Temperature control and pressure relief method for sprue of low-pressure casting mold and low-pressure casting mold

Abstract

The invention relates to the technical field of low-pressure casting, in particular to a temperature control pressure relief method for a sprue of a low-pressure casting mold and the low-pressure casting mold, which comprises the following steps: responding to a trigger signal, and acquiring product parameters of a standard finished product according to the trigger signal; mold filling pressure and reference temperature are determined according to the product parameters; collecting a preset real-time pressure on the inner side of the sealed crucible; when the real-time pressure is consistent with the mold filling pressure, tamping parameters are determined according to the product parameters; on the basis of the tamping parameters, a perforated push plate preset in a riser tube is controlled to move up and down in a reciprocating mode, and a cooling signal is sent out after movement is finished; in response to the cooling signal, the molten metal extruded into the cavity under pressure is gradually cooled from top to bottom with a preset cooling method, and the preset judgment temperature of a sprue ring is collected in real time; when it is judged that the temperature is consistent with the reference temperature, the compressed gas is controlled to be discharged out of the sealed crucible at a constant speed through a preset pressure relief method. The method has the effect of improving the accuracy of pressure relief opportunity control.

Description

Technical Field

[0001] This invention relates to the field of low-pressure casting technology, and in particular to a method for temperature control and pressure relief at the gate of a low-pressure casting mold and the low-pressure casting mold itself. Background Technology

[0002] Low-pressure casting, as an efficient process for forming light alloy castings, is widely used in the production of high-precision castings such as automotive parts and aerospace structural components due to its advantages such as stable molten metal filling, high casting density, and good forming quality.

[0003] Existing technology involves introducing compressed gas into a sealed crucible, using the gas pressure to slowly press molten metal into the mold cavity along the riser pipe and gate, and then releasing the pressure after the molten metal solidifies to complete the molding process. However, the timing of pressure release currently relies mostly on a preset fixed pressure holding time or the operator's experience.

[0004] However, this pressure relief method is not precise enough when the casting type or the composition of the molten metal changes. It is easy to cause premature pressure relief, resulting in the casting not being completely solidified, or premature pressure relief, resulting in excessive solidification of the molten metal at the gate. Summary of the Invention

[0005] To improve the accuracy of pressure relief timing control, this invention provides a temperature-controlled pressure relief method at the gate of a low-pressure casting mold and the low-pressure casting mold itself.

[0006] In a first aspect, the present invention provides a temperature-controlled pressure relief method at the gate of a low-pressure casting mold, which adopts the following technical solution: A method for temperature-controlled pressure relief at the gate of a low-pressure casting mold, comprising: Step 1: In response to the trigger signal, obtain the product parameters of the standard finished product based on the trigger signal; Step 2: Determine the filling pressure and reference temperature based on the product parameters; Step 5: Collect the real-time pressure inside the pre-set sealed crucible; Step 6: When the real-time pressure and the filling pressure are consistent, determine the compaction parameters according to the product parameters; Step 7: Based on the compaction parameters, control the perforated push plate preset in the riser pipe to move up and down reciprocally, and send a cooling signal after the movement is completed; Step 8: In response to the cooling signal, the molten metal extruded into the mold cavity is gradually cooled from top to bottom using a preset cooling method, and the preset judgment temperature at the gate ring is collected in real time. Step 9: When the temperature is consistent with the reference temperature, the compressed gas is discharged from the sealed crucible at a uniform speed using a preset pressure relief method.

[0007] By adopting the above technical solution, the filling pressure and reference temperature are accurately matched based on product parameters, and the real-time judgment temperature at the gate ring is used as the pressure relief trigger condition. This avoids unstable molten metal backflow and defects such as porosity in the product caused by premature or late pressure relief, thus improving the accuracy of pressure relief timing control.

[0008] Optionally, the process may include the following between step 2 and step 5: Step 30: Obtain the filling image information of the filling block in the preset filling area and the edge image information of the edge block in the preset edge area; read the cavity parameters from the product parameters; and determine the filling features based on the cavity parameters. Step 31: When the image information contains filling features, load the material and output the filling receipt information; Step 32: When the filling image information does not contain filling features, determine the decomposition path based on the comparison relationship between the edge material image information and the filling features; Step 33: Decompose and load materials according to the decomposition path and output edge material receipt information to synchronously update edge material image information, or replenish materials using a preset replenishment method.

[0009] By adopting the above technical solution, the filling characteristics are dynamically determined based on the cavity parameters. The cutting block is cut according to the filling characteristics and placed in the cavity before filling. The cutting block is made of the same material as the product to accelerate the cooling process of the product and improve production efficiency. At the same time, the utilization of the edge material blocks also reduces production costs.

[0010] Optional supplementary methods include: Step 330: Acquire detection image information of cropping blocks in the preset cropping area; Step 3310: When the detected image information does not cover the filling feature, define the clipping block as an edge block and control the edge block to be added to the edge area; Step 33110: When the image information detects the overlay and filling features, determine the cutting path based on the filling contour and cut and separate to obtain the filling block and the edge block; Step 33111: Control the filling block to replenish the filling area, and control the edge material block to replenish the edge material area.

[0011] By adopting the above technical solution, the detection image information of the cutting blocks in the cutting area is first collected, the cutting path is planned, and the filling blocks and edge material blocks that meet the cavity requirements are separated and added to the corresponding areas to realize the replenishment of filling blocks and edge material blocks.

[0012] Optionally, the process may include the following after step 30: Step 340: Determine the filling volume based on the filling receipt information or edge material receipt information, and read the product density and specific heat capacity from the product parameters; Step 341: Calculate the fill mass based on the fill volume and product density; Step 342: Calculate the total volume of the molten metal based on the cavity parameters and filling volume, and read the molten metal density and specific heat capacity from the product parameters; Step 343: Calculate the mass of the molten metal based on the total volume and density of the molten metal; Step 344: Collect the ambient temperature of the cavity and the initial temperature of the filling block or edge material block, and determine the correction coefficient based on the cavity parameters; Step 345: Substitute the product specific heat capacity, filling mass, molten metal specific heat capacity, molten metal mass, ambient temperature, initial temperature, correction coefficient, and reference temperature into the preset thermal balance correction model calculation formula to calculate and determine the new reference temperature, thereby completing the correction of the reference temperature.

[0013] By adopting the above technical solution, combined with the thermal balance correction model, and taking into account multiple factors such as ambient temperature and initial material state, the reference temperature is dynamically corrected to avoid the pre-placed filler blocks or edge blocks from affecting the reference temperature and further affecting the timing of pressure relief.

[0014] Optionally, cooling methods include: Step 80: Determine the cavity height, cooling rate, and initial temperature value based on the cavity parameters; Step 81: Divide the cavity height according to a preset dividing distance to obtain a set of dividing heights, which includes several different dividing height values; Step 82: Determine the volume of liquid metal corresponding to the segmentation height value based on the segmentation height value and the cavity parameters, and determine the heat parameters based on the volume of liquid metal and the specific heat capacity of liquid metal; Step 83: Obtain the simulated temperature value corresponding to the segmentation height value based on the heat parameters and cooling rate, calculate the difference between the simulated temperature value and the initial temperature value, and define it as the heating parameter; Step 84: Determine the total voltage value based on the heating parameters and cooling coefficient, and calculate the mapping relationship between the total voltage value and the preset contact point voltage value to determine the number of contact points; Step 85: In response to the cooling signal, the mold is energized and heated at the cavity position corresponding to the segmentation height value according to the number of contact points, and then the preset cooling water is controlled to flow through the preset cooling water channel to cool the mold.

