Injection mold for shoe sole production

Abstract

The application relates to the technical field of injection molds, in particular to an injection mold for sole production, which comprises a mold main body structure and an auxiliary function assembly. The mold main body is composed of a movable mold plate and a fixed mold plate, is connected through a guide column and is fixed by a locking mechanism; the auxiliary function assembly comprises a flow channel control unit, a cooling unit and a demolding unit, and is respectively used for optimizing injection material distribution, improving cooling efficiency and reducing demolding stress. The flow channel control unit is provided with an adjusting piece and a pressure sensor, the cooling unit adopts a spiral flow guide vane and a circulating device, and the demolding unit realizes smooth demolding through a ejector rod and a spring. In addition, an exhaust groove and a wear-resistant coating are arranged on the inner wall of a mold cavity, so that the forming quality and service life are further improved. The application solves the problems of many forming defects, uneven cooling and difficult demolding in sole injection molding, significantly improves the production efficiency and product quality, and provides an innovative solution for the industry.

Description

Technical Field

[0001] This utility model belongs to the field of injection molding technology, specifically an injection mold for shoe sole production. Background Technology

[0002] In the injection molding process of shoe sole production, the design of the mold directly affects the molding quality, production efficiency, and mold lifespan. However, existing injection molds still have certain limitations in dealing with the complex shapes, uneven thicknesses, and efficient demolding requirements of shoe soles, making it difficult to fully meet the requirements of actual production.

[0003] Example: CN114055734B discloses an injection mold for automotive structural parts. It uses a moving mold to drive a core assembly to release the barbs, and a hydraulic device to separate the core assembly from the molding surface. Simultaneously, a hole-forming assembly moves synchronously with the core assembly to complete the spiral demolding. While this design effectively reduces demolding difficulty and improves the molding quality of connecting holes, its structural design is primarily aimed at structural parts with barbs and connecting holes, making it difficult to directly apply to products like shoe soles with complex surface textures and uneven thickness. Furthermore, this mold does not address optimization of runner control and cooling uniformity during shoe sole injection molding, potentially leading to more molding defects and longer production cycles in practical applications.

[0004] Furthermore, CN114932658B discloses an injection mold for products with high drops, which adopts a segmented core mold structure. A demolding mechanism sequentially drives each segment of the core mold to contract towards the center of the moving mold, thereby reducing the demolding area and demolding force. This solution improves demolding quality and product integrity to some extent, but its design focuses on solving the stress problem during demolding of high-drop barrel-shaped products. For shoe sole injection molding, due to the complex shape and varied curvature of the sole, directly applying this structure may lead to localized stress concentration, causing demolding deformation or damage. In addition, this mold does not consider key factors such as rapid cooling and optimized venting required for shoe sole injection molding. Therefore, in practical applications, it may result in problems such as long cooling times and residual air bubbles, affecting production efficiency and product quality.

[0005] In summary, while existing injection molds have achieved certain successes in molding and demolding specific structural components, they still fall short in meeting the demands of complex shapes, uniform cooling, efficient demolding, and high-quality molding in shoe sole production. Therefore, there is an urgent need to provide an injection mold specifically designed for shoe sole production to overcome these problems and improve overall manufacturing efficiency. Utility Model Content

[0006] The purpose of this invention is to solve the problems of numerous molding defects, uneven cooling, concentrated demolding stress, and low production efficiency in the production of shoe soles due to the complex shape, uneven thickness, and high efficiency of existing injection molds.

[0007] To achieve the aforementioned objectives and address the aforementioned problems, this utility model provides an injection mold for shoe sole production, comprising a main mold structure and auxiliary functional components. The main mold structure includes a moving mold plate and a fixed mold plate. When the moving and fixed mold plates are closed, they form a mold cavity for molding the shoe sole. The moving and fixed mold plates are connected by guide pillars and fixed by a locking mechanism. The auxiliary functional components include a flow channel control unit, a cooling unit, and a demolding unit. The flow channel control unit is located inside the fixed mold plate, the cooling unit is embedded in the moving and fixed mold plates, and the demolding unit is installed at the bottom of the fixed mold plate.

[0008] The flow channel control unit includes a manifold plate with several flow channels on its upper surface. The ends of these channels connect to the injection port. Adjustable plates are located on the side walls of the flow channels and are fixed to the inside of the manifold plate via threaded connections. A sealing ring is located at the end of each adjustable plate to prevent leakage of molten material. A heating element is located on the lower surface of the manifold plate and is connected to an external power source via wires to maintain the flowability of the injection molding material. A pressure sensor is located in the central area of ​​the manifold plate and is connected to an external controller via a signal line to monitor pressure changes during the injection molding process in real time.

