Control method, controller and injection molding machine for opening and closing mold of injection molding machine

Abstract

The application provides a control method, a controller and an injection molding machine for opening and closing a mold. The control method comprises: obtaining a control parameter for representing a position and speed relationship of a movable mold plate, and starting the movable mold plate based on the control parameter; in response to the movable mold plate performing an opening action, obtaining a historical opening end point, and judging whether the control parameter meets an expectation based on the historical opening end point; if the control parameter does not meet the expectation, correcting the control parameter, and controlling the opening action based on the corrected control parameter. The above can continuously correct the control parameter according to the actual opening action, and perform the opening action based on the corrected control parameter, thereby improving the opening accuracy of each opening action, reducing the opening deviation, and preventing the opening and closing of the mold from being prone to overshoot and incomplete opening.

Description

Technical Field

[0001] This application mainly relates to the field of injection molding machine control technology, and in particular to a control method, controller and injection molding machine for opening and closing molds of an injection molding machine. Background Technology

[0002] Injection molding machines can be used to manufacture plastic products of various shapes and sizes. Their working principle is to use the thermoplastic or thermosetting properties of plastics to melt plastic granules through heating and pressure and then inject them into a pre-designed mold. After cooling, the desired parts or products are formed.

[0003] The main functions of an injection molding machine include mold opening and mold closing. In related technologies, the problem with injection molding machines is that the moving platen is prone to overshoot during the mold opening process. This overshoot problem is particularly common after long-term use of the injection molding machine or after the user adjusts the machine's operating parameters. Summary of the Invention

[0004] The main objective of this application is to provide a control method, controller, and injection molding machine for opening and closing molds, which can improve the over-rush problem of the moving mold plate.

[0005] This application provides a control method for opening and closing molds in an injection molding machine. The injection molding machine includes a moving mold plate and a stationary mold plate. After being driven, the moving mold plate can move relative to the stationary mold plate to perform a mold closing action or a mold opening action. The control method includes: acquiring control parameters that characterize the relationship between the position and speed of the moving mold plate, and starting the moving mold plate based on the control parameters; in response to the moving mold plate performing a mold opening action, acquiring historical mold opening endpoints, and determining whether the control parameters meet expectations based on the historical mold opening endpoints; if the control parameters do not meet expectations, correcting the control parameters, and controlling the mold opening action based on the corrected control parameters.

[0006] In one possible implementation, the mold closing action includes a rapid mold closing stage, a mold holding stage, and a mold locking stage; the mold opening action includes a mold breaking stage and a rapid mold opening stage; the step of obtaining control parameters for characterizing the position and speed relationship of the moving template specifically includes: obtaining control parameters including the target position of each of the above stages and the target speed of the target position.

[0007] In one possible implementation, the mold closing action and the mold opening action further include a speed transition section connecting each stage, wherein the speed change rate of the middle part of the speed transition section is greater than the speed change rate of the beginning and end parts; wherein the control parameter further includes the speed change rate of each part in the speed transition section.

[0008] In one possible implementation, the rate of change of speed in the speed transition section is controlled to change continuously, and the rate of change of speed in the start and end portions is 0.

[0009] In one possible implementation, the control parameters include an advance deceleration distance, which is the distance between the end point of the rapid mold opening stage and the target mold opening endpoint; the step of obtaining control parameters characterizing the position and speed relationship of the moving mold platen further includes: pre-controlling the injection molding machine to repeatedly execute the mold opening action at different speeds during the rapid mold opening stage; in response to the control parameters not conforming to expectations during execution, correcting the control parameters to obtain a reference deceleration distance corresponding to each speed of the rapid mold opening stage; obtaining the target speed of the current rapid mold opening stage; obtaining the reference deceleration distance corresponding to the target speed; and obtaining the advance deceleration distance based on the reference deceleration distance; and determining the end point of the rapid mold opening stage based on the advance deceleration distance.

[0010] In one possible implementation, the step of determining whether the control parameters meet expectations specifically includes: obtaining the target mold opening endpoint, and determining whether the control parameters meet expectations based on the historical deviation of the mold opening endpoint from the target mold opening endpoint.

