A method, apparatus, and equipment for transferring the mold shell during investment casting.

Abstract

This application provides a method, apparatus, and equipment for transferring shells in the investment casting process, relating to the field of automatic control technology, to solve the technical problems of high labor intensity, high operational risk, low production efficiency, and poor quality consistency in manual shell transfer in related technologies. The method includes: after confirming that the loading pallet is in place and the safety door is closed, driving an industrial robot to transfer the cold shell to a baking furnace; after the cold shell is baked into a hot shell, driving the industrial robot to transfer the hot shell to the casting position of a vacuum casting furnace or a medium-frequency induction furnace to cast the hot shell into a casting; after casting is completed, driving the industrial robot to pick up the casting and transfer it to a unloading pallet for regular stacking.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of automatic control, and in particular to a method, device and equipment for transferring mold shells in a lost foam casting process. BACKGROUND

[0002] With the increasing demand for high-temperature alloy precision casting performance in high-end equipment manufacturing, the lost foam casting process is widely used in key fields such as aerospace and energy power. At present, in the production process of high-temperature alloy precision casting, the transfer of mold shells between the vacuum casting furnace, the intermediate frequency tilting furnace and the baking furnace is completed by manual operation, which is labor-intensive and risky. During the pouring and smelting period, personnel need to wait for a long time, and the labor efficiency is low. In the hot mold shell transfer process, the mold shell temperature directly affects the casting quality, and the duration and path of manual transfer of hot mold shells are uncertain. When the product quality is abnormal, there is a lack of effective recording and correlation analysis means for the related parameters of the mold shell transfer link, which restricts the traceability of the process and the improvement of the quality control ability. SUMMARY

[0003] To solve the above technical problems, the present application provides a method, device and equipment for transferring mold shells in a lost foam casting process to solve the technical problems of high labor intensity, high operation risk, low production efficiency and poor quality consistency in manual transfer of mold shells in related technologies.

[0004] To achieve the above technical purposes, the present application provides the following technical solutions: In a first aspect, the present specification provides a method for transferring mold shells in a lost foam casting process, comprising: After determining that the loading tray is in place and the safety door is closed, driving an industrial robot to transfer the cold mold shell to a baking furnace; After the cold mold shell is baked into a hot mold shell, driving the industrial robot to transfer the hot mold shell to a vacuum casting furnace or a medium-frequency tilting furnace pouring position to pour the hot mold shell into a casting; After pouring is completed, driving the industrial robot to clamp and transfer the casting to a discharging tray for regular stacking.

[0005] Through the scheme, under the premise that the feeding tray is transported to the specified station by the AGV and positioning is completed, and the safety door is in the closed state, the industrial robot is started to perform the grabbing and furnace entering operation of the cold state shell; after the shell completes the baking process, the transfer of the hot state shell to the casting equipment is triggered according to the out-of-furnace condition satisfaction signal; after the casting is completed, the clamp is automatically switched and the casting is taken out and regularly stacked. The whole process coordinates the action time sequence of each equipment through the PLC control system, and synchronously records the key process parameters to form a complete data closed loop. The method eliminates the path deviation and time fluctuation caused by manual intervention, ensures the temperature stability of the hot state shell in the transfer process, and provides structured data support for subsequent quality tracing.

[0006] Optionally, after determining that the feeding tray is in place and the safety door is in the closed state, the industrial robot is driven to transfer the cold state shell to the baking furnace, comprising: an upper feeding tray is in place signal is obtained, and whether the feeding tray is in place is determined according to the feeding tray in place signal; after determining that the feeding tray is in place and the safety door is in the closed state, the baking furnace door is opened; the industrial robot is driven to move to the shell taking position, the cold state shell is clamped and taken, and the cold state shell is transferred to the specified position in the baking furnace according to the preset path.

[0007] Through the scheme, two inductive proximity switches installed on both sides of the feeding station are used to detect the insertion state of the left and right positioning pins of the tray. When both switches output high level signals at the same time, the PLC determines that the AGV has completed accurate parking. If any switch is not triggered, the robot operation is suspended and the "tray not in place" alarm icon in the HMI interface is activated. The furnace door opening instruction is driven by the PLC digital output module through the intermediate relay to drive the pneumatic electromagnetic valve, so that the furnace door cylinder extends. After the upper limit position magnetic switch of the furnace door feeds back the closed signal, the interlocking restriction of the robot entering the baking furnace area is released. The robot runs to the taking point along the collision-free trajectory generated by offline programming, uses the self-designed non-standard clamp to fix the shell, and lifts and moves into the specified shelf coordinates of the furnace according to the set acceleration curve.

[0008] Optionally, after the cold state shell is baked into a hot state shell, the industrial robot is driven to transfer the hot state shell to the vacuum casting furnace or the intermediate frequency tilting furnace casting position, so as to cast the hot state shell into a casting, comprising: after the baking furnace door is closed and the industrial robot exits the non-interference area, a target heating temperature instruction is sent to the baking furnace temperature control system, and the furnace temperature and heating current data are collected in real time; in response to the out-of-furnace condition satisfaction signal, the baking furnace door is opened, and the out-of-furnace condition satisfaction signal is determined according to whether the temperature in the baking furnace reaches the set value and the holding time is completed; The industrial robot is driven to pick up the hot shell and transfer it to the casting position of the vacuum casting furnace or the medium-frequency turning furnace.

[0009] In this scheme, the roasting furnace temperature controller receives the target temperature value sent by the PLC via RS485 bus through the Modbus RTU protocol; the three-phase heating circuit current is sampled by a through-type current transformer and input to the PLC analog module via a 4–20mA current transmitter; when the current value of any phase is lower than 10% of the rated value for 5 consecutive seconds, the PLC cuts off the heating contactor and sets the "heating fault" flag. The furnace discharge condition meeting signal is generated by the internal logic of the temperature controller. When the furnace temperature is within the set value ±5℃ for the full holding time, the temperature controller's DO port outputs a high level. Before the robot grips the hot shell, it moves to the simulation mold tooling to perform a simulation cycle: confirming the transfer path and action point, locking the quick-change plate of the clamp, testing the response time of the vacuum furnace door opening and closing, and verifying the feedback from the medium frequency furnace clamping plate positioning sensor; if all I / O signals return normally within 3 seconds, the formal transfer process is allowed.

[0010] Optionally, acquiring the loading pallet arrival signal includes: Detect whether the two positioning proximity switches simultaneously output a high-level signal; If both positioning proximity switches output high-level signals, it is determined that the AGV has transported the loading pallet to the designated workstation and completed the positioning. If any positioning proximity switch does not output a high-level signal, the robot's movement will be paused and an alarm indicating that the tray is not in place will be triggered.

[0011] This solution employs a dual proximity switch redundant detection mechanism, which determines that the pallet is accurately positioned only when both positioning signals are valid simultaneously. This greatly improves the reliability and safety of positioning judgment, effectively avoids the risk of robot malfunction due to false triggering of a single sensor or positioning deviation, and ensures that the reference position for subsequent material handling operations is accurate.