[0009] As a preferred technical solution of this application, the cooling unit includes a cooling pipe and a coolant circulation device. The cooling pipe is embedded inside the moving and fixed mold plates and arranged along the outer contour of the mold cavity. An inlet and an outlet are respectively provided at both ends of the cooling pipe, and the inlet and outlet are connected to the coolant circulation device via hoses. The coolant circulation device includes a pump body and a cooler. The pump body is driven by a motor, and the cooler has heat dissipation fins inside, which are forcibly cooled by a fan. Spiral guide vanes are provided on the inner wall of the cooling pipe to enhance the fluidity and heat exchange efficiency of the coolant.

[0010] As a preferred technical solution of this application, the demolding unit includes a demolding template and an ejection mechanism. The demolding template is located at the bottom of the moving template. The upper surface of the demolding template has several ejector pin holes, and ejector pins are installed inside the ejector pin holes. The top ends of the ejector pins contact the bottom of the mold cavity. The lower ends of the ejector pins are connected to the demolding template via springs, and the preload of the springs can be adjusted by adjusting nuts. The ejection mechanism includes a cylinder and a transmission rod. The cylinder is fixed below the demolding template by a bracket. One end of the transmission rod is connected to the piston rod of the cylinder, and the other end is hinged to the bottom of the demolding template. The movement of the cylinder is controlled by a solenoid valve, which is connected to an external controller for automated operation.

[0011] As a preferred technical solution of this application, the inner wall of the mold cavity is provided with venting grooves. The width and depth of the venting grooves are optimized to ensure that gas can be quickly discharged during injection molding while preventing molten material from overflowing. A filter screen is provided at the end of the venting grooves to prevent impurities from entering the mold cavity. The surface of the mold cavity is coated with a wear-resistant coating composed of ceramic particles and a resin matrix to improve the service life of the mold.

[0012] As a preferred technical solution of this application, a sealing gasket is provided at the connection between the moving template and the fixed template. The sealing gasket is made of high-temperature resistant rubber material to prevent leakage of molten material during injection molding. A lubricating layer made of graphite material is provided on the surface of the guide post to reduce friction between the moving template and the fixed template. The locking mechanism includes a locking bolt, which is fixed to the side of the moving template by a threaded connection to achieve locking and unlocking.

[0013] As a preferred technical solution of this application, the signal output terminal of the pressure sensor is connected to the input terminal of an external controller, and the output terminal of the external controller is connected to the solenoid valve of the cylinder, forming a closed-loop control system. When the pressure sensor detects an abnormal injection pressure, the external controller automatically adjusts the cylinder's operating parameters to optimize the demolding process. The pump speed of the coolant circulation device can be adjusted by a frequency converter to adapt to the cooling requirements of different injection molding materials.

[0014] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0015] In this application, the problems of uneven runner distribution, low cooling efficiency, and concentrated demolding stress during shoe sole injection molding are solved by setting up a runner control unit, a cooling unit, and a demolding unit. The runner control unit achieves precise distribution of injection material through adjusting plates and pressure sensors, reducing the occurrence of molding defects. The cooling unit improves heat exchange efficiency and shortens cooling time through spiral guide vanes and a coolant circulation device, thereby increasing production efficiency. The demolding unit reduces the risk of damage to the shoe sole during demolding through the cooperation of ejector pins and springs, ensuring product integrity. In addition, the venting grooves and wear-resistant coating on the inner wall of the mold cavity further optimize the quality of the injection molding process and the service life of the mold.

[0016] In summary, this utility model, through structural optimization and functional integration of injection molds, comprehensively solves the needs for complex shapes, uneven thicknesses, and efficient demolding in shoe sole production, significantly improving molding quality, production efficiency, and mold lifespan, and providing an innovative solution for the shoe sole injection molding industry. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0018] Figure 2 This is a schematic diagram of the overall structure of the flow channel control unit.

[0019] Figure 3 This is a schematic diagram of the cooling unit.

[0020] Figure 4 This is a schematic diagram of the demolding unit.

[0021] Figure 5 This is a detailed view of the inner wall of the mold cavity.