[0011] In one possible implementation, the step of determining whether the control parameter meets expectations specifically includes: determining whether the control parameter was corrected in the previous mold opening operation; if the control parameter was corrected in the previous mold opening operation, determining whether the deviation between the target mold opening endpoint and the historical mold opening endpoint is not greater than a threshold deviation; if it is greater than the threshold deviation, the control parameter does not meet expectations; if it is not greater than the threshold deviation, determining whether the number of times the deviation between the target mold opening endpoint and the historical mold opening endpoint is not greater than the threshold deviation is less than a first threshold; if it is less than the first threshold, the control parameter does not meet expectations; if it is not less than the first threshold, the control parameter meets expectations; if the control parameter was not corrected in the previous mold opening operation, determining whether the deviation between the target mold opening endpoint and the historical mold opening endpoint is not greater than the threshold deviation; if it is not greater than the threshold deviation, the control parameter meets expectations; if it is greater than the threshold deviation, determining whether the number of times the deviation between the target mold opening endpoint and the historical mold opening endpoint is greater than the threshold deviation is less than a second threshold; if it is less than the second threshold, the control parameter meets expectations; if it is not less than the second threshold, the control parameter does not meet expectations.

[0012] In one possible implementation, the step of modifying the control parameters specifically includes: determining whether the mold opening endpoint exceeds the target mold opening endpoint; if the mold opening endpoint exceeds the target mold opening endpoint, increasing the advance deceleration distance in the control parameters; if the mold opening endpoint does not exceed the target mold opening endpoint, decreasing the advance deceleration distance in the control parameters.

[0013] In one possible implementation, the increase in the advance deceleration distance is determined based on how much the mold opening endpoint exceeds the target mold opening endpoint; wherein, the greater the difference between the mold opening endpoint and the target mold opening endpoint, the greater the increase in the advance deceleration distance; and the decrease in the advance deceleration distance is determined based on the distance between the mold opening endpoint and the target mold opening endpoint; wherein, the greater the distance between the mold opening endpoint and the target mold opening endpoint, the greater the decrease in the advance deceleration distance.

[0014] This application also provides a controller applied to an injection molding machine including a drive structure, a moving template, and a stationary template. The controller controls the drive structure to drive the moving template using the control method described above. The controller includes: an acquisition module for acquiring control parameters characterizing the position and velocity relationship of the moving template; the acquisition module is also used to acquire historical mold opening endpoints; a control module for controlling the movement of the moving template based on the control parameters; a judgment module for judging whether the control parameters meet expectations based on the historical mold opening endpoints; and a correction module for correcting the control parameters.

[0015] This application also provides a controller, including a processor and a memory interconnected; wherein the memory stores program instructions, and the processor retrieves the program instructions from the memory to execute the control method described above.

[0016] This application also provides an injection molding machine, which includes a controller, a drive structure, a moving platen, and a stationary platen. The controller is connected to the drive structure and is used to control the drive structure to drive the moving platen to move relative to the stationary platen to perform mold closing and mold opening actions. The controller is the controller described above.

[0017] This application provides a control method, controller, and injection molding machine for mold opening and closing. The control method includes: acquiring control parameters characterizing the position and speed relationship of a moving mold platen, and starting the moving mold platen based on the control parameters; responding to the moving mold platen executing an opening action, acquiring historical mold opening endpoints, and determining whether the control parameters meet expectations based on the historical mold opening endpoints; if the control parameters do not meet expectations, correcting the control parameters, and controlling the mold opening action based on the corrected control parameters. This continuous correction of control parameters based on actual mold opening actions, followed by execution of the mold opening action based on the corrected control parameters, improves the accuracy of each mold opening action, reduces mold opening deviation, and reduces the likelihood of over-stroke or incomplete mold opening during injection molding machine mold opening and closing. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein: Figure 1 This is a flowchart illustrating one embodiment of the injection molding machine mold opening and closing control method provided in this application; Figure 2 The mold closing action output curve is based on the mold opening and closing control method of the injection molding machine in this application, which controls the mold closing action. Figure 3 The mold opening action output curve is based on the mold opening and closing control method of the injection molding machine in this application. Figure 4 This is a flowchart illustrating one implementation method of obtaining control parameters for characterizing the position and velocity relationship of the moving template in this application; Figure 5 This is a flowchart illustrating the first implementation method of determining whether the control parameters meet expectations in this application; Figure 6 This is a flowchart illustrating the first implementation method of modifying the control parameters in this application; Figure 7 This is a schematic diagram of the structure of the first embodiment of the controller provided in this application; Figure 8 This is a schematic diagram of the second embodiment of the controller provided in this application. Detailed Implementation

[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It is understood that the specific embodiments described herein are only for explaining this application and not for limiting it. Furthermore, it should be noted that, for ease of description, only the parts related to this application are shown in the accompanying drawings, not all structures. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0020] The terms "first," "second," etc., used in this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or apparatuses.

[0021] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0022] In related technologies, the problem with injection molding machines is that when the injection molding machine performs the mold opening action, the moving platen is prone to overshoot, especially after long-term use of the injection molding machine or after the user adjusts the working parameters of the injection molding machine, the overshoot problem of the moving platen is more common.