[0012] Optionally, before driving the industrial robot to grip the hot shell and transfer it to the casting position of the vacuum casting furnace or the medium-frequency induction furnace, the method further includes: Control the industrial robot to move to the simulated mold position and execute a simulated gripping-placing-removing cycle; In the simulation cycle, the accuracy of the control at each point in the shell transfer process, the locking status of the quick-change plate of the fixture, the opening and closing response time of the vacuum furnace door, and the positioning signal of the medium frequency tilting furnace clamp are verified. If all control points in the simulation cycle operate normally and the I / O signals are fed back normally within the preset time limit, then the formal hot shell transfer process will begin. If any control point activates, signals time out, or becomes abnormal, the process is interrupted and the corresponding fault point is indicated. At the same time, the action points of the transfer process can be adjusted through the human-machine interface.

[0013] This solution pre-verifies the robot's path accuracy, fixture status, and equipment linkage response through a full-process simulation before the formal transfer of the high-temperature shell. This "pre-simulation" mechanism can expose and locate potential faults in the mechanical, electrical, or control logic in advance, preventing accidents during actual high-temperature and high-risk operations. Simultaneously, it provides human-machine interface adjustment functions, enabling the system to have a certain degree of self-adaptation and debugging capabilities, thus improving the reliability, safety, and maintainability of the entire transfer system.

[0014] Optionally, sending the target heating temperature command to the calcining furnace temperature control system and collecting furnace temperature and heating current data in real time includes: The target temperature value is written to the roasting furnace temperature controller via the RS485 communication interface; The current of the three-phase heating circuit is collected by a current transformer and converted into a 4–20mA analog signal by a current transmitter and input to the PLC. If the current in any phase is lower than the set threshold and lasts for more than 5 seconds, it is determined that the heating element is open-circuited, heating is stopped and an alarm is triggered. The temperature and current values ​​collected every second are packaged and stored to generate a timestamped process data block.

[0015] This solution enables digital remote setting and high-frequency real-time monitoring of the roasting furnace heating process. The communication interface ensures accurate transmission of process parameters; continuous monitoring of the heating current allows for timely diagnosis of faults such as open circuits in heating elements, preventing ineffective heating or equipment damage; and structured storage of all key temperature control process data (temperature and current) bound to timestamps provides a complete and traceable data archive for each roasting process, forming a solid foundation for subsequent quality analysis and process optimization.

[0016] Optionally, the process of driving the industrial robot to grip the castings and transfer them to the unloading pallet for regular stacking includes: After casting is completed, the automatic fixture switching command is triggered based on the casting end signal fed back by the vacuum casting furnace or the medium frequency tilting furnace. Control the quick-change disc to release the long clamp rod and install the short clamp rod; Drive the robot to the casting removal position, clamp the casting, and then check whether the air pressure of the gripper is within the range of 3.5–4.5 bar and maintains it stably for 2 seconds; If the air pressure is within the specified range and the gripper position sensor shows that it is in the middle stroke, the gripping is considered successful and the stacking action is executed. If the air pressure is abnormal or the gripper is in the extreme position, it is determined to be an empty gripper, and the system will return to retry or issue an alarm.

[0017] This solution achieves full automation of the removal and stacking of finished castings after casting. Based on the casting completion signal, it automatically switches to a short clamp adapted to the weight of the casting, ensuring gripping stability. Through real-time feedback from both gripper air pressure and position sensors, it intelligently determines the gripping status (successful gripping or empty gripping), avoiding drops, collisions, or ineffective handling due to gripping failures. This greatly improves the reliability, automation level, and production safety of the unloading process.

[0018] Optionally, the rule stacking also includes fabric rule settings and optimization: Based on the specifications and quantity of the products to be processed, preset fabric specifications and rules are set or called in the loading tray, unloading tray and roasting oven; Based on the aforementioned fabric rules, the transfer path and placement position of the industrial robot within the roasting furnace are planned to shorten the overall transfer time and path, and the uniform temperature area within the roasting furnace is prioritized for shell placement.

[0019] This solution upgrades simple "stacking" to intelligent "material planning and optimization." The system can dynamically adjust the material layout rules throughout the entire process of feeding, baking, and unloading based on product information, thereby optimizing the robot's movement path. Its core benefits are: shortening the single-cycle time and improving production efficiency through path optimization; and improving the uniformity of shell heating by prioritizing the use of the uniform temperature zone in the baking furnace, directly enhancing the quality of the baking process and product consistency, thus achieving dual optimization of efficiency and quality.

[0020] Optionally, if the method further includes synchronously recording equipment action time, furnace temperature curve, furnace door opening and closing status, fixture switching signals, and robot trajectory data during execution, and storing the data in a real-time database, then the method may also include: When product quality is abnormal, retrieve the complete hot shell transfer data package of the corresponding production order; Analyze whether the time interval between the hot shell being removed from the furnace and the start of casting exceeds 15 seconds; Check the ambient temperature and whether there are any obstructions or delays in the robot's path during this time period; If the time interval exceeds the limit, the shell transfer process will be marked as a potential influencing factor.

[0021] This solution establishes a quality traceability and causal analysis capability based on full-process data collection. When product quality anomalies occur, the system can quickly trace back and focus on the critical "hot shell transfer" step. By quantitatively analyzing multi-dimensional data such as transfer time, environmental interference, and equipment status, the contribution of this step to quality defects can be scientifically assessed. This enables precise location of quality problems, transforming traditional experience-based judgment into data-driven decision-making, and providing a clear direction for continuous process improvement.

[0022] Optionally, controlling the opening of the roasting furnace door includes: The PLC output signal is transmitted via a relay to energize the solenoid valve of the furnace door cylinder. Check whether the upper limit magnetic switch of the furnace door changes from normally open to closed; If no upper limit signal is received within 5 seconds, the power supply to the solenoid valve will be cut off and an alarm will be triggered to warn of furnace door jamming. Only after receiving the upper limit signal will the robot's motion interlock be released, allowing it to enter the interior area of ​​the roasting furnace.

[0023] This solution adds a safety interlock and fault diagnosis mechanism to the automatic opening of the roasting furnace door. By monitoring the feedback time of the upper limit signal, it can determine in real time whether the furnace door movement is completed normally. If the timeout is exceeded, it is judged as jamming, and the power is immediately cut off and an alarm is triggered to prevent equipment damage. The strict "interlock released after signal confirmation" logic ensures that the robot will never enter the interference zone before the furnace door is fully and safely opened, fundamentally avoiding the major safety hazard of robot collision with the furnace body and improving the overall safety of equipment operation.

[0024] Secondly, embodiments of this specification provide a shell transfer device for an investment casting process, comprising: The first drive unit is used to drive the industrial robot to transfer the cold shell to the calcining furnace after confirming that the feeding tray is in place and the safety door is closed. The second drive unit is used to drive the industrial robot to transfer the hot shell to the casting position of the vacuum casting furnace or the medium frequency turning furnace after the cold shell is baked into a hot shell, so as to cast the hot shell into a casting. The third drive unit is used to drive the industrial robot to pick up the casting and transfer it to the unloading pallet for regular stacking after the casting is completed.

[0025] Thirdly, the present invention provides a computer device, comprising: a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, and the processor executing the computer instructions to perform the method for transferring the mold shell in the investment casting process described in the first aspect or any corresponding embodiment.

[0026] Fourthly, embodiments of this specification provide a computer-readable storage medium storing a computer program that, when executed by a processor, implements the shell transfer method for the investment casting process as described in any of the preceding claims.

