A hinge mold opening synchronous control method of an openable rim mold

Abstract

The present application relates to a kind of hinge mold opening synchronous control method of openable wheel rim mold, comprising: in response to mold opening instruction, the mold opening state parameters of multiple hinge segments are obtained, the mold opening state parameters include mold opening displacement parameter, mold opening response parameter and mold opening load parameter, whether the mold opening state parameters of each hinge segment meet the condition of synchronous mold opening is judged, after meeting the condition, enter synchronous mold opening control process;In synchronous mold opening control process, according to the mold opening displacement difference and mold opening load difference between each hinge segment, determine the constrained segment, and take the constrained segment as the synchronous control reference, to the hinge segment that mold opening is ahead of schedule, limit speed control or pause control is executed;When the constrained segment meets the synchronous recovery condition, the constrained segment is determined again and synchronous mold opening control is continued, until each hinge segment reaches the preset mold opening completion position, to limit the expansion of mold opening displacement difference, improve the mold opening of wheel rim mold.

Description

Technical Field

[0001] This invention relates to the field of synchronous control technology for opening wheel rim molds, specifically a method for synchronous control of hinge opening of an openable wheel rim mold. Background Technology

[0002] In existing technologies, wheel rim or hub forming molds, to meet the requirements of lightweight, deep grooves, and complex wheel wells, typically design the forming area as a structure with side molds, core molds, top molds, or multiple movable mold segments working together. Demolding is accomplished through actions such as ejection, core pulling, and side mold opening. Publication number CN115383082A discloses a mold core pulling and ejection structure suitable for deep groove type wheel hubs. Through the cooperation of an ejector plate, gears, guide tooth plates, and ejector blocks, the grooved area can be partially cast according to the mold shape and retract or extend in conjunction with the ejection action, thereby reducing the costs of aluminum smelting, recycling, and machining, and meeting the requirements for differentiated and lightweight wheel hub designs. This type of solution illustrates that as the complexity of wheel rim and hub shapes increases, the number of movable parts in the mold and their interrelationships increase. The demolding process is no longer a simple separation action of the upper and lower molds, but involves multiple mold segments, core pulling mechanisms, or ejection mechanisms moving collaboratively in a predetermined sequence.

[0003] On the other hand, CN118456798A discloses a mold core-pulling acceleration device and method. Addressing the problems of long drive strokes, large mold space occupation, long extraction time, and high manufacturing costs associated with core-pulling structures with long undercuts, it employs a linearly movable and rotatable drive gear in conjunction with a core-pulling rack and a fixed rack. This allows the core-pulling slider to achieve accelerated movement based on the drive actuator stroke, thereby reducing the drive mechanism stroke and the overall mold size. This type of technology focuses on improving the motion efficiency of a single core-pulling component or slider through mechanical transmission. However, for situations where multiple hinged mold segments in an openable rim mold open simultaneously, relying solely on mechanical structures or unified mold-opening commands makes it difficult to reflect in real-time the displacement differences, response differences, and load differences of each hinged mold segment during the mold-opening process.

[0004] Especially during the mold opening process of wheel rim molds, the different hinge mold segments may exhibit inconsistent responses due to factors such as mold sticking, localized clamping, guide friction, differences in casting shrinkage, or differences in driving resistance. If some mold segments have already opened ahead of schedule, while another mold segment is in a constrained or lagging state, continuing to open the mold at a uniform speed can easily lead to an increase in the displacement difference between the mold segments, causing localized tension on the casting, uneven stress on the parting surface, and uneven load on the hinge mechanism. In severe cases, it may even cause mold jamming, damage to the wheel rim blank, or interruption of the mold opening action. Although existing publicly available solutions can improve the efficiency of local forming, ejection, or core pulling of the wheel hub, they lack a control method based on mold opening displacement parameters, mold opening response parameters, and mold opening load parameters to simultaneously determine multiple hinge mold segments, identify constrained mold segments, limit or pause the speed of the leading mold segment, and verify synchronous recovery. Therefore, it is still necessary to propose a synchronous control scheme that can dynamically limit the expansion of displacement difference and ensure coordinated opening of each mold segment throughout the entire mold opening process. Summary of the Invention

[0005] The purpose of this invention is to provide a hinge-based synchronous control method for opening a wheel rim mold, thereby solving some of the drawbacks and shortcomings pointed out in the background art.

[0006] The present invention adopts the following technical solution to solve the above-mentioned technical problems:

[0007] In response to the mold opening command, the mold opening state parameters of multiple hinge mold segments are obtained. The mold opening state parameters include mold opening displacement parameters, mold opening response parameters, and mold opening load parameters. Based on the mold opening state parameters of each hinge mold segment, it is determined whether each hinge mold segment meets the synchronous mold opening conditions. After each hinge mold segment meets the synchronous mold opening conditions, the synchronous mold opening control process is entered.

[0008] During the synchronous mold opening control process, based on the mold opening displacement difference and mold opening load difference between each hinge mold piece, a constrained mold piece is determined from multiple hinge mold pieces. The constrained mold piece is used as the synchronous control reference, and speed limiting control or pause control is performed on the hinge mold pieces that are ahead of the mold opening relative to the constrained mold piece, so as to limit the expansion of the mold opening displacement difference between each hinge mold piece.

[0009] Once the constrained mold segment meets the synchronous recovery condition, the constrained mold segment is redefined and the synchronous mold opening control process continues until each hinge mold segment reaches the preset mold opening completion position.