[0023] To address the aforementioned problems, this application provides a control method, controller, and injection molding machine for mold opening and closing. Before the injection molding machine executes the mold opening action, the control method determines whether to correct the control parameters based on historical mold opening actions, and then executes the mold opening action based on the latest control parameters. This reduces the deviation between the actual mold opening endpoint and the target mold opening endpoint of the moving mold plate, thereby improving mold opening accuracy.

[0024] The following describes in detail, with reference to the accompanying drawings and embodiments, a control method for opening and closing the mold of an injection molding machine, a controller, and an injection molding machine provided in this application.

[0025] See Figure 1 , Figure 1 This is a flowchart illustrating one embodiment of the injection molding machine mold opening and closing control method provided in this application.

[0026] This application also provides an injection molding machine, which includes a controller, a drive structure, a moving platen, and a stationary platen. The controller is connected to the drive structure and is used to control the drive structure to drive the moving platen to move relative to the stationary platen to perform mold closing and mold opening actions. The injection molding machine controls the mold closing and mold opening actions using the control method described in any embodiment of this application. In this embodiment, the controller is the executing entity of the mold opening and closing control method. In one specific embodiment, the control method includes: S11: Obtain control parameters to characterize the relationship between the position and velocity of the moving template, and start the moving template based on the control parameters.

[0027] Control parameters are used by the controller to control the movement of the moving template, so that the moving template moves at a specified speed when it reaches a designated position. In this embodiment, the moving template is driven hydraulically, and the speed of the moving template is positively correlated with the percentage of hydraulic flow supplied. For example, in some embodiments, the control parameters for the mold closing action include: a speed of 0 when the moving platen is at a position of 400 mm; a speed of 60% flow rate when the moving platen is between 375 mm and 25 mm; a speed of 30% flow rate when the moving platen is between 15 mm and 5 mm; and a speed of 50% flow rate when the moving platen is between 3 mm and 2 mm. When controlling the mold closing action using these control parameters, the moving platen is continuously accelerated when it is between 400 mm and 375 mm. At a position between 375 mm and 25 mm, the moving platen closes rapidly at a speed of 60% flow rate. At a position between 15 mm and 5 mm, the moving platen slowly approaches the stationary platen at a speed of 30% flow rate to retain the film. At a position between 3 mm and 2 mm, the moving platen locks the mold at a speed of 50% flow rate. At a position between 2 mm and 0 mm, the moving platen continuously decelerates to 0 and closes with the stationary platen.

[0028] In some embodiments, the control parameters for the mold opening action include: the starting position of the moving platen is 0 mm, the starting position speed is 0, and the moving platen speed increases between 0 mm and 10 mm. The moving platen speed is 25% of the flow rate when its position is between 10 mm and 15 mm, and 55% of the flow rate when its position is between 20 mm and 390 mm. When controlling the mold opening action using the above control parameters, the moving platen is controlled to open the mold at 25% of the flow rate between 10 mm and 15 mm; between 20 mm and 390 mm, the moving platen is controlled to open the mold rapidly at 55% of the flow rate; after 390 mm, the moving platen is controlled to continuously decelerate until it stops and reaches the mold opening endpoint.

[0029] S12: In response to the moving template executing the mold opening action, obtain the historical mold opening endpoint, and determine whether the control parameters meet the expectations based on the historical mold opening endpoint.

[0030] During the mold opening process, the moving mold plate begins to decelerate at the end point of the rapid mold opening phase. When the speed of the moving mold plate decreases to 0, the moving mold plate reaches the mold opening endpoint. The position of the end point of the rapid mold opening phase affects the final mold opening endpoint. For example, if the end point of the rapid mold opening phase is too early, the deceleration distance will be too large, resulting in the mold opening endpoint not reaching the target mold opening endpoint. If the end point of the rapid mold opening phase is too late, the deceleration distance will be too small, resulting in the mold opening endpoint exceeding the target mold opening endpoint.

[0031] In this context, the historical mold opening endpoint refers to the mold opening endpoint of the previous mold opening action. In some embodiments, the step of determining whether the control parameters meet expectations specifically includes: obtaining the target mold opening endpoint, and determining whether the control parameters meet expectations based on the magnitude of the deviation between the historical mold opening endpoint and the target mold opening endpoint. For example, if the deviation between the historical mold opening endpoint and the target mold opening endpoint reaches a threshold deviation, then the control parameters do not meet expectations. In other embodiments, when the historical mold opening endpoint exceeds the target mold opening endpoint, the control parameters do not meet expectations, in order to reduce the problem of mold damage caused by over-expansion.