[0022] The attached figures are labeled as follows:

[0023] 1. Moving template; 2. Fixed template; 3. Guide column; 4. Locking mechanism; 5. Diverter plate; 6. Diverter channel; 7. Adjusting plate; 8. Heating element; 9. Pressure sensor; 10. Cooling pipe; 11. Coolant circulation device; 12. Pump body; 13. Cooler; 14. Heat sink; 15. Template release; 16. Push rod; 17. Spring; 18. Cylinder; 19. Transmission rod; 20. Exhaust channel; 21. Filter screen; 22. Wear-resistant coating. Detailed Implementation

[0024] This utility model provides an injection mold for shoe sole production, and its specific implementation is described in detail with reference to the accompanying drawings. Figure 1 As shown, the injection mold includes a main mold structure and auxiliary functional components. The main mold structure consists of a moving mold plate 1 and a fixed mold plate 2. After the moving mold plate 1 and the fixed mold plate 2 are closed, they form a mold cavity for molding the shoe sole. The moving mold plate 1 and the fixed mold plate 2 are connected by guide posts 3. The two ends of the guide posts 3 are fixed in the corresponding mounting holes of the moving mold plate 1 and the fixed mold plate 2, respectively. The surface of the guide posts 3 is provided with a lubricating layer made of graphite material to reduce the friction between the moving mold plate 1 and the fixed mold plate 2. A sealing gasket is provided at the connection between the moving mold plate 1 and the fixed mold plate 2. The sealing gasket is made of high-temperature resistant rubber material to prevent leakage of molten material during injection molding. The locking mechanism 4 includes a locking bolt, which is fixed to the side of the moving mold plate 1 by a threaded connection.

[0025] The flow channel control unit is located inside the fixed template 2, such as Figure 2As shown, the flow control unit includes a manifold 5. The upper surface of the manifold 5 has several flow channels 6, the ends of which connect to the injection port. Adjusting plates 7 are located on the side walls of the flow channels 6 and are fixed to the inside of the manifold 5 via threaded connections. A sealing ring is provided at the end of the adjusting plate 7 to prevent leakage of molten material. A heating element 8 is located on the lower surface of the manifold 5 and is connected to an external power source via wires to maintain the flowability of the injection molding material. A pressure sensor 9 is located in the central area of ​​the manifold 5 and is connected to an external controller via a signal line. The external controller adjusts the injection parameters based on the pressure changes detected by the pressure sensor 9. The number and distribution of the flow channels 6 are designed according to the shape of the mold cavity and the flowability of the injection molding material to ensure that the molten material can uniformly fill the mold cavity.

[0026] The cooling unit is embedded in the moving template 1 and the fixed template 2, such as Figure 3 As shown, the cooling unit includes a cooling pipe 10 and a coolant circulation device 11. The cooling pipe 10 is embedded inside the moving mold plate 1 and the fixed mold plate 2, and is arranged along the outer contour of the mold cavity. The cooling pipe 10 has an inlet and an outlet at each end, which are connected to the coolant circulation device 11 via hoses. The coolant circulation device 11 includes a pump body 12 and a cooler 13. The pump body 12 is driven by a motor, and the cooler 13 has heat sinks 14 inside, which are cooled by a fan. The inner wall of the cooling pipe 10 has spiral guide vanes to enhance the fluidity and heat exchange efficiency of the coolant. The speed of the pump body 12 in the coolant circulation device 11 can be adjusted by a frequency converter to adapt to the cooling requirements of different injection molding materials, thereby shortening the cooling time and improving production efficiency.

[0027] The demolding unit is installed at the bottom of the fixed template 2, such as... Figure 4 As shown, the demolding unit includes a demolding template 15 and an ejection mechanism. The demolding template 15 is located at the bottom of the moving template 1. Several ejector pin holes are provided on the upper surface of the demolding template 15, and ejector pins 16 are installed inside the ejector pin holes. The top end of the ejector pin 16 contacts the bottom of the mold cavity. The lower end of the ejector pin 16 is connected to the demolding template 15 via a spring 17. The preload of the spring 17 can be adjusted by an adjusting nut to accommodate different sole thicknesses. The ejection mechanism includes a cylinder 18 and a transmission rod 19. The cylinder 18 is fixed below the demolding template 15 by a bracket. One end of the transmission rod 19 is connected to the piston rod of the cylinder 18, and the other end is hinged to the bottom of the demolding template 15. The movement of the cylinder 18 is controlled by a solenoid valve, which is connected to an external controller. The external controller adjusts the movement parameters of the cylinder 18 based on pressure changes detected by the pressure sensor 9, thereby achieving automated operation. After injection molding is completed, the cylinder 18 pushes the transmission rod 19 to move the demolding template 15 upwards, and the ejector pin 16 ejects the sole, completing the demolding process.

