Aluminum alloy die-casting cooling control method based on mold temperature timing prediction

Abstract

This invention relates to the field of cooling control technology and discloses a cooling control method for aluminum alloy die casting based on mold temperature time sequence prediction. It is applied to aluminum alloy die casting molds equipped with temperature measuring points and cooling channels. The connection state between the cooling medium and the cooling channels can be controlled. The method includes: obtaining the point temperature of the measuring point at multiple sampling times and forming a point temperature time sequence according to the sampling time; predicting the next point temperature at the next sampling time based on the point temperature change trend; forming a cooling channel control result acting on at least one cooling channel based on the next point temperature, and determining the cooling channel as the target cooling channel; and executing the cooling channel control result to change or maintain the connection state between the cooling medium and the target cooling channel. This invention is used to implement the point temperature change trend and the next point temperature into the on / off control of the cooling medium.

Description

Technical Field

[0001] This invention relates to the field of cooling control technology, and more specifically, to a cooling control method for aluminum alloy die casting based on mold temperature timing prediction. Background Technology

[0002] In aluminum alloy die casting production, the spot temperature continuously changes with the injection, solidification, and demolding cycles. Production lines typically arrange temperature measuring points on the mold and introduce cooling media through cooling channels to cool the area near the cavity. On-site control often relies on the obtained spot temperature, manual experience, or fixed cycle rules to determine whether the cooling media enters the corresponding cooling channel. This method is prone to delays in control action compared to the spot temperature change when the temperature rise is rapid, the heat load distribution changes frequently, or the effective areas of different cooling channels differ significantly. This results in untimely localized cooling intervention within the same die casting cycle, requiring subsequent compensation by extending the cooling time or adjusting process conditions, which increases the difficulty of cycle management. For aluminum alloy die casting molds with existing temperature measuring points, cooling channels, and controllable connectivity, there is a greater need for a control method that can use the spot temperature change trend formed over the sampling time for cooling media on / off decisions, so that cooling channel control before the next sampling time no longer relies solely on the obtained spot temperature. Summary of the Invention

[0003] This invention provides a cooling control method for aluminum alloy die casting based on mold temperature timing prediction, which solves the technical problems mentioned in the background art.

[0004] To achieve the above-mentioned objectives, the present invention provides the following technical solution.

[0005] A cooling control method for aluminum alloy die casting based on mold temperature time-series prediction is applied to an aluminum alloy die casting mold. The aluminum alloy die casting mold is equipped with temperature measuring points and cooling channels, and the communication state between the cooling medium and the cooling channels can be controlled. The method includes:

[0006] The point temperature of the temperature measuring point is obtained at multiple sampling times, and the point temperature of the same temperature measuring point is formed into a point temperature time sequence according to the sampling time. The point temperature time sequence is used to characterize the point temperature change trend of the temperature measuring point as the sampling time changes.

[0007] Based on the temperature change trend, predict the next temperature at the next sampling time.

[0008] Based on the cooling channel control result of the next point temperature formation acting on at least one of the cooling channels, and the cooling channel acting on the cooling channel control result is determined as the target cooling channel, the cooling channel control result is used to indicate whether the communication state between the cooling medium and the target cooling channel changes or remains before the next sampling time;

[0009] The cooling channel control result is executed, so that the connection state between the cooling medium and the target cooling channel is changed or maintained according to the cooling channel control result.

[0010] Compared with the prior art, the present invention has the following substantial features and significant progress:

[0011] This invention establishes a temperature sequence based on the sampling time of the spot temperature of the aluminum alloy die-casting mold, and obtains the next spot temperature before the next sampling time arrives. This allows the cooling channel control results to directly affect the connectivity of the target cooling channel, reducing the lag caused by adjusting the cooling medium supply based solely on the obtained spot temperature. The connectivity, disconnection, or maintenance of the cooling medium and cooling channel can be adjusted in advance according to the trend of spot temperature changes, thereby making the mold cooling control more closely match the temperature rise process in the die-casting cycle, and providing a unified control entry point for subsequent selection of cooling channels through standard spot temperatures, registration of corresponding relationships, or heating zones. Attached Figure Description

[0012] Figure 1 This is a control mechanism diagram of an aluminum alloy die casting cooling control method based on mold temperature timing prediction according to the present invention. Detailed Implementation

[0013] The following description is provided in conjunction with the accompanying drawings. It should be understood that the following embodiments are for illustrative purposes only and are not intended to limit the invention; those skilled in the art can make equivalent substitutions or combinations for the specific implementations.

[0014] The following combination Figure 1 A specific description is provided of a cooling control method for aluminum alloy die casting based on mold temperature time-series prediction. The aluminum alloy die casting mold is equipped with temperature measuring points and cooling channels, and the communication state between the cooling medium and the cooling channels can be controlled. See also... Figure 1 The aluminum alloy die-casting mold 100 is provided with a temperature measuring point 110 and a cooling channel 120. The cooling medium supply unit 130 is connected to the cooling channel 120 through a connecting control component 140. The controller 150 is used to obtain the point temperature, form the point temperature sequence, predict the next point temperature, and form the cooling channel control result.