[0032] If the control parameters do not meet expectations, execute S13; if the control parameters meet expectations, execute S14.

[0033] S13: Correct the control parameters and control the mold opening action based on the corrected control parameters.

[0034] When control parameters do not meet expectations, historical control parameters will cause the mold opening action to deviate from the target mold opening endpoint by a threshold. By correcting the control parameters, the mold opening action can be controlled based on the corrected control parameters to bring the mold opening endpoint closer to the target mold opening endpoint. For example, if the historical mold opening endpoint exceeds the target mold opening endpoint, the control parameters can be corrected to advance the termination point of the rapid mold opening stage, allowing the moving mold plate to decelerate earlier. If the historical mold opening endpoint does not reach the target mold opening endpoint, the control parameters can be corrected to delay the termination point of the rapid mold opening stage, allowing the moving mold plate to decelerate later.

[0035] S14: Control the mold opening action based on historical control parameters.

[0036] The above control method can continuously correct the control parameters based on the actual mold opening action, and then execute the mold opening action based on the corrected control parameters. This can improve the mold opening accuracy of each mold opening action, reduce mold opening deviation, and make it less likely for the injection molding machine to have problems such as over-stroke or incomplete mold opening during mold opening and closing.

[0037] Please refer to the following: Figure 2 and Figure 3 , Figure 2 The mold closing action output curve is based on the mold opening and closing control method of the injection molding machine in this application, which controls the mold closing action. Figure 3 The output curve of the mold opening action is based on the mold opening and closing control method of the injection molding machine in this application.

[0038] In some embodiments, the mold closing action includes a rapid mold closing stage, a mold holding stage, and a mold locking stage. For example... Figure 2 As shown, Figure 2Section BC is the rapid mold closing stage. In this stage, the moving mold platen approaches the stationary mold platen at a relatively high speed. In this embodiment, the moving mold platen operates at 60% of its flow rate during the rapid mold closing stage. Section DE is the mold protection stage. In this stage, the moving mold platen approaches the stationary mold platen. The moving mold platen is controlled to move at a lower speed and pressure to reduce the risk of mold damage caused by foreign objects in the mold cavity. In this embodiment, the moving mold platen operates at 30% of its flow rate during the mold protection stage. Section FG is the mold locking stage. In this stage, a high pressure is applied to the moving mold platen to slowly lock it to the stationary mold platen, gradually sealing the cavity. In this embodiment, the moving mold platen operates at 50% of its flow rate during the mold locking stage.

[0039] In some embodiments, the control parameters also include the pressure on the moving template during the mold holding and locking phases. Specifically, in Figure 2 In the illustrated mold closing action, the pressure applied during the DE mold holding stage is 30 bar, and the pressure applied during the FG mold locking stage is 175 bar.

[0040] In some embodiments, the mold opening action includes a breaking stage and a rapid mold opening stage. For example... Figure 3 As shown, Figure 3 The IJ segment is the mold-breaking stage. During this stage, the moving mold platen is controlled at a relatively low speed and pressure to open the mold a short distance, releasing the stress generated by the stretching of the tie rod. In this embodiment, the speed of the moving mold platen during the mold-breaking stage is 25% of the flow rate. The KL segment is the rapid mold-opening stage. During this stage, the moving mold platen is controlled to move at a higher speed, enabling rapid separation of the moving mold platen from the stationary mold platen. In this embodiment, the speed during the rapid mold-opening stage is 55% of the flow rate.

[0041] In some embodiments, the step of obtaining control parameters characterizing the position-velocity relationship of the moving mold plate specifically includes: obtaining control parameters for the target position and target velocity of each stage, including the start and end points of the rapid mold closing stage, mold holding stage, mold locking stage, mold breaking stage, and rapid mold opening stage. For example, combined with Figure 2 and Figure 3 As shown, the control parameters include Figure 2 The position and velocity at point B (60% flow rate at position 375 mm), the position and velocity at points C, D, E, F, and G. Control parameters also include... Figure 3 The position and velocity of point I, point J, point K, and point L are all controlled. By using control parameters including the aforementioned target position and target velocity, the moving template can be controlled to move to the target position with the target velocity, enabling accurate control of the moving template during mold closing and opening actions.