[0010] Furthermore, the method for determining the constrained module is as follows: when a hinge module lags behind the other hinge modules in terms of mold opening displacement, and the mold opening load parameter of the hinge module increases compared to the mold opening load parameter before the mold opening command is issued, the hinge module is designated as a candidate constrained module; after the control system performs pre-speed limiting control or pre-pause control on the hinge module that is ahead of the candidate constrained module in mold opening, it issues a trial release command to the candidate constrained module; if the mold opening increment of the candidate constrained module within a preset response time is less than a preset response threshold, and the mold opening load parameter is not lower than the mold opening load parameter before the trial release command is issued, then the candidate constrained module is determined as a constrained module.

[0011] Furthermore, the speed limiting control or pause control is as follows: a leading allowable boundary is set according to the current mold opening displacement parameter, current mold opening response parameter and current mold opening load parameter of the constrained mold segment; when any hinge mold segment reaches the leading allowable boundary, the hinge mold segment is switched to a waiting follow state; the hinge mold segment in the waiting follow state continues to open the mold after the constrained mold segment generates a new valid mold opening response.

[0012] Furthermore, the synchronization recovery condition is as follows: when the hinged module that is ahead of the constrained module in mold opening is under speed limiting control or pause control, the control system issues a recovery verification command to the constrained module; when the constrained module generates a mold opening response in the same direction, the mold opening load parameter of the constrained module has not increased relative to the mold opening load parameter before the recovery verification command was issued, and the mold opening displacement difference between each hinged module has not increased, it is determined that the constrained module meets the synchronization recovery condition.

[0013] Furthermore, the advance allowable boundary is dynamically adjusted according to the continuity of the mold opening response of the constrained mold segment; when the constrained mold segment does not generate a new effective mold opening response within a continuous control cycle, the advance allowable boundary is locked to the current mold opening displacement difference, and the hinge mold segment in the waiting follow state is prohibited from expanding the mold opening amount.

[0014] Furthermore, the control target of the hinged module in the waiting-to-follow state is switched from mold opening advancement to mold opening displacement difference maintenance; when the constrained module generates a new effective mold opening response, the hinged module in the waiting-to-follow state continues to open the mold according to a following increment that is less than or equal to the mold opening increment of the constrained module.

[0015] Furthermore, the new effective mold opening response is determined based on both the mold opening increment and the mold opening load parameter. When the constrained mold segment generates a mold opening increment, but the mold opening load parameter of the constrained mold segment increases synchronously relative to the previous control cycle, the control system determines that the constrained mold segment has not generated a new effective mold opening response and maintains the mold opening displacement difference of the hinged mold segment in the waiting follow state.

[0016] Furthermore, the recovery verification command is a mold opening command with an amplitude lower than the reference mold opening command amplitude in the synchronous mold opening control process and a duration less than a preset duration; when the constrained module generates a mold opening response under the action of the recovery verification command, but the mold opening load parameter of the constrained module increases relative to the mold opening load parameter before the recovery verification command is issued, the control system determines that the constrained module does not meet the synchronous recovery condition, and maintains the speed limiting control or pause control of other hinge modules.

[0017] Furthermore, the consistent mold opening response means that the constrained mold lobe produces a mold opening change in the same direction under the action of two consecutive recovery verification commands; when the difference between the two mold opening changes in the same direction is outside the preset difference range, or when the difference in mold opening displacement between each hinge mold lobe increases, the control system determines that the constrained mold lobe does not meet the synchronous recovery condition.

[0018] Furthermore, when the constrained module generates an opening response under the action of the recovery verification command, but the opening load parameter of the constrained module increases relative to the opening load parameter before the recovery verification command is issued, the control system reduces the amplitude of the next recovery verification command, and releases the speed limiting control or pause control of other hinge modules after the opening response amount of the constrained module reaches the preset response threshold and the opening load parameter is lower than the opening load parameter before the recovery verification command is issued.

[0019] This invention improves the accuracy of state identification and the reliability of control in the hinge mold opening process by first acquiring the mold opening displacement parameters, mold opening response parameters, and mold opening load parameters of multiple hinge mold segments after responding to the mold opening command, and then determining whether each hinge mold segment meets the synchronous mold opening conditions. This allows the synchronous mold opening control process to be based on the actual motion and stress state of each mold segment, rather than solely on a unified mold opening command.

[0020] In the synchronous mold opening control process, this invention determines the constrained mold segment based on the mold opening displacement difference and mold opening load difference between each hinge mold segment, and uses the constrained mold segment as the synchronous control benchmark. Speed ​​limiting control or pause control is performed on the hinge mold segments that open ahead of the constrained mold segment. This can effectively limit the expansion of the mold opening displacement difference between each hinge mold segment, reduce the risk of casting scratches, mold segment off-center loads, uneven hinge force, and mold jamming, and ensure that the rim mold can still open smoothly under complex resistance conditions.

[0021] After the constrained mold petals meet the synchronous recovery conditions, the present invention re-determines the constrained mold petals and continues to execute the synchronous mold opening control process until each hinge mold petal reaches the preset mold opening completion position. This allows the control benchmark to be dynamically updated according to the actual state of each mold petal, avoiding the long-term use of fixed mold petals or fixed speed as the control basis, which is beneficial to improving the continuity, synchronization and automation of the mold opening action. Attached Figure Description

[0022] Figure 1 This is a flowchart illustrating the hinge mold opening synchronization control method of the present invention.

[0023] Figure 2 This is a comparison diagram of the mold opening displacement and load of each hinge module in Embodiment 1 of the present invention.

[0024] Figure 3 This is a graph showing the relationship between mold opening displacement hysteresis and threshold in Embodiment 1 of the present invention.

[0025] Figure 4 This is the mold opening increment control diagram in the waiting follow state in Embodiment 1 of the present invention.

[0026] Figure 5 This is a diagram showing the limitation of the amplitude and duration of the recovery verification command in Embodiment 2 of the present invention.

[0027] Figure 6 This is a stability determination graph of two consecutive recovery verification responses in Embodiment 2 of the present invention.