[0027] Fifthly, embodiments of this specification provide a computer program product or computer program, the computer program product including a computer program stored in a computer-readable storage medium; the processor of the computer device reads the computer program from the computer-readable storage medium, and when the processor executes the computer program, it implements the shell transfer method in the investment casting process as described in any of the preceding claims. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0029] Figure 1 A schematic flowchart illustrating a method for transferring a mold shell during an investment casting process, provided for the implementation of embodiments of this specification; Figure 2 A schematic diagram of a device for transferring a mold shell in an investment casting process, provided for the implementation of embodiments of this specification; Figure 3 This is a schematic diagram of the structure of an electronic device provided for the implementation of this specification. Detailed Implementation

[0030] Unless otherwise defined, the technical or scientific terms used in the embodiments of this specification shall have the ordinary meaning understood by one skilled in the art to which this specification pertains. The terms "first," "second," and similar terms used in the embodiments of this specification do not indicate any order, quantity, or importance, but are merely used to avoid confusion of constituent elements.

[0031] Unless the context otherwise requires, throughout this specification, "a plurality of" means "at least two," and "including" is interpreted as open-ended or encompassing, that is, "including, but not limited to." In the description of this specification, terms such as "one embodiment," "some embodiments," "exemplary embodiment," "example," "specific example," or "some examples" are intended to indicate that a particular feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example of this specification. The illustrative representations of the above terms do not necessarily refer to the same embodiment or example.

[0032] The technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this specification, and not all embodiments. Based on the embodiments in this specification, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this specification.

[0033] SUMMARY As mentioned in the background technology, with the increasing demands on the performance of high-temperature alloy precision castings in high-end equipment manufacturing, investment casting technology has been widely used in key fields such as aerospace and energy. Currently, in the production process of high-temperature alloy precision casting, the transfer of the mold shell between the vacuum casting furnace, the medium-frequency induction furnace, and the calcining furnace is all done manually. This is labor-intensive, high-risk, and requires personnel to wait for long periods during casting and smelting, resulting in low labor efficiency. During the transfer of the hot mold shell, the temperature of the mold shell directly affects the quality of the casting, and the duration and path of manual transfer of the hot mold shell are uncertain. When product quality abnormalities occur, the lack of effective recording and correlation analysis methods for relevant parameters in the mold shell transfer process restricts the improvement of process traceability and quality control capabilities.

[0034] Based on the above inventive concept, the following is an exemplary description of the shell transfer method in the investment casting process provided in the embodiments of this specification.

[0035] Exemplary method This specification provides a method for transferring the mold shell in the investment casting process. Through the collaborative work of an automated control system and an industrial robot, the efficient transfer of the mold shell between a vacuum casting furnace, a medium-frequency induction furnace, and a calcining furnace is achieved. The following detailed description, in conjunction with specific embodiments not shown in the accompanying drawings, illustrates this method. Figure 1 As shown, it includes: S101. After confirming that the feeding tray is in place and the safety door is closed, drive the industrial robot to transfer the cold shell to the calcining furnace.

[0036] In practical implementation, in an automated production line integrating an automatic feeding system, a roasting furnace, an industrial robot, a vacuum casting furnace or a medium-frequency induction turning furnace, and a unloading system, two positioning proximity switches are first installed at the feeding station, one on the left and one on the right of the pallet positioning pin, to detect whether the feeding pallet transported by the AGV is accurately positioned. When the AGV transports the feeding pallet carrying the cold shell to the robot's picking area, both positioning proximity switches are simultaneously triggered and output high-level signals to the PLC control system. Upon receiving these dual high-level signals, the PLC, combined with the safety door closed status signal (provided by the limit switch on the safety door), determines that the start-up conditions are met and then activates the automatic transfer process. If either proximity switch fails to output a high level, the PLC pauses the robot's subsequent actions and displays an "pallet not in place" alarm message through the HMI interface, while simultaneously recording the current timestamp and equipment status.

[0037] The roasting furnace door is driven by an SC63×200 double-acting cylinder. The cylinder's air inlet is connected to a compressed air source via a two-position five-way solenoid valve. The solenoid valve coil is controlled by the PLC's DO module output point Q0.0. An upper limit magnetic switch is installed on the top of the furnace door, with its signal connected to the PLC input point I0.3. When the furnace door is fully opened, this switch is triggered, and the PLC releases the movement restrictions on the robot entering the roasting furnace area.

[0038] The industrial robot is an ABB IRB 6700-200 / 2.6 six-axis articulated robot, with a quick-change disc female head mounted on the end flange, which is connected to the fixture male head via a pneumatic locking mechanism. During the cold-state shell transfer stage, a self-designed non-standard fixture is used, which can be used with different shell shapes to achieve stable transfer.

[0039] Following the offline programming path, the robot moves from the standby position to the mold shell picking position, with coordinates set at (X=1250mm, Y=-320mm, Z=850mm). It adjusts the end effector to make the non-standard clamp parallel to the mold shell for clamping and fixing. Then, it is lifted to a safe height of Z=1100mm with an acceleration of 0.3g, and then moved to the coordinates in front of the furnace inlet (X=2100mm, Y=0mm, Z=1100mm). Finally, it descends to the designated position on the furnace shelf (X=2100mm, Y=0mm, Z=600mm) to release the vacuum, completing the cold mold shell loading into the furnace.

[0040] After confirming the feeding tray is in place and the safety door is closed, the PLC outputs a control signal to the relay coil circuit of the solenoid valve of the furnace door cylinder, causing the relay contacts to close. This energizes the 24VDC solenoid valve, pushing the piston rod of the furnace door cylinder to extend and opening the furnace door upwards. A magnetic limit switch is installed on the top of the furnace door. This switch is a normally open reed switch structure, fixed to the furnace frame, with a permanent magnet installed corresponding to the top of the furnace door. When the furnace door is fully opened to the upper limit, the permanent magnet approaches the reed switch, causing its internal contacts to close and sending a high-level signal back to the PLC input module. The PLC is set to a 5-second timeout timer. If the upper limit signal is not received within this time, the power supply circuit of the solenoid valve is immediately cut off, and a "furnace door jamming" fault code is triggered. At the same time, the robot's access to the interior area of ​​the furnace is locked. Only when the PLC confirms receipt of the furnace door upper limit signal is the robot's motion interlock released, allowing it to enter the material handling coordinate system before entering the furnace.

[0041] The industrial robot is a six-axis articulated robot, with its base fixed to a pre-embedded steel plate in the ground. Its end flange is equipped with a quick-change disc female head, which mates with the quick-change disc male head of the fixture. The fixture includes two types: a long clamping rod and a short clamping rod. The long clamping rod is 1200mm long with a rated load of 30kg, used for gripping cold, empty shells; the short clamping rod is 800mm long with a rated load of 90kg, used for gripping castings after casting. The quick-change disc consists of a pneumatic locking mechanism. A three-position five-way solenoid valve is controlled by a PLC outputting a DO signal to switch the air path, achieving automatic release and locking of the fixture. During the cold shell transfer stage, the robot first moves to the shell picking position. The coordinates of this position are calibrated using a laser tracker to ensure a repeatability accuracy within ±2mm. The robot's end effector descends to a preset height, compressed air is introduced into the gripper cylinders, and the grippers close to clamp the neck of the shell. The gripper integrates a position sensor to detect whether it is in the middle of its stroke position. Simultaneously, a pressure transmitter is installed in the air circuit to monitor whether the gripping air pressure remains stable within the range of 3.5–4.5 bar for more than 2 seconds. If both conditions are met, the gripping is considered successful. The robot then lifts the shell according to a preset path, bypasses surrounding equipment obstacles, and enters the roasting furnace using a linear interpolation method, placing the shell into the designated hole in the heat-resistant steel support inside the furnace. After placement, the gripper releases, and the robot exits the roasting furnace area.