[0015] This embodiment is applicable to situations in aluminum alloy die casting production where the flow of cooling medium into cooling channel 120 needs to be adjusted within the die casting cycle. The aluminum alloy die casting mold 100 is subjected to cyclical thermal loads during injection, solidification, and demolding, and the point temperature obtained at temperature measurement point 110 changes with the sampling time. If the connection between the cooling medium and cooling channel 120 is controlled solely according to the already obtained point temperature or a fixed cycle rule, the flow of cooling medium into the target cooling channel tends to lag behind the point temperature change.

[0016] The control chain in this embodiment is based on the temperature change trend formed by the change of point temperature with sampling time. Before the next sampling time arrives, the next point temperature is obtained. Then, based on the next point temperature, a cooling channel control result is formed that acts on at least one cooling channel 120, and the cooling channel 120 acted upon by the cooling channel control result is determined as the target cooling channel. The controller 150 executes the cooling channel control result, so that the connection state between the cooling medium and the target cooling channel is changed or maintained according to the cooling channel control result.

[0017] See Figure 1 The point temperature timing formation unit 160 receives the point temperature from the temperature measurement point 110 and forms a point temperature timing sequence for the same temperature measurement point 110 according to the sampling time. The next point temperature prediction unit 170 obtains the next point temperature based on the point temperature change trend represented by the point temperature timing sequence. The cooling channel control result formation unit 180 forms a cooling channel control result based on the next point temperature and outputs the executable cooling channel control result to the communication control element 140 through the controller 150. After the communication control element 140 executes, the communication state between the cooling medium supply unit 130 and the target cooling channel is actually changed or maintained.

[0018] See Figure 1 The aluminum alloy die-casting mold 100 is the controlled object, and multiple temperature measuring points 110 are provided inside or near the cavity wall. The temperature measuring points 110 are used to obtain the point temperature at that location at the sampling time. The temperature measuring points 110 can be formed by thermocouples with existing temperature measuring holes installed in the aluminum alloy die-casting mold 100, or by equivalent temperature measuring components capable of obtaining point temperatures; regardless of the type of temperature measuring component used, the controller 150 receives the point temperature obtained by the temperature measuring point 110 at the corresponding sampling time.

[0019] The aluminum alloy die-casting mold 100 is also provided with a cooling channel 120, which is used for the passage of cooling medium to remove heat from the corresponding area of ​​the aluminum alloy die-casting mold 100. A cooling medium supply unit 130 is located outside the aluminum alloy die-casting mold 100, and its output end is connected to the cooling channel 120 via a communication control element 140. The communication control element 140 is disposed between the cooling medium supply unit 130 and the cooling channel 120, allowing the communication state between the cooling medium and the cooling channel 120 to be controlled.

[0020] The connectivity state includes a connected state where the cooling medium can enter the cooling channel 120, and a disconnected state where the cooling medium cannot enter the cooling channel 120. The cooling channel control result can indicate that the connectivity state changes from disconnected to connected, or from connected to disconnected, or it can indicate that the connectivity state remains unchanged. Regardless of whether the connectivity control component 140 uses a solenoid valve, proportional valve, or other component capable of controlling the flow of the cooling medium, the result after execution is based on whether the connectivity state between the cooling medium and the target cooling channel changes or remains unchanged.

[0021] The controller 150 can be an existing controller in the die-casting production line, or it can be an industrial controller that can read the temperature of the temperature measuring point 110 and output a control signal to the connected control unit 140. The controller 150 includes at least a temperature timing formation unit 160, a next temperature prediction unit 170, and a cooling channel control result formation unit 180.

[0022] During the die-casting production process, the controller 150 acquires the point temperature of the temperature measuring point 110 at multiple sampling times. The sampling time can be determined by a fixed time interval in the die-casting cycle, or by a predetermined timing sequence after the mold closing signal or the injection start signal. For this embodiment, the key is that the controller 150 can acquire the point temperature of the same temperature measuring point 110 at multiple sampling times, so that the point temperature is organized into data that can characterize the trend of point temperature change according to the sampling time.

[0023] After acquiring the point temperatures, the point temperature timing formation unit 160 forms a point temperature timing sequence based on the sampling time of the same temperature measurement point 110. The point temperature timing sequence is for the same temperature measurement point 110, and the arrangement is based on the sampling time. One temperature measurement point 110 corresponds to one point temperature timing sequence, and multiple temperature measurement points 110 form their own separate point temperature timing sequences. This avoids the point temperatures of different temperature measurement points 110 from being mixed into the same prediction relationship, enabling the next point temperature prediction unit 170 to predict the next point temperature of the same temperature measurement point 110 at the next sampling time based on the point temperature change trend of the same temperature measurement point 110.

[0024] In one specific implementation, the controller 150 acquires the point temperatures of all temperature measurement points 110 at each sampling time. After acquiring the point temperatures of all temperature measurement points 110, the controller 150 distinguishes different temperature measurement points 110 according to their sequence numbers and writes the point temperature and sampling time of the same temperature measurement point 110 into the corresponding point temperature window. The point temperature window retains multiple consecutive point temperatures arranged according to the sampling time, and the order of the point temperatures in the point temperature window is consistent with the order of the sampling time.