[0015] By adopting the above technical solution, the cavity is hypothetically segmented, and heating parameters are matched according to different segment height values. Through heating compensation combined with cooling water, the molten metal in the irregular cavity is uniformly cooled from top to bottom, thereby improving the feasibility of using the determined temperature as the pressure relief trigger condition.

[0016] Optionally, the cooling method also includes: Step 86: Determine the water cooling rate based on the preset cooling water temperature and cooling water flow rate, and correct the water cooling rate based on the simulated temperature value; Step 87: Read the volume shrinkage rate from the product parameters, and calculate and determine the filling liquid volume based on the volume shrinkage rate and the volume of molten metal; Step 88: Determine the filling rate based on the filling liquid volume and the corrected water cooling rate; Step 89: Determine the inflation rate based on the filling rate, and control the continuous inflation of compressed gas into the sealed crucible based on the inflation rate.

[0017] By adopting the above technical solution, the shrinkage volume of the cavity area corresponding to different segmentation height values ​​during cooling is matched based on the corrected water cooling rate and volume shrinkage rate, thereby determining the volume of molten metal that needs to be added at each stage. Finally, the gaps in the cavity are filled by the compression of the molten metal by compressed gas, so as to avoid the molten metal shrinking during cooling and causing the generated product to have cavities.

[0018] Optionally, the process may include the following between step 2 and step 5: Step 40: In response to the stirring information, collect the liquid level height and the position of the preset detection point in the stirring rod; Step 41: Determine the tilt angle of the stirring rod based on the liquid level, and determine the circumferential path based on the tilt angle. The circumferential path includes the upper circumferential path and the lower circumferential path. Step 42: Determine the adsorption position based on the detection point location, and determine the adsorption path based on the adsorption position, the preset permanent magnet position, and the surrounding path; Step 43: Control the two permanent magnets preset on the outside of the crucible to move along the adsorption path to the adsorption position, and then move to the upper and lower encircling paths respectively; Step 44: Control the permanent magnet to move continuously along the surrounding path to drive the stirring rod to agitate the molten metal.

[0019] By adopting the above technical solution, a permanent magnet drives a stirring rod to move along a planned up-and-down circular path that is adapted to the liquid level, thereby achieving uniform stirring of the upper and lower layers of the molten metal, reducing component segregation and bubble residue, and improving the purity of the molten metal.

[0020] Optionally, step 44 may include: Step 45: Determine the liquid level rise / fall parameters and ventilation parameters based on the preset pressure rise rate and pressure fall rate; Step 46: Determine the scraping path based on the liquid level height and liquid level rise / fall parameters; Step 47: Based on the ventilation parameters, control the compressed gas to enter and exit the sealed crucible, and control the permanent magnet to move from the surrounding path to the scraping path, and continue to move to drive the stirring rod to scrape off the oxide film and bubbles on the liquid surface, and stop running after a preset time and start to stand to complete the pre-filling preparation.

[0021] By adopting the above technical solution, the molten metal is steadily raised and lowered based on the ventilation parameters. The oxide film and air bubbles on the liquid surface are scraped off with the stirring rod. The molten metal is pretreated before filling the mold to avoid oxidized impurities and air bubbles from being rolled into the mold cavity, thereby further improving the surface quality and internal integrity of the casting.

[0022] Optional depressurization methods include: Step 90: In response to the pressure relief signal, read the molten metal flow rate from the product parameters and obtain the riser diameter; Step 91: Determine the initial velocity based on the fluidity of the molten metal and the diameter of the riser tube; Step 92: Determine the valve opening angle based on the initial rate, control the valve to open based on the valve opening angle to start depressurization, and collect real-time pressure; Step 93: Match the pressure relief path based on real-time pressure; Step 94: Control the corresponding valve to open according to the pressure relief path to switch paths.

[0023] By adopting the above technical solution, the pressure relief rate is dynamically adjusted according to the fluidity of the molten metal and the diameter of the riser pipe. Combined with the preset main and auxiliary multi-stage pressure relief channels and multi-path switching, uniform pressure relief is achieved, ensuring that the molten metal in the riser pipe flows back smoothly.

[0024] Secondly, this application provides a low-pressure casting mold, which adopts the following technical solution: A low-pressure casting mold, controlled by the temperature control and pressure relief method at the gate of a low-pressure casting mold as described above, includes a casting structure with a cavity and a temperature measuring structure with a temperature measuring rod. A gate is provided at one end of the cavity. The temperature measuring rod is installed inside the casting structure and is used to detect the temperature at the gate. The temperature measuring structure also includes a heat-conducting ring installed outside the gate ring. The heat-conducting ring is used to reduce the interference of local fluctuations on the temperature measurement. The detection end of the temperature measuring rod abuts against the outside of the heat-conducting ring.

[0025] By adopting the above technical solution, the heat-conducting ring made of high thermal conductivity metal increases the contact area with the gate ring and suppresses local temperature fluctuations, thereby improving the accuracy and stability of the temperature measuring rod in detecting the temperature at the gate.

[0026] In summary, the present invention has at least one of the following beneficial technical effects: 1. Based on the precise matching of filling pressure and reference temperature according to product parameters, the real-time judgment temperature at the gate ring is used as the pressure relief trigger condition to avoid unstable molten metal backflow and defects such as porosity in the product caused by too early or too late pressure relief, thus improving the accuracy of pressure relief timing control. 2. The cavity is hypothetically segmented, and heating parameters are matched according to different segment height values. Through heating compensation combined with cooling water, the molten metal in the irregular cavity is uniformly cooled from top to bottom, thereby improving the feasibility of using the determined temperature as the pressure relief trigger condition. 3. The use of a heat-conducting ring made of high thermal conductivity metal increases the contact area with the gate ring and suppresses local temperature fluctuations, thereby improving the accuracy and stability of the temperature measurement rod at the gate. Attached Figure Description

[0027] Figure 1 This is a structural schematic diagram of a low-pressure casting mold according to this application; Figure 2 This is a cross-sectional view of a low-pressure casting mold according to this application; Figure 3 yes Figure 2 Enlarged view of point A in the middle; Figure 4 This is a flowchart of a method for temperature control and pressure relief at the gate of a low-pressure casting mold according to this application; Figure 5 This is a flowchart of the cooling method of this application; Figure 6 This is a simplified diagram illustrating the use of the stirring rod in this application.

[0028] The parts referred to by the numbers in the above attached diagrams are as follows: 1. Casting structure; 11. Mold cavity; 12. Sprue ring; 2. Temperature measuring structure; 21. Heat conducting ring; 22. Temperature measuring rod; 3. Sealed crucible; 4. Lifting pipe; 5. Stirring rod; 6. Permanent magnet; 7. Circulating path. Detailed Implementation

[0029] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0030] This invention discloses a low-pressure casting mold.

[0031] Reference Figure 1 and Figure 2 A low-pressure casting mold includes a casting structure 1 with a cavity 11 and a temperature measuring structure 2.

[0032] Reference Figure 2 and Figure 3The casting structure 1 has a gate for injecting molten metal at the bottom of the cavity 11. The casting structure 1 includes a gate ring 12, which is sealed and snapped at the gate of the cavity 11 and is used to guide the molten metal to flow into the cavity 11. The gate ring 12 facilitates the temperature detection at the gate by the temperature measuring structure 2.

[0033] The temperature measuring structure 2 includes a heat-conducting ring 21 and a temperature measuring rod 22.

