 according to the injection cam curve segment to push the target filling amount of material from the piston cylinder 13 into the filling container, wherein the first direction A1 is parallel to the inner cavity sidewall of the piston cylinder 13.

[0126] Optionally, the electronic cam curve has a first control point C1 and a second control point C2. The first control point C1 and the second control point C2 divide the electronic cam curve into a suction cam curve segment, a stationary segment, and an injection cam curve segment in sequence. The ordinate of the first control point and the ordinate of the second control point are equal. The stationary segment is a horizontal line segment. The abscissa of the first control point and the abscissa of the second control point are determined based on the action rhythm of the filling process.

[0127] Optionally, the filling volume control method further includes a cam curve planning module, which is used to plan the electronic cam curve corresponding to each target filling volume according to the correspondence between the filling volume and the piston position Δd, wherein the piston position Δd is the distance between the end of the filling piston close to the bottom wall of the piston cylinder 13 and the bottom wall of the piston cylinder 13.

[0128] In one implementation, the cam curve planning module includes the following sub-modules:

[0129] The control point coordinate calculation submodule is used to obtain the radius r of the filling piston, and to obtain the ordinate values ​​y of the first control point C1 and the second control point C2 based on the target filling volume and the radius r. con ; and based on the ordinate values ​​y of the first control point C1 and the second control point C2 con and the x-coordinate of the first control point C1 c1 The x-coordinate of the second control point C2 c2 The coordinates C1(x) of the first control point are obtained. c1 ,y con ) and the coordinates C2(x) of the second control point c2 ,y con );

[0130] The acquisition module is used to acquire the starting coordinates of the suction cam curve segment and the ending coordinates of the injection cam curve segment;

[0131] The interpolation submodule is used to determine the starting coordinates of the feed cam curve segment and the coordinates C1(x) of the first control point. c1 ,y con Interpolation is performed between ) to obtain the suction cam curve segment; the coordinates C2(x) of the second control point are used to interpolate the curve segment. c2 ,y con The injection cam curve segment is obtained by interpolating between the endpoint coordinates of the injection cam curve segment and the endpoint coordinates of the first control point C1(x). c1 ,y con ), the coordinates of the second control point C2(x) c2 ,y conThe cam curve segment of the stationary section is obtained.

[0132] In another implementation, the cam curve planning module includes the following sub-modules:

[0133] The model building module is used to build a kinematic model of a mechanical cam driving a filling piston. The mechanical cam includes a mechanical cam body 11 and a connecting rod 12 for connecting the mechanical cam body 11 and the filling piston.

[0134] The key point coordinate calculation module is used to obtain the coordinates of several key points of the suction cam curve segment and the injection cam curve segment according to the kinematic model. The key points of the suction cam curve segment include at least the starting point of the suction cam curve segment and the first control point C1, and the key points of the injection cam curve segment include at least the ending point of the injection cam curve segment and the second control point C2.

[0135] An electronic cam curve generation module is used to obtain the electronic cam curve based on the coordinates of the key points.

[0136] Optionally, the key point coordinate calculation module is used to obtain a functional relationship based on the kinematic model to characterize the relationship between the piston position Δd and the length L of the connecting rod 12 and the angle a of the connecting rod 12, wherein the angle a of the connecting rod 12 is the angle between the length direction of the connecting rod 12 and the second direction A2, and the second direction A2 is perpendicular to the first direction A1.

[0137] Obtain the conversion coefficient h between the angle φ of the mechanical cam body 11 and the angle a of the connecting rod 12;

[0138] Based on the conversion coefficient h and the functional relationship, the coordinates of several key points of the suction cam curve segment and the injection cam curve segment are obtained.

[0139] Optionally, the filling volume control system further includes a first verification module, which is used to perform a first verification of the electronic cam curve using a verification method, wherein the verification method is different from the planning method of the electronic cam curve.

[0140] Optionally, the filling volume control system further includes a second verification module, which is used to perform a second verification of the electronic cam curve based on the actual filling volume. Specifically, the module obtains the actual filling volume; compares the actual filling volume with the target filling volume; and if the actual filling volume does not fall within the threshold range of the target filling volume, adjusts the electronic cam curve based on the difference between the actual filling volume and the target filling volume.

[0141] In one embodiment, the main motor and the piston motor are servo motors.