[0025] The point temperature window is used to store the point temperature obtained from the same temperature measurement point 110 during continuous sampling time. Since the point temperature window stores both the point temperature and the sampling time, the next point temperature prediction unit 170 can obtain the rate of change of adjacent point temperatures from the point temperature difference between adjacent sampling times. When the point temperature window stores multiple consecutive point temperatures, the point temperature timing formation unit 160 can update the point temperature window after each new point temperature is obtained, so that the point temperature window always reflects the point temperature changes during the most recent continuous sampling time.

[0026] The point temperature timing sequence is used to characterize the point temperature change trend of the temperature measuring point 110 over the sampling time. The point temperature change trend is the relationship between the point temperature changes of the same temperature measuring point 110 at multiple sampling times. The controller 150 predicts the next point temperature at the next sampling time based on this point temperature change trend, so that the cooling channel control result forming unit 180 obtains a basis for controlling the connection state between the cooling medium and the target cooling channel before the next sampling time.

[0027] The point temperature timing sequence output by the point temperature timing formation unit 160 may include five consecutive point temperatures, or it may include other numbers of consecutive point temperatures. Specifically, it is implemented by storing five consecutive point temperatures in a point temperature window. When the point temperature window stores five consecutive point temperatures, the next point temperature prediction unit 170 can obtain the rate of change of the four most recent adjacent point temperatures, and further obtain the average rate of change of the point temperature.

[0028] The next point temperature prediction unit 170 predicts the next point temperature of the temperature measuring point 110 at the next sampling time based on the point temperature change trend in the point temperature time series. The next point temperature is the input of the cooling channel control result formation unit 180, and its technical significance lies in advancing the cooling control basis from the already obtained point temperature to the point temperature corresponding to the next sampling time. Since it takes a certain amount of time for the cooling medium to enter the target cooling channel and change the local cooling effect of the aluminum alloy die-casting mold 100, the next point temperature enables the cooling channel control result to be formed before the next sampling time.

[0029] When five consecutive point temperatures are stored in the point temperature window, the next point temperature prediction unit 170 obtains the rate of change of adjacent point temperatures based on the point temperatures corresponding to adjacent sampling times. The rate of change of adjacent point temperatures reflects how quickly the point temperature of the same temperature measurement point 110 changes between adjacent sampling times. For temperature measurement point number 110... Temperature measurement point 110, at the current sampling time is In this case, the rate of temperature change of the four most recent adjacent points can be obtained by the following formula.

[0030]

[0031] In the formula, The temperature measurement point number is Temperature measurement point 110 at the current sampling time The rate of temperature change at the corresponding adjacent points. Sampling number. Used to distinguish between multiple sampling times Indicates the current sampling time. and This represents the time intervals between two adjacent sampling points used to obtain the rate of temperature change at adjacent points.

[0032] In the formula, and These represent the temperature measurement point numbers. The temperature of the measurement point 110 was obtained at two adjacent sampling times. This indicates that the four most recent adjacent sampling times are taken from the current sampling time backward.

[0033] After obtaining the temperature change rates of the four most recent adjacent points, the next point temperature prediction unit 170 averages the temperature change rates of the four most recent adjacent points to obtain the average point temperature change rate. The average point temperature change rate is used to reduce the impact of short-term fluctuations in point temperature within a single adjacent sampling time on the next point temperature, so that the next point temperature can reflect the overall point temperature change trend represented by the point temperature time series.

[0034]

[0035] In the formula, The temperature measurement point number is Temperature measurement point 110 at the current sampling time The rate of change of the average point temperature. This represents one of the most recent four adjacent temperature change rates. The average is limited to the most recent four adjacent temperature change rates, corresponding to the implementation of storing five consecutive temperature points in the temperature window.

[0036] After obtaining the average point temperature change rate, the next point temperature prediction unit 170 predicts the next point temperature based on the last point temperature in the point temperature window and the average point temperature change rate. The last point temperature in the point temperature window corresponds to the current sampling time, the average point temperature change rate is used to represent the point temperature change trend near the current sampling time, and the sampling time interval used to predict the next point temperature represents the interval between the current sampling time and the next sampling time.

[0037]

[0038] In the formula, The temperature measurement point number is Temperature measurement point 110 at the next sampling time The next bit of warmth. This indicates that temperature measurement point 110 was at the current sampling time. The temperature at the point. This indicates the rate of change of the average point temperature. This indicates the sampling time interval used to predict the next point temperature.

[0039] Through the above processing, the next point temperature output by the next point temperature prediction unit 170 corresponds one-to-one with the temperature measurement point 110.

[0040] The cooling channel control result forming unit 180 generates a cooling channel control result corresponding to the target cooling channel based on the next point temperature. The target cooling channel is the cooling channel 120 affected by the cooling channel control result. The cooling channel control result is used to indicate whether the connection state between the cooling medium and the target cooling channel changes or remains unchanged before the next sampling time.

[0041] In one specific embodiment, the controller 150 acquires a standard point temperature corresponding to the temperature measurement point 110. The standard point temperature can be written into the controller 150 from aluminum alloy die casting process documents, aluminum alloy die casting mold 100 debugging documents, or production control configuration. The standard point temperature is used to compare with the next point temperature, thereby enabling the cooling channel control result forming unit 180 to determine whether the target cooling channel needs to allow the cooling medium to enter.

