A rotary core mold

Abstract

This invention proposes a rotating core-pulling mold for injection molding of bent pipes, comprising an upper mold and a lower mold, with a molding cavity between them. An arc-shaped core is located within the molding cavity. A rotating block is fixed to one end of the core, positioned by a positioning groove in the upper mold, and the core is slidably oriented by an arc-shaped rotating groove in the lower mold. The rotating groove is coaxial with the core. A coaxial gear is fixed to the rotating block within the lower mold, and a drive device in the lower mold drives the gear to rotate. The other end of the core abuts against a cylindrical core. A receiving cavity is provided between the upper and lower molds, and a slider is fixed to the other end of the core. The slider is positioned by a positioning groove in the upper mold, and the slider is slidably oriented by a groove in the lower mold. The upper mold has a slanted ejector rod, and the slider has a corresponding insertion groove. After injection molding, the upper mold moves upward, causing the slider and core to linearly pull the core. The drive device drives the gear, causing the rotating block and core to rotate and pull the core. This mold has a simple structure, is easy and efficient to demold, and the core fits the inner cavity of the bent pipe, resulting in good molding quality.

Description

Technical Field

[0001] This invention relates to the field of injection mold technology, and more specifically to a rotating core-pulling mold. Background Technology

[0002] In the injection molding process of tubular plastic products, core pulling and demolding is an indispensable key process, the purpose of which is to smoothly separate the product wrapped on the core after molding from the mold.

[0003] Depending on the structural differences of tubular products, there are significant differences in the core-pulling and demolding methods: For straight tube products with simple structures, since their axis is a straight line, the core-pulling operation can be carried out directly using a linear motion method. This method has the advantages of simple structure, convenient operation, and high efficiency.

[0004] However, with the diversified needs of industrial production, the application of bent tubular products is becoming increasingly widespread. Because the axis of such products is curved, the difficulty of core pulling and demolding operations is significantly increased. The traditional straight core pulling method is no longer applicable. If straight core pulling is forcibly used, it will interfere with the inner wall of the bent tube, causing scratches, deformation or even damage to the product. It may also cause the mold core to jam or wear, affecting the service life of the mold.

[0005] To solve the problem of core pulling and demolding in bent pipe products, a variety of solutions have been proposed in the existing technology. One of the more widely used solutions is to design the core as a multi-part split structure. After injection molding, each split core is pulled out in a straight line, and the core is separated from the bent pipe product by pulling the core in steps.

[0006] For example, Chinese patent application CN108527791A discloses a tube bending core pulling mechanism, which uses multiple split cores in conjunction with a linear drive structure. By controlling the linear movement of each split core in stages, the core pulling and demolding of the bent tube product is completed.

[0007] Although the above-mentioned multi-piece split-type straight core-pulling solution can solve the demolding problem of bent pipe products to a certain extent, it still has shortcomings in practical application: On the one hand, the core-pulling process requires controlling each separate core to complete the linear core-pulling action in sequence step by step. The steps are cumbersome and the operation is complicated, which not only increases the difficulty of equipment control, but also significantly prolongs the core-pulling cycle and reduces the overall production efficiency. On the other hand, there are inevitably gaps between multiple separate cores. These gaps will form splicing marks on the inner wall of the product, affecting the product's molding accuracy and surface quality. This defect is particularly prominent for bent tube products that require high inner wall smoothness, and may even cause the product to fail to meet the usage requirements. Summary of the Invention

[0008] In view of the problems pointed out in the background art, the present invention proposes a rotating core-pulling mold to solve the above-mentioned technical problems.