[0028] Figure 7 This is a joint determination diagram of synchronization recovery conditions in Embodiment 2 of the present invention. Detailed Implementation

[0029] As attached Figure 1As shown, in one embodiment, after receiving the mold opening command from the rim mold, the control system first collects the mold opening state parameters of multiple hinge mold segments. The mold opening state parameters include mold opening displacement parameters, mold opening response parameters, and mold opening load parameters. The mold opening displacement parameters represent the degree of opening of the hinge mold segments relative to their initial closed position. The mold opening response parameters represent the timeliness and continuity of the displacement change of the hinge mold segments under the action of the mold opening command. The mold opening load parameters represent the driving resistance or equivalent load experienced by the hinge mold segments during the mold opening process. The mold opening displacement parameters can be obtained through displacement detection devices installed at the drive mechanism, hinge mold segments, or mold reference position. The mold opening response parameters can be obtained based on the presence, direction, and continuity of the mold opening displacement change within a continuous control cycle. The mold opening load parameters can be obtained through drive hydraulic pressure, drive current, thrust detection devices, or equivalent load detection modules. The control system determines whether each hinge mold segment meets the conditions for synchronous mold opening based on the mold opening status parameters of each hinge mold segment. When the difference in mold opening displacement, mold opening response, and mold opening load of each hinge mold segment is within the allowable range, the control system enters the synchronous mold opening control process. The allowable range can be pre-stored in the control system and determined based on the specifications of the rim mold, the number of hinge mold segments, the stroke of the drive mechanism, and the mold opening debugging results.

[0030] During synchronous mold opening control, the control system continuously compares the mold opening displacement difference and mold opening load difference between each hinge mold segment. When a hinge mold segment lags behind other hinge mold segments in mold opening and its mold opening load increases relatively, the control system identifies this hinge mold segment as a constrained mold segment. Subsequently, the control system uses the mold opening state of the constrained mold segment as the synchronous control benchmark, and performs speed limiting control or pause control on hinge mold segments that are ahead of the constrained mold segment in mold opening, so that the ahead hinge mold segments no longer continue to increase the mold opening displacement difference with the constrained mold segments. Speed ​​limiting control can reduce the mold opening speed command of the corresponding hinge mold segment drive mechanism or reduce the drive output, while pause control can stop the corresponding hinge mold segment drive mechanism from continuing to open the mold and maintain its current position or current allowable displacement range. Through the above control methods, uneven mold force caused by some hinge mold segments opening too quickly can be avoided, and the risk of jamming or uneven load caused by asynchronous mold opening between hinge mold segments can also be reduced.

[0031] When the constrained mold segment meets the synchronization recovery condition during subsequent control, the control system releases or adjusts the speed limiting or pause control on the leading hinge mold segment, and re-determines the new constrained mold segment based on the current mold opening displacement parameters, current mold opening response parameters, and current mold opening load parameters of each hinge mold segment. The control system continues to execute synchronous mold opening control according to the new synchronization control benchmark, so that multiple hinge mold segments maintain a controlled displacement difference and load difference during the mold opening process until each hinge mold segment reaches the preset mold opening completion position, thereby completing the mold opening process of the rim mold.

[0032] In the aforementioned synchronous mold opening control process, the control system can determine the constrained mold segment based on the mold opening displacement parameters and mold opening load parameters of each hinge mold segment. Specifically, the control system compares the current mold opening displacement parameters of each hinge mold segment. When the mold opening displacement of one hinge mold segment is less than that of the others, and the mold opening load parameter of that hinge mold segment is higher than the mold opening load parameter before the mold opening command was issued, it indicates that the hinge mold segment has a tendency to be hindered during the mold opening process. In this case, the control system first considers that hinge mold segment as a candidate constrained mold segment, instead of immediately continuing to push all hinge mold segments to open at the normal synchronous mold opening speed. When there are two or more candidate constrained mold segments at the same time, the control system can prioritize the hinge mold segment with smaller mold opening displacement, poorer mold opening response continuity, or higher mold opening load parameter as the candidate constrained mold segment with a higher degree of constraint, and use this candidate constrained mold segment as the priority object for subsequent trial release and synchronous control.

[0033] After identifying the candidate constrained mold segment, the control system performs pre-speed limiting control or pre-pause control on the hinge mold segment that is ahead of the candidate constrained mold segment in mold opening. This temporarily reduces the mold opening speed of the ahead hinge mold segment or stops it from continuing to open, thereby preventing the mold opening displacement difference from continuing to expand. Subsequently, the control system issues a trial release command to the candidate constrained mold segment. The trial release command is used to verify whether the candidate constrained mold segment can resume mold opening motion under relatively small disturbance conditions. The trial release command can be a mold opening drive command with a short duration and low drive output, and its target is the drive mechanism corresponding to the candidate constrained mold segment. The control system detects the mold opening increment of the candidate constrained mold segment within a preset response time and compares the detected mold opening increment with a preset response threshold. At the same time, it checks whether the mold opening load parameter of the candidate constrained mold segment is lower than the mold opening load parameter before issuing the trial release command. The preset response time and preset response threshold can be stored in the control system in advance and determined based on the normal mold opening response speed of the hinge mold segment and the mold debugging results.

[0034] When the opening increment of a candidate constrained module within a preset response time is less than a preset response threshold, and its opening load parameter is not lower than the opening load parameter before the test release command is issued, it indicates that the candidate constrained module has not formed an effective opening motion under the test release action, and the obstruction state has not been relieved. Based on this, the control system identifies the candidate constrained module as a constrained module and uses it as the control benchmark in subsequent synchronous opening control to perform speed limiting or pause control on other hinge modules that are opening ahead of schedule. If the candidate constrained module forms an effective opening motion within a preset response time, and its opening load parameter is lower than the opening load parameter before the test release command is issued, the control system can determine that the obstruction trend of the candidate constrained module has been relieved and continues to control each hinge module according to the current synchronous opening control process.

