Closed-loop control forming structure based on digital twinning technology

Abstract

The invention relates to the technical field of mold forming, in particular to a closed-loop control forming structure based on the digital twinning technology, which comprises a movable mold base, a fixed mold base, a guide column and a guide sleeve, the guide column is fixed on the fixed mold base and extends along the mold closing direction, the guide sleeve is arranged on the movable mold base and is in sliding fit with the guide column, an annular strain groove is formed in the outer wall of the guide column, and the annular strain groove is communicated with the fixed mold base. A strain gauge group which is arranged in the circumferential direction is adhered to the strain groove area, the strain gauge group is connected with a signal transmission module through a lead, and the signal transmission module is installed in the movable die holder and is in wireless communication with an external digital twinning control system. According to the closed-loop control forming structure based on the digital twinning technology, the stress state of the guide column is monitored in real time, the mold closing precision is improved, the service life of the mold is prolonged, meanwhile, the synchronism of a digital twinning model and a physical mold is enhanced, and the reliability of closed-loop control is effectively guaranteed.

Description

Technical Field

[0001] This invention relates to the field of mold forming technology, specifically to a closed-loop control forming structure based on digital twin technology. Background Technology

[0002] With the rapid development of modern manufacturing, precision molding technology is increasingly widely used in the automotive, electronics, and home appliance industries. As a core piece of equipment in the molding process, the mold's structural performance directly affects the product's dimensional accuracy, surface quality, and production efficiency. In recent years, digital twin technology has been gradually introduced into the manufacturing process, providing a new technological approach for monitoring and optimizing the molding process by constructing a real-time mapping relationship between physical molds and virtual models.

[0003] Currently, in traditional mold forming structures, the mold closing and positioning between the moving mold and the fixed mold mainly relies on the mechanical cooperation of guide pillars and guide sleeves. Although this structure is simple and reliable, during long-term high-frequency operation, due to the lack of a real-time feedback mechanism for the stress state and positional deviation of the guide pillars, the guide pillars are prone to slight deformation or displacement due to local stress concentration or foreign object interference. This physical deformation cannot be detected and compensated by the system in time, resulting in deviations between the virtual model and the actual mold state. This leads to problems such as improper mold closing, flash on the product, and even mold damage, affecting molding accuracy and mold life, and also weakening the closed-loop effectiveness of the digital twin system in actual control. Summary of the Invention

[0004] The purpose of this invention is to provide a closed-loop control molding structure based on digital twin technology to solve the problems mentioned in the background art, such as the inability to detect the force offset or deformation of the mold guide pillars in real time during long-term operation, which leads to decreased mold closing accuracy, product defects, and the desynchronization between the digital twin model and the actual state.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a closed-loop control molding structure based on digital twin technology, comprising a moving mold base, a fixed mold base, a guide post, and a guide sleeve, characterized in that: the guide post is fixed on the fixed mold base and extends along the mold closing direction; the guide sleeve is disposed on the moving mold base and slides in cooperation with the guide post; the outer wall of the guide post is provided with an annular strain groove; a group of circumferentially arranged strain gauges is attached to the strain groove area; the group of strain gauges is connected to a signal transmission module through leads; the signal transmission module is installed inside the moving mold base and wirelessly communicates with an external digital twin control system.

[0006] Preferably, the strain groove is an annular groove with a U-shaped cross-section, a depth of 1 / 3 to 2 / 5 of the guide post wall thickness, and is located 10-15 mm below the free end of the guide post.

[0007] Preferably, the strain gauge group consists of four miniature resistance strain gauges, which are circumferentially attached to the side wall of the strain groove at equal angles of 90 degrees.

[0008] Preferably, the inner surface of the guide sleeve is provided with a continuously spiraling oil groove, and the oil groove extends axially from the top of the guide sleeve to the middle and is connected to the external lubrication system.

[0009] Preferably, the signal transmission module is embedded in a sealed cavity on the side of the moving mold base, and the sealed cavity is provided with a waterproof and breathable membrane and a metal shield.

[0010] Preferably, the guide post has a stepped shaft structure near the fixed end. The stepped shaft is press-fitted with the stepped hole on the fixed mold base by a nut, and the stepped shaft section of the guide post is provided with an anti-rotation flat key, which is embedded in the corresponding keyway in the stepped hole of the fixed mold base.

[0011] Preferably, the lead wire is a high-temperature shielded wire with a corrugated protective sleeve on its outer layer. One end of the lead wire is soldered to the terminal of the strain gauge assembly, and the other end is connected to the terminal of the signal transmission module.

[0012] Preferably, the outer ring of the guide sleeve is provided with a positioning boss, which is embedded in the mounting hole on the moving mold base and fixed by a locking screw.