[0042] When the current point temperature is higher than the standard point temperature, the cooling channel control result forming unit 180 forms a cooling channel control result to connect the cooling medium with the target cooling channel. At this time, the target cooling channel is the target cooling channel. After execution, the cooling medium can enter the target cooling channel through the cooling medium supply unit 130 and the connection control element 140, so that the corresponding area of ​​the target cooling channel receives the action of the cooling medium before the next sampling time.

[0043] When the current point temperature is not higher than the standard point temperature, the cooling channel control result forming unit 180 forms a cooling channel control result to disconnect or keep disconnected between the cooling medium and the target cooling channel. This cooling channel control result also acts on the target cooling channel, and after execution, the connection between the cooling medium and the target cooling channel is disconnected or kept disconnected according to the cooling channel control result.

[0044] When one target cooling channel corresponds to one temperature measuring point 110, the cooling channel control result forming unit 180 compares the next temperature of the measuring point 110 with the standard temperature corresponding to the measuring point 110. When one target cooling channel corresponds to multiple temperature measuring points 110, the cooling channel control result forming unit 180 obtains the next temperature and the corresponding standard temperature of each of the multiple measuring points 110. When the next temperature of at least one measuring point 110 is higher than the corresponding standard temperature, a cooling channel control result is formed to connect the cooling medium to the target cooling channel. When the next temperature of all measuring points 110 is not higher than the corresponding standard temperature, a cooling channel control result is formed to disconnect or keep disconnected from the target cooling channel.

[0045] In one specific embodiment, the controller 150 pre-establishes a registration correspondence. This registration correspondence records the relationship between each cooling channel 120 and one or more temperature measuring points 110. The registration correspondence can be established during the commissioning phase of the aluminum alloy die-casting mold 100 based on the relative positions of the temperature measuring points 110 and the cooling channels 120, or it can be established based on the working area of ​​the cooling channels 120 and the area where the temperature measuring points 110 are located in the design data of the aluminum alloy die-casting mold 100.

[0046] The purpose of registering the correspondence is to connect the next temperature point of temperature measurement point 110 to the cooling channel 120. The temperature point timing formation unit 160 and the next temperature point prediction unit 170 obtain the next temperature point corresponding to temperature measurement point 110, while the connection control unit 140 actually controls the connection state between the cooling medium and the cooling channel 120. The cooling channel control result formation unit 180 determines the target cooling channel according to the registered correspondence, so that the next temperature point can act on the cooling channel 120 corresponding to the temperature measurement point 110.

[0047] When the registration relationship records that one cooling channel 120 corresponds to one temperature measuring point 110, the cooling channel 120 can determine whether to be used as a target cooling channel based on the next temperature of the temperature measuring point 110. When the registration relationship records that one cooling channel 120 corresponds to multiple temperature measuring points 110, the cooling channel 120 can jointly determine whether to be used as a target cooling channel based on the next temperature of the multiple temperature measuring points 110.

[0048] After determining the target cooling channel based on the registration correspondence, the cooling channel control result forming unit 180 generates a cooling channel control result acting on the target cooling channel. This cooling channel control result may include the cooling channel number of the target cooling channel, or it may be directly pointed to by the output port correspondence inside the controller 150; enabling the connectivity control element 140 to identify the target cooling channel that needs to be changed or kept connected.

[0049] In addition to determining the target cooling channel based on the registered correspondence, this embodiment can also pre-register the temperature measurement point positions within the same mold coordinate system before forming the cooling channel control result. The temperature measurement point position indicates the location of the temperature measurement point 110 within the same mold coordinate system. By placing multiple temperature measurement point positions within the same mold coordinate system, the controller 150 can compare the spatial distribution of the currently obtained temperature point and the next temperature point within the coordinate domain where the mold cavity wall is located.

[0050] The controller 150 triangulates the coordinate domain of the mold cavity wall based on the location of the temperature measuring point. The triangles formed by the triangulation use the temperature measuring point as the vertex or the temperature measuring point as the temperature surface construction node, so that the coordinate domain of the mold cavity wall is divided into multiple triangles that can be linearly interpolated.

[0051] Within the triangle formed by triangulation, the controller 150 performs linear interpolation on the currently acquired point temperature to form the current temperature surface. The current temperature surface represents the temperature surface determined by the point temperatures of multiple temperature measurement points 110 within the coordinate domain of the mold cavity wall at the current sampling time. (Regarding the coordinate domain position...) The current temperature surface can be represented by the following formula.

[0052]

[0053] In the formula, Indicates the position of the coordinate domain At the current sampling time The current temperature surface. This represents the coordinate domain where the mold cavity wall is located. This indicates the coordinate domain position within the coordinate domain where the mold cavity wall is located. Indicates the position of the coordinate domain The set of temperature measurement point indices at the vertices of the triangle. This represents the linear interpolation weight.

[0054] Linear interpolation weights are determined by the coordinate domain position. The position is determined within the corresponding triangle. For positions within the same coordinate domain... The current temperature surface and the next temperature surface use the same triangle and the same linear interpolation weights, so that the difference between the current temperature surface and the next temperature surface comes from the point temperature and the next point temperature.

[0055] The controller 150 also performs linear interpolation on the next temperature point within the same triangle to form the next temperature surface. The next temperature surface represents the temperature surface determined by the next temperature point of multiple temperature measuring points 110 within the coordinate domain where the mold cavity wall is located at the next sampling time. For the same coordinate domain position... The next temperature surface can be represented by the following formula.