[0009] The technical solution of this invention is implemented as follows: A rotating core-pulling mold includes an upper mold and a lower mold, with a forming cavity provided between the upper and lower molds. The molding cavity is provided with an arc-shaped core. One end of the core is fixedly connected to a rotating block. The upper mold is provided with a positioning groove that is connected to the upper side of the rotating block. The lower mold is provided with a rotating groove that is slidably connected to the lower side of the rotating block. The rotating groove is arc-shaped, and the central axis of the rotating groove is coaxial with the central axis of the core. The lower mold is equipped with a rotatable gear, the central axis of which is coaxial with the central axis of the rotating groove. The rotating block is fixedly connected to the gear, and the lower mold is equipped with a drive device to drive the gear to rotate. The other end of the core one is provided with a core two that abuts against it. The core two is cylindrical, and a receiving cavity connected to the core two is formed between the upper mold and the lower mold. The end of the second core away from the first core is fixedly connected to a slider. The upper mold is provided with a positioning groove 2 that is adapted to and connected to the upper side of the slider. The lower mold is provided with a sliding groove that is slidably connected to the lower side of the slider. The upper mold is equipped with an inclined ejector rod, and the slider is equipped with an insertion slot that corresponds to the inclined ejector rod.

[0010] The invention is further configured such that the upper side of the lower mold is provided with a mounting groove 1, the lower module is adapted to be connected in the mounting groove 1, and the bottom of the mounting groove 1 is provided with a mounting groove 2 adapted to be connected to the gear; a rotating groove is provided on the lower module, the lower side of the rotating block extends downward to form a linkage part, the gear is provided with a linkage groove connected to the linkage part, and the lower end face of the linkage part abuts and cooperates with the bottom surface of the mounting groove 2.

[0011] The invention is further configured such that the slide groove extends through one side of the lower mold, and one side of the lower mold is detachably connected to an anti-detachment component to prevent the slider from disengaging from the slide groove.

[0012] The invention is further configured such that a movable ejector plate is connected to the lower side of the lower mold, and a plurality of ejector pins are connected to the ejector plate. Some of the ejector pins pass through the gear, and the gear is provided with a through groove corresponding to the ejector pin. The through groove is arranged along the circumference of the gear.

[0013] The present invention is further configured such that a limiting inclined surface is formed on the upper side of the rotating block, and the limiting inclined surface cooperates with the upper mold to prevent the rotating block from rotating away from the core.

[0014] The present invention is further configured such that a limiting inclined surface two is formed on the upper side of the slider, and the limiting inclined surface two cooperates with the upper mold to prevent the slider from sliding away from the core one.

[0015] The present invention is further configured such that the driving device includes a rack and a driving cylinder, the lower mold is provided with a telescopic groove extending through both sides therethrough, the telescopic groove is connected to the mounting groove, the rack is slidably connected in the telescopic groove, the rack meshes with the gear, and the driving cylinder is fixed on the outer side wall of the lower mold, the driving cylinder is used to drive the rack to reciprocate.

[0016] The invention is further configured such that the lower module is provided with an injection groove communicating with the molding cavity, and the upper mold is provided with an injection hole communicating with the injection groove, the injection hole penetrating the upper side of the upper mold.

[0017] The present invention is further configured such that the slider and the second core are integrally formed, and the rotating block, the first core, and the linkage are integrally formed; the mating surfaces of the second core and the first core are respectively provided with corresponding connecting holes one and two; the outer wall of the slider is provided with an air outlet, and the interior of the slider and the second core is provided with a cooling channel connecting the first hole and the air outlet; the lower end face of the linkage is provided with an air inlet, and the interior of the rotating block, the first core, and the linkage is provided with a cooling channel connecting the second hole and the air inlet; the bottom surface of the mounting groove two is provided with holes three and four corresponding to the air inlet, and holes three and four are located in the rotation direction of the linkage; the outer wall of the lower mold is provided with a main air hole, and the interior of the lower mold is provided with a channel connecting the main air hole and holes three and four.

[0018] The invention is further configured such that the lower mold is provided with two guide rails spaced apart, and the opposing surfaces of the guide rails are respectively provided with sliding grooves, and the two sides of the slider are respectively provided with sliding parts that are slidably connected to the sliding grooves; the anti-detachment component is long and strip-shaped, and the two ends of the anti-detachment component are fixedly connected to the two guide rails by bolts.