[0034] A heat-conducting ring 21 is fixedly snapped onto the outside of the gating ring 12. The heat-conducting ring 21 is used to increase the contact area with the gating ring 12 and reduce thermal resistance. A temperature measuring rod 22 is fixedly installed on the inside of the casting structure 1, and the sensing end of the temperature measuring rod 22 abuts against the outside of the heat-conducting ring 21.

[0035] In this embodiment, the heat-conducting ring 21 is made of a high thermal conductivity metal with a semi-circular cross-section, such as a nickel-based high-temperature alloy. A groove is provided on the outer side of the gating ring 12 for engaging and fixing the heat-conducting ring 21. The temperature measuring rod 22 is an electronic temperature measuring rod, which is existing technology and will not be described in detail here.

[0036] In use, the casting structure 1 is assembled above the sealed crucible 3, and the sealed crucible 3 is sealed and connected to the gate of the casting structure 1 through the riser pipe 4. Molten metal is poured into the sealed crucible 3, and then compressed gas is introduced into the sealed crucible 3. The compressed gas compresses the molten metal, causing it to flow from the riser pipe 4 and fill the cavity 11. The molten metal gradually cools from top to bottom. After the molten metal in the cavity 11 has completely cooled, the sealed crucible 3 is connected to the outside world so that excess compressed gas can be discharged from the sealed crucible 3. Without the compression of the compressed gas, the unsolidified molten metal in the riser pipe 4 and at the gate flows back to the sealed crucible 3. The cooled metal in the cavity 11 is then removed to complete the low-pressure casting.

[0037] Based on the same inventive concept, embodiments of the present invention provide a method for temperature control and pressure relief at the gate of a low-pressure casting mold.

[0038] refer to Figure 4 A method for temperature-controlled pressure relief at the gate of a low-pressure casting mold, comprising the following steps: Step 1: In response to the trigger signal, obtain the product parameters of the standard finished product based on the trigger signal.

[0039] A trigger signal is a command signal that initiates the temperature control and pressure relief process. It can be output through equipment operation commands or manual operation commands. Specifically, it can refer to the operator clicking the start button on the control panel, which is the start switch for the entire process.

[0040] Product parameters refer to the core technical data set of a standard finished product, including key information such as product size, material, weight, and molding requirements. Staff members search for and match the corresponding parameter set by product model and import it into the system in advance.

[0041] Step 2: Determine the filling pressure and reference temperature based on the product parameters.

[0042] The filling pressure refers to the compressed gas pressure required to completely fill the mold cavity 11 with molten metal. Parameters such as the cavity volume, gate cross-sectional area, and molten metal density are read from the product parameters. The basic value is obtained through fluid dynamics simulation calculation, and then corrected by combining the production experience data of similar products to determine the final filling pressure.

[0043] The reference temperature refers to the temperature threshold used to determine whether the molten metal at the gate has reached the pressure relief condition based on standard finished product parameters. The solidification temperature threshold of the product is obtained from the product parameters, and the corresponding reference temperature is found in the temperature correspondence table based on the solidification temperature threshold. The temperature correspondence table is a data table that records different solidification temperature thresholds and their corresponding reference temperatures. It is obtained by technicians through prior testing and will not be elaborated here.

[0044] According to the product, the corresponding molten metal is injected into the sealed crucible 3 below the mold. The sealed crucible 3 continuously heats the molten metal to keep it at a constant temperature. A riser pipe 4 is provided between the sealed crucible 3 and the mold to guide the molten metal from the gate below the mold into the cavity 11.

[0045] Step 5: Collect the real-time pressure inside the preset sealed crucible 3.

[0046] Real-time pressure refers to the current gas pressure value inside the sealed crucible 3, which is acquired in real time by an interferometric pressure sensor that is pre-fixed inside the sealed crucible 3. The interferometric pressure sensor can withstand the high temperature and high pressure environment in the sealed crucible 3, which is the existing technology.

[0047] Compressed gas is introduced into the sealed crucible 3, and the compressed gas applies pressure to the surface of the molten metal to force the molten metal from the riser pipe 4 into the cavity 11 of the mold.

[0048] Step 6: When the real-time pressure and the filling pressure are consistent, determine the compaction parameters according to the product parameters.

[0049] The consistency between the real-time pressure and the filling pressure indicates that the pressure of the compressed gas inside the sealed crucible 3 has reached the filling pressure standard. Under the action of pressure, the molten metal has completely flowed into and filled the cavity 11, and the filling stage is completed. At this time, the filling of compressed gas is stopped, and the sealed crucible 3 maintains constant temperature heating of the molten metal.

[0050] The compaction parameters refer to the core parameters that control the perforated push plate inside the riser pipe 4 to move up and down reciprocally. These parameters include the stroke, frequency, pressure, and duration. The compaction parameters are determined by first reading parameters such as the cavity depth, cavity structure, and molten metal flowability from the product parameters and then simulating the molten metal compaction process using finite element simulation.

[0051] Step 7: Based on the compaction parameters, the perforated push plate in the riser pipe 4 is controlled to move up and down reciprocally, and a cooling signal is issued after the movement is completed.

[0052] The cooling signal is a command signal issued after the perforated push plate moves up and down to compact the molten metal, which initiates the molten metal cooling process. It is generated by the system based on the execution status of the compaction parameters.

[0053] The perforated pusher plate is a plate-shaped component pre-installed inside the riser tube 4. It has several through holes that do not affect the flow of molten metal and has high temperature resistance and corrosion resistance. It is designed and installed in advance according to the inner diameter of the riser tube 4, the temperature of the molten metal and the compaction pressure requirements. In this embodiment, it can be made of Inconel alloy.

[0054] After the molten metal fills the cavity 11, the perforated push plate is controlled to move up and down reciprocally based on the compaction parameters. When the perforated push plate moves upward, the speed is greater than when it moves downward. The slower speed causes the molten metal to flow upward from below the perforated push plate along the through hole, while the faster speed causes the molten metal to be squeezed upward by force, thereby eliminating the air holes in the molten metal in the cavity 11 and completing the compaction action.

[0055] Step 8: In response to the cooling signal, the molten metal extruded into the cavity 11 under pressure is gradually cooled from top to bottom using a preset cooling method, and the preset judgment temperature at the gate ring 12 is collected in real time.

[0056] The cooling method refers to the specific way of cooling the molten metal from top to bottom in a gradient. It is set in advance by the staff and stored in the system. The specific method will be described in subsequent steps and will not be repeated here.

[0057] The determination temperature refers to the temperature value at the gate ring 12, which is used to determine whether the cooling state of the molten metal has reached the pressure relief requirement. It is obtained in real time through the temperature measuring structure 2.

[0058] The molten metal in the cavity 11 gradually cools and solidifies from top to bottom. By collecting the temperature at the gate ring 12 and comparing it with the reference temperature, it can be determined whether the molten metal in the cavity 11 has finished cooling.

[0059] Step 9: When the temperature is determined to be consistent with the reference temperature, the compressed gas is controlled to be discharged from the sealed crucible 3 at a uniform speed using a preset pressure relief method.

[0060] The fact that the temperature is consistent with the reference temperature indicates that the temperature of the molten metal at the gate ring 12 has cooled to the reference temperature, and the molten metal in the cavity 11 has completed the main solidification process, meeting the conditions for molten metal to flow back after pressure relief.

[0061] The pressure relief method refers to the specific way of controlling the compressed gas in the sealed crucible 3 to be discharged at a uniform speed, so as to restore the gas pressure in the sealed crucible 3 to the normal value, and then allow the molten metal in the riser pipe 4 to flow back to the sealed crucible 3. The specific method will be described in the following steps and will not be repeated here.