[0013] Preferably, the free end of the guide post is provided with an inlet cone angle, the inlet cone angle being 15°-20°.

[0014] Preferably, the moving mold base is provided with an annular sensing groove at the position corresponding to the guide post, and a displacement sensor is installed in the annular sensing groove.

[0015] Compared with existing technologies, the beneficial effects of this invention are as follows: This closed-loop control molding structure based on digital twin technology enables real-time monitoring of the stress state of the guide pillars, improving mold closing accuracy and mold lifespan. Simultaneously, it enhances the synchronization between the digital twin model and the physical mold, effectively ensuring the reliability of closed-loop control. This structure, by setting annular strain grooves on the guide pillars and coordinating with circumferentially arranged strain gauges, achieves precise sensing of minute deformations of the guide pillars. Furthermore, by transmitting signals via leads to a signal transmission module integrated into the moving mold base, it achieves real-time wireless feedback of state data. Combined with the sliding fit structure of the guide pillars and guide sleeves, the guiding components possess both mechanical positioning and state feedback functions, thereby significantly improving the intelligent sensing capability and closed-loop control accuracy of the molding system without altering the basic mold structure. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a closed-loop control molding structure based on digital twin technology according to the present invention.

[0017] Figure 2 This is a schematic diagram of the connection structure between the guide pillar, the moving mold base, and the fixed mold base of a closed-loop control molding structure based on digital twin technology according to the present invention.

[0018] Figure 3 This is a schematic diagram of the top structure at the connection between the guide post and the moving mold base of a closed-loop control molding structure based on digital twin technology according to the present invention.

[0019] Figure 4 This is a schematic diagram of the bottom structure at the connection between the guide post and the moving mold base of a closed-loop control molding structure based on digital twin technology according to the present invention.

[0020] Figure 5 This is a schematic diagram of the connection structure between the strain gauge assembly and the guide post in a closed-loop control molding structure based on digital twin technology according to the present invention.