[0019] By adopting the above technical solution, the beneficial effects of the present invention are as follows: The rotating core-pulling mold provided by this invention can be used for injection molding of bent pipes. After injection molding is completed, the upper mold moves upward, simultaneously driving the slider and the second core to move linearly for core pulling and demolding; the driving device then drives the gear to rotate, and the gear drives the rotating block and the first core to rotate through the linkage part for rotational core pulling and demolding.

[0020] The arc-shaped core fits the inner cavity of the bent tube. After injection molding, the core can rotate and be pulled out from the inside of the bent tube in one go. Its structure is simple, the demolding operation is convenient, the demolding efficiency is high, and the product molding quality is good.

[0021] Core 1 and Core 2 are equipped with interconnected cooling channels. After injection molding is completed, cold air enters the cooling channels to help the product cool and solidify quickly. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention 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 some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the structure of the injection-molded product of the present invention.

[0024] Figure 2 This is a schematic diagram of the structure of the mold of the present invention.

[0025] Figure 3 This is an exploded view of the present invention.

[0026] Figure 4 This is a schematic diagram of the structure of the lower side of the upper mold of the present invention.

[0027] Figure 5 This is a schematic diagram of the upper side of the lower mold of the present invention.

[0028] Figure 6 This is a structural diagram showing the disassembled internal parts of the lower mold of the present invention.

[0029] Figure 7 This is a schematic diagram of the structure of the gear arrangement in the lower mold of the present invention.

[0030] Figure 8 This is a schematic diagram of the lower mold, gear, and drive device of the present invention.

[0031] Figure 9 This is a schematic diagram of the lower side surface of the lower mold of the present invention.

[0032] Figure 10 This is a structural schematic diagram of the lower module and core two of the present invention.

[0033] Figure 11 This is an exploded view of the lower module and core two of the present invention.

[0034] Figure 12 This is a schematic diagram of the gear and rack assembly structure of the present invention.

[0035] Figure 13 This is a structural schematic diagram of the lower module and core of the present invention.

[0036] Figure 14 This is an exploded view of the lower module and core of the present invention.

[0037] Figure 15 This is a schematic diagram of the structure of the first core of the present invention. Figure 1 .

[0038] Figure 16 This is a schematic diagram of the structure of the first core of the present invention. Figure 2 .

[0039] Figure 17 This is a schematic diagram of the structure of core two of the present invention. Figure 1 .

[0040] Figure 18 This is a schematic diagram of the structure of core two of the present invention. Figure 2 .

[0041] The following are the labels in the attached diagram: Upper mold 1, Lower mold 2, Molding cavity 3, Core 1 4, Rotating block 5, Positioning groove 1 6, Rotating groove 7, Gear 8, Core 2 9, Receiving cavity 10, Slider 11, Positioning groove 2 12, Slide groove 13, Angled ejector rod 14, Insertion groove 15, Mounting groove 16, Lower module 17, Mounting groove 2 18, Linkage part 19, Linkage groove 20, Anti-detachment part 21, Ejector plate 22, Ejector pin 23, Through groove 24, Limiting inclined surface 1 25, Limiting inclined surface 2 26, Rack 27, Drive cylinder 28, Telescopic groove 29, Injection groove 30, Injection hole 31, Hole 1 32, Hole 2 33, Vent 34, Inlet 35, Hole 36, Hole 4 37, Main air hole 38, Guide rail 39, Sliding part 40. Detailed Implementation

[0042] 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.

[0043] For reference as follows Figures 1-18 The present invention will be described as follows: Example: A rotating core-pulling mold is used for injection molding of bent pipe and elbow-shaped plastic products. Its purpose is to solve the technical pain points of existing bent pipe injection molding core-pulling demolding operations, such as complex operation, low efficiency and poor product molding quality. By combining rotating core-pulling and linear core-pulling, the mold can achieve efficient and high-quality demolding of bent pipe products.

[0044] It includes upper mold 1 and lower mold 2.

[0045] The lower mold 2 serves as the fixed base for the mold. During use, it is fixedly installed on the frame of the injection molding equipment with bolts and other fasteners to ensure the overall position of the mold is stable and without displacement deviation during injection and demolding.