[0062] Once the molten metal in cavity 11 has basically cooled down, the gas in the sealed crucible 3 is discharged to complete the pressure relief, allowing the excess molten metal to flow back.

[0063] The following steps are also included between step 2 and step 5: Step 30: Obtain the filling image information of the filling block in the preset filling area and the edge image information of the edge block in the preset edge area, read the cavity parameters from the product parameters, and determine the filling features based on the cavity parameters.

[0064] The filling area refers to the specific area used to place the filling blocks, which facilitates the storage and loading of the filling blocks. The boundary coordinates of the flat area near the mold are collected by the staff and entered into the system.

[0065] The filler block refers to a complete block of material that can be placed directly into the cavity 11 to accelerate the cooling process. It is cut from the cutter block according to the filling characteristics.

[0066] Fill image information refers to image data obtained by photographing the fill area, including visual information such as the number, shape, and position of the fill blocks. It is obtained by taking pictures with an industrial camera that is pre-fixed above the fill area.

[0067] The edge material area refers to a specific area used to place edge material blocks, which facilitates the storage and loading of edge material blocks. The boundary coordinates of the flat area near the mold are collected by the staff and entered into the system.

[0068] Edge material refers to block-shaped material that does not yet meet the filling characteristics and needs to be processed through decomposition, cutting and other processes before it can be placed in cavity 11. It is either the whole cut block that does not meet the filling characteristics or the edge material left after the cut block is cut.

[0069] Edge material image information refers to image data obtained by photographing the edge material area, including visual information such as the quantity, shape, and position of edge material blocks. It is obtained by taking pictures with an industrial camera that is pre-fixed above the edge material area.

[0070] The filling feature refers to the cutting standard of the filling block and the reference feature when identifying the filling block. The cavity parameters are read from the product parameters, and then the size boundary features that can be placed in the cavity 11 are determined according to the cavity parameters, which are the filling features.

[0071] Step 31: When the image information contains filling features, load the material and output the filling receipt information.

[0072] The presence of filling features in the filling image information indicates the existence of a filling block within the filling area. Based on the coordinate position of the filling block and the coordinate position of the cavity 11, the robot arm is controlled to clamp and move the filling block into the cavity 11.

[0073] The presence of fill features in the filled image information indicates the existence of fill blocks within the fill area that can be directly filled. The system uses the Canny operator algorithm to match the filled image information with the fill features. When the matching degree reaches 95%, it is determined that the fill features are present, i.e., a fill block exists.

[0074] Filling receipt information refers to the confirmation signal fed back by the system after the filling block has been loaded. The system generates information containing parameters such as loading time and filling block information based on the signal after the position sensor pre-fixed on the robot arm completes the loading.

[0075] Step 32: When the filling image information does not contain filling features, determine the decomposition path based on the comparison relationship between the edge material image information and the filling features.

[0076] If the filled image information does not contain filling features, it means that there is no filling block in the filled area. The system uses the Canny operator algorithm to match the filled image information with the filling features. When the matching degree does not reach 95%, it is determined that there are no filling features, that is, there is no filling block.

[0077] The decomposition path refers to the specific cutting path planned by decomposing and combining the edge material blocks into a 95% matching degree with the filling features based on the differences between the shape features and filling features of the edge material blocks. The Canny operator algorithm is used to compare the differences between the edge material image information and the filling features, and a greedy algorithm is used to plan the path with the minimum number of cuts, which is the decomposition path.

[0078] If the edge block cannot meet the filling characteristic standard through decomposition and combination, then the decomposition path is empty.

[0079] Step 33: Decompose and load materials according to the decomposition path and output edge material receipt information to synchronously update edge material image information, or replenish materials using a preset replenishment method.

[0080] When a decomposition path exists, the preset cutting equipment is controlled to cut the edge material blocks along the decomposition path, and the robotic arm is controlled to pick up and load the materials sequentially. When the decomposition path is empty, the material is replenished using a preset replenishment method.

[0081] Edge material feedback information refers to the confirmation signal fed back by the system after the edge material block has been decomposed and fed according to the decomposition path. The system generates information containing parameters such as feeding time and edge material block information based on the signal after the feeding is completed by the position sensor that is pre-fixed and installed on the robot arm.

[0082] The supplementary method refers to the specific process used to supplement qualified filler blocks when there are no filler blocks and the edge material blocks cannot meet the demand after decomposition. The process is set in advance by the staff and stored in the system. The specific method will be described in the following steps and will not be elaborated here.

[0083] The supplementary method includes the following steps: Step 330: Collect the detection image information of the cropping blocks in the preset cropping area.

[0084] The cutting area refers to the specific area used for detecting, cutting and separating the cutting blocks. The boundary coordinates of the flat area near the mold are collected by the staff and entered into the system.

[0085] Cutting blocks refer to block-shaped raw materials that are to be filled and cut. Materials of the same material are matched according to the product material in the product parameters for feeding.

[0086] The height of the cut block is fixed. When determining the filling feature, the height of the cut block is compared with the cavity 11 to determine the shape of the cut block that can be accommodated inside the cavity 11. The filling feature is obtained by this comparison. Similarly, when performing operations such as cutting, decomposing and combining, the height is fixed by default. The cutting, decomposing and combining routes are planned on the surface above the cut block.

[0087] The image information to be detected refers to the image data obtained by taking pictures of the cutting area, which includes visual information such as the shape and position of the cutting block. It is obtained by taking pictures with an industrial camera that is pre-fixed and installed above the cutting area.

[0088] Step 3310: When the detected image information does not cover the filling feature, define the cut block as the edge block and control the edge block to be added to the edge area.

[0089] If the image information does not cover the filling feature, it means that the image data of the cut block does not show any area that matches the filling feature. That is, the cut block cannot be cut to obtain a complete filling block, and is directly defined as an edge block. The preset robot arm is controlled to pick up the cut block and move it to the edge area.

[0090] Step 33110: When the image information is detected to contain filling features, the cutting path is determined based on the filling contour and the pieces are cut and separated to obtain the filling block and the edge block.

[0091] The detection of the filling feature in the image information indicates that there is a region in the image data of the cropped block that matches the filling feature, that is, the cropped block can be cropped to obtain a complete filling block.

[0092] The cutting path refers to the specific cutting trajectory that accurately divides the cutting block into filling blocks and edge blocks based on the contour of the filling features in the cutting block. The cutting path is planned and optimized by a genetic algorithm with material utilization rate as the core indicator, so that the size of the edge block after cutting is minimized.

[0093] The preset cutting device is controlled to cut and separate the cutting blocks along the cutting path. The part that meets the filling characteristics is the filling block, and the part that does not meet the filling characteristics is the edge block.

[0094] Step 33111: Control the filling block to replenish the filling area, and control the edge material block to replenish the edge material area.

[0095] The system controls a pre-set robotic arm to pick up filler blocks and move them to the filling area, and to pick up edge material blocks and move them to the edge material area, thereby replenishing the filler blocks. At the same time, excess edge material blocks are also utilized to reduce waste.

[0096] The following steps are included after step 30: Step 340: Determine the filling volume based on the filling receipt information or edge material receipt information, and read the product density and specific heat capacity from the product parameters.

[0097] The filling volume refers to the total volume of material moved into cavity 11. If a filling receipt is detected, it means that a filling block is placed in cavity 11, and the filling volume is the volume of the filling block, which can be directly read from the filling receipt information. If an edge material receipt is detected, it means that an edge material block is placed in cavity 11, and the filling volume is the sum of the volumes of all edge material blocks, which can be calculated by directly reading the volume of a single edge material block from the edge material receipt information and summing them.