[0021] In the diagram: 1. Moving mold base; 2. Fixed mold base; 3. Guide post; 4. Guide sleeve; 5. Strain gauge groove; 6. Strain gauge assembly; 7. Signal transmission module; 8. Oil groove; 9. Nut; 10. Anti-rotation key; 11. Bellows protective sleeve; 12. Positioning boss; 13. Locking screw; 14. Annular sensing groove; 15. Displacement sensor. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Please see Figure 1-5This invention provides a technical solution: a closed-loop control molding structure based on digital twin technology, including a moving mold base 1, a fixed mold base 2, a guide post 3, and a guide sleeve 4. The guide post 3 is fixed on the fixed mold base 2 and extends along the mold closing direction. The guide sleeve 4 is disposed on the moving mold base 1 and slides with the guide post 3. The outer wall of the guide post 3 is provided with an annular strain groove 5. A circumferentially arranged strain gauge group 6 is attached to the area of ​​the strain groove 5. The strain gauge group 6 is connected to a signal transmission module 7 through a lead wire. The signal transmission module 7 is installed inside the moving mold base 1 and communicates wirelessly with an external digital twin control system. In this structure, when the moving mold base 1 and the fixed mold base 2 perform mold closing movements, the guide post 3 slides in the guide sleeve 4 to achieve guidance and positioning. If the guide post 3 undergoes slight bending or displacement due to uneven force, foreign object entry, or long-term wear, the structure will be able to achieve this. The annular strain groove 5 on its surface will generate local strain. The circumferentially arranged strain gauge group 6 can sense this deformation in real time and convert it into an electrical signal. This signal is transmitted through a lead wire to the signal transmission module 7 installed inside the moving mold base 1. The signal transmission module 7 wirelessly sends the data to the external digital twin control system, so that the virtual model can reflect the actual stress state of the guide post 3 in real time. The system determines whether to adjust the mold closing parameters or issue an early warning based on this, thereby realizing the dynamic synchronization of the physical mold and the digital model in the state of key guiding components. This effectively solves the problems in the existing technology of improper mold closing, product flash, mold damage, and failure of closed-loop control of digital twin system caused by the inability to sense the deformation of the guide post. The strain groove 5 is an annular groove with a U-shaped cross-section and a depth of The strain gauge 5 has a diameter of 1 / 3 to 2 / 5 of the wall thickness of the guide post 3 and is located 10-15 mm below the free end of the guide post 3. When the guide post 3 deforms under lateral force, the annular strain gauge 5, due to its geometric shape, weakens the local stiffness, making the stress concentration effect more pronounced. This facilitates the strain gauge group 6 in accurately capturing micro-strain signals. Simultaneously, its location below the free end is in the area most prone to bending deformation during mold closing, accurately reflecting the actual stress state of the guide post 3 and ensuring the representativeness and timeliness of the feedback data. This provides an accurate basis for the closed-loop control of the digital twin system. The strain gauge group 6 consists of four miniature resistance strain gauges, circumferentially attached at 90-degree angles to the sidewall of the strain gauge 5, forming a full-bridge circuit connection. This structure allows the strain gauge group 6 to comprehensively sense... The bending deformation of the guide post 3 in any direction, when the guide post 3 deviates, generates a differential signal due to the change in resistance between the tension and compression sides of the circumferentially distributed strain gauges. This signal is output through a full-bridge circuit with high sensitivity, effectively eliminating temperature drift interference and ensuring the accuracy and stability of strain measurement. This provides reliable data support for determining the direction and degree of off-center loading of the guide post 3. The inner surface of the guide sleeve 4 is provided with a continuously spiraling oil groove 8, which extends axially from the top of the guide sleeve 4 to the middle and is connected to the external lubrication system. During the mold closing process, this structure allows the lubricating medium to be evenly distributed along the spiraling oil groove 8 on the contact surface between the guide post 3 and the guide sleeve 4, forming a continuous oil film. This effectively reduces frictional resistance and local wear, and prevents the guide post 3 from becoming eccentric or stuck due to uneven lubrication.To ensure the smoothness of the guiding motion, the signal transmission module 7 is embedded in a sealed cavity on the side of the moving mold base 1. This sealed cavity is equipped with a waterproof and breathable membrane and a metal shield. This structure effectively isolates the signal transmission module 7 from the effects of high temperature, high pressure, moisture, and electromagnetic interference during injection molding, ensuring its long-term stable operation under harsh conditions and preventing signal loss or distortion. The guide post 3 has a stepped shaft structure near its fixed end. This stepped shaft is pressed against the stepped hole on the fixed mold base 2 by a nut 9. The stepped shaft section of the guide post 3 is equipped with an anti-rotation key 10, which is embedded in the corresponding keyway in the stepped hole of the fixed mold base 2. This structure achieves reliable axial fixation of the guide post 3 on the fixed mold base 2 through the pressing fit between the stepped shaft and the nut 9, while utilizing the anti-rotation key 10... The guide post 3 is designed to restrict circumferential rotation, preventing it from rotating due to vibration or lateral force during frequent sliding. This ensures the spatial orientation of the strain gauge 5 and strain gauge assembly 6 remains stable, avoiding signal distortion caused by sensor position deviation and guaranteeing the consistency and accuracy of feedback data. The lead wire is a high-temperature shielded wire, and the outer wall of the guide post 3 has a hidden groove that matches the lead wire structure. It is covered by a corrugated protective sleeve 11. One end of the lead wire is soldered to the terminal of the strain gauge assembly 6, and the other end is connected to the terminal of the signal transmission module 7. This structure ensures signal transmission stability and effectively suppresses electromagnetic interference in the high-temperature, high-vibration working environment of the mold through the high-temperature shielded wire. Simultaneously, the corrugated protective sleeve 11 provides mechanical protection for the lead wire, preventing damage from repeated vibrations. Movement or external compression can cause wire breakage or short circuits. To ensure the safe, continuous, and lossless transmission of the weak electrical signals collected by the strain gauge group 6 to the signal transmission module 7, maintaining the long-term reliable operation of the entire monitoring link, the outer ring of the guide sleeve 4 is provided with a positioning boss 12. The positioning boss 12 is embedded in the mounting hole on the moving mold base 1 and fixed by the locking screw 13. This structure achieves precise axial and circumferential positioning of the guide sleeve 4 on the moving mold base 1 through the positioning boss 12, preventing it from loosening or rotating during use. At the same time, the locking screw 13 provides reliable clamping force to ensure that the guide sleeve 4 remains stable under high-frequency mold closing impact, maintaining the fitting accuracy between the guide post 3 and the guide sleeve 4. The free end of the guide post 3 is provided with an inlet cone angle, which is 15°-20°. The structure guides the guide post 3 to smoothly insert into the guide sleeve 4 during the initial mold closing stage, effectively compensating for minor positional deviations between the moving and fixed molds, reducing initial off-center load impacts, preventing collisions or scratches between the end of the guide post 3 and the edge of the guide sleeve 4, protecting the strain gauge 5 and strain gauge assembly 6 from damage by sudden lateral forces, and ensuring the guiding system smoothly enters the working state, improving the smoothness of mold closing and repeatability. An annular sensing groove 14 is provided on the moving mold base 1 at the position corresponding to the guide post 3. The annular sensing groove 14 is located at the bottom of the connection between the moving mold base 1 and the guide post 3. A displacement sensor 15 is installed inside the annular sensing groove 14. This structure monitors the insertion depth and movement trajectory of the guide post 3 in real time through the displacement sensor 15. Combined with the force data of the strain gauge assembly 6, it can comprehensively determine whether the mold closing process is normal.Timely detection of faults such as incomplete mold closing, abnormal ejection, or foreign objects inside the mold further enhances the digital twin system's perception of the actual state, strengthening the comprehensiveness and security of closed-loop control.