[0042] In some embodiments, the mold closing and mold opening actions further include a speed transition section connecting the various stages. The speed change rate in the middle portion of the speed transition section is greater than the speed change rate at the beginning and end portions. The control parameters also include the speed change rate of each portion within the speed transition section. For example, ... Figure 2 As shown, in this embodiment, AB is the acceleration speed transition segment, during which the moving mold plate accelerates to the target speed of the rapid mold closing stage. CD is the deceleration speed transition segment, connecting the rapid mold closing stage and the mold holding stage, during which the moving mold plate decelerates to the target speed of the mold holding stage. EF is the acceleration speed transition segment, and GH is the deceleration speed transition segment. Figure 3 As shown, segment HI is the speed transition segment for acceleration, segment JH is the speed transition segment for deceleration, and segment LM is the speed transition segment for acceleration. Figure 2 and Figure 3 As shown, in this embodiment, the lines of each speed transition segment are lines with continuously changing slopes. That is, the rate of speed change varies in different regions of each speed transition segment, and the rate of speed change in the middle section is greater than that at the beginning and end. This setting allows for initial acceleration / deceleration changes with a smaller acceleration, followed by a larger acceleration / deceleration, and then, as the moving template approaches the target speed, a smaller acceleration / deceleration is applied. This results in smoother acceleration / deceleration initiation and stopping during speed changes, reducing the likelihood of sudden impact forces and contributing to the stability of the moving template's motion. In this embodiment, the control parameters include the rate of speed change in each region of each speed transition segment. Controlling the acceleration / deceleration of the moving template using these parameters helps maintain the stability of its motion.

[0043] In some embodiments, the rate of change of speed in the control speed transition section changes continuously, and the rate of change of speed at the beginning and end portions is 0. For example... Figure 2 and Figure 3 As shown in the figure, in this embodiment, each speed transition segment is a smooth curve with a slope of 0 at the beginning and end, meaning the change in the rate of speed change is continuous and smooth, and the acceleration at the beginning and end is 0. This setting makes the acceleration and deceleration of the moving template smoother, further reducing the possibility of sudden impact forces and making the moving template less prone to positional deviations in mold opening and closing due to sudden impact forces. For example, Figure 2 and Figure 3As shown in the figure, in this embodiment, each speed transition segment adopts sin slope control, and the speed transition segment is similar to a sin curve in the figure. As mentioned above, the speed transition segment of this application adopts sin slope control, and the speed change rate changes continuously, allowing the acceleration and deceleration of the moving mold plate to smoothly and directly transition to the target speed in one step. Therefore, it can reduce the intermediate stages of speed change in the mold opening and closing actions, thereby reducing the number of different stages in the mold opening and closing actions. This means that only a smaller number of control parameters are needed for the target positions of the stage start and end points and the target speeds at those positions. Fewer control parameters reduce the probability of deviations between the mold closing and opening actions, achieving better control performance. Furthermore, when the mold is changed or the mold opening endpoint needs adjustment, the user only needs to set and adjust a small number of control parameters. The control method of this application can automatically update and adjust the start and end points of each stage by repeatedly executing the step of correcting the control parameters, automatically adapting to the optimal control parameters, so that the injection molding machine's mold opening can reach the set target mold opening endpoint.

[0044] Please refer to the following: Figure 4 , Figure 4 This is a flowchart illustrating one embodiment of the step in obtaining control parameters characterizing the position and velocity relationship of the moving template. In some embodiments, the control parameters include an advance deceleration distance, which is the distance between the end point of the rapid mold opening stage and the target mold opening endpoint. The step of obtaining control parameters characterizing the position and velocity relationship of the moving template further includes: S111: Pre-control the injection molding machine to repeatedly execute the mold opening action at different speeds during the rapid mold opening phase. In response to the control parameters not meeting expectations during execution, the control parameters are corrected to obtain the reference deceleration distance corresponding to each speed of the rapid mold opening phase.

[0045] This step is used to preset the reference deceleration distance for the rapid mold opening stage of the injection molding machine at different speeds before it leaves the factory.

[0046] For example, the injection molding machine can be pre-controlled to repeatedly execute the mold opening action at 10 different flow rate speeds: 10% flow rate, 20% flow rate, 30% flow rate, 40% flow rate, 50% flow rate, 60% flow rate, 70% flow rate, 80% flow rate, 90% flow rate, and 100% flow rate. By repeatedly executing the mold opening action at each speed and adjusting the control parameters for each speed, the reference deceleration distance for each of the 10 different flow rate speeds can be obtained.

[0047] In some embodiments, when performing the first mold opening action in each group of rapid mold opening stages at different speeds, a larger advance deceleration distance is used for the first mold opening. This reduces the problem of overshooting during the determination of the reference deceleration distance. The larger advance deceleration distance for the first mold opening, combined with repeated mold opening adjustments to the control parameters, allows for a reduction in the advance deceleration distance to obtain the reference deceleration distance.