[0098] The surface area of ​​the infill block can be identified from the infill features. Combined with the height value of the trimming block, the volume of the infill block can be calculated and recorded in the infill receipt information. Similarly, the surface area of ​​the edge material block to be placed in cavity 11 can be identified from the edge material image information. Combined with the height value of the trimming block, the volume of the edge material block can be calculated and recorded in the edge material receipt information. Since only a 95% matching degree is required when comparing the decomposed and combined edge material blocks with the infill features, the volume of the combined edge material blocks is not completely consistent with the volume of the infill block. Therefore, it needs to be calculated separately to improve accuracy.

[0099] Product density refers to the ratio of the mass to the volume of a standard finished product, which is obtained directly from the product parameters.

[0100] The specific heat capacity of a product refers to the amount of heat absorbed or released by a unit mass of standard finished product when its temperature rises or falls by a unit, which can be directly obtained from the product parameters.

[0101] Step 341: Calculate the fill mass based on the fill volume and product density.

[0102] Filler mass refers to the total weight of the filler material, which is calculated by multiplying the filler volume by the product density.

[0103] Step 342: Calculate the total volume of the molten metal based on the cavity parameters and filling volume, and read the molten metal density and specific heat capacity from the product parameters.

[0104] The total volume of molten metal refers to the total volume of molten metal that needs to be added to cavity 11 after the filling block or edge block has been placed. It is obtained by reading the cavity volume from the cavity parameters and then calculating the difference between the cavity volume and the filling volume.

[0105] The density of molten metal is the ratio of the mass to the volume of molten metal, which can be directly obtained from the product parameters.

[0106] The specific heat capacity of molten metal refers to the amount of heat absorbed or released by a unit mass of molten metal when its temperature rises or falls by a unit, which can be directly obtained from the product parameters.

[0107] Step 343: Calculate the mass of the molten metal based on the total volume and density of the molten metal.

[0108] The mass of molten metal refers to the total mass of molten metal participating in casting in cavity 11, which is calculated by multiplying the total volume of molten metal by the density of molten metal.

[0109] Step 344: Collect the ambient temperature of cavity 11 and the initial temperature of the filling block or edge material block, and determine the correction coefficient based on the cavity parameters.

[0110] Ambient temperature refers to the temperature of the ambient medium surrounding cavity 11, which is obtained in real time by a temperature sensor that is pre-fixed and installed on the outside of the mold.

[0111] The initial temperature refers to the temperature of the filler block or edge material block before it moves into the cavity 11. It is obtained by collecting the surface temperature of the filler block or edge material block before it is loaded by a temperature sensor.

[0112] The correction factor is a coefficient used to correct errors in thermal balance calculations. Its value range is based on the cavity structure and material properties. Data such as cavity surface area and heat dissipation coefficient are read from the cavity parameters, and the staff obtains the value by fitting experimental data and substituting it into the cavity parameters.

[0113] Step 345: Substitute the product specific heat capacity, filling mass, molten metal specific heat capacity, molten metal mass, ambient temperature, initial temperature, correction coefficient, and reference temperature into the preset thermal balance correction model calculation formula to calculate and determine the new reference temperature, thereby completing the correction of the reference temperature.

[0114] The thermal balance correction model calculation formula refers to a mathematical model used to correct the reference temperature. Its core is to calculate the actual temperature threshold for cooling the molten metal to the target state based on the thermal balance principle. A basic formula is derived based on this principle, and then calibrated using data collected from multiple sets of orthogonal experiments. Specifically, it is: T = T0 + (c1m1(T1-T0) + c2m2(T2-T0)) * k / (c2m2), where T is the corrected reference temperature, T0 is the ambient temperature, c1 is the specific heat capacity of the product, m1 is the filling mass, T1 is the initial temperature, c2 is the specific heat capacity of the molten metal, m2 is the mass of the molten metal, T2 is the original reference temperature, and k is the correction coefficient.

[0115] refer to Figure 5 The cooling method includes the following steps: Step 80: Determine the cavity height, cooling rate, and initial temperature value based on the cavity parameters.

[0116] The cavity height refers to the total height of cavity 11 in the vertical direction, which is obtained directly from the cavity parameters.

[0117] Cooling rate refers to the rate at which the temperature of molten metal drops per unit time during the cooling process. It is determined in advance by the staff based on the product material and forming requirements and recorded in the product parameters.

[0118] The initial temperature value refers to the temperature of the molten metal when it enters the mold cavity 11. The staff determines and records this value in the product parameters in advance based on the product material and molding requirements.

[0119] When the molten metal is poured into the sealed crucible 3, the temperature is approximately the same as the initial temperature. Subsequently, the temperature of the molten metal is controlled by the sealed crucible 3 to keep the molten metal at the initial temperature.

[0120] Step 81: Divide the cavity height according to the preset dividing distance to obtain a set of dividing heights, which includes several different dividing height values.

[0121] The segmentation distance refers to the vertical spacing between each cooling segment when segmenting the cavity 11 for cooling. It is determined based on the cavity height to ensure that the cavity 11 is evenly divided and the spacing between each segment is appropriate. For example, first determine that the spacing between each segment is between 15mm and 25mm, then determine the number of segments based on the cavity height. When the cavity height is less than 50mm, it is recommended to divide it into 2 to 3 segments; when the cavity height is between 50mm and 100mm, it is recommended to divide it into 3 to 5 segments.

[0122] The segmented height set refers to the set of all segmented height nodes after dividing the cavity height according to the segmentation distance. For example, if the cavity height is 120mm and the segmentation distance is 20mm, then the set is {20, 40, 60, 80, 100, 120}.

[0123] The segment height value refers to a single height node in the segment height set. Each value corresponds to an independent cooling area of ​​cavity 11. Starting from the bottom of cavity 11, the values ​​increase sequentially upwards according to the segment distance until they reach the value of the height node formed by the cavity height.

[0124] Step 82: Determine the volume of liquid metal corresponding to the segmentation height value based on the segmentation height value and the cavity parameters, and determine the heat parameters based on the volume of liquid metal and the specific heat capacity of liquid metal.

[0125] The liquid metal volume refers to the volume of liquid metal contained in the cooling area of ​​cavity 11 corresponding to the segmentation height value. The liquid metal volume corresponds one-to-one with the segmentation height value. A three-dimensional parameter model is established through the cavity parameters, and then the corresponding multi-segment cavity area is matched according to the segmentation height value. The value of the liquid metal volume is obtained from the three-dimensional parameter model.

[0126] The heat parameter refers to the total heat of the molten metal in the cavity area corresponding to the segment height value. The heat parameter corresponds one-to-one with the volume of the molten metal and is directly proportional to it. The temperature difference is calculated based on the initial temperature and the solidification temperature threshold. Then, the total heat carried by the molten metal as it cools to solidification is calculated by combining the volume of the molten metal and the specific heat capacity of the molten metal.

[0127] Step 83: Obtain the simulated temperature value corresponding to the segmentation height value based on the heat parameters and cooling rate, calculate the difference between the simulated temperature value and the initial temperature value, and define it as the heating parameter.

[0128] The simulated temperature value refers to the real-time temperature of the molten metal in the cavity area corresponding to any segment height value when the temperature of the molten metal in the cavity area corresponding to any segment height value drops to the solidification temperature threshold. The theoretical cooling temperature, i.e. the simulated temperature value, is obtained by inputting heat parameters, cooling rate and thermal conductivity of mold material into thermal conduction simulation software (such as ANSYS).

[0129] Heating parameters refer to the temperature values ​​corresponding to the amount of heat applied to different cavity areas to ensure uniform cooling from top to bottom during the cooling process. These parameters are obtained by calculating the difference between the simulated temperature value and the reference temperature value.