[0028] The inner wall of the mold cavity is provided with venting grooves 20, such as... Figure 5 As shown, the width and depth of the venting groove 20 are optimized to ensure rapid gas discharge during injection molding while preventing molten material overflow. A filter screen 21 is provided at the end of the venting groove 20 to prevent impurities from entering the mold cavity. The surface of the mold cavity is coated with a wear-resistant coating 22, which consists of ceramic particles and a resin matrix, to improve the mold's service life. The shape and size of the mold cavity are customized according to the design requirements of the shoe sole to ensure that the shape and thickness of the sole meet the product specifications.

[0029] In practical applications, the moving mold plate 1 and the fixed mold plate 2 are first aligned and closed using guide posts 3, and the locking mechanism 4 achieves rapid locking via locking bolts. The injection molding machine injects molten material into the flow channel 6 of the flow divider plate 5. The heating element 8 maintains the fluidity of the molten material, and the adjusting plate 7 adjusts the opening size of the flow channel 6 according to the injection pressure to ensure that the molten material is evenly distributed to the mold cavity. The pressure sensor 9 monitors the pressure changes during the injection process in real time and transmits the signal to an external controller, which adjusts the injection parameters based on the pressure data. After the molten material fills the mold cavity, the coolant circulation device 11 is activated. The coolant carries away heat through the cooling pipe 10, and the spiral guide vanes enhance the fluidity and heat exchange efficiency of the coolant, thereby shortening the cooling time. After the sole has cooled and formed, the cylinder 18 pushes the transmission rod 19 to move the demolding plate 15 upward, and the ejector rod 16 ejects the sole, completing the demolding process. The preload of the spring 17 can be adjusted according to the sole thickness to reduce the risk of damage to the sole during demolding. The venting groove 20 and the filter screen 21 ensure that gas is quickly discharged during the injection molding process and prevent impurities from entering the mold cavity, while the wear-resistant coating 22 improves the service life of the mold.

[0030] In the above embodiments, the connection relationships, positional relationships, and mutual cooperation relationships between the various components have been described in detail to ensure that those skilled in the art can implement the technical solution based on the contents of the specification.

[0031] To enable those skilled in the art to fully understand and implement this utility model, the following supplementary explanation of the specific implementation principle of this utility model is provided in conjunction with a specific application scenario.

[0032] First, the operator aligns the moving mold plate 1 and the fixed mold plate 2 using the guide post 3, ensuring that the sealing gaskets between them are tightly fitted. At this point, the locking mechanism 4 quickly locks in place, thus ensuring the stability of the mold closure. During this process, the graphite lubricating layer on the surface of the guide post 3 effectively reduces the friction between the moving mold plate 1 and the fixed mold plate 2, ensuring smooth mold opening and closing without any jamming.

[0033] Subsequently, the injection molding machine injects the molten material into the manifold 6 of the manifold 5. The manifold 6 is designed with optimized distribution according to the shape of the shoe sole mold cavity. The adjusting plates 7 on its sidewalls adjust the opening size through threaded connections to control the flow rate and velocity of the molten material. The heating element 8 maintains the fluidity of the molten material and avoids uneven injection due to temperature drops. The pressure sensor 9 monitors the pressure changes inside the manifold 5 in real time and transmits the signal to an external controller. When an abnormal pressure is detected, the external controller automatically adjusts the injection parameters to ensure that the molten material can uniformly fill the mold cavity and reduce the occurrence of molding defects.

[0034] After the molten material is filled, the cooling unit is immediately activated. The pump 12 in the coolant circulation device 11 drives the coolant through the cooling pipes 10, which are arranged along the outer contour of the mold cavity to ensure comprehensive cooling coverage. The spiral guide vanes on the inner wall of the cooling pipes 10 enhance the coolant's fluidity and heat exchange efficiency, while the heat sinks inside the cooler 13 force heat dissipation through a fan, further improving the cooling effect. By adjusting the speed of the pump 12 using a frequency converter, the cooling rate can be flexibly adjusted according to the characteristics of different injection molding materials, thereby shortening the cooling time and improving production efficiency.

[0035] After the sole cools and solidifies, the demolding unit begins operation. Upon receiving a signal from an external controller, cylinder 18 controls the piston rod via a solenoid valve to push the transmission rod 19, which in turn moves the demolding platen 15 upwards. The ejector rod 16 then pushes out the sole, completing the demolding process. The preload of spring 17 can be adjusted using an adjusting nut to accommodate different sole thicknesses, thereby reducing the risk of damage to the sole during demolding. Furthermore, because the contact position between the ejector rod 16 and the bottom of the mold cavity is precisely designed, it effectively disperses the demolding force, preventing deformation or damage caused by localized stress concentration.