[0046] The upper mold 1 is a movable structure that can move up and down along the equipment guide mechanism to complete the mold closing and opening actions. To ensure the accuracy of the up and down movement of the upper mold 1 and avoid misalignment during mold closing, a guide rod extending vertically downward is provided on the lower surface of the upper mold 1. Correspondingly, a guide hole that perfectly matches the size and position of the guide rod is provided on the upper surface of the lower mold 2. During mold closing, the guide rod is inserted into the guide hole to achieve precise alignment between the upper mold 1 and the lower mold 2, ensuring the sealing of the molding cavity 3 and the molding accuracy.

[0047] After the upper mold 1 and the lower mold 2 are closed, a forming cavity 3 is formed between them for product forming. The structure of the forming cavity 3 is adapted to the shape of the bent pipe or elbow product to be formed. Specifically, it is an arc-shaped structure with a circular cross-section, which is consistent with the cross-sectional dimensions of the bent pipe product.

[0048] The included angle between the central axes of the two ends of the forming cavity 3 is set to 90 degrees, which is suitable for the forming requirements of common right-angle bend products. If it is necessary to adapt to bends of other angles, the curvature of the forming cavity 3 and the included angle of the ends can be adjusted.

[0049] The molding cavity 3 is equipped with a core 4, which is an arc-shaped structure. Its curvature and cross-sectional dimensions correspond to those of the molding cavity 3. The core 4 and the inner wall of the molding cavity 3 are separated by a gap. This gap is the injection molding space for the bent pipe product. After the molten plastic is injected into this space, it cools and solidifies to form the bent pipe product.

[0050] One end of the core 4 is fixedly connected to the rotating block 5. The size of the rotating block 5 is larger than the size of the corresponding port of the molding cavity 3. It can close one end port of the molding cavity 3 to prevent molten plastic from overflowing from the port during injection molding. At the same time, it serves as a support and transmission component for the core 4, driving the core 4 to rotate and pull the core.

[0051] Core 2 9 is located at the other end of core 4. Core 2 9 is a cylindrical structure with a diameter larger than the size of the other end of the molding cavity 3 and the end size of core 4. It can close the other end of the molding cavity 3, forming a closed injection space together with core 4, rotating block 5, and molding cavity 3, ensuring that the molten plastic can be completely formed within the molding cavity 3. Core 2 9 abuts against the end of core 4, and the abutment surfaces fit tightly to prevent material leakage during injection molding.

[0052] The positioning assembly is mainly used to accurately position and fix the rotating block 5, core 1 4, slider 11, and core 2 9 after mold closing, ensuring that there is no displacement of each component during injection molding and guaranteeing the molding accuracy of the product. Specifically, it includes four parts: positioning groove 1 6, rotating groove 7, positioning groove 2 12, and sliding groove 13. The lower surface of the upper mold 1 is provided with a positioning groove 6. The shape and size of the positioning groove 6 are adapted to the upper structure of the rotating block 5. After the mold is closed, the upper side of the rotating block 5 is embedded in the positioning groove 6. The inner wall of the positioning groove 6 limits the rotating block 5 to prevent it from rotating or displacing during the injection molding process, thereby achieving the positioning and fixing of the core 4.

[0053] The upper surface of the lower mold 2 is provided with a rotating groove 7. The rotating groove 7 is an arc-shaped structure, and its central axis is coaxial with the central axis of the core 4. The lower side of the rotating block 5 is slidably connected to the rotating groove 7. This structural design allows the rotating block 5 to rotate smoothly along the arc direction of the rotating groove 7, thereby driving the core 4 to rotate synchronously, providing motion trajectory guidance for the rotation and core pulling of the core 4.

[0054] After the upper mold 1 and the lower mold 2 are closed, a receiving cavity 10 is formed between them. The receiving cavity 10 is connected to the molding cavity 3 and is used to receive the core 2 9 and the slider 11.

[0055] The end of the second core 9 away from the first core 4 is fixedly connected to the slider 11, and the two adopt an integral molding structure. This design can enhance the connection strength between the second core 9 and the slider 11, avoid loosening during transmission, reduce assembly errors, and ensure the movement accuracy of the second core 9.