[0130] Since the heat parameters corresponding to each segment height value are different, the cooling efficiency varies under the same cooling rate. Therefore, when the temperature of the molten metal in the cavity area corresponding to any segment height value drops to the solidification temperature threshold, the other molten metals have not yet solidified. It is necessary to heat the cavity positions corresponding to each segment height value using heating parameters to ensure uniform cooling from top to bottom. In this embodiment, the basic heating amount required for all areas to cool simultaneously can be determined first, and then a certain amount of heating can be uniformly increased on top of this to achieve the target effect.

[0131] Step 84: Determine the total voltage value based on the heating parameters and cooling coefficient, and calculate the mapping relationship between the total voltage value and the preset contact point voltage value to determine the number of contact points.

[0132] The total voltage refers to the total heating voltage required for the cavity area corresponding to each segment height value in order to achieve the target heating effect. It is calculated by multiplying the heating parameters and the cooling coefficient.

[0133] The contact point voltage value refers to the rated operating voltage of each heating contact point. The specifications of the heating element are tested by the staff and entered into the system.

[0134] The number of contact points refers to the number of heating contact points required to achieve the total voltage value in the cavity area corresponding to different segmentation heights. It is calculated by dividing the total voltage value by the contact point voltage value and rounding down.

[0135] Since different cavity regions corresponding to different segmentation heights require different heating parameters, the total voltage value is adjusted by changing the number of contact points.

[0136] Step 85: In response to the cooling signal, the mold is energized and heated at the cavity position corresponding to the segmentation height value according to the number of contact points, and then the preset cooling water is controlled to flow through the preset cooling water channel to cool the mold.

[0137] Cooling water refers to a heat transfer medium with good thermal conductivity used for mold cooling; in this embodiment, it is industrial deionized water.

[0138] Cooling channels refer to hollow channels pre-installed inside the casting structure 1 for the flow of cooling water. The channel distribution is adapted to the contour of the cavity 11 to ensure uniform cooling. They are planned and opened according to the cavity structure during mold processing.

[0139] The cooling method also includes the following steps: Step 86: Determine the water cooling rate based on the preset cooling water temperature and cooling water flow rate, and correct the water cooling rate based on the simulated temperature value.

[0140] Water cooling rate refers to the cooling rate of molten metal achieved through cooling water circulation. It is determined by the cooling water temperature and flow rate. First, the cooling coefficient is determined based on the structure of the cooling water channel. Then, the water cooling rate is calculated based on the collected cooling water temperature and flow rate. The calculation formula is: Water cooling rate = Cooling coefficient * (Cooling water temperature - Molten metal temperature) / Cooling water flow rate.

[0141] Step 87: Read the volume shrinkage rate from the product parameters, and calculate and determine the filling liquid volume based on the volume shrinkage rate and the volume of molten metal.

[0142] Volume shrinkage rate refers to the proportion of volume reduction of molten metal during the cooling process from liquid to solid state, which can be directly obtained from product parameters.

[0143] The filling liquid volume refers to the volume of the molten metal used to compensate for the cooling and shrinkage of the molten metal. It is calculated by multiplying the molten metal volume by the volume shrinkage rate.

[0144] Step 88: Determine the filling rate based on the filling liquid volume and the corrected water cooling rate.

[0145] The filling rate refers to the speed at which molten metal enters the cavity 11 through the riser pipe 4. The temperature difference is calculated by subtracting the temperature of the molten metal from the solidification temperature threshold. The cooling and solidification time of the molten metal is calculated based on the temperature difference and the cooling rate. The filling rate is obtained by quotienting the filling volume and the cooling and solidification time.

[0146] Step 89: Determine the inflation rate based on the filling rate, and control the continuous inflation of compressed gas into the sealed crucible 3 based on the inflation rate.

[0147] The inflation rate refers to the speed at which compressed gas is injected into the sealed crucible 3 to fill the voids left by the cooled molten metal in the mold cavity 11. The cross-sectional area of ​​the riser pipe 4 is read from the product parameters. The operator then looks up the corresponding gas pressure correction coefficient from a coefficient correspondence table based on the filling pressure. The inflation rate is calculated by multiplying the filling rate, cross-sectional area, and gas pressure correction coefficient. The coefficient correspondence table records different filling pressures and their corresponding gas pressure correction coefficients; this data was obtained through prior testing by technicians and will not be elaborated upon here.

[0148] refer to Figure 6 Between step 2 and step 5, the following steps are also included: Step 40: In response to the stirring information, collect the liquid level height and the position of the preset detection point in the stirring rod 5.

[0149] Stirring information refers to the instruction signal to start the stirring process of molten metal. The stirring process is triggered by the manual input of the stirring command by the staff.

[0150] The liquid level height refers to the vertical distance between the surface of the molten metal inside the sealed crucible 3 and the bottom of the crucible, which is collected in real time by a liquid level sensor.

[0151] The detection point location refers to the coordinates of the points preset at both ends of the stirring rod 5. This is obtained by setting cavities with marking functions at both ends of the stirring rod 5 and then detecting them using preset infrared sensors.

[0152] The stirring rod 5 is a rod-shaped body that is pre-set and placed inside the sealed crucible 3 for stirring the molten metal. It has high temperature resistance and ferromagnetism, and can move with the permanent magnet 6. It has cavities at both ends for easy infrared detection.

[0153] Step 41: Determine the tilt angle of the stirring rod 5 based on the liquid level, and determine the surrounding path 7 based on the tilt angle. The surrounding path 7 includes an upper surrounding path and a lower surrounding path.

[0154] The tilt angle refers to the tilt angle of the stirring rod 5 relative to the vertical direction, which is determined based on the liquid level. This ensures that the stirring rod 5 can fully contact the molten metal for stirring. The effective length of the stirring rod 5 after tilting is set according to a certain proportion of the liquid level. The tilt angle is then calculated based on the length of the stirring rod 5. The tilt angle = arctan(effective length / liquid level).

[0155] In this embodiment, the ratio is set to 80%, that is, when the liquid level is 100mm, the effective length is 80mm, and when the length of the stirring rod 5 is 100mm, the tilt angle is approximately 53° according to the formula.

[0156] The orbital path 7 refers to the trajectory of the stirring rod 5 driven by the permanent magnet 6 in the molten metal. It is divided into an upper orbital path near the liquid surface and a lower orbital path near the bottom of the sealed crucible 3. The two paths are set on the outside of the sealed crucible 3 based on the length and tilt angle of the stirring rod 5 using the Dijkstra algorithm.

[0157] Step 42: Determine the adsorption position based on the detection point location, and determine the adsorption path based on the adsorption position, the preset permanent magnet position, and the surrounding path 7.

[0158] The adsorption position refers to the specific position where the permanent magnet 6 generates an effective adsorption force on the stirring rod 5. Based on the material of the stirring rod 5 and the magnetic range of the permanent magnet 6, the distance and angle at which the permanent magnet 6 generates an effective adsorption force on the stirring rod 5 are determined experimentally. The adsorption position is the closest point extending outward from the detection point to the sealed crucible 3.

[0159] The position of the permanent magnets refers to the initial installation coordinates of the two permanent magnets 6 on the outside of the crucible, which are obtained by acquiring the position of the permanent magnets 6 through a laser locator.

[0160] The adsorption path refers to the shortest path for the two permanent magnets 6 to move to the nearest adsorption position and then to the upper or lower circumferential path. It is obtained by planning based on the permanent magnet position, adsorption position and circumferential path 7 using the Dijkstra algorithm, while ensuring that the final landing points of the two permanent magnets 6 are located on both sides of the sealed crucible 3 and far away from each other.