[0056]

[0057] In the formula, Indicates the position of the coordinate domain Next sampling time The next warm side. The temperature measurement point number is Temperature measurement point 110 is the next temperature point at the next sampling time. Since the current temperature surface and the next temperature surface use the same mold coordinate system, the same coordinate domain of the mold cavity wall, and the same triangle, they can be directly compared.

[0058] The controller 150 defines the coordinate domain position where the next temperature surface is higher than the current temperature surface as the heating zone. The heating zone reflects the spatial result formed by the point temperature change trend from the current sampling time to the next sampling time within the coordinate domain of the mold cavity wall. The heating zone is used to participate in determining the target cooling channel, so that the cooling channel control result can be determined not only from the registered correspondence, but also by combining the change position of the next temperature surface relative to the current temperature surface.

[0059]

[0060] In the formula, Indicates the current sampling time The heating zone is determined based on the current temperature surface and the next temperature surface. This represents the coordinate domain where the mold cavity wall is located. This formula includes the coordinate domain where the next temperature surface is higher than the current temperature surface into the heating zone, so that the heating zone directly corresponds to the spatial change of the next point temperature.

[0061] After determining the heating zone, the controller 150 identifies the non-connected portions within that heating zone as connected heating zones for determining the target cooling channel. A connected heating zone is a single connected portion within the heating zone, and different connected heating zones are not interconnected within the coordinate domain of the mold cavity wall. Through this process, multiple heating locations occurring simultaneously within a single die-casting cycle can each participate in determining the target cooling channel.

[0062] In its implementation, the controller 150 can identify connected heating regions based on the adjacency relationships formed by triangulation. When adjacent triangles or adjacent coordinate domains belonging to a heating region are connected to each other, they are identified as the same connected heating region; unconnected parts are identified as different connected heating regions.

[0063] The connected heating zones are used to determine the target cooling channels. For each connected heating zone, the controller 150 subsequently determines the center of the heating zone, the nearest point of the cooling channel, and the distance to the nearest point of the cooling channel, and selects the target cooling channel accordingly. In this way, when the heating zone is spatially divided into multiple parts, the cooling channel control result forming unit 180 can form cooling channel control results acting on the corresponding target cooling channels for different connected heating zones.

[0064] When determining the target cooling channel based on the connected heating zone, the controller 150 pre-registers the cooling channel direction of each cooling channel 120. The cooling channel direction represents the centerline coordinates of the cooling channel 120 within the same mold coordinate system. The cooling channel direction is different from the cooling channel 120 itself. The cooling channel 120 is the physical channel through which the cooling medium passes, while the cooling channel direction is the geometric expression of the cooling channel 120 used for spatial calculation within the same mold coordinate system.

[0065] For each connected heating zone, the controller 150 determines the center of that heating zone. The center of the heating zone can be determined using the geometric center of the connected heating zone, representing its spatial position within the coordinate domain of the mold cavity wall. The center of the heating zone serves as a reference position for establishing a spatial correspondence between the connected heating zone and the cooling channel direction.

[0066]

[0067] In the formula, The serial number of the connected heating zone is indicated as follows: The center of the heating zone corresponding to the connected heating zone. Indicates the warming zone The serial number of the heating zone in the central connection is The connected heating zone. This represents the area of ​​the connected heating zone. This indicates the coordinate domain position within the coordinate domain where the mold cavity wall is located.

[0068] After determining the center of the heating zone, the controller 150 determines the nearest point of each cooling channel to the center of the heating zone along the direction of each cooling channel, and determines the distance from the nearest point of each cooling channel to the center of the heating zone. The nearest point of each cooling channel and the distance between the nearest points are used to measure the spatial proximity of each cooling channel 120 relative to the connected heating zone.

[0069]

[0070] In the formula, Indicates the cooling channel number is The cooling channel 120 is numbered relative to the connected heating zone as follows: The nearest point to the cooling channel connecting the heating zone. Indicates the cooling channel number is The cooling channel 120 is oriented in the direction of the cooling channel. Represents the coordinate domain position along the cooling channel direction. With the center of the warming zone The distance between them.

[0071] When there are at least two cooling channels 120, and there exists a unique set of two different cooling channels 120 that minimizes the sum of the closest distances between the cooling channels, the controller 150 selects this set of two different cooling channels 120 as the target cooling channels. By selecting the target cooling channels by the sum of the closest distances between the cooling channels, the two target cooling channels can correspond spatially with the connected heating zone, thus facilitating the subsequent determination of the clamping relationship between the two hot zones.

[0072]

[0073] In the formula, The serial number of the connected heating zone is indicated as follows: The number of the first cooling channel corresponding to the connected heating zone. This indicates the number of the second cooling channel corresponding to the connected heating zone. and These represent the closest points of the cooling channels corresponding to the two different cooling channels 120. The selection result is a set of two different cooling channels 120, and this set of two different cooling channels 120 is used as the target cooling channel.

[0074] After selecting two different cooling channels 120 as target cooling channels, the controller 150 determines whether the connecting line segment between the nearest points of the two cooling channels intersects with the corresponding connected heating zone, and determines whether the two directions from the center of the heating zone to the nearest points of the two cooling channels form obtuse angles. An obtuse angle can be represented by the dot product of the two vectors being less than zero. These two conditions are used together to determine the clamping relationship between the two cooling zones.