[0142] In another embodiment, the main motor is a three-phase asynchronous motor, the piston motor is a servo motor, and the quantitative pump filling machine further includes an encoder, which is communicatively connected to the shaft of the main motor.

[0143] electronic devices

[0144] This application also provides an electronic device. The electronic device provided in this application includes: a processor, a communications interface, memory, and a bus. Wherein:

[0145] The processor, communication interface, and memory communicate with each other via a bus.

[0146] A communication interface is used to communicate with other electronic devices or servers.

[0147] The processor is used to execute programs, specifically the relevant steps in the above-described embodiments of the filling volume control method.

[0148] Specifically, the program may include program code, which includes computer operation instructions.

[0149] The processor may be a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of this application. The one or more processors included in the smart device may be processors of the same type, such as one or more CPUs; or they may be processors of different types, such as one or more CPUs and one or more ASICs.

[0150] Memory is used to store programs. Memory may include high-speed RAM, and may also include non-volatile memory, such as at least one disk drive.

[0151] Specifically, the program can be used to cause the processor to execute the filling amount control method in any of the foregoing embodiments.

[0152] The specific implementation of each step in the program can be found in the corresponding steps and units described in the above-described embodiments of the filling volume control method, and will not be repeated here. Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working process of the equipment and modules described above can be referred to the corresponding process descriptions in the aforementioned method embodiments, and will not be repeated here.

[0153] Computer-readable storage media

[0154] This application also provides a computer-readable storage medium storing instructions for causing a machine to perform a device filling quantity control method as described herein. Specifically, a system or apparatus equipped with a storage medium storing software program code that implements the functions of any of the embodiments described above, and enabling the computer (or CPU or MPU) of the system or apparatus to read and execute the program code stored in the storage medium.

[0155] In this case, the program code read from the storage medium can itself implement the function of any of the above embodiments, and therefore the program code and the storage medium storing the program code constitute part of this application.

[0156] Examples of storage media used to provide program code include floppy disks, hard disks, magneto-optical disks, optical disks (such as CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD+RW), magnetic tapes, non-volatile memory cards, and ROMs. Alternatively, program code can be downloaded from a server computer via a communication network.

[0157] Computer program products

[0158] This application also provides a computer program product, including computer instructions that instruct a computing device to perform any corresponding operation in the above-described plurality of method embodiments.

[0159] It should be noted that, depending on the implementation needs, the various components / steps described in the embodiments of this application can be broken down into more components / steps, or two or more components / steps or parts of the operation of components / steps can be combined into new components / steps to achieve the purpose of the embodiments of this application.

[0160] The methods described in the embodiments of this application can be implemented in hardware, firmware, or as software or computer code that can be stored in a recording medium (such as a CD-ROM, RAM, floppy disk, hard disk, or magneto-optical disk), or as computer code downloaded over a network that is originally stored in a remote recording medium or a non-transitory machine-readable medium and will be stored in a local recording medium. Thus, the methods described herein can be processed by software stored on a recording medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware (such as an ASIC or FPGA). It is understood that the computer, processor, microprocessor controller, or programmable hardware includes storage components (e.g., RAM, ROM, flash memory, etc.) capable of storing or receiving software or computer code that, when accessed and executed by the computer, processor, or hardware, implements the methods described herein. Furthermore, when a general-purpose computer accesses code used to implement the methods shown herein, the execution of the code transforms the general-purpose computer into a dedicated computer for executing the methods shown herein.

[0161] It should be noted that not all steps and modules in the above processes and system structure diagrams are mandatory; some steps or modules can be omitted as needed. The execution order of each step is not fixed and can be adjusted as required. The system structure described in the above embodiments can be a physical structure or a logical structure. That is, some modules may be implemented by the same physical entity, or some modules may be implemented by multiple physical entities, or they may be jointly implemented by certain components in multiple independent devices.

[0162] In this patent application, nouns and pronouns relating to people are not limited to specific genders.

[0163] In the above embodiments, the hardware modules can be implemented mechanically or electrically. For example, a hardware module may include permanent dedicated circuitry or logic (such as a dedicated processor, FPGA, or ASIC) to perform the corresponding operations. The hardware module may also include programmable logic or circuitry (such as a general-purpose processor or other programmable processor), which can be temporarily configured by software to perform the corresponding operations. The specific implementation method (mechanical, dedicated permanent circuitry, or temporarily configured circuitry) can be determined based on cost and time considerations.