[0042] After the robot completely exits the non-interference zone of the roasting furnace (this zone is marked by an electronic fence using a laser scanner and linked to the PLC safety module), the PLC sends a Modbus RTU protocol command to the roasting furnace temperature controller via the RS485 communication interface, writing the target heating temperature value, such as 1250℃. Upon receiving the command, the temperature controller starts the heating program. Simultaneously, each phase conductor of the three-phase heating circuit passes through an independent current transformer. The secondary output of the transformer is connected to a current transmitter, converting the 0–5A AC current into a 4–20mA standard analog signal, which is then connected to the PLC's AI module channels 1, 2, and 3, respectively. The PLC collects the current value of each phase and the temperature value fed back by the thermocouples inside the furnace every second. When the current of any phase falls below a set threshold (e.g., 8A) for more than 5 seconds, the PLC determines that the heating element of that phase is open-circuited, immediately outputs a DO signal to cut off the power supply to the heating contactor coil, and displays a "Heating Circuit Fault" alarm on the HMI. All collected temperature and current data are packaged into groups per second, with timestamps, production order numbers, and equipment IDs added to form process data blocks, which are then uploaded to a real-time database server for storage via the OPC UA protocol.

[0043] To achieve stable positioning and regular stacking of the mold shells during transport, this invention designs a dedicated tooling system, mainly comprising a sandbox base and a transport pallet. The sandbox base is a welded steel frame structure with positioning grooves or claws on its upper surface that match the shape of the bottom of the mold shells. This securely holds the cold or hot mold shells during transport and firing, preventing displacement or tipping when the robot moves at high speed or when heated inside the furnace. The bottom of the sandbox base has a standard interface for quick docking with the robot's long clamping rod (for empty shells) or short clamping rod (for shells with castings). The transport pallet is made of heat-resistant steel and has a multi-layered frame structure. The pallet has a array of positioning holes or guide grooves that match the bottom of the sandbox base, ensuring that each sandbox base can be accurately and repeatedly placed in the predetermined position. The loading pallet is used to carry the sand box base with the cold shell and is transported to the robot picking position by AGV; the unloading pallet is used to receive the sand box base with the casting after casting and stack it according to the production order information. The stacking logic is dynamically calculated by PLC based on the pallet RFID tag information and the casting size in the database.

[0044] This specialized tooling system, combined with the robot's high repeatability positioning accuracy (±2mm), ensures the consistency and reliability of positioning throughout the entire process from material picking, transfer, furnace entry to material discharge and stacking.

[0045] S102. After the cold shell is baked into a hot shell, drive an industrial robot to transfer the hot shell to the casting position of a vacuum casting furnace or a medium-frequency rotating furnace to cast the hot shell into a casting.

[0046] In practice, once the furnace temperature reaches the set value and the preset holding time (e.g., 60 minutes) is completed, the temperature controller sends a "holding time complete" signal to the PLC via hardwired wiring. Upon receiving this signal, the PLC controls the furnace door to open again, following the same door opening logic as described above. After the furnace door is fully open, the robot switches to hot-state transfer mode. Before officially gripping the hot-state shell, to ensure the reliability of the shell transfer process, the system first performs a simulated cycle verification. The robot moves to the simulated shell mounting position. This simulated shell is made of stainless steel, with dimensions identical to the real shell, and is fixed on a heat-resistant bracket at a standard test point within the robot's working envelope. The robot uses the current gripper to perform a complete simulated cycle: gripping the simulated shell → moving to the virtual furnace outlet → simulating placement into the vacuum casting furnace ingot mold chamber tray position → then removing and returning to the original position. During this process, the system verifies the control accuracy of each preset point on the shell transfer path (e.g., the robot's repeatability and relative position to the furnace door). Simultaneously, the PLC monitors multiple I / O signals: robot motion path and action points, quick-change plate locking confirmation signal (from the proximity switch of the quick-change plate body), vacuum casting furnace door opening and closing response time (feedback via furnace door limit switch), and medium-frequency tilting furnace clamping plate positioning signal (from hydraulic cylinder limit switch). If the robot motion path and action points are normal, and all signals are fed back normally within the preset time limit (e.g., 3 seconds), the PLC allows the formal hot shell transfer to begin. If any signal times out or is abnormal (e.g., abnormal path or position, quick-change plate not locked, furnace door not opened within 2 seconds), the process is interrupted, the fault point is recorded, and an alarm is issued. If the action point is abnormal, the operator can directly adjust the position through the human-machine interface. The operator can adjust and optimize the coordinates and path parameters of the action point that has deviated or is abnormal through the on-site human-machine interface. The automatic transfer process can only be resumed after the adjustment is completed and re-verified.

[0047] In one example, each phase of the three-phase heating circuit of the roasting furnace is connected in series with a CT-50A / 5A through-type current transformer. The secondary output is connected to the PLC analog input module channels AIW0, AIW2, and AIW4 via a 4–20mA current transmitter. The PLC monitors the three-phase current in real time. If the current of any phase is lower than 10% of the rated current (i.e., lower than 0.5A) for 5 consecutive seconds, the heating element is determined to be abnormal, the heating contactor of that phase is disconnected, and an alarm is triggered.

[0048] The temperature controller is a Shimaden SRS13, which communicates with the PLC via the Modbus RTU protocol. The target temperature value is written to register 40001. When the furnace temperature reaches the set value within ±5℃ and is maintained for a holding time (e.g., 30 minutes), the temperature controller's DO port outputs a high level to the PLC input point I0.6 as a signal that the furnace discharge condition has been met.

[0049] During the transfer of hot-formed shells, the robot pre-equips the gripper with a longer gripper, and the non-standard end gripper is made of high-temperature resistant metal, capable of withstanding temperatures up to 1200℃ for extended periods. Based on the equipment type flag M20.0 (0 for vacuum furnace, 1 for medium-frequency furnace) in the order parameters issued by the MES system, the robot plans the corresponding path: if it is a vacuum casting furnace, it moves to the casting position coordinates (X=3200mm, Y=400mm, Z=900mm); if it is a medium-frequency rotating furnace, it moves to the coordinates (X=3200mm, Y=-400mm, Z=900mm).

[0050] During the formal hot shell transfer, the robot enters the baking furnace at maximum speed along a preset trajectory, gripping the pre-baked hot shell (temperature approximately 1250℃). The entire process employs a path planning that combines linear motion with circular transitions, ensuring the transfer time from furnace exit to the casting position is strictly controlled within 15 seconds. After the robot reaches the casting position of the vacuum casting furnace or medium-frequency induction furnace, it executes different docking logic depending on the equipment type: For a vacuum casting furnace, the PLC communicates with the furnace PLC via the ProfiNet protocol to obtain the material temperature, spindle height, vacuum level, and furnace door permission signal; only when the material temperature reaches the refining temperature, the vacuum level is ≥100,000 Pa, the spindle is stopped at the 0 point position, and the furnace door is allowed to open, is the furnace door opening command triggered, guiding the robot to accurately place the shell into the ingot mold chamber tray positioning point. For a medium-frequency induction furnace, the shell transfer and placement can only proceed after the furnace body has completed preheating, the crucible is in the horizontal casting position, and the clamped casting is in the open position. After the mold shell is placed, the robot exits, and the casting equipment starts the casting process.