[0075]

[0076] In the formula, The serial number of the connected heating zone is indicated as follows: The clamping relationship between the two-channel hot zones corresponding to the connected heating zone. This indicates that the clamping relationship between the two hot zones is valid. This represents the line segment connecting the closest points of two cooling channels. Indicates the intersection relationship. Represents the empty set. This indicates that both conditions are true simultaneously. This indicates that two directions pointing from the center of the heating zone to the nearest points of the two cooling channels form obtuse angles.

[0077] When the connecting line segment between the two nearest points of the two cooling channels intersects the connected heating zone, and forms obtuse angles in two directions from the center of the heating zone to the two nearest points of the two cooling channels, the controller 150 obtains the standard point temperature corresponding to the temperature measuring point 110 within the connected heating zone. The temperature measuring point 110 within the connected heating zone is the temperature measuring point whose position falls within the connected heating zone.

[0078] When the temperature at the next point of at least one temperature measuring point 110 within the connected heating zone is higher than the corresponding standard temperature, the cooling channel control result forming unit 180 forms a cooling channel control result for connecting the cooling medium to the two target cooling channels respectively. This cooling channel control result acts on the two target cooling channels respectively, causing the two connecting control elements 140 or the two control outputs of the same connecting control element 140 to allow the cooling medium to enter the two target cooling channels.

[0079] When there are temperature measuring points 110 within the connected heating zone and the next temperature of all temperature measuring points 110 is not higher than the corresponding standard temperature, the cooling channel control result forming unit 180 forms a cooling channel control result for disconnecting or keeping the cooling medium disconnected from the two target cooling channels respectively. This cooling channel control result also applies to the two target cooling channels, ensuring that the connection state between the cooling medium and the two target cooling channels is executed according to the cooling channel control result.

[0080] By using the dual-channel hot zone clamping relationship, the heating zone, the center of the heating zone, the nearest point of the cooling channel, and the distance to the nearest point of the cooling channel are all involved in determining the target cooling channel. The cooling channel control result is still based on the next point temperature, and the standard point temperature is only used as a comparison object to see if the next point temperature is higher than the process reference.

[0081] After the controller 150 generates a cooling channel control result, it outputs a corresponding control signal to the connectivity control unit 140. The connectivity control unit 140 executes the cooling channel control result, causing the connectivity state between the cooling medium and the target cooling channel to change or remain unchanged according to the cooling channel control result. For cooling channel control results used to connect the cooling medium and the target cooling channel, after execution, a connectivity state is formed between the cooling medium supply unit 130 and the target cooling channel.

[0082] For cooling channel control results used to disconnect or maintain the disconnection between the cooling medium and the target cooling channel, execution results in either a disconnected state or a maintained disconnected state between the cooling medium and the target cooling channel. For cooling channel control results used to maintain the connection state, execution results in no change to the connection state between the cooling medium and the target cooling channel.

[0083] In a continuous die-casting production process, after the next sampling time, the controller 150 can reacquire the temperature of the temperature measuring point 110, update the temperature timing sequence, and repeat the next temperature prediction, cooling channel control result formation, and execution. This repetitive process enables the aluminum alloy die-casting mold 100 to form cooling channel control results in advance based on the temperature change trend during multiple sampling times. Each repetition maintains the same control logic: the temperature formation timing sequence characterizes the temperature change trend, the temperature change trend is used to predict the next temperature, and the next temperature is used to form and execute the cooling channel control result.

[0084] The connectivity status after execution can be recorded by the controller 150 so that the cooling channel control result forming unit 180 can identify whether the target cooling channel is in a connected or disconnected state when forming the cooling channel control result in the next cycle. This record does not change the causal relationship between the next temperature point and the cooling channel control result; it is only used to ensure that the connectivity status after execution is consistent with the cooling channel control result in the next control cycle.

[0085] The following is a complete numerical example to illustrate the flow path of point temperature in this embodiment.

[0086] The aluminum alloy die-casting mold 100 is equipped with six temperature measuring points 110 and three cooling channels 120. The cooling medium supply unit 130 controls the connection between the cooling medium and the three cooling channels 120 through three communication control components 140. The six temperature measuring points 110 are distinguished according to their temperature measuring point numbers, and the three cooling channels 120 are distinguished according to their cooling channel numbers.

[0087] Within the same mold coordinate system, the positions of the six temperature measuring points are as follows: , , , , and The cooling channel directions of the three cooling channels 120 are represented by their corresponding centerline coordinates. The above values ​​are used to illustrate the spatial relationship within the same mold coordinate system. The temperature measurement point positions and cooling channel directions are data registered in the controller 150 after the aluminum alloy die-casting mold 100 has been debugged.

[0088] Sampling times are as follows: Second, Second, Second, Seconds and Seconds, the next sampling time is Seconds. The controller 150 acquires the point temperature of all temperature measurement points 110 at each sampling time and writes the point temperature and sampling time of the same temperature measurement point 110 into the corresponding point temperature window. The temperature measurement point number is used as... Taking temperature measurement point 110 as an example, its five continuous temperature points are as follows: , , , and Celsius.