[0036] During the injection molding process, the venting grooves 20 on the inner wall of the mold cavity play a crucial role. The width and depth of the venting grooves 20 are optimized to quickly expel gas during injection while preventing molten material from overflowing. The filter screen 21 at the end of the venting grooves 20 prevents impurities from entering the mold cavity, ensuring the cleanliness of the injection molding process. Furthermore, the wear-resistant coating 22 applied to the surface of the mold cavity, composed of ceramic particles and a resin matrix, significantly improves the mold's wear resistance and extends its service life.

[0037] In summary, the above steps describe in detail the operating principle of this invention in practical applications and the synergistic relationship between its components. Through optimized design of flow channel control, cooling efficiency, demolding process, venting, and wear resistance, this invention achieves the goals of precise molding of complex shapes, effective resolution of uneven thickness issues, and efficient demolding during shoe sole injection molding, providing reliable technical support for shoe sole production.

Claims

1. An injection mold for shoe sole production, characterized in that, The mold includes a main mold structure and auxiliary functional components. The main mold structure includes a moving mold plate (1) and a fixed mold plate (2). After the moving mold plate (1) and the fixed mold plate (2) are closed, they form a mold cavity for molding shoe soles. The moving mold plate (1) and the fixed mold plate (2) are connected by guide pillars (3) and fixed by locking mechanism (4). The auxiliary functional components include a flow channel control unit, a cooling unit and a demolding unit. The flow channel control unit is located inside the fixed mold plate (2). The cooling unit is embedded in the moving mold plate (1) and the fixed mold plate (2). The demolding unit is installed at the bottom of the fixed mold plate (2).

2. The injection mold for shoe sole production according to claim 1, characterized in that, The flow channel control unit includes a flow divider plate (5), the upper surface of the flow divider plate (5) is provided with a plurality of flow divider grooves (6), the end of the flow divider grooves (6) is connected to the injection port, the side wall of the flow divider grooves (6) is provided with an adjustment plate (7), the adjustment plate (7) is fixed inside the flow divider plate (5) by a threaded connection, the end of the adjustment plate (7) is provided with a sealing ring, the lower surface of the flow divider plate (5) is provided with a heating element (8), and the central area of ​​the flow divider plate (5) is provided with a pressure sensor (9).

3. The injection mold for shoe sole production according to claim 1, characterized in that, The cooling unit includes a cooling pipe (10) and a coolant circulation device (11). The cooling pipe (10) is embedded inside the moving template (1) and the fixed template (2) and arranged along the outer contour of the mold cavity. The two ends of the cooling pipe (10) are respectively provided with an inlet and an outlet. The inlet and outlet are connected to the coolant circulation device (11) through a hose. The coolant circulation device (11) includes a pump body (12) and a cooler (13). The cooler (13) is provided with heat sinks (14).

4. The injection mold for shoe sole production according to claim 1, characterized in that, The demolding unit includes a demolding template (15) and an ejection mechanism. The demolding template (15) is located at the bottom of the moving template (1). The upper surface of the demolding template (15) is provided with several ejector pin holes. Ejector pins (16) are installed inside the ejector pin holes. The top of the ejector pins (16) contacts the bottom of the mold cavity. The lower end of the ejector pins (16) is connected to the demolding template (15) through a spring (17). The ejection mechanism includes a cylinder (18) and a transmission rod (19). The cylinder (18) is fixed below the demolding template (15) by a bracket. One end of the transmission rod (19) is connected to the piston rod of the cylinder (18), and the other end is hinged to the bottom of the demolding template (15).

5. An injection mold for shoe sole production according to claim 1, characterized in that, The inner wall of the mold cavity is provided with an exhaust groove (20), and the end of the exhaust groove (20) is provided with a filter screen (21). The surface of the mold cavity is coated with a wear-resistant coating (22), which is composed of ceramic particles and resin matrix.

6. The injection mold for shoe sole production according to claim 1, characterized in that, The connection between the moving template (1) and the fixed template (2) is provided with a sealing gasket, which is made of high temperature resistant rubber material. The surface of the guide column (3) is provided with a lubricating layer, which is made of graphite material. The locking mechanism (4) includes a locking bolt, which is fixed to the side of the moving template (1) by a threaded connection.

7. The injection mold for shoe sole production according to claim 3, characterized in that, The inner wall of the cooling pipe (10) is provided with spiral guide vanes, and the speed of the pump body (12) of the coolant circulation device (11) is adjusted by a frequency converter.

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