[0035] In the above embodiment, after determining the constrained mold segment, the control system can set an advance allowable boundary based on the current mold opening displacement parameters, current mold opening response parameters, and current mold opening load parameters of the constrained mold segment. The current mold opening displacement parameters represent the completed mold opening displacement of the constrained mold segment; the current mold opening response parameters represent the displacement change of the constrained mold segment under the control command; and the current mold opening load parameters represent the driving resistance or equivalent load experienced by the constrained mold segment in the current mold opening stage. The control system determines the range of displacement difference that the leading hinge mold segment can maintain relative to the constrained mold segment based on these parameters, and uses this displacement difference range as the advance allowable boundary. This advance allowable boundary can be selected or adjusted by the control system based on the preset displacement difference range of the current mold opening stage, the response state of the constrained mold segment, and the load change state. When the opening displacement of any hinge module reaches the advance allowable boundary, the control system switches the hinge module to a waiting follow state, causing the hinge module to temporarily stop expanding the opening displacement according to the original opening advancement target, until the constrained module generates a new effective opening response, and then the hinge module in the waiting follow state is allowed to continue opening.

[0036] During control, the advance allowable boundary can be dynamically adjusted based on the continuity of the mold opening response of the constrained module. If the constrained module can generate an effective mold opening response throughout the continuous control cycle, it indicates that the constrained module is still in a recoverable mold opening state. The control system can update the advance allowable boundary based on the mold opening changes of the constrained module, allowing the hinged module in the waiting-to-follow state to continue following the mold opening according to the synchronization requirements. If the constrained module does not generate a new effective mold opening response within the continuous control cycle, it indicates that the constrained module may be in a blocked or stuck state. The control system will lock the advance allowable boundary to the current mold opening displacement difference and prohibit the hinged module in the waiting-to-follow state from further increasing the mold opening amount, thereby preventing the mold opening displacement difference between multiple hinged modules from further increasing.

[0037] For hinged modules in a waiting-to-follow state, the control objective shifts from mold opening advancement to maintaining the mold opening displacement difference. In other words, the control system no longer prioritizes increasing the mold opening displacement, but rather maintains the mold opening displacement difference between the hinged module and the constrained module. When the constrained module generates a new effective mold opening response, the control system determines the following increment of the hinged module in the waiting-to-follow state based on the mold opening increment formed by the constrained module within the corresponding control cycle. This following increment is made less than or equal to the mold opening increment of the constrained module, thus allowing the hinged module with the leading mold opening to continue opening based on the recovery motion of the constrained module, preventing the formation of excessive mold opening lead again.

[0038] A new effective mold-opening response can be determined based on both the mold-opening increment of the constrained mold segment and the mold-opening load parameters. The control system detects the mold-opening increment of the constrained mold segment in each control cycle and simultaneously monitors changes in the mold-opening load parameters. When the constrained mold segment generates a mold-opening increment, and the mold-opening load parameters do not increase synchronously relative to the previous control cycle, it can be determined that the mold-opening motion of the constrained mold segment has a recovery trend. Conversely, when the constrained mold segment generates a mold-opening increment, but the mold-opening load parameters increase synchronously relative to the previous control cycle, it indicates that the displacement change of the constrained mold segment may be caused by force compression, structural elastic release, or local loosening, and does not yet indicate that the obstructed state has been relieved. In this case, the control system determines that the constrained mold segment has not generated a new effective mold-opening response and continues to maintain the mold-opening displacement difference of the hinged mold segment in a waiting-to-follow state.

[0039] In the above embodiments, after the control system performs speed limiting control or pause control on the hinged module that is ahead of the constrained module in mold opening, it can further determine whether the constrained module meets the synchronization recovery condition. Specifically, the control system issues a recovery verification command to the constrained module and detects the mold opening response, mold opening load parameters, and mold opening displacement difference between each hinged module during the action of the recovery verification command. If the constrained module produces a mold opening response in the same direction, and the mold opening load parameters of the constrained module have not increased compared to the mold opening load parameters before the issuance of the recovery verification command, and the mold opening displacement difference between each hinged module has not increased, it indicates that the obstruction state of the constrained module has been relieved, and the control system can determine that the constrained module meets the synchronization recovery condition. If any of the above detection results are not met, the control system continues to maintain speed limiting control or pause control on the hinged module that is ahead of the mold opening, and continues to monitor the mold opening state parameters of the constrained module.

[0040] The recovery verification command can be a mold-opening command with an amplitude lower than the reference mold-opening command amplitude during the synchronous mold-opening control process and a duration shorter than the preset duration. By using a recovery verification command with a lower amplitude and shorter duration, the recoverable motion state of the constrained mold segment can be verified without significantly increasing the mold-opening displacement difference. When the constrained mold segment generates a mold-opening response under the action of the recovery verification command, but the mold-opening load parameter of the constrained mold segment increases compared to the mold-opening load parameter before the recovery verification command was issued, it indicates that the mold-opening response has not yet corresponded to load release, and the constrained mold segment may still be in a state of obstruction or off-center loading. At this time, the control system determines that the constrained mold segment has not met the synchronous recovery condition and continues to maintain the speed limiting control or pause control of other hinged mold segments.

[0041] Consistent mold opening responses can be confirmed through two consecutive recovery verification commands. Specifically, the control system sends two consecutive recovery verification commands to the constrained mold segment and detects whether the constrained mold segment produces a mold opening change in the same direction under the action of the two recovery verification commands. If the difference between the two mold opening changes in the same direction is outside the preset difference range, it indicates that the mold opening response stability of the constrained mold segment is insufficient. If the difference in mold opening displacement between each hinge mold segment increases during the verification process, it indicates that the recovery verification may cause an increase in synchronization deviation. In either of the above cases, the control system determines that the constrained mold segment does not meet the synchronization recovery condition.