[0051] To address the high precision requirements of the casting position alignment in medium-frequency rotary kilns, this invention employs an auxiliary visual positioning scheme. A graduated laser level is installed above the kiln opening as a calibration benchmark. Before each production run or after a kiln change, the laser level is activated, projecting a clear crosshair onto the center of the kiln opening. The robot, using a vision camera on its end effector or by manually teaching via a human-machine interface button, aligns the center of the end effector with the center of the crosshair, thus quickly and accurately calibrating the casting position coordinates. This measure effectively compensates for deviations caused by equipment installation and thermal deformation, ensuring repeatability and accuracy in placing the hot-state mold shell.

[0052] S103. After casting is completed, drive the industrial robot to pick up the casting and transfer it to the unloading pallet for regular stacking.

[0053] In practice, after casting is completed, the vacuum casting furnace or medium-frequency tilting furnace sends a "casting complete" signal to the main PLC via ProfiNet. Upon receiving this signal, the PLC immediately sends a fixture switching command to the robot controller. The robot moves to the quick-change station, which is fixed within the robot's working radius and includes storage seats for long and short fixture rods and pneumatic / electrical connection interfaces. The robot's end effector quick-change plate docks with the quick-change station, and the PLC controls the solenoid valve to switch the pneumatic path, releasing the current fixture and then grabbing and locking the short fixture rod. After the fixture switching is completed, the robot moves to the casting removal position of the vacuum casting furnace or medium-frequency tilting furnace, executing different docking logic depending on the equipment type: for a vacuum casting furnace, the corresponding position is the ingot mold chamber positioning tray; for a medium-frequency tilting furnace, this position is located at the part removal port below the tilting furnace. During casting transfer, the grippers close to clamp the casting body, and the PLC reads the values ​​of the gripper's air pressure sensor and the status of the position sensor. If the air pressure is between 3.5 and 4.5 bar and maintained for 2 seconds, and the position sensor shows that the gripper is in the middle stroke (not fully open or fully closed at the limit position), then the gripping is considered successful; otherwise, it is considered an empty grip, the robot returns and tries again, and if it still fails, it will alarm and stop.

[0054] To achieve efficient and stable rule-based placement, the system has fabric rule setting and optimization functions. Specifically: Loading and unloading rules: Based on the production order information (including casting model, size, and batch quantity) issued by the MES system, the system can automatically or manually set the material distribution specifications of the loading and unloading pallets on the host computer. For example, determining the number of rows and columns, layers, and spacing of castings on the pallets to ensure neat stacking and structural stability.

[0055] Material placement rules within the roasting furnace: Based on product specifications and quantity, the system can automatically or manually set the placement rules within the roasting furnace. Its core optimization objective is to minimize the robot's path and time for each transfer while ensuring uniform heating of the mold shells, and to fully utilize the area with the best temperature uniformity within the roasting furnace. The control system dynamically calculates and allocates the optimal placement coordinates for each mold shell on the furnace support based on the mold shell dimensions and the furnace temperature field distribution model, prioritizing placement within known uniform temperature zones to reduce roasting temperature differences and improve product quality consistency.

[0056] Path optimization: Considering multiple target locations such as the feeding point, the furnace inlet, various placement points inside the furnace, the casting position, and the unloading point, the robot control system adopts a path optimization algorithm to plan a global motion trajectory with the shortest total time, smooth movements, and no collisions.

[0057] In one example, after casting is completed, the vacuum casting furnace outputs a signal to PLC input point I0.7 after the pressure sensor detects that the furnace pressure has returned to normal. The medium-frequency tilting furnace outputs a signal to PLC input point I0.8 through a proximity switch after its rotary mechanism encoder returns to zero. Upon receiving either signal, the PLC triggers a fixture switch: first, it controls point DO Q0.1 to output a high level, causing the quick-change plate cylinder to retract and release the long fixture rod; after a delay, Q0.2 outputs a high level, pushing the short fixture rod to insert and lock.

[0058] The short clamping lever uses an SMC MHZ2-32D pneumatic parallel gripper with a built-in magnetostrictive displacement sensor. The output signal is connected to the PLC analog module AIW6. A Honeywell MPR series pressure sensor is installed on the air supply line, outputting a 4–20mA signal to AIW8. After the gripper closes, the PLC reads the pressure value on AIW8. If it is within the range of 3.5–4.5 bar for 2 seconds, and AIW6 displays that the gripper displacement is within the effective clamping range of 15–25 mm, then the clamping is considered successful; otherwise, a retry or alarm is triggered.

[0059] For the specialized clamps used in medium-frequency rotary kilns, a proportional pressure regulating valve is integrated into the gas circuit. The PLC can output different analog signals to the proportional pressure regulating valve based on the weight and material of different shells (order process information obtained through the MES system), thereby precisely controlling the air inlet pressure of the gripper cylinders and achieving stepless adjustment of the clamping force. This ensures reliable clamping of fragile shells without damage, as well as a firm grip on heavier castings, enhancing the clamp's process adaptability and flexibility.

[0060] After successful gripping, the robot moves the casting to the unloading pallet according to the product specifications and quantity, following an automated or manually preset stacking program. The unloading pallet is positioned at designated coordinates by the AGV, and its surface is divided into multi-row, multi-column matrix placement areas, with the size of each area set according to the shape of the casting. Based on the quantity of castings in the current production batch and the remaining space on the pallet, the robot dynamically calculates the stacking coordinates and arranges the castings in a regular manner to avoid stacking or misalignment. For each casting placed, the PLC records its row and column number, placement time, and robot end-effector posture data.

[0061] Throughout the entire transfer process, the PLC synchronously collects and records the following data: the start and end times of the actions fed back by the servo drives of each robot axis, the real-time temperature curve returned by the furnace temperature controller via Modbus, the time points of the on / off state changes of the magnetic switch of the furnace door cylinder, the I / O signal timing during quick-change plate switching, and the robot TCP trajectory point coordinate sequence (sampling period 10ms). All data is archived by production order number and stored in a real-time SQL Server database, retained for at least six months. When subsequent quality inspections discover defects such as shrinkage cavities or cracks in the casting, quality engineers can retrieve the complete hot shell transfer data package for the corresponding order and focus on analyzing the time interval from the hot shell exiting the furnace to the start of casting. If this interval exceeds 15 seconds, the system automatically marks "transfer delay" as a potential influencing factor and associates it with the quality file of that casting. At the same time, it can trace back the workshop ambient temperature (provided by temperature and humidity sensors installed near the robot), whether there are temporary obstacles on the robot path (compared with historical data from a safety laser scanner), and whether there are equipment communication delays (analyzed through PLC and subsystem communication logs), thereby comprehensively assessing the impact of the transfer process on the casting quality.

[0062] In one example, the PLC records the timestamps of each key event through an internal real-time clock, periodically reads the angles of each joint of the robot and the coordinates of the end effector through the Ethernet / IP interface, and periodically reads the furnace temperature data through Modbus. All data is packaged and stored in the InfluxDB time-series database according to the production order number.