[0056] The lower surface of the upper mold 1 is provided with a positioning groove 2 12, the shape and size of which are adapted to the upper structure of the slider 11. After the mold is closed, the upper side of the slider 11 is embedded in the positioning groove 2 12, thereby fixing the slider 11 and the core 2 9 and preventing the slider 11 from sliding and the core 2 9 from shifting during the injection molding process.

[0057] The upper surface of the lower mold 2 is provided with a slide groove 13. The extension direction of the slide groove 13 is completely consistent with the axial direction of the second core 9. The lower side of the slider 11 is slidably connected to the slide groove 13. The slide groove 13 provides guidance for the movement of the slider 11, ensuring that the slider 11 drives the second core 9 to make a smooth linear movement, thereby realizing the linear core pulling and demolding of the second core 9.

[0058] The core-pulling drive assembly consists of two parts, which drive core 4 to achieve rotational core pulling and core 9 to achieve linear core pulling. The two drive assemblies work together to complete the core-pulling action in a preset sequence, ensuring a smooth and efficient demolding process. The specific structure and working principle are as follows: The lower mold 2 is equipped with a rotatable gear 8. The central axis of the gear 8 is coaxial with the central axis of the rotating groove 7 and the central axis of the core 4, ensuring that the gear 8 can drive the rotating block 5 and the core 4 to rotate smoothly along the preset trajectory when it rotates.

[0059] The rotating block 5 is fixedly connected to the gear 8. Specifically, the lower side of the rotating block 5 extends downward to form a linkage part 19. The upper surface of the gear 8 is provided with a linkage groove 20 that matches the size and shape of the linkage part 19. The linkage part 19 is embedded in the linkage groove 20 to realize the synchronous transmission between the rotating block 5 and the gear 8.

[0060] Meanwhile, the lower end face of the linkage part 19 abuts against the bottom surface of the mounting groove 18. This abutting structure can support the rotating block 5, preventing the rotating block 5 from shifting up and down during rotation and ensuring rotational stability.

[0061] The lower mold 2 is equipped with a drive device for rotating the drive gear 8. The drive device consists of a rack 27 and a drive cylinder 28. The specific structure is as follows: the lower mold 2 is provided with a telescopic groove 29 that runs through both sides of it. The telescopic groove 29 is connected to the mounting groove 18. The rack 27 is slidably connected in the telescopic groove 29 and meshes with the gear 8. The drive cylinder 28 is fixed to the outer wall of the lower mold 2 by bolts or other fasteners. The output end of the drive cylinder 28 is connected to the rack 27 and is used to drive the rack 27 to perform reciprocating linear motion along the telescopic groove 29.

[0062] The drive cylinder 28 can be either a pneumatic cylinder or a hydraulic cylinder, which can be selected according to actual production needs and equipment configuration. Its working principle is as follows: When the drive cylinder 28 extends or retracts, it drives the rack 27 to move along the extension groove 29. The rack 27 meshes with the gear 8, driving the gear 8 to rotate forward or backward. The gear 8, through the cooperation of the linkage part 19 and the linkage groove 20, drives the rotating block 5 and the core 4 to rotate along the rotating groove 7, thereby realizing the rotation, core pulling, and reset of the core 4. The linear core-pulling action of core 2 9 is achieved through the up-and-down movement of the upper mold 1 and the cooperation of the inclined ejector pin 14 and the insertion slot 15. The specific structure is as follows: An inclined ejector rod 14 is fixedly provided on the lower surface of the upper mold 1, and an insertion groove 15 is provided on the upper surface of the slider 11 that is perfectly matched with the size and tilt angle of the inclined ejector rod 14. The inclined ejector rod 14 and the insertion groove 15 can be inserted and matched accordingly.

[0063] Its working principle is as follows: During the mold closing process, as the upper mold 1 moves downward, the inclined ejector rod 14 gradually inserts into the insertion slot 15. Since the inclined ejector rod 14 is inclined, it will generate a horizontal thrust on the slider 11 during the insertion process, driving the slider 11 to move along the slide groove 13 towards the molding cavity 3, thereby driving the second core 9 to move synchronously until the end of the second core 9 abuts against the end of the first core 4, completing the closure of the other end of the molding cavity 3.