[0042] When the constrained module responds to the recovery verification command and generates an opening response, but the opening load parameter of the constrained module increases compared to the opening load parameter before the recovery verification command was issued, the control system can reduce the amplitude of the next recovery verification command to reduce the driving disturbance to the constrained module and continue to observe the changes in the opening response and opening load parameter of the constrained module. Only when the opening response of the constrained module reaches the preset response threshold and the opening load parameter is lower than the opening load parameter before the recovery verification command was issued, will the control system release the speed limiting control or pause control of other hinge modules, allowing each hinge module to re-enter the synchronous opening and advancing state.

[0043] Example 1:

[0044] In one embodiment, the control system, in response to the mold opening command of the rim mold, acquires mold opening state parameters for multiple hinge mold segments, including mold opening displacement parameters, mold opening response parameters, and mold opening load parameters. The mold opening displacement parameters represent the degree of opening of the hinge mold segments relative to their initial closed position; the mold opening response parameters represent the displacement change of the hinge mold segments under the control command; and the mold opening load parameters represent the driving resistance or equivalent load experienced by the hinge mold segments during the mold opening process.

[0045] After acquiring the mold opening state parameters of each hinge module segment, the control system compares the mold opening displacement difference and mold opening load difference between the segments. When a hinge module segment lags behind the others in mold opening displacement, and its mold opening load parameter increases compared to the parameter before the mold opening command was issued, the control system first identifies this hinge module segment as a candidate constrained segment. Thus, when a hinge module segment exhibits significant lag and increased load, the control system can prioritize identifying potentially obstructed hinge modules, avoiding the continued pushing of all hinge modules at a uniform mold opening speed.

[0046] like Figure 2As shown, within the same control cycle, the current mold opening displacement and current mold opening load of module segments A, B, C, and D are simultaneously compared and displayed. The mold opening displacement of module segment C is significantly lower than that of the other hinged modules, while its mold opening load is significantly higher than that of the other hinged modules, and also higher than the load level before module segment C issued the mold opening command. This comparison illustrates that the control system does not make judgments solely based on displacement lag or solely based on load increase, but rather uses both mold opening displacement parameters and mold opening load parameters as the basis for identifying candidate constrained modules.

[0047] To facilitate the determination of the degree of lag in the opening displacement of the hinge mold segment, the control system can calculate the following formula: The opening displacement hysteresis of each hinge module segment:

[0048]

[0049] Where represents the lag of the opening displacement of the i-th hinge module, represents the current opening displacement of the i-th hinge module, and represents the reference displacement value among the current opening displacements of multiple hinge modules. The reference displacement value can be the average of the current opening displacements of the remaining hinge modules, or it can be the larger displacement value among the current opening displacements of the remaining hinge modules. The reason for this formula is that the control system needs to compare the current opening displacement of the i-th hinge module with the current opening state of other hinge modules. Therefore, by subtracting the current opening displacement of the i-th hinge module from the reference displacement value, the lag degree of the hinge module relative to the other hinge modules can be obtained.

[0050] For example, a company uses a wheel rim mold with four hinged mold segments, A, B, C, and D. Within a certain control cycle, the current mold opening displacements of A, B, C, and D are 18.6 mm, 18.3 mm, 15.2 mm, and 18.5 mm, respectively, corresponding to mold opening load parameters of 4.8 kN, 4.9 kN, 7.6 kN, and 4.7 kN. The load parameter of mold segment C before the mold opening command is issued is 5.1 kN, with a preset hysteresis threshold of 2.0 mm and a preset response threshold of 0.4 mm. Using the average current mold opening displacement of the three hinged mold segments A, B, and D as the reference displacement value for mold segment C, the calculation is as follows:

[0051]

[0052]

[0053] Since the mold opening displacement lag of module C (3.27 mm) is greater than the preset lag threshold of 2.0 mm, and the mold opening load parameter of module C increases from 5.1 kN before the mold opening command was issued to 7.6 kN, it indicates that module C has a tendency to experience motion resistance during the mold opening process. Based on this, the control system selects module C as a candidate constrained module and performs pre-speed limiting control or pre-pause control on modules A, B, and D that are ahead of module C in mold opening, to prevent modules A, B, and D from further widening the mold opening displacement difference with module C.

[0054] like Figure 3 As shown in the figure, the control system compares the calculated mold opening displacement hysteresis with the preset hysteresis threshold. Mold lobes A, B, and D show small deviations from the reference displacement value and do not exhibit hysteresis exceeding the threshold; however, the mold opening displacement hysteresis of mold lobe C reaches 3.27 mm, significantly exceeding the preset hysteresis threshold of 2.0 mm. This figure further demonstrates that mold lobe C not only... Figure 2 It exhibits low displacement and high load, and meets the triggering conditions for candidate constrained module lobe in the displacement hysteresis determination.

[0055] After identifying a candidate constrained module segment, the control system issues a trial release command to it. This command verifies whether the candidate segment can recover its opening motion under relatively small disturbance conditions. Within a preset response time, the control system detects the opening increment of the candidate segment and compares it with a preset response threshold. Simultaneously, it checks whether the opening load parameter of the candidate segment is lower than the opening load parameter before issuing the trial release command. If the opening increment of the candidate segment within the preset response time is less than the preset response threshold, and the opening load parameter is not lower than the opening load parameter before issuing the trial release command, the control system identifies the candidate segment as a constrained segment.