[0089] The point temperature timing generation unit 160 generates the temperature measurement point sequence number based on the above five consecutive point temperatures. The temperature timing sequence of measurement point 110. The next temperature prediction unit 170 obtains the rate of change of four adjacent temperature segments based on the corresponding temperature at adjacent sampling times. And the time interval between adjacent sampling is In seconds, the rate of temperature change of a segment of adjacent points can be obtained as follows: Celsius per second; by The rate of temperature change of a segment of adjacent points can be obtained as follows: Celsius per second; by The rate of temperature change of a segment of adjacent points can be obtained as follows: Celsius per second; by The rate of temperature change of a segment of adjacent points can be obtained as follows: Celsius per second.

[0090] The next point temperature prediction unit 170 averages the rate of temperature change of the four most recent adjacent points to obtain the average rate of temperature change. Degrees Celsius per second. The sampling time interval used to predict the temperature at the next point is... Seconds, the last temperature point in the temperature point window is The temperature is in degrees Celsius, therefore the temperature measurement point number is... The temperature at measurement point 110 at the next sampling time is... Celsius. The temperature should drop a little. The result is formed before arrival and can be used by the cooling channel control result forming unit 180 to form the cooling channel control result.

[0091] Within the same control cycle, the temperature measurement point number is The five consecutive temperature measurement points at point 110 are: , , , and Celsius, and by following the same process, the next point temperature can be obtained as follows: Temperature in degrees Celsius. Temperature measurement point number is... The five consecutive temperature measurement points at point 110 are: , , , and Celsius, and by following the same process, the next point temperature can be obtained as follows: Celsius.

[0092] The standard point temperature registered in controller 150 is: temperature measurement point number is The standard point temperature corresponding to temperature measurement point 110 is Temperature in degrees Celsius, temperature measurement point number is The standard point temperature corresponding to temperature measurement point 110 is Temperature in degrees Celsius, temperature measurement point number is The standard point temperature corresponding to temperature measurement point 110 is Degrees Celsius. Because the temperature measurement point number is... The temperature measurement point 110 is the next point temperature. Higher than the corresponding standard point temperature The cooling channel control result forming unit 180 is capable of forming a cooling channel control result for connecting the cooling medium to the target cooling channel.

[0093] In the registration of the correspondence, the cooling channel serial number is... The cooling channel 120 and the temperature measuring point number are and Temperature measurement point 110 corresponds to the cooling channel number as follows: The cooling channel 120 and the temperature measuring point number are Temperature measurement point 110 corresponds to the cooling channel number as follows: The cooling channel 120 and the temperature measuring point number are The temperature measurement point 110 corresponds to this. Based on this registration correspondence, the cooling channel control result forming unit 180 assigns the cooling channel number as... The cooling channel 120 is defined as the target cooling channel, and a cooling channel control result is formed that acts on the target cooling channel.

[0094] During spatial processing, the controller 150 triangulates the coordinate domain of the mold cavity wall based on the positions of the six temperature measurement points, and performs linear interpolation on the currently obtained temperature and the next temperature within the triangles formed by the triangulation. The currently obtained temperature forms the current temperature surface, and the next temperature forms the next temperature surface. After comparing the next temperature surface and the current temperature surface, the controller 150 determines the coordinate domain position where the next temperature surface is higher than the current temperature surface as the heating zone.

[0095] In this numerical embodiment, there is a connected heating zone within the heating zone, and the temperature measurement point number covered by this connected heating zone is [number missing]. and The coordinates of the temperature measurement point 110 are determined. The controller 150 determines the center of the heating zone of this connected heating zone as... .

[0096] The controller 150 determines the closest point of each of the three pre-registered cooling channels 120 relative to the connected heating zone, based on the pre-registered cooling channel routes. The cooling channel numbers are as follows: The nearest point of the cooling channel 120 is [distance]. Cooling channel number is The nearest point of the cooling channel 120 is [distance]. Cooling channel number is The nearest point of the cooling channel 120 is [distance]. The cooling channel number is... and The two different cooling channels 120 minimize the sum of the distances between the closest points of the cooling channels, and the two different cooling channels 120 in this group are unique. Therefore, the controller 150 selects the two different cooling channels 120 in this group as the target cooling channels.

[0097] Subsequently, controller 150 determines the cooling channel number as follows: and The connecting line segment between the two nearest points of the two different cooling channels 120 intersects the connected heating zone, and it is determined that the two directions from the center of the heating zone to the two nearest points of the two cooling channels form obtuse angles. When both conditions are met, the clamping relationship of the dual-channel hot zone is established. The controller 150 obtains the standard point temperature corresponding to the temperature measuring point 110 in the connected heating zone, and compares the next point temperature of the temperature measuring point 110 in the connected heating zone with the corresponding standard point temperature.

[0098] Because the temperature measuring point number within this connected heating zone is If the temperature at the next point of the temperature measurement point 110 is higher than the corresponding standard point temperature, the cooling channel control result forming unit 180 forms a control result for the cooling medium to be respectively connected to the cooling channel numbered... and The controller 150 outputs the cooling channel control result to the corresponding connection control element 140. After the connection control element 140 executes, the cooling medium supply unit 130 is connected to the two target cooling channels.