[0048] S112: Obtain the target speed of the current rapid mold opening stage, obtain the reference deceleration distance that matches the target speed, and obtain the advance deceleration distance based on the reference deceleration distance.

[0049] This step is used to obtain a suitable and conservative deceleration distance from the reference deceleration distance based on the speed of the current rapid mold opening stage set by the injection molding machine. For example, if the current speed of the rapid mold opening stage is set to 75% of the flow rate, then the reference deceleration distance corresponding to the speed of 80% of the flow rate in S111 is selected as the initial advance deceleration distance, and the mold opening action is performed with this initial advance deceleration distance to continuously correct the new advance deceleration distance so that the mold opening end point will not overshoot.

[0050] S113: Determine the termination point of the rapid mold opening stage based on the advance deceleration distance.

[0051] For example, please continue reading Figure 3 If the calculated advance deceleration distance is 10 mm, then the termination point of the rapid mold opening stage is the target mold opening endpoint minus the advance deceleration distance, specifically the position of point M in the figure minus the advance deceleration distance. The calculated termination point of the rapid mold opening stage is 390 mm.

[0052] When performing the mold opening action again in a subsequent operation, the advance deceleration distance is adjusted based on the deviation between the actual mold opening endpoint and the target mold opening endpoint, so as to gradually obtain the optimal advance deceleration distance under the current operating conditions.

[0053] Please see Figure 5 , Figure 5 This is a flowchart illustrating an embodiment of step one of the present application's methods for determining whether control parameters meet expectations. In some embodiments, the step of determining whether control parameters meet expectations specifically includes: S121: Determine if there were any correction control parameters in the previous mold opening action.

[0054] If yes, then execute S122; otherwise, execute S123.

[0055] S122: Determine whether the deviation between the target mold opening endpoint and the historical mold opening endpoint is not greater than the threshold deviation.

[0056] If yes, then execute S124; otherwise, execute S125.

[0057] Specifically, the threshold deviation can be a reasonable value such as 1 mm or 2 mm.

[0058] S124: Determine whether the number of times the deviation between the target mold opening endpoint and the historical mold opening endpoint is not greater than a threshold is less than the first threshold.

[0059] If yes, then execute S127; otherwise, execute S126.

[0060] In this embodiment, the first threshold can be a reasonable value such as 2, 3, or 4.

[0061] S126: Control parameters meet expectations.

[0062] S127: Control parameters do not meet expectations.

[0063] S125: Control parameters do not meet expectations.

[0064] S123: Determine whether the deviation between the target mold opening endpoint and the historical mold opening endpoint is not greater than the threshold deviation.

[0065] If yes, then execute S1231; otherwise, execute S1232.

[0066] S1231: Control parameters meet expectations.

[0067] S1232: Determine whether the number of times the deviation between the target mold opening endpoint and the historical mold opening endpoint is greater than a threshold is less than a second threshold.

[0068] If yes, then execute S1233; otherwise, execute S1234.

[0069] The second threshold can be a reasonable value such as 2, 3, or 4. The value of the second threshold can be the same as or different from the first threshold.

[0070] S1233: Control parameters meet expectations.

[0071] S1234: Control parameters do not meet expectations.

[0072] Please see Figure 6 , Figure 6 This is a flowchart illustrating one embodiment of the step of modifying the control parameters in this application. In some embodiments, the step of modifying the control parameters specifically includes: S131: Determine whether the mold opening endpoint exceeds the target mold opening endpoint.

[0073] If yes, then execute S132; otherwise, execute S133.

[0074] S132: Increase the advance deceleration distance in the control parameters.

[0075] This step is performed when the actual mold opening endpoint exceeds the target mold opening endpoint. Specifically, when the mold opening endpoint exceeds the target mold opening endpoint, it means that the moving mold plate started decelerating too late from the rapid mold opening stage. When the moving mold plate reaches the target mold opening endpoint, it has not yet decelerated to a stop. By increasing the advance deceleration distance, the termination point of the rapid mold opening stage can be brought forward, allowing the moving mold plate to decelerate earlier, thus enabling it to decelerate to a stop when it reaches the target mold opening endpoint.

[0076] In some embodiments, the increment value of the advance deceleration distance is determined based on how much the mold opening endpoint exceeds the target mold opening endpoint; wherein, the greater the mold opening endpoint exceeds the target mold opening endpoint, the larger the increment value of the advance deceleration distance. In some embodiments, the increment value of the advance deceleration distance can be (P1-P0)*K2; wherein, P1 is the actual mold opening endpoint, P0 is the target mold opening endpoint, and K2 is an adjustment coefficient.