[0056] After identifying the constrained module segment, the control system sets an advance allowable boundary based on its current mold opening displacement parameters, current mold opening response parameters, and current mold opening load parameters. The advance allowable boundary limits the range of mold opening displacement differences that other hinge modules can maintain relative to the constrained module segment. When any hinge module segment reaches the advance allowable boundary, the control system switches that hinge module segment to a waiting-to-follow state, preventing it from continuing to expand its mold opening displacement according to the original mold opening advancement target, and instead maintaining the mold opening displacement difference with the constrained module segment within a controlled range.

[0057] For a hinged module in a waiting-to-follow state, the control objective shifts from mold opening advancement to maintaining the mold opening displacement difference. In this state, the control system no longer uses increasing the mold opening displacement of the hinged module as the primary control objective, but instead uses limiting the mold opening lead of the hinged module relative to the constrained module as the primary control objective. When the constrained module generates a new effective mold opening response, the control system determines the following increment of the hinged module in the waiting-to-follow state based on the mold opening increment formed by the constrained module within the current control cycle.

[0058] The following increment of the hinge module in the waiting-to-follow state can be determined by the following formula:

[0059]

[0060] in, This indicates the follow-up increment by which the hinged module petal, currently in a waiting-to-follow state, is allowed to continue opening within the current control cycle. This represents the mold opening increment generated by the constrained mold lobe within the current control cycle. Indicates the following coefficient, and The value is greater than 0 and less than or equal to 1. This formula arises because the hinged module in the waiting-to-follow state cannot continue to increase the opening displacement difference between itself and the constrained module; therefore, its following increment should be less than or equal to the opening increment of the constrained module. This is achieved by setting a following coefficient. This allows the hinged mold segments that are ahead of the mold opening to follow in a controlled manner according to the recovery motion of the constrained mold segments.

[0061] For example, during the waiting and following control process, if the C-shaped mold segment forms an effective mold opening increment of 0.6 mm within one control cycle, the following coefficient... If we take 0.8, then the allowed following increment for modules A, B, and D in the waiting-to-follow state is:

[0062]

[0063] Therefore, the allowable follow-up increment for mold segments A, B, and D to continue opening within this control cycle is 0.48 mm, which is less than the opening increment of mold segment C (0.6 mm). Thus, mold segments A, B, and D can continue opening as mold segment C resumes its movement without further increasing their opening lead relative to C, thereby reducing the risk of jamming or uneven loading between multiple hinged mold segments due to asynchronous opening.

[0064] like Figure 4As shown, during the initial control period, the opening increment of module C is lower than the preset response threshold, while the following increments of modules A, B, and D remain zero, corresponding to a waiting-to-follow state. When the opening increment of module C reaches and exceeds the preset response threshold of 0.4 mm, modules A, B, and D continue to open their molds with a following increment smaller than that of module C. This process demonstrates that the waiting-to-follow control does not simply stop other hinge modules, but rather uses the recovery motion of the constrained module as a reference for controlled following after the constrained module recovers its effective opening response.

[0065] The advance allowable boundary can be dynamically adjusted based on the continuity of the mold opening response of the constrained module. If the constrained module can generate new effective mold opening responses within a continuous control cycle, the control system updates the advance allowable boundary according to the mold opening changes of the constrained module, allowing the hinged module in the waiting-to-follow state to continue following the mold opening according to the synchronization requirements. If the constrained module does not generate new effective mold opening responses within a continuous control cycle, the control system locks the advance allowable boundary to the current mold opening displacement difference and prohibits the hinged module in the waiting-to-follow state from increasing the mold opening amount.

[0066] A new effective mold-opening response is determined based on both the mold-opening increment of the constrained mold segment and the mold-opening load parameter. The control system detects the mold-opening increment of the constrained mold segment in each control cycle and simultaneously detects changes in the mold-opening load parameter. When the constrained mold segment generates a mold-opening increment, and the mold-opening load parameter does not increase synchronously relative to the previous control cycle, the control system determines that the constrained mold segment has generated a new effective mold-opening response. When the constrained mold segment generates a mold-opening increment, but its mold-opening load parameter increases synchronously relative to the previous control cycle, the control system determines that the constrained mold segment has not generated a new effective mold-opening response and continues to maintain the mold-opening displacement difference of the hinged mold segment in a waiting-to-follow state.

[0067] Through the above control method, the control system can identify the constrained mold petals during the mold opening process of the rim mold, and use the constrained mold petals as the synchronous control reference to perform waiting and following control on the hinge mold petals that are ahead of the mold opening, so that multiple hinge mold petals maintain a controlled mold opening displacement difference and mold opening load difference during the mold opening process, until the constrained mold petals recover an effective mold opening response before allowing other hinge mold petals to follow the mold opening.

[0068] Example 2:

[0069] In one implementation, after identifying the constrained mold segment during synchronous mold opening control, the control system performs speed limiting control or pause control on the hinge mold segment that is ahead of the constrained mold segment in mold opening. The hinge mold segment under speed limiting control or pause control will no longer continue to expand the mold opening displacement according to the original synchronous mold opening advancement target, and the control system will use the recovery state of the constrained mold segment as the basis for determining whether to re-enter the synchronous mold opening advancement state.

[0070] The control system issues a recovery verification command to the constrained mold segment and, during the execution of the recovery verification command, detects the mold opening response, mold opening load parameters, and mold opening displacement difference between each hinge mold segment. The recovery verification command is used to verify whether the constrained mold segment has met the conditions for resynchronizing mold opening without significantly increasing the mold opening displacement difference between multiple hinge mold segments.