[0099] In the same numerical embodiment, if a temperature measuring point 110 exists within another connected heating zone, and the next point temperature of all temperature measuring points 110 within that connected heating zone is not higher than the corresponding standard point temperature, then the cooling channel control result forming unit 180 forms a cooling channel control result for disconnecting or maintaining the disconnection between the cooling medium and the two target cooling channels corresponding to the connected heating zone. After the cooling channel control result is executed, the connection between the cooling medium and the corresponding target cooling channel is disconnected or maintained.

[0100] Although embodiments of this application have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of this application, and all such modifications and variations fall within the scope defined by the appended claims.

Claims

1. A cooling control method for aluminum alloy die casting based on mold temperature time-series prediction, applied to an aluminum alloy die casting mold, wherein the aluminum alloy die casting mold is provided with temperature measuring points and cooling channels, and the communication state between the cooling medium and the cooling channels can be controlled, characterized in that... The method includes: The point temperature of the temperature measuring point is obtained at multiple sampling times, and the point temperature of the same temperature measuring point is formed into a point temperature time sequence according to the sampling time. The point temperature time sequence is used to characterize the point temperature change trend of the temperature measuring point as the sampling time changes. Based on the temperature change trend, predict the next temperature at the next sampling time. Before forming the cooling channel control result, the temperature measurement point position is pre-registered in the same mold coordinate system. Based on the temperature measurement point position, the coordinate domain where the mold cavity wall is located is triangulated. Linear interpolation is performed on the currently obtained point temperature and the next point temperature in the triangle formed by the triangulation to form the current temperature surface and the next temperature surface. The coordinate domain position of the next temperature surface that is higher than the current temperature surface is determined as the heating zone used to participate in determining the target cooling channel. After determining the heating zone, the non-connected parts of the heating zone are respectively determined as the connected heating zones used to determine the target cooling channel; Based on the cooling channel control result of the next point temperature formation acting on at least one of the cooling channels, and the cooling channel acting on the cooling channel control result is determined as the target cooling channel, the cooling channel control result is used to indicate whether the communication state between the cooling medium and the target cooling channel changes or remains before the next sampling time; The cooling channel control result is executed to change or maintain the connection state between the cooling medium and the target cooling channel according to the cooling channel control result.

2. The method for cooling control of aluminum alloy die casting based on mold temperature time-series prediction according to claim 1, characterized in that, Based on the cooling channel control result corresponding to the target cooling channel formed at the next temperature point, including: Obtain a standard point temperature corresponding to the temperature measurement point. When the next point temperature is higher than the standard point temperature, form a cooling channel control result for connecting the cooling medium with the target cooling channel. When the next point temperature is not higher than the standard point temperature, form a cooling channel control result for disconnecting or keeping the cooling medium disconnected from the target cooling channel.

3. The method for cooling control of aluminum alloy die casting based on mold temperature time-series prediction according to claim 1, characterized in that, Determining the target cooling channel includes: A registration correspondence is pre-established, which is used to record the correspondence between each cooling channel and one or more temperature measuring points, and the target cooling channel is determined according to the registration correspondence.

4. The aluminum alloy die-casting cooling control method based on mold temperature time-series prediction according to claim 1, characterized in that, The formation of the point temperature timing sequence includes: At each sampling time, the point temperature of all the temperature measurement points is obtained, and the point temperature of the same temperature measurement point and the sampling time are written into the corresponding point temperature window, and the point temperature window retains multiple consecutive point temperatures arranged according to the sampling time.

5. The method for cooling control of aluminum alloy die casting based on mold temperature time-series prediction according to claim 4, characterized in that, Predicting the next point temperature includes: When five consecutive point temperatures are stored in the point temperature window, the rate of change of adjacent point temperatures is obtained according to the point temperatures corresponding to adjacent sampling times, the average rate of change of point temperatures is obtained according to the rate of change of adjacent point temperatures of the most recent four segments, and the next point temperature is predicted according to the last point temperature in the point temperature window and the average rate of change of point temperatures.

6. The method for cooling control of aluminum alloy die casting based on mold temperature time-series prediction according to claim 1, characterized in that, Determining the target cooling channel based on the connected heating zone includes: The cooling channel routing of each of the aforementioned cooling channels is pre-registered; Determine the center of the heating zone of the connected heating zone, determine the nearest point of the cooling channel to the center of the heating zone on each cooling channel route, and determine the distance from the nearest point of the cooling channel to the nearest point of the cooling channel to the center of the heating zone. When there are at least two cooling channels and there exists a unique set of two different cooling channels that minimizes the sum of the closest distances between the cooling channels, the set of two different cooling channels is selected as the target cooling channel.

7. The method for cooling control of aluminum alloy die casting based on mold temperature time-series prediction according to claim 6, characterized in that, The cooling channel control results include: When the connecting line segment between the two nearest points of the two cooling channels intersects the connected heating zone, and forms an obtuse angle from the center of the heating zone to the two nearest points of the two cooling channels respectively, the standard point temperature corresponding to the temperature measuring point in the connected heating zone is obtained. When the temperature at the next point of at least one of the temperature measuring points in the connected heating zone is higher than the corresponding standard temperature, a cooling channel control result is formed to connect the cooling medium to the two target cooling channels respectively. When the temperature measuring point exists within the connected heating zone and the next point temperature of all the temperature measuring points is not higher than the corresponding standard point temperature, a cooling channel control result is formed to disconnect or keep disconnected the cooling medium from the two target cooling channels respectively.

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