[0024] Working principle: When using this closed-loop control molding structure based on digital twin technology, the moving mold base 1 first moves closer to the fixed mold base 2 under the action of the drive device. The guide post 3's guide cone angle guides it smoothly into the inner hole of the guide sleeve 4. As the mold closes, the guide post 3 slides within the guide sleeve 4 to complete the guiding and positioning. The lubrication system injects lubricating oil and connects it with the continuous spiral oil groove 8 on the inner surface of the guide sleeve 4, so that the lubricating oil is evenly distributed on the mating surface. If the guide post 3 undergoes slight bending or displacement during the mold closing process, local strain is generated in the annular strain groove 5 area on its outer wall, causing it to adhere to the groove wall. The strain gauge group 6 senses deformation in real time and converts it into an electrical signal. This signal is transmitted to the signal transmission module 7 after being protected by a high-temperature shielded wire and a corrugated sleeve 11. The signal transmission module 7 wirelessly sends the data to the external digital twin control system. At the same time, the displacement sensor 15 on the moving mold base 1 detects the insertion depth of the guide post 3 and uploads it synchronously. The control system judges the mold closing state based on the received strain and displacement information. After completing one molding cycle, the moving mold base 1 retracts and the guide post 3 exits from the guide sleeve 4, preparing for the next cycle, thus completing a series of tasks.

[0025] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A closed-loop control molding structure based on digital twin technology, comprising a moving mold base (1), a fixed mold base (2), guide pillars (3), and guide sleeves (4), characterized in that: The guide post (3) is fixed on the fixed mold base (2) and extends along the mold closing direction. The guide sleeve (4) is set on the moving mold base (1) and slides with the guide post (3). The outer wall of the guide post (3) is provided with an annular strain groove (5). A circumferentially arranged strain gauge group (6) is pasted in the area of ​​the strain groove (5). The strain gauge group (6) is connected to the signal transmission module (7) through the lead wire. The signal transmission module (7) is installed inside the moving mold base (1) and communicates wirelessly with the external digital twin control system.

2. The closed-loop control molding structure based on digital twin technology according to claim 1, characterized in that: The strain groove (5) is an annular groove with a U-shaped cross section. Its depth is 1 / 3 to 2 / 5 of the wall thickness of the guide post (3) and it is located 10-15 mm below the free end of the guide post (3).

3. The closed-loop control molding structure based on digital twin technology according to claim 1, characterized in that: The strain gauge group (6) consists of four miniature resistance strain gauges, which are circumferentially attached to the side wall of the strain groove (5) at equal angles of 90 degrees.

4. The closed-loop control molding structure based on digital twin technology according to claim 1, characterized in that: The inner surface of the guide sleeve (4) is provided with a continuously spiraling oil groove (8), and the oil groove (8) extends axially from the top of the guide sleeve (4) to the middle and is connected to the external lubrication system.

5. The closed-loop control molding structure based on digital twin technology according to claim 1, characterized in that: The signal transmission module (7) is embedded in a sealed cavity on the side of the moving mold base (1), and the sealed cavity is provided with a waterproof and breathable membrane and a metal shield.

6. The closed-loop control molding structure based on digital twin technology according to claim 1, characterized in that: The guide post (3) is provided with a stepped shaft structure near the fixed end. The stepped shaft is pressed and fitted with the stepped hole on the fixed mold base (2) by a nut (9). The stepped shaft section of the guide post (3) is provided with an anti-rotation flat key (10). The anti-rotation flat key (10) is embedded in the corresponding keyway in the stepped hole of the fixed mold base (2).

7. The closed-loop control molding structure based on digital twin technology according to claim 1, characterized in that: The lead wire is a high-temperature shielded wire, and its outer layer is covered with a corrugated tube protective sleeve (11). One end of the lead wire is welded to the terminal of the strain gauge group (6), and the other end is connected to the terminal of the signal transmission module (7).

8. The closed-loop control molding structure based on digital twin technology according to claim 1, characterized in that: The outer ring of the guide sleeve (4) is provided with a positioning boss (12), which is embedded in the mounting hole on the moving mold base (1) and fixed by a locking screw (13).

9. The closed-loop control molding structure based on digital twin technology according to claim 1, characterized in that: The free end of the guide post (3) is provided with an inlet cone angle, which is 15°-20°.

10. The closed-loop control molding structure based on digital twin technology according to claim 1, characterized in that: The moving mold base (1) is provided with an annular sensing groove (14) at the position corresponding to the guide post (3), and a displacement sensor (15) is installed in the annular sensing groove (14).

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