[0071] The recovery verification command is a mold opening command with an amplitude lower than the reference mold opening command amplitude during the synchronous mold opening control process and a duration shorter than a preset time. To facilitate determining the amplitude of the recovery verification command, the control system can be set according to the following formula:

[0072]

[0073] in, This indicates the magnitude of the recovery verification command. This represents the amplitude of the reference mold opening command during the synchronous mold opening control process. This indicates the verification amplitude coefficient, and Greater than 0 and less than 1. The reason for this formula is that the recovery verification command is only used to test whether the constrained mold lobe has recovered its mold-opening capability; its amplitude should be lower than the baseline mold-opening command amplitude during normal synchronous mold opening. The amplitude coefficient is verified through this process. Reducing the amplitude of the baseline mold opening command can decrease the disturbance to the mold synchronization state caused by the recovery verification.

[0074] For example, the reference mold opening command amplitude during the synchronous mold opening process of the wheel rim mold used by a certain company. The amplitude coefficient is 10.0V. If we take 0.35, then the amplitude of the recovery verification command is:

[0075]

[0076] In this operating condition, the duration of the recovery verification command is 0.25s, while the preset duration is 0.50s. Therefore, the duration of the recovery verification command is less than the preset duration. The control system uses a 3.5V recovery verification command applied to the constrained module, resulting in a smaller mold opening drive disturbance for the constrained module, while simultaneously maintaining the speed limiting control or pause control state of other mold opening leading hinge modules. Figure 5 As shown, there is a significant difference between the amplitude of the reference mold opening command and the amplitude of the recovery verification command. The recovery verification command is only a low-amplitude probe signal, and its duration is shorter than the preset duration. This intuitively shows that the recovery verification does not directly restore the full-amplitude mold opening drive, but confirms the recoverable motion state of the constrained mold lobe under relatively small disturbance conditions.

[0077] When the constrained module produces a consistent mold-opening response under the action of the recovery verification command, and the mold-opening load parameter of the constrained module has not increased compared to the mold-opening load parameter before the issuance of the recovery verification command, and the mold-opening displacement difference between each hinge module has not increased, the control system determines that the constrained module meets the synchronous recovery condition. A consistent mold-opening response means that the constrained module produces mold-opening changes in the same direction under the action of two consecutive recovery verification commands.

[0078] To facilitate the assessment of the mold opening response stability under two consecutive recovery verification commands, the control system can calculate the difference between the two recovery verification responses using the following formula:

[0079]

[0080] in, This represents the difference between the two recovery verification responses. This represents the mold opening response of the constrained mold lobe under the first recovery verification command. This represents the mold opening response of the constrained module under the second recovery verification command. The reason for this formula is that if the constrained module produces mold opening changes in the same direction under two consecutive recovery verification commands, but the difference between the two mold opening response quantities is too large, it indicates that the response stability of the constrained module is insufficient. Therefore, the difference between the two response quantities is used to determine whether it is within the preset difference range.

[0081] In two consecutive recovery verifications, the first mold opening response of the constrained mold lobe The second mold opening response amount is 0.42mm. The difference is 0.46mm, and the preset upper limit of the difference range is 0.10mm. Therefore, the difference between the two recovery verification responses is:

[0082]

[0083] Since the difference between the two recovery verification responses (0.04 mm) is less than the upper limit of the preset difference range (0.10 mm), it indicates that the mold opening response of the constrained mold segment under the action of the two recovery verification commands is stable. Figure 6 As shown, the mold opening response values ​​of the first and second verifications are significantly higher than the response difference, and the response difference calculated from the two response values ​​is lower than the upper limit of the difference range. This indicates that the constrained mold flap is not an occasional loosening or instantaneous elastic release, but exhibits a relatively stable unidirectional mold opening response in continuous verification.

[0084] If simultaneously the opening load parameter of the constrained module segment decreases from 7.2kN before recovery verification to 6.5kN, and the maximum opening displacement difference between each hinge module segment does not increase, the control system determines that the constrained module segment meets the synchronous recovery condition and releases the speed limiting control or pause control of other hinge module segments, allowing multiple hinge module segments to re-enter the synchronous opening and advancing state. Figure 7 As shown, during the recovery verification phase, the mold opening load parameter gradually decreased from 7.2kN to 6.5kN, and the maximum mold opening displacement difference remained at or decreased from 3.1mm to 3.0mm, indicating that the load state of the constrained mold segment was released, and the verification process did not cause an increase in the synchronous deviation between the hinge mold segments.

[0085] When the constrained module responds to the recovery verification command and generates an opening response, but the opening load parameter of the constrained module increases compared to the opening load parameter before the recovery verification command was issued, it indicates that the opening response has not yet corresponded to load release, and the constrained module may still be in a state of obstruction or off-center loading. At this time, the control system determines that the constrained module has not met the synchronous recovery condition and maintains speed limiting control or pause control for other hinged modules.

[0086] In another operating condition, if the constrained module produces an opening response under the action of the recovery verification command, but the opening load parameter increases from 7.2kN before recovery verification to 7.8kN, the control system reduces the amplitude of the next recovery verification command to reduce the driving disturbance to the constrained module and continues to monitor the opening response and changes in the opening load parameter of the constrained module. Only when the opening response of the constrained module reaches the preset response threshold and the opening load parameter is lower than the opening load parameter before the recovery verification command is issued, will the control system release the speed limiting control or pause control of other hinge modules.

[0087] When the constrained module undergoes unidirectional mold opening changes under two consecutive recovery verification commands, but the difference between the two unidirectional mold opening changes is outside the preset difference range, the control system determines that the constrained module has not met the synchronous recovery condition. When the mold opening displacement difference between each hinge module expands during the verification process, it indicates that the recovery verification may cause an increase in synchronization deviation. The control system also determines that the constrained module has not met the synchronous recovery condition and continues to maintain speed limiting control or pause control.

[0088] In this way, the control system uses low-amplitude, short-duration recovery verification commands to verify the constrained module petals. It also combines three conditions—consistent mold opening response, no increase in mold opening load parameters, and no expansion of mold opening displacement difference—to determine the synchronous recovery state. This ensures that other hinged module petals only release speed limiting control or pause control after the constrained module petals have a stable mold opening capability, thereby reducing the risk of mold opening asynchrony, off-center load, or jamming during the recovery process.