[0063] When quality inspection detects casting defects, the system retrieves the corresponding order's hot transfer data package and calculates the time interval from the moment the hot shell exits the furnace (rise edge of I0.6) to the moment it reaches the casting position. If it exceeds 15 seconds, further analysis is performed: the robot trajectory is compared with the workshop SLAM map, or the video monitoring system is used to determine whether any avoidance or path detours occurred during the transfer process; data from environmental temperature and humidity sensors (such as Sensirion SHT35, signal input AIW10, AIW12) and an infrared thermometer (such as Optris CTlaser 3M) installed on the robot's sixth axis are read to analyze the shell surface temperature decay curve. If the temperature is below the process threshold (such as 1250℃), the transfer link is marked as a potential quality influencing factor in the MES system, and a multi-dimensional traceability report is generated.

[0064] The hardware connections involved in this embodiment are as follows: The PLC is a Siemens S7-1500 series, and the CPU module is connected to the industrial robot controller, the vacuum casting furnace PLC and the medium-frequency reversing furnace PLC through the ProfiNet interface; the roasting furnace temperature controller (model Shimaden SRS13) is connected through the RS485 serial port module (CM1241); the digital input module (SM1221) is connected to two feeding tray positioning proximity switches (model Omron E2E-X10ME1), the furnace door upper and lower limit magnetic switches (SMC D-M9BL), and the safety door limit switch; the digital output module (SM1222) controls the furnace door solenoid valve relay, the quick-change plate solenoid valve, and the alarm indicator light; the analog input module (SM1231) is connected to three current transmitters (model WEIGEL EQ72K) and the gripper pressure sensor (model SICK PBS-HD30). The robot's end effector quick-change panel (model ATI QRC-50) connects the pneumatic (4-way) and electrical (8-pin) circuits via an M12 aviation connector. The pneumatic circuit is supplied centrally from the factory, passes through a pressure reducing filter, and then connects to a three-position five-way solenoid valve (FestoMHJ9-MS), before reaching the quick-change panel. All equipment grounding conforms to GB 5226.1 standard. Communication cables are shielded twisted-pair cables with single-end grounding. Analog signal lines and power lines are laid in separate channels with a spacing greater than 300mm to suppress electromagnetic interference.

[0065] The automatic transfer system of this invention is designed with complete interfaces for anomaly handling and manual intervention. When the system detects any critical signal anomaly during automatic operation (such as sensor timeout without feedback, excessive air pressure / current values, communication interruption, etc.), the PLC will immediately pause the current process, display clear fault alarm information on the HMI interface (such as "safety door closing signal lost", "quick change plate not locked", "heating current abnormal"), and trigger the audible and visual alarm.

[0066] At this point, the operator can switch the system to "manual" mode using the knob on the on-site control box. In manual mode, individual devices can be operated independently via the soft buttons on the HMI or the hard buttons on the control box, such as manually opening and closing the safety door, manually controlling the furnace door cylinder, manually starting and stopping the heating, and manually controlling the clamp movements. This allows maintenance personnel to systematically check sensor status, inspect wiring for looseness, and confirm the normal operation of the gas / power supply based on alarm prompts.

[0067] Once the fault has been cleared and all signals have returned to normal, operators can manually reset each device to its safe initial state before switching back to "automatic" mode. Before re-executing the automatic process, the system typically requires another simulation cycle to verify that all system functions have returned to normal. This mechanism ensures that in the event of automation failure, production can still continue or be resumed through safe and controlled manual intervention, minimizing unplanned downtime.

[0068] In one example, the mold shell transfer method described in this invention is used in a precision casting production line for high-temperature alloy turbine blades of an aero-engine. This production line is equipped with an AGV (Automated Guided Vehicle), a dual-station baking furnace, a six-axis industrial robot, a vacuum induction melting and casting furnace, and a material unloading buffer area. The loading pallet is transported by the AGV from the mold shell drying area to the robot's material handling station. Two symmetrically distributed positioning pins are located on the bottom of the pallet, and two Omron E2E-X10ME1 inductive proximity switches, labeled SW1 and SW2, are installed on the corresponding workstation floor. When the pallet accurately sits on the positioning pin, SW1 and SW2 synchronously sense the metal pin and output a high-level signal to channels 0 and 1 of the PLC's DI module SM1221. The PLC simultaneously reads the state of the mechanical limit switch S3 on the safety fence gate. Only when all three conditions—SW1=1, SW2=1, and S3=1 (indicating the gate is closed)—are met simultaneously, is the "start-allowed" flag M10.0 set, triggering the subsequent process. If any switch is not triggered, M10.0 remains at 0, the robot is in standby mode, the HMI interface displays "Pallet not in place", and records the event timestamp T1 and the device status word W#16#0001.

[0069] Subsequently, the PLC outputs a high level through Q0.0 of the DO module SM1222, energizing the coil of the intermediate relay KA1. Its normally open contact closes, connecting the 24VDC power supply to the furnace door cylinder solenoid valve YV1. YV1 is a Festo MHJ9-MS type three-position five-way solenoid valve, controlling the action of a double-acting cylinder. The cylinder piston rod extends, driving the furnace door to rise along the vertical guide rail. A permanent magnet MAG is fixed to the top of the furnace door, and an SMC D-M9BL type reed limit switch LS_UP is installed at the corresponding position on the furnace frame. When the furnace door rises to its upper limit position, MAG approaches LS_UP, causing its internal contacts to close, inputting a high level to the PLC DI module. The PLC internally starts the TON timer T101, with a preset time of 5 seconds. If LS_UP=1 is not detected within 5 seconds, Q0.0 is reset, the power supply to YV1 is cut off, and the fault flag M20.1 is set. Simultaneously, the safety PLC module disables the robot's permission to enter the furnace entrance area. Only when LS_UP=1 is valid, and the PLC clears the interlock flag M30.0, can the robot execute the material handling path before entering the roasting furnace.

[0070] The robot base is fixed to a pre-embedded steel plate with anchor bolts, and an ATI QRC-50 quick-change disc female connector is installed on the end flange. Initially, a long clamping rod (1200mm in length) is used, with its male end inserted into the quick-change station interface. The PLC controls the YV2 (same model solenoid valve) via the DO signal to switch the air path, causing the pneumatic locking mechanism inside the quick-change disc to activate and lock the clamp. A two-finger parallel gripper is integrated at the end of the clamp. A SICK PBS-HD30 pressure transmitter PT1, with a range of 0–10 bar, outputs a 4–20mA signal connected to channel 0 of the AI ​​module SM1231. A Hall effect position sensor POS1 is built into the gripper body to detect whether the piston rod is in the middle stroke (i.e., not fully open or fully closed). The robot moves to the material handling coordinates P1 (X=1250.0, Y=-320.5, Z=850.2) calibrated by the laser tracker, and the Z-axis descends to Z=780.0, closing the gripper. The PLC continuously monitors whether the PT1 output value is within the 12–15mA (corresponding to 3.5–4.5bar) range for ≥2 seconds, while the POS1 output is at the intermediate level. Once both conditions are met, the gripping is considered successful. The robot then moves up to Z=1100 in LIN motion mode, then uses a CIRC trajectory to bypass the obstacle on the outer wall of the roasting furnace, enters the support hole P2 inside the furnace, releases the shell, and exits.