[0164] The present invention has been shown and described in detail above with reference to the accompanying drawings and preferred embodiments. However, the present invention is not limited to these disclosed embodiments. Based on the above multiple embodiments, those skilled in the art will know that more embodiments of the present invention can be obtained by combining the code review methods in the different embodiments above. These embodiments are also within the protection scope of the present invention.

Claims

1. A method for controlling filling volume, used in a quantitative pump filling machine, characterized in that, The quantitative pump filling machine includes a main motor and a piston motor (31) for driving the filling piston. The method for controlling the filling volume includes the following steps: Obtain the target filling volume; Select an electronic cam curve that matches the target filling volume, wherein the main axis of the electronic cam curve is the main motor shaft, the slave axis is the piston motor shaft, and the electronic cam curve includes at least one suction cam curve segment and one injection cam curve segment in sequence. The piston motor (31) is controlled to move according to the electronic cam curve, wherein the piston motor (31) drives the filling piston to move along a first direction according to the suction cam curve segment to suck the target filling amount of material from the storage cylinder into the piston cylinder, and drives the filling piston to move in the opposite direction of the first direction according to the injection cam curve segment to push the target filling amount of material from the piston cylinder into the filling container, wherein the first direction is parallel to the inner cavity sidewall of the piston cylinder; The electronic cam curve has a first control point C1 and a second control point C2. The first control point C1 and the second control point C2 sequentially divide the electronic cam curve into a suction cam curve segment, a stationary segment, and an injection cam curve segment. The ordinate of the first control point C1 and the ordinate of the second control point C2 are equal. The stationary segment is a horizontal line segment. The abscissas of the first control point C1 and the second control point C2 are determined based on the action cycle of the filling process. The electronic cam curve is obtained based on the following method: Based on the correspondence between filling volume and piston position Δd, the electronic cam curve corresponding to each target filling volume is planned, wherein the piston position Δd is the distance between the end of the filling piston closest to the bottom wall of the piston cylinder and the bottom wall of the piston cylinder; it includes the following sub-steps: Obtain the radius r of the filling piston, and based on the target filling volume and the radius r, obtain the ordinate values ​​y of the first control point C1 and the second control point C2. con ; Based on the ordinate values ​​y of the first control point C1 and the second control point C2 con and the x-coordinate of the first control point C1 c1 The x-coordinate of the second control point C2 c2 The coordinates (x, y) of the first control point C1 are obtained. c1 , y con ) and the coordinates (x) of the second control point C2. c2 , y con ); Obtain the starting coordinates of the suction cam curve segment and the ending coordinates of the injection cam curve segment; The coordinates of the starting point of the suction cam curve segment and the coordinates of the first control point C1 (x) c1 , y con Interpolation is performed between the points to obtain the suction cam curve segment; the coordinates (x, y) of the second control point C2 are then interpolated. c2 , y con The injection cam curve segment is obtained by interpolating between the endpoint coordinates of the injection cam curve segment and the endpoint coordinates of the first control point C1; and the injection cam curve segment is obtained by interpolating between the endpoint coordinates of the first control point C1 and the endpoint coordinates of the injection cam curve segment. c1 ,y con The coordinates (x) of the second control point C2 c2 , y con The cam curve segment of the stationary section is obtained.

2. The method for controlling the filling volume as described in claim 1, characterized in that, The step of planning the electronic cam curve corresponding to each target filling volume based on the correspondence between the filling volume and the piston position Δd includes the following sub-steps: A kinematic model of a mechanical cam driving a filling piston is established, wherein the mechanical cam includes a mechanical cam body and a connecting rod for connecting the mechanical cam body and the filling piston; Based on the kinematic model, the coordinates of several key points of the suction cam curve segment and the injection cam curve segment are obtained. The key points of the suction cam curve segment include at least the starting point of the suction cam curve segment and the first control point C1, and the key points of the injection cam curve segment include at least the ending point of the injection cam curve segment and the second control point C2. The electronic cam curve is obtained based on the coordinates of the key points.