[0161] Step 43: Control the two permanent magnets 6 preset on the outside of the crucible to move along the adsorption path to the adsorption position, and then move to the upper and lower surrounding paths respectively.

[0162] The robotic arm controls two permanent magnets 6 to move to the adsorption position according to the adsorption path. The two ends of the stirring rod 5 are adsorbed and controlled by the two permanent magnets 6 respectively. The permanent magnets 6 then move to the surrounding path 7. The stirring rod 5 follows the permanent magnets 6 to complete the tilt angle setting. It presents an up-and-down tilted posture in the sealed crucible 3 and is immersed in the molten metal.

[0163] Step 44: Control the permanent magnet 6 to move continuously along the surrounding path 7 to drive the stirring rod 5 to stir the molten metal.

[0164] Two permanent magnets 6 are controlled by a robotic arm to rotate along the surrounding path 7, and the stirring rod 5 follows the rotation of the permanent magnets 6 to stir the molten metal.

[0165] The following steps are included after step 44: Step 45: Determine the liquid level rise / fall parameters and ventilation parameters based on the preset pressure rise rate and pressure fall rate.

[0166] The pressure increase rate and pressure decrease rate refer to the pressure rise or fall per unit time when compressed gas is filled into or discharged from the sealed crucible 3. They are determined according to the fluidity and viscosity of the molten metal. For molten metal with good fluidity, the pressure increase rate can be set to 0.05 to 0.1 MPa / min and the pressure decrease rate can be set to 0.03 to 0.08 MPa / min; for molten metal with poor fluidity, the rate should be appropriately reduced.

[0167] The liquid level rise and fall parameters refer to the speed and amplitude of the rise or fall of the liquid level in the sealed crucible 3 when compressed gas is filled or discharged based on the pressurization rate and depressurization rate. The cross-sectional area of ​​the riser pipe 4 is collected and then calculated based on the formula. The specific calculation formula is: Liquid level rise speed = pressurization rate / (metal liquid density * gravitational acceleration * cross-sectional area of ​​riser pipe 4).

[0168] Ventilation parameters refer to parameters such as the time, speed, and flow rate of compressed gas entering and exiting the sealed crucible 3. Depending on the operator's selection, 3 to 5 lifting cycles are set, and the molten metal rises to 60% of the height of the riser pipe 4. The filling and exhaust flow rates are matched and obtained from the database based on the set or calculated values.

[0169] Step 46: Determine the scraping path based on the liquid level height and liquid level rise / fall parameters.

[0170] The scraping path refers to the movement trajectory of the permanent magnet 6, which is used to control the mass of the oxide film filling on the surface of the molten metal by the stirring rod 5. It is a circular basic trajectory set at a certain safe distance outside the diameter of the sealed crucible 3, and is located at the same level as the liquid surface. The spiral scraping trajectory is planned by combining the liquid surface rise and fall parameters with the circular basic trajectory using the Dijkstra algorithm.

[0171] Step 47: Based on the ventilation parameters, control the compressed gas to enter and exit the sealed crucible 3, and control the permanent magnet 6 to move from the surrounding path 7 to the scraping path, and continue to move to drive the stirring rod 5 to scrape off the oxide film and bubbles on the liquid surface, and stop running after a preset time and start to stand to complete the pre-filling preparation.

[0172] Based on the ventilation parameters, compressed gas is controlled to enter the sealed crucible 3 to squeeze the molten metal into the riser pipe 4. At this time, the liquid level will decrease. Then, the compressed gas is controlled to be discharged, and the molten metal in the riser pipe 4 flows back to the sealed crucible 3, at which point the liquid level will increase.

[0173] During the stirring process, some larger air bubbles may be broken into smaller air bubbles by the stirring rod 5 and float to the surface of the molten metal. When the molten metal is filled into the mold later, the small air bubbles may be carried into the mold cavity 11, which will have an adverse effect on the molded product.

[0174] The length of the stirring rod 5 is set according to the size of the sealed crucible 3 to ensure that when the stirring rod 5 is set at an inclined angle inside the sealed crucible 3, it can cover most of the molten metal area, while the sealed crucible 3 is large enough to accommodate the horizontal stirring rod 5.

[0175] The permanent magnet 6 moves from the surrounding path 7 to the scraping path. Since there is only one scraping path and it is at the same level as the liquid surface, the stirring rod 5 follows the permanent magnet 6 to the liquid surface and is in a horizontal state. The permanent magnet 6 moves along the scraping path to drive the stirring rod 5 to rotate along the liquid surface to scrape off the oxide layer filling mass of the liquid surface.

[0176] The pressure relief method includes the following steps: Step 90: In response to the pressure relief signal, read the molten metal flow rate from the product parameters and obtain the riser diameter.

[0177] The pressure relief signal is the instruction signal to start the pressure relief process. It is generated by the trigger condition that the judgment temperature is consistent with the reference temperature. It is automatically generated by the system when the judgment temperature is consistent with the reference temperature.

[0178] Metal molten fluidity refers to the ease with which a molten metal flows under pressure. It is related to the viscosity and temperature of the molten metal and can be directly obtained from product parameters.

[0179] The riser diameter refers to the inner diameter of riser 4, which is obtained in advance by staff through measurement and entered into the system.

[0180] Step 91: Determine the initial rate based on the fluidity of the molten metal and the diameter of the riser tube.

[0181] The initial rate refers to the initial gas discharge speed when the pressure relief process is started. It is determined by the fluidity of the molten metal and the diameter of the riser pipe. The specific calculation method is: initial rate = proportional coefficient * fluidity of molten metal / diameter of riser pipe. The proportional coefficient is calibrated in advance by the staff based on experimental data and entered into the system.

[0182] Step 92: Determine the valve opening angle based on the initial rate, control the valve to open based on the valve opening angle to begin depressurization, and collect real-time pressure.

[0183] The valve opening angle refers to the degree of opening of the pressure relief valve preset on the sealed crucible 3. The larger the valve opening angle, the faster the pressure relief rate. The corresponding valve opening angle is found from the angle correspondence table according to the initial rate. The angle correspondence table is a data table that records different initial rates and their corresponding valve opening angles. It is obtained by technicians through pre-testing and will not be elaborated here.

[0184] The pressure relief valve is opened based on the valve opening angle, and the compressed gas in the sealed crucible 3 is gradually discharged, and the pressure value gradually decreases. The pressure sensor preset in the sealed crucible 3 continuously collects and detects the data.

[0185] Step 93: Match the pressure relief path based on real-time pressure.

[0186] The pressure relief path refers to the specific combination of channels through which compressed gas is discharged during the pressure relief process, such as the main pressure relief channel and the auxiliary pressure relief channel. During the system design phase, multiple combinations of pressure relief channels are preset according to the pressure range of the sealed crucible 3 and stored in the pressure relief path library. For example, the auxiliary channel is used in the low pressure stage, and the main channel + auxiliary channel is used in the medium and high pressure stages.

[0187] Step 94: Control the corresponding valve to open according to the pressure relief path to switch paths.

[0188] The switching between multiple pressure relief channel combinations is controlled by opening and closing multiple corresponding valves.