Claims

1. A method for synchronously controlling the hinge opening of an openable rim mold, characterized in that, include: In response to the mold opening command, the mold opening state parameters of multiple hinge mold segments are obtained. The mold opening state parameters include mold opening displacement parameters, mold opening response parameters, and mold opening load parameters. Based on the mold opening state parameters of each hinge mold segment, it is determined whether each hinge mold segment meets the synchronous mold opening conditions. After each hinge mold segment meets the synchronous mold opening conditions, the synchronous mold opening control process is entered. During the synchronous mold opening control process, based on the mold opening displacement difference and mold opening load difference between each hinge mold piece, a constrained mold piece is determined from multiple hinge mold pieces. The constrained mold piece is used as the synchronous control reference, and speed limiting control or pause control is performed on the hinge mold pieces that are ahead of the mold opening relative to the constrained mold piece, so as to limit the expansion of the mold opening displacement difference between each hinge mold piece. Once the constrained mold segment meets the synchronous recovery condition, the constrained mold segment is redefined and the synchronous mold opening control process continues until each hinge mold segment reaches the preset mold opening completion position.

2. The hinge-based synchronous control method for opening a rim mold according to claim 1, characterized in that, The constrained module segment is determined as follows: when a hinge module segment lags behind the other hinge module segments in terms of opening displacement, and the opening load parameter of the hinge module segment increases compared to the opening load parameter before the opening command is issued, the hinge module segment is selected as a candidate constrained module segment. After the control system performs pre-speed limiting control or pre-pause control on the hinge module that is ahead of the candidate constrained module in mold opening, it issues a trial release command to the candidate constrained module. If the mold opening increment of the candidate constrained module within a preset response time is less than a preset response threshold, and the mold opening load parameter is not lower than the mold opening load parameter before the trial release command is issued, then the candidate constrained module is determined to be a constrained module.

3. The hinge-based synchronous control method for opening a rim mold according to claim 1, characterized in that, The speed limiting control or pause control is as follows: a leading allowable boundary is set according to the current mold opening displacement parameters, current mold opening response parameters, and current mold opening load parameters of the constrained mold segment; when any hinge mold segment reaches the leading allowable boundary, the hinge mold segment is switched to a waiting follow state; the hinge mold segment in the waiting follow state continues to open the mold after the constrained mold segment generates a new effective mold opening response.

4. The hinge-based synchronous control method for opening a rim mold according to claim 1, characterized in that, The synchronization recovery condition is as follows: when the hinged module that is ahead of the constrained module in mold opening is under speed limiting control or pause control, the control system sends a recovery verification command to the constrained module; when the constrained module generates a mold opening response in the same direction, the mold opening load parameter of the constrained module has not increased compared with the mold opening load parameter before the recovery verification command was issued, and the mold opening displacement difference between each hinged module has not increased, it is determined that the constrained module meets the synchronization recovery condition.

5. The hinge-based synchronous control method for opening a rim mold according to claim 3, characterized in that, The advance allowable boundary is dynamically adjusted according to the continuity of the mold opening response of the constrained mold lobe; when the constrained mold lobe does not generate a new effective mold opening response within a continuous control cycle, the advance allowable boundary is locked to the current mold opening displacement difference, and the hinged mold lobe in the waiting follow state is prohibited from expanding the mold opening amount.

6. The hinge-based synchronous control method for opening a rim mold according to claim 3, characterized in that, For the hinged module in the waiting-to-follow state, the control target is switched from mold opening advancement to mold opening displacement difference maintenance; when the constrained module generates a new effective mold opening response, the hinged module in the waiting-to-follow state continues to open the mold according to a following increment that is less than or equal to the mold opening increment of the constrained module.

7. The hinge-based synchronous control method for opening a rim mold according to claim 3, characterized in that, The new effective mold opening response is determined based on the mold opening increment and the mold opening load parameter. When the constrained mold segment generates a mold opening increment, but the mold opening load parameter of the constrained mold segment increases synchronously with the previous control cycle, the control system determines that the constrained mold segment has not generated a new effective mold opening response and maintains the mold opening displacement difference of the hinged mold segment in the waiting follow state.

8. The hinge-based synchronous control method for opening a rim mold according to claim 4, characterized in that, The recovery verification command is a mold opening command with an amplitude lower than the reference mold opening command amplitude in the synchronous mold opening control process and a duration less than the preset duration. When the constrained module generates a mold opening response under the action of the recovery verification command, but the mold opening load parameter of the constrained module increases relative to the mold opening load parameter before the recovery verification command is issued, the control system determines that the constrained module does not meet the synchronous recovery condition and maintains the speed limiting control or pause control of other hinge modules.

9. The hinge-based synchronous control method for opening a rim mold according to claim 4, characterized in that, The consistent mold opening response means that the constrained mold lobe produces a mold opening change in the same direction under two consecutive recovery verification commands; when the difference between the two mold opening changes in the same direction is outside the preset difference range, or when the difference in mold opening displacement between each hinge mold lobe increases, the control system determines that the constrained mold lobe does not meet the synchronous recovery condition.

10. The hinge-based synchronous control method for opening a rim mold according to claim 8, characterized in that, When the constrained module generates an opening response under the action of the recovery verification command, but the opening load parameter of the constrained module increases relative to the opening load parameter before the recovery verification command is issued, the control system reduces the amplitude of the next recovery verification command, and releases the speed limiting control or pause control of other hinge modules after the opening response amount of the constrained module reaches the preset response threshold and the opening load parameter is lower than the opening load parameter before the recovery verification command is issued.

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