3. The method for controlling the filling volume as described in claim 2, characterized in that, The step of obtaining the coordinates of several key points of the suction cam curve segment and the injection cam curve segment based on the kinematic model further includes: Based on the kinematic model, the following parameters are obtained to characterize the piston position Δd and the connecting rod length L and connecting rod angle. The functional relationship between the links, wherein the link angles are... The angle between the length direction of the link and the second direction, where the second direction is perpendicular to the first direction; Obtain the angle of the mechanical cam body Angle with connecting rod Conversion coefficient ; Based on the conversion coefficient Using the aforementioned functional relationship, the coordinates of several key points on the suction cam curve segment and the injection cam curve segment are obtained.

4. The method for controlling the filling volume as described in any one of claims 1-3, characterized in that, The method for controlling the filling volume also includes the following steps: The electronic cam curve is first verified using a verification method that differs from the planning method for the electronic cam curve.

5. The method for controlling the filling volume as described in claim 4, characterized in that, The method for controlling the filling volume also includes the following steps: The electronic cam curve is then validated a second time based on the actual filling volume, which includes the following sub-steps: Obtain the actual filling volume; The actual filling volume is compared with the target filling volume. If the actual filling volume does not fall within the threshold range of the target filling volume, the electronic cam curve is adjusted according to the difference between the actual filling volume and the target filling volume.

6. The method for controlling the filling volume as described in claim 1, characterized in that, The main motor and the piston motor (31) are servo motors; or, the main motor is a three-phase asynchronous motor, the piston motor (31) is a servo motor, and the quantitative pump filling machine also includes an encoder, which is communicatively connected to the shaft of the main motor.

7. A filling volume control system for a metering pump filling machine, characterized in that, The quantitative pump filling machine includes a main motor and a piston motor (31) for driving the filling piston, and the filling volume control system includes: The acquisition module is used to obtain the target filling volume; The selection module is used to select an electronic cam curve that matches the target filling volume. The main axis of the electronic cam curve is the main motor shaft, and the slave axis is the piston motor shaft. The electronic cam curve includes at least one suction cam curve segment and one injection cam curve segment in sequence. A control module is used to control the movement of the piston motor (31) according to the electronic cam curve, wherein the piston motor (31) drives the filling piston to move along a first direction according to the suction cam curve segment to suck the target filling amount of material from the storage cylinder into the piston cylinder, and drives the filling piston to move in the opposite direction of the first direction according to the injection cam curve segment to push the target filling amount of material from the piston cylinder into the filling container, wherein the first direction is parallel to the inner cavity sidewall of the piston cylinder; The electronic cam curve has a first control point C1 and a second control point C2. The first control point C1 and the second control point C2 sequentially divide the electronic cam curve into a suction cam curve segment, a stationary segment, and an injection cam curve segment. The ordinate of the first control point C1 and the ordinate of the second control point C2 are equal. The stationary segment is a horizontal line segment. The abscissas of the first control point C1 and the second control point C2 are determined based on the action cycle of the filling process. The electronic cam curve is obtained based on the following method: Based on the correspondence between filling volume and piston position Δd, the electronic cam curve corresponding to each target filling volume is planned, wherein the piston position Δd is the distance between the end of the filling piston closest to the bottom wall of the piston cylinder and the bottom wall of the piston cylinder; it includes the following sub-steps: Obtain the radius r of the filling piston, and based on the target filling volume and the radius r, obtain the ordinate values ​​y of the first control point C1 and the second control point C2. con ; Based on the ordinate values ​​y of the first control point C1 and the second control point C2 con and the x-coordinate of the first control point C1 c1 The x-coordinate of the second control point C2 c2 The coordinates (x, y) of the first control point C1 are obtained. c1 , y con ) and the coordinates (x) of the second control point C2. c2 , y con ); Obtain the starting coordinates of the suction cam curve segment and the ending coordinates of the injection cam curve segment; The coordinates of the starting point of the suction cam curve segment and the coordinates of the first control point C1 (x) c1 , y con Interpolation is performed between the points to obtain the suction cam curve segment; the coordinates (x, y) of the second control point C2 are then interpolated. c2 , y con The injection cam curve segment is obtained by interpolating between the endpoint coordinates of the injection cam curve segment and the endpoint coordinates of the first control point C1; and the injection cam curve segment is obtained by interpolating between the endpoint coordinates of the first control point C1 and the endpoint coordinates of the injection cam curve segment. c1 ,y con The coordinates (x) of the second control point C2 c2 , y con The cam curve segment of the stationary section is obtained.

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