[0071] After the robot exits to the boundary of the non-interference zone defined by the laser scanner (electronic fence coordinate range X∈[1000,1500], Y∈[-500,-100]), the PLC sends a Modbus RTU write command to the Shimaden SRS13 temperature controller via the CM1241 RS485 module, writing the value 1250 (representing 1250℃) to register address 40001. The temperature controller then activates the SCR for power adjustment and heating. The three-phase main circuits L1, L2, and L3 pass through WEIGEL EQ72K current transformers CT1, CT2, and CT3 respectively, and the secondary side is connected to the same model current transmitters IT1, IT2, and IT3, outputting 4–20mA signals to AI module channels 1, 2, and 3. The PLC reads four analog signals (including thermocouple temperature signals) every second and calculates the effective value of the current in each phase. If any phase current is <8A (corresponding to 4mA+ threshold) and persists for 5 scan cycles, the heating fault flag M40.0 is set, the power supply to contactor KM1 coil is cut off, and the faulty phase is recorded. All data is packaged in the following structure format: {timestamp, order number ORD-20240501, device ID=BakeFurnace-02, T=1250.2℃, Ia=12.3A, Ib=12.1A, Ic=12.4A}, and uploaded to the SQL Server database table "ProcessData" via the OPC UA client.

[0072] After 60 minutes of heat preservation (set according to process requirements), the temperature controller outputs a dry contact signal to PLC DI channel 2 via hardwiring, indicating "heat preservation complete". The PLC then executes the furnace door opening procedure again. After the furnace door is fully open, the robot moves to the simulation mold test position P3, where a stainless steel simulation shell is fixed, with an appearance consistent with the real shell. The robot executes a simulated cycle: gripping → moving to the virtual casting position P4 → simulating placement at the positioning point → returning. During this process, the PLC monitors the quick-change plate body proximity switch SQ1 (confirming locking), the vacuum furnace door limit switch LS_VAC_DOOR (response time ≤ 2 seconds), and the medium-frequency furnace hydraulic cylinder travel switch LS_CLAMP (clamping plate in position). If SQ1 is not set within 100ms after gripping, or LS_VAC_DOOR does not respond to the opening status within 2 seconds after the PLC issues the door opening command, the process is interrupted, fault code ERR-205 is recorded, and the HMI displays a "quick-change not locked" or "vacuum furnace door response timeout" message.

[0073] After the formal hot shell transfer is initiated, the robot moves along the pre-planned trajectory at maximum speed. The TCP point starts from P2 inside the calcining furnace, passes through P5 (transition point), and arrives at the tray positioning point P6 in the vacuum furnace ingot mold chamber. The entire transfer process is recorded by a high-speed counter inside the PLC. After the hot shell transfer is completed, the robotic arm pulls the gripper out to the waiting position outside the vacuum furnace. The main PLC immediately sends a "ToolChange" command to the robot controller. The robot moves to the quick-change station, releases the long lever, grabs the short lever (800mm, 90kg load), and confirms the new gripper is locked in place via dual verification using SQ1 and air pressure PT1. It then moves to the casting removal waiting position. When casting is complete, the vacuum furnace PLC sets the "CastEnd" signal. The PLC reads the DB block data of the vacuum furnace PLC through ProfiNet: spindle height = 0.2 (tolerance ±1mm), vacuum degree = 105000Pa (≥10WPa), furnace door permission position = 1. After the three conditions are met, the PLC outputs Q1.0 to trigger the vacuum furnace door opening solenoid valve. After the door opening action is completed, the robot drives the short gripper to move synchronously to the casting removal position P7 and automatically performs the clamping of the casting, verifying again that PT1∈[12,15]mA and POS1=middle position. After success, based on the current occupancy matrix of the unloading pallet (obtained by querying the database after reading the pallet ID from the AGV RFID tag), the next placement coordinate P8_row3_col5 is dynamically calculated, the casting is placed in the designated grid, and the pallet occupancy status is updated.

[0074] Throughout the process, the PLC collects the position, speed, and TCP trajectory points of each axis from the robot controller at a 10ms cycle; records the furnace temperature, current, and furnace door opening / closing times at a 1s cycle; and captures the start and end times of quick-change actions and the I / O timing of fixture switching in an event-driven manner. All data is linked to order ORD-20240501 and stored in a database partition table. When quality inspection discovers surface microcracks in a casting from this order, the quality system retrieves the corresponding transfer data packet and analyzes that the interval from furnace exit to casting is 16.3 seconds, exceeding the 15-second threshold. The system automatically marks "transfer delay" as a potential factor and queries the ambient temperature sensor (installed next to the robot base) which records 32.5℃. Historical point cloud data from the laser scanner or historical video surveillance recordings show that a temporary toolbox is obstructing the path near P5 and waiting. The communication log shows a ProfiNet interaction delay of 85ms. These multi-source data together constitute a complete chain of evidence for quality anomalies, supporting decisions on process parameter optimization.

[0075] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

[0076] Exemplary apparatus In one exemplary embodiment of this specification, an apparatus 700 for transferring a mold shell in an investment casting process is also provided, such as... Figure 2 As shown, it includes: The first drive unit 701 is used to drive the industrial robot to transfer the cold shell to the calcining furnace after determining that the feeding tray is in place and the safety door is closed. The second drive unit 702 is used to drive the industrial robot to transfer the hot shell to the casting position of the vacuum casting furnace or the medium frequency turning furnace after the cold shell is baked into a hot shell, so as to cast the hot shell into a casting. The third drive unit 703 is used to drive the industrial robot to pick up the casting and transfer it to the unloading pallet for regular stacking after the casting is completed.

[0077] The shell transfer method and apparatus for investment casting process provided in this embodiment belongs to the same concept as the shell transfer method for investment casting process provided in the above embodiments of this application. It can execute the shell transfer method for investment casting process provided in any of the above embodiments of this application, and has the corresponding functional modules and beneficial effects for executing the shell transfer method for investment casting process. Technical details not described in detail in this embodiment can be found in the specific processing content of the shell transfer method for investment casting process provided in the above embodiments of this application, and will not be repeated here.

[0078] Exemplary device In one exemplary embodiment of this specification, an electronic device is also provided, such as Figure 3 As shown, the electronic device may include: a processor 310, a communication interface 320, a memory 330, and a communication bus 340, wherein the processor 310, the communication interface 320, and the memory 330 communicate with each other via the communication bus 340. The processor 310 can call logical instructions in the memory 330 to execute a method for transferring the mold shell in the investment casting process, the method including: After confirming that the feeding tray is in place and the safety door is closed, drive the industrial robot to transfer the cold shell to the calcining oven; After the cold shell is baked into a hot shell, the industrial robot is driven to transfer the hot shell to the casting position of the vacuum casting furnace or the medium frequency turning furnace to cast the hot shell into a casting. After casting is completed, the industrial robot is driven to pick up the casting and transfer it to the unloading pallet for regular stacking.

[0079] Furthermore, the logical instructions in the aforementioned memory 330 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, essentially, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0080] Exemplary computer program product and storage medium In addition to the methods, apparatus, and devices described above, the method for transferring the mold shell in the investment casting process provided in the embodiments of this specification can also be a computer program product, which includes computer program instructions that, when executed by a processor, cause the processor to perform the steps in the method for transferring the mold shell in the investment casting process according to various embodiments of this specification as described in the "Exemplary Methods" section above.