[0077] S133: Reduce the advance deceleration distance in the control parameters.

[0078] This step is performed if the actual mold opening endpoint does not exceed the target mold opening endpoint. Specifically, if the mold opening endpoint does not exceed the target mold opening endpoint, it means that the moving mold plate started decelerating too early from the rapid mold opening stage. Before the moving mold plate reaches the target mold opening endpoint, the termination point of the rapid mold opening stage can be delayed by reducing the early deceleration distance, allowing the moving mold plate to decelerate later, so that the moving mold plate can reach the target mold opening endpoint when it decelerates to a stop.

[0079] In some embodiments, the reduction magnitude of the advance deceleration distance is determined based on the distance between the mold opening endpoint and the target mold opening endpoint; wherein, the greater the distance between the mold opening endpoint and the target mold opening endpoint, the greater the reduction magnitude of the advance deceleration distance. In some embodiments, the reduction magnitude of the advance deceleration distance can be (P0-P1)*K2; wherein, P1 is the actual mold opening endpoint, P0 is the target mold opening endpoint, and K2 is an adjustment coefficient.

[0080] As described above, the actual deceleration distance is adjusted based on the historical mold opening endpoint and the target mold opening endpoint. The greater the distance between the mold opening endpoint and the target mold opening endpoint, the greater the increase in the controlled advance deceleration distance. Conversely, the greater the distance between the mold opening endpoint and the target mold opening endpoint, the greater the decrease in the controlled advance deceleration distance. By correcting the control parameters through this correction logic before each mold opening action, the accuracy of each mold opening action can be improved, mold opening deviations can be reduced, and problems such as over-stroke and incomplete mold opening are less likely to occur during the mold opening and closing of the injection molding machine.

[0081] Please see Figure 7 , Figure 7This is a schematic diagram of the first embodiment of the controller provided in this application. In some embodiments, the controller 1000 is applied to an injection molding machine including a drive structure, a moving template, and a stationary template. The controller 1000 controls the drive structure to drive the moving template through the control method of any of the above embodiments. The controller 1000 includes an acquisition module 2000, a control module 4000, a judgment module 3000, and a correction module 5000. The acquisition module 2000 is used to acquire control parameters characterizing the position and speed relationship of the moving template; the acquisition module 2000 is also used to acquire historical mold opening endpoints; the control module 4000 is used to control the movement of the moving template based on the control parameters; the judgment module 3000 is used to judge whether the control parameters meet expectations based on historical mold opening endpoints; and the correction module 5000 is used to correct the control parameters.

[0082] Please see Figure 8 , Figure 8 This is a schematic diagram of the second embodiment of the controller provided in this application. The controller 100 includes a processor 200 and a memory 300 connected to each other. The memory 300 stores program instructions, and the processor 200 retrieves the program instructions from the memory 300 to execute the control method as described in any of the above embodiments.

[0083] Correspondingly, this application also provides an injection molding machine, which includes a controller, a drive structure, a moving platen, and a stationary platen. The controller is connected to the drive structure and is used to control the drive structure to drive the moving platen to move relative to the stationary platen to perform mold closing and mold opening actions. The controller is a controller 1000 or a controller 100.

[0084] In the several embodiments provided in this application, it should be understood that the disclosed methods, devices, and apparatuses can be implemented in other ways. For example, the device and apparatus embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection of devices or units may be electrical, mechanical, or other forms.

[0085] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0086] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0087] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) or processor to execute all or part of the steps of the methods of various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

Claims

1. A method for controlling the opening and closing of an injection molding machine, characterized in that, The injection molding machine includes a moving platen and a stationary platen. The moving platen, when driven, can move relative to the stationary platen to perform a mold closing or opening action. The control method includes: Obtain control parameters that characterize the position and velocity relationship of the moving template, and start the moving template based on the control parameters; In response to the moving template performing the mold opening action, the historical mold opening endpoint is obtained, and based on the historical mold opening endpoint, it is determined whether the control parameters meet the expectations; If the control parameters do not meet expectations, the control parameters are corrected, and the mold opening action is controlled based on the corrected control parameters.

2. The control method according to claim 1, characterized in that, The mold closing action includes a rapid mold closing stage, a mold holding stage, and a mold locking stage; the mold opening action includes a mold breaking stage and a rapid mold opening stage; the step of obtaining control parameters characterizing the position and speed relationship of the moving mold plate specifically includes: Obtain control parameters including the target position and target velocity at the start and end points of each of the above stages.