[0189] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A method for temperature-controlled pressure relief at the gate of a low-pressure casting mold, characterized in that, include: Step 1: In response to the trigger signal, obtain the product parameters of the standard finished product based on the trigger signal; Step 2: Determine the filling pressure and reference temperature based on the product parameters; Step 5: Collect the real-time pressure inside the pre-set sealed crucible (3); Step 6: When the real-time pressure and the filling pressure are consistent, determine the compaction parameters according to the product parameters; Step 7: Based on the compaction parameters, the perforated push plate in the riser pipe (4) moves up and down reciprocally, and a cooling signal is issued after the movement is completed; Step 8: In response to the cooling signal, the molten metal extruded into the cavity (11) under pressure is gradually cooled from top to bottom using a preset cooling method, and the preset determination temperature at the gate ring (12) is collected in real time. Step 9: When the temperature is consistent with the reference temperature, the compressed gas is discharged from the sealed crucible (3) at a uniform speed using a preset pressure relief method.

2. The method for temperature control and pressure relief at the gate of a low-pressure casting mold according to claim 1, characterized in that, Between step 2 and step 5, the following is also included: Step 30: Obtain the filling image information of the filling block in the preset filling area and the edge image information of the edge block in the preset edge area; read the cavity parameters from the product parameters; and determine the filling features based on the cavity parameters. Step 31: When the image information contains filling features, load the material and output the filling receipt information; Step 32: When the filling image information does not contain filling features, determine the decomposition path based on the comparison relationship between the edge material image information and the filling features; Step 33: Decompose and load materials according to the decomposition path and output edge material receipt information to synchronously update edge material image information, or replenish materials using a preset replenishment method.

3. The method for temperature control and pressure relief at the gate of a low-pressure casting mold according to claim 2, characterized in that, Supplementary methods include: Step 330: Acquire detection image information of cropping blocks in the preset cropping area; Step 3310: When the detected image information does not cover the filling feature, define the clipping block as an edge block and control the edge block to be added to the edge area; Step 33110: When the image information detects the overlay and filling features, determine the cutting path based on the filling contour and cut and separate to obtain the filling block and the edge block; Step 33111: Control the filling block to replenish the filling area, and control the edge material block to replenish the edge material area.

4. The method for temperature control and pressure relief at the gate of a low-pressure casting mold according to claim 3, characterized in that, Step 30 is followed by: Step 340: Determine the filling volume based on the filling receipt information or edge material receipt information, and read the product density and specific heat capacity from the product parameters; Step 341: Calculate the fill mass based on the fill volume and product density; Step 342: Calculate the total volume of the molten metal based on the cavity parameters and filling volume, and read the molten metal density and specific heat capacity from the product parameters; Step 343: Calculate the mass of the molten metal based on the total volume and density of the molten metal; Step 344: Collect the ambient temperature of the cavity (11) and the initial temperature of the filling block or edge block, and determine the correction coefficient according to the cavity parameters; Step 345: Substitute the product specific heat capacity, filling mass, molten metal specific heat capacity, molten metal mass, ambient temperature, initial temperature, correction coefficient, and reference temperature into the preset thermal balance correction model calculation formula to calculate and determine the new reference temperature, thereby completing the correction of the reference temperature.

5. The method for temperature control and pressure relief at the gate of a low-pressure casting mold according to claim 1, characterized in that, Cooling methods include: Step 80: Determine the cavity height, cooling rate, and initial temperature value based on the cavity parameters; Step 81: Divide the cavity height according to a preset dividing distance to obtain a set of dividing heights, which includes several different dividing height values; Step 82: Determine the volume of liquid metal corresponding to the segmentation height value based on the segmentation height value and the cavity parameters, and determine the heat parameters based on the volume of liquid metal and the specific heat capacity of liquid metal; Step 83: Obtain the simulated temperature value corresponding to the segmentation height value based on the heat parameters and cooling rate, calculate the difference between the simulated temperature value and the initial temperature value, and define it as the heating parameter; Step 84: Determine the total voltage value based on the heating parameters and cooling coefficient, and calculate the mapping relationship between the total voltage value and the preset contact point voltage value to determine the number of contact points; Step 85: In response to the cooling signal, the mold is energized and heated at the cavity position corresponding to the segmentation height value according to the number of contact points, and then the preset cooling water is controlled to flow through the preset cooling water channel to cool the mold.

6. The method for temperature control and pressure relief at the gate of a low-pressure casting mold according to claim 5, characterized in that, Cooling methods also include: Step 86: Determine the water cooling rate based on the preset cooling water temperature and cooling water flow rate, and correct the water cooling rate based on the simulated temperature value; Step 87: Read the volume shrinkage rate from the product parameters, and calculate and determine the filling liquid volume based on the volume shrinkage rate and the volume of molten metal; Step 88: Determine the filling rate based on the filling liquid volume and the corrected water cooling rate; Step 89: Determine the inflation rate based on the filling rate, and control the continuous inflation of compressed gas into the sealed crucible based on the inflation rate (3).

7. The method for temperature control and pressure relief at the gate of a low-pressure casting mold according to claim 1, characterized in that, Between step 2 and step 5, the following is also included: Step 40: In response to the stirring information, collect the liquid level height and the position of the detection point in the preset stirring rod (5); Step 41: Determine the tilt angle of the stirring rod (5) based on the liquid level height, and determine the circumferential path (7) based on the tilt angle. The circumferential path (7) includes the upper circumferential path and the lower circumferential path. Step 42: Determine the adsorption position based on the detection point location, and determine the adsorption path based on the adsorption position, the preset permanent magnet position, and the surrounding path (7); Step 43: Control the two permanent magnets (6) preset on the outside of the crucible to move along the adsorption path to the adsorption position, and then move to the upper and lower surrounding paths respectively; Step 44: Control the permanent magnet (6) to move continuously along the surrounding path (7) to drive the stirring rod (5) to stir the molten metal.

8. The method for temperature control and pressure relief at the gate of a low-pressure casting mold according to claim 7, characterized in that, Step 44 is followed by: Step 45: Determine the liquid level rise / fall parameters and ventilation parameters based on the preset pressure rise rate and pressure fall rate; Step 46: Determine the scraping path based on the liquid level height and liquid level rise / fall parameters; Step 47: Based on the ventilation parameters, control the compressed gas to enter and exit the sealed crucible (3), and control the permanent magnet (6) to move from the surrounding path (7) to the scraping path, and continue to move to drive the stirring rod (5) to scrape off the oxide film and bubbles on the liquid surface, and stop running after a preset time and start to stand to complete the pre-filling preparation.

9. The method for temperature control and pressure relief at the gate of a low-pressure casting mold according to claim 1, characterized in that, Pressure relief methods include: Step 90: In response to the pressure relief signal, read the molten metal flow rate from the product parameters and obtain the riser diameter; Step 91: Determine the initial velocity based on the fluidity of the molten metal and the diameter of the riser tube; Step 92: Determine the valve opening angle based on the initial rate, control the valve to open based on the valve opening angle to start depressurization, and collect real-time pressure; Step 93: Match the pressure relief path based on real-time pressure; Step 94: Control the corresponding valve to open according to the pressure relief path to switch paths.

10. A low-pressure casting mold, controlled by a temperature-controlled pressure relief method at the gate of a low-pressure casting mold as described in any one of claims 1 to 9, comprising a casting structure (1) having a cavity (11), characterized in that, It also includes a temperature measuring structure (2) with a temperature measuring rod (22). One end of the cavity (11) is provided with a gate. The temperature measuring rod (22) is installed inside the casting structure (1) and is used to detect the temperature at the gate. The temperature measuring structure (2) also includes a heat-conducting ring (21) installed outside the gate ring (12). The heat-conducting ring (21) is used to reduce the interference of local fluctuations on the temperature measurement. The detection end of the temperature measuring rod (22) abuts against the outside of the heat-conducting ring (21).

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