[0081] The computer program product can be written in any combination of one or more programming languages ​​to perform the operations of the embodiments of this specification. The programming languages ​​include object-oriented programming languages ​​such as Java and C++, as well as conventional procedural programming languages ​​such as the "C" language or similar programming languages.

[0082] Furthermore, embodiments of this specification also provide a computer-readable storage medium having a computer program stored thereon, the computer program being executed by a processor of the steps in the method for transferring the shell in the investment casting process according to various embodiments of this specification as described in the "Exemplary Methods" section above.

[0083] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this specification can include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0084] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0085] The embodiments described above are merely illustrative of several implementation methods outlined in this specification. While the descriptions are specific and detailed, they should not be construed as limiting the scope of the solutions provided in this specification. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this specification, and these all fall within the scope of protection of this specification. Therefore, the scope of protection for this patent should be determined by the appended claims.

Claims

1. A method for transferring the mold shell during investment casting, characterized in that, include: After confirming that the feeding tray is in place and the safety door is closed, drive the industrial robot to transfer the cold shell to the calcining oven; After the cold shell is baked into a hot shell, the industrial robot is driven to transfer the hot shell to the casting position of the vacuum casting furnace or the medium frequency turning furnace to cast the hot shell into a casting. After casting is completed, the industrial robot is driven to pick up the casting and transfer it to the unloading pallet for regular stacking.

2. The method for transferring the mold shell in the investment casting process according to claim 1, characterized in that, After confirming that the loading tray is in place and the safety door is closed, the process of driving the industrial robot to transfer the cold shell to the calcining furnace includes: Obtain the pallet arrival signal and determine whether the pallet is in place based on the pallet arrival signal; After confirming that the feeding tray is in place and the safety door is closed, control the opening of the roasting furnace door; Drive the industrial robot to the mold shell picking position, pick up the cold mold shell and transfer the cold mold shell to the designated position in the baking furnace according to the preset path.

3. The method for transferring the mold shell in the investment casting process according to claim 1, characterized in that, After the cold shell is baked into a hot shell, the industrial robot is driven to transfer the hot shell to the casting position of a vacuum casting furnace or a medium-frequency induction furnace to cast the hot shell into a casting, including: After the furnace door of the roasting furnace is closed and the industrial robot leaves the non-interference area, the target heating temperature command is sent to the roasting furnace temperature control system, and the furnace temperature and heating current data are collected in real time. In response to a signal indicating that the furnace exit conditions are met, the furnace door of the roasting furnace is controlled to open. The signal indicating that the furnace exit conditions are met is determined based on whether the temperature inside the roasting furnace has reached the set value and the holding time has been completed. The industrial robot is driven to pick up the hot shell and transfer it to the casting position of the vacuum casting furnace or the medium-frequency turning furnace.

4. The method for transferring the mold shell in the investment casting process according to claim 2, characterized in that, The process of obtaining the arrival signal of the loading pallet includes: Detect whether the two positioning proximity switches simultaneously output a high-level signal; If both positioning proximity switches output high-level signals, it is determined that the AGV has transported the loading pallet to the designated workstation and completed the positioning. If any positioning proximity switch does not output a high-level signal, the robot's movement will be paused and an alarm indicating that the tray is not in place will be triggered.

5. The method for transferring the mold shell in the investment casting process according to claim 3, characterized in that, Before driving the industrial robot to grip the hot shell and transfer it to the casting position of the vacuum casting furnace or medium-frequency induction furnace, the method further includes: Control the industrial robot to move to the simulated mold position and execute a simulated gripping-placing-removing cycle; In the simulation cycle, the accuracy of the control at each point in the shell transfer process, the locking status of the quick-change plate of the fixture, the opening and closing response time of the vacuum furnace door, and the positioning signal of the medium frequency tilting furnace clamp are verified. If all control points in the simulation cycle operate normally and the I / O signals are fed back normally within the preset time limit, then the formal hot shell transfer process will begin. If any control point activates, signals time out, or becomes abnormal, the process is interrupted and the corresponding fault point is indicated. At the same time, the action points of the transfer process can be adjusted through the human-machine interface.

6. The method for transferring the mold shell in the investment casting process according to claim 3, characterized in that, The process of sending a target heating temperature command to the calcining furnace temperature control system and collecting furnace temperature and heating current data in real time includes: The target temperature value is written to the roasting furnace temperature controller via the RS485 communication interface; The current of the three-phase heating circuit is collected by a current transformer and converted into a 4–20mA analog signal by a current transmitter and input to the PLC. If the current in any phase is lower than the set threshold and lasts for more than 5 seconds, it is determined that the heating element is open-circuited, heating is stopped and an alarm is triggered. The temperature and current values ​​collected every second are packaged and stored to generate a timestamped process data block.

7. The method for transferring the mold shell in the investment casting process according to claim 1, characterized in that, The process of driving an industrial robot to grip and transfer castings to a pallet for regular stacking includes: After casting is completed, the automatic fixture switching command is triggered based on the casting end signal fed back by the vacuum casting furnace or the medium frequency tilting furnace. Control the quick-change disc to release the long clamp rod and install the short clamp rod; Drive the robot to the casting removal position, clamp the casting, and then check whether the air pressure of the gripper is within the range of 3.5–4.5 bar and maintains it stably for 2 seconds; If the air pressure is within the specified range and the gripper position sensor shows that it is in the middle stroke, the gripping is considered successful and the stacking action is executed. If the air pressure is abnormal or the gripper is in the extreme position, it is determined to be an empty gripper, and the system will return to retry or issue an alarm.

8. The method for transferring the mold shell in the investment casting process according to claim 7, characterized in that, The rule-based stacking also includes fabric rule settings and optimization: Based on the specifications and quantity of the products to be processed, preset fabric specifications and rules are set or called in the loading tray, unloading tray and roasting oven; Based on the aforementioned fabric rules, the transfer path and placement position of the industrial robot within the roasting furnace are planned to shorten the overall transfer time and path, and the uniform temperature area within the roasting furnace is prioritized for shell placement.

9. The method for transferring the mold shell in the investment casting process according to claim 1, characterized in that, The method further includes synchronously recording equipment action time, furnace temperature curve, furnace door opening and closing status, fixture switching signals, and robot trajectory data during execution, and storing the data in a real-time database: When product quality is abnormal, retrieve the complete hot shell transfer data package of the corresponding production order; Analyze whether the time interval between the hot shell being removed from the furnace and the start of casting exceeds 15 seconds; Check the ambient temperature and whether there are any obstructions or delays in the robot's path during this time period; If the time interval exceeds the limit, the shell transfer process will be marked as a potential influencing factor.

10. The method for transferring the mold shell in the investment casting process according to claim 1, characterized in that, The control of opening the roasting furnace door includes: The PLC output signal is transmitted via a relay to energize the solenoid valve of the furnace door cylinder. Check whether the upper limit magnetic switch of the furnace door changes from normally open to closed; If no upper limit signal is received within 5 seconds, the power supply to the solenoid valve will be cut off and an alarm will be triggered to warn of furnace door jamming. Only after receiving the upper limit signal will the robot's motion interlock be released, allowing it to enter the interior area of ​​the roasting furnace.

11. A computer device, characterized in that, include: A memory and a processor are communicatively connected, the memory storing computer instructions, and the processor executing the computer instructions to perform the shell transfer method for the investment casting process as described in any one of claims 1 to 10.

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