3. The control method according to claim 2, characterized in that, The mold closing action and the mold opening action also include a speed transition section connecting each stage, wherein the speed change rate of the middle part of the speed transition section is greater than the speed change rate of the beginning and end parts; wherein, the control parameters also include the speed change rate of each part in the speed transition section.

4. The control method according to claim 3, characterized in that, The rate of change of speed in the speed transition section is controlled to change continuously, and the rate of change of speed in the start and end portions is 0.

5. The control method according to claim 2, characterized in that, The control parameters include an advance deceleration distance, which is the distance between the end point of the rapid mold opening stage and the target mold opening endpoint. The step of obtaining control parameters for characterizing the position-velocity relationship of the moving template further includes: The injection molding machine is pre-controlled to repeatedly execute the mold opening action at different speeds during the rapid mold opening phase. In response to the control parameters not meeting expectations during execution, the control parameters are corrected to obtain a reference deceleration distance corresponding to each of the rapid mold opening phases at each speed. Obtain the target speed of the current rapid mold opening stage, obtain the reference deceleration distance that matches the target speed, and obtain the advance deceleration distance based on the reference deceleration distance; The termination point of the rapid mold opening stage is determined based on the aforementioned advance deceleration distance.

6. The control method according to claim 1, characterized in that, The step of determining whether the control parameters meet expectations specifically includes: Obtain the target mold opening endpoint, and determine whether the control parameters meet expectations based on the deviation of the historical mold opening endpoint from the target mold opening endpoint.

7. The control method according to claim 6, characterized in that, The step of determining whether the control parameters meet expectations specifically includes: Determine whether the control parameters were corrected during the previous mold opening operation; If the control parameters were corrected in the previous mold opening operation, determine whether the deviation between the target mold opening endpoint and the historical mold opening endpoint is not greater than a threshold deviation; if it is greater than the threshold deviation, the control parameters do not meet expectations; if it is not greater than the threshold deviation, determine whether the number of times the deviation between the target mold opening endpoint and the historical mold opening endpoint is not greater than the threshold deviation is less than a first threshold; if it is less than the first threshold, the control parameters do not meet expectations; if it is not less than the first threshold, the control parameters meet expectations. If the control parameters were not corrected in the previous mold opening operation, determine whether the deviation between the target mold opening endpoint and the historical mold opening endpoint is not greater than the threshold deviation; if it is not greater than the threshold deviation, the control parameters meet expectations; if it is greater than the threshold deviation, determine whether the number of times the deviation between the target mold opening endpoint and the historical mold opening endpoint is greater than the threshold deviation is less than a second threshold; if it is less than the second threshold, the control parameters meet expectations; if it is not less than the second threshold, the control parameters do not meet expectations.

8. The control method according to claim 5, characterized in that, The step of correcting the control parameters specifically includes: Determine whether the mold opening endpoint exceeds the target mold opening endpoint. If the mold opening endpoint exceeds the target mold opening endpoint, increase the advance deceleration distance in the control parameters. If the mold opening endpoint does not exceed the target mold opening endpoint, reduce the advance deceleration distance in the control parameters.

9. The control method according to claim 8, characterized in that, The increase in the advance deceleration distance is determined based on how much the mold opening endpoint exceeds the target mold opening endpoint; wherein, the greater the increase in the advance deceleration distance, the more the mold opening endpoint exceeds the target mold opening endpoint. The reduction magnitude of the advance deceleration distance is determined based on the distance between the mold opening endpoint and the target mold opening endpoint; wherein, the greater the distance between the mold opening endpoint and the target mold opening endpoint, the greater the reduction magnitude of the advance deceleration distance.

10. A controller, characterized in that, An injection molding machine comprising a drive structure, a moving platen, and a stationary platen, wherein the controller controls the drive structure to drive the moving platen using the control method of any one of claims 1-9, and the controller comprises: The acquisition module is used to acquire control parameters that characterize the position and velocity relationship of the moving template; the acquisition module is also used to acquire historical mold opening endpoints; The control module is used to control the movement of the moving template based on the control parameters; The judgment module is used to determine whether the control parameters meet expectations based on the historical mold opening endpoint; A correction module is used to correct the control parameters.

11. A controller, characterized in that, It includes interconnected processors and memory; wherein the memory stores program instructions, and the processor retrieves the program instructions from the memory to execute the control method as described in any one of claims 1-9.

12. An injection molding machine, characterized in that, The injection molding machine includes a controller, a drive structure, a moving platen, and a stationary platen. The controller is connected to the drive structure and is used to control the drive structure to drive the moving platen to move relative to the stationary platen to perform mold closing and mold opening actions. The controller is the controller described in claim 10 or 11.

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