[0064] During the mold opening process, as the upper mold 1 moves upward, the inclined ejector rod 14 gradually disengages from the insertion groove 15. During the disengagement process, it generates a reverse horizontal pulling force on the slider 11, driving the slider 11 to move along the slide groove 13 in a direction away from the molding cavity 3, thereby driving the core 2 9 to move synchronously, realizing the linear core pulling demolding of the core 2 9.

[0065] To ensure a smooth core-pulling process and avoid interference between the core and the product or mold, the core-pulling action is performed in a preset sequence, specifically divided into the reset sequence during mold closing and the core-pulling sequence during mold opening: (1) Mold closing and reset sequence: Before mold closing, core 1 4 and core 2 9 are both in a position far away from the molding cavity 3. When the mold is closed, the drive device first drives the gear 8 to rotate. The gear 8 drives the rotating block 5 and core 1 4 to rotate towards the molding cavity 3 until core 1 4 is completely inside the molding cavity 3 and the rotating block 5 is tightly attached to the port of the molding cavity 3, thus completing the closure of one end of the molding cavity 3. Then, the upper mold 1 moves downward, the guide rod is inserted into the guide hole to achieve precise alignment, and at the same time, the inclined ejector rod 14 is inserted into the insertion slot 15, gradually driving the slider 11 and core 2 9 to move towards the molding cavity 3 until the end of core 2 9 and core 1 4 abuts together, thus completing the closure of the other end of the molding cavity 3. At this time, the positioning slot 1 6 and the rotating block 5, and the positioning slot 2 12 and the slider 11 are all adapted and positioned. The molding cavity 3, core 1 4, rotating block 5, and core 2 9 together form a closed injection space, and the injection molding operation can be carried out.

[0066] (2) Mold opening and core pulling sequence: After injection molding is completed and the product cools and solidifies, mold opening and core pulling begin; First, the upper mold 1 moves upward, the guide rod comes out from the guide hole, and at the same time the inclined ejector rod 14 comes out from the insertion groove 15, driving the slider 11 and the second core 9 to move away from the molding cavity 3 along the slide groove 13 until the front end of the second core 9 is completely pulled out from the inner cavity of the injection molded product, completing the linear core pulling demolding of the second core 9; Subsequently, the drive device drives the gear 8 to rotate in the opposite direction, and the gear 8 drives the rotating block 5 and the first core 4 to rotate away from the molding cavity 3 along the rotating groove 7 until the first core 4 is completely pulled out from the inner cavity of the injection molded product, completing the rotational core pulling demolding of the first core 4; Finally, the ejector pin 23 pushes the molded product out from the molding cavity 3, completing the entire demolding process.

[0067] To facilitate the processing, assembly and maintenance of the mold, the mold adopts a modular design. Specifically, the upper side of the lower mold 2 is provided with an installation groove 16, and the lower module 17 is adapted and connected in the installation groove 16. The lower module 17 is fixedly connected to the lower mold 2 by bolts and other fasteners.

[0068] The lower surface of the upper mold 1 is provided with a corresponding mounting groove, and the upper module is adapted and connected in the mounting groove. The upper module is also fixedly connected to the upper mold 1 by fasteners.

[0069] The forming cavity 3 is composed of a lower module 17 and an upper module. The upper surface of the lower module 17 and the lower surface of the upper module each have an arc-shaped groove. After mold closing, the two arc-shaped grooves join together to form a complete arc-shaped forming cavity 3. The advantage of this design is that when the size of the forming cavity 3 needs to be changed to accommodate different specifications of bent pipe products, it is not necessary to replace the entire upper or lower mold; only the corresponding upper and lower modules need to be replaced, reducing mold maintenance costs and improving mold versatility. At the same time, the modular design facilitates the processing and cleaning of the forming cavity 3, reducing the difficulty of mold processing.

[0070] The bottom of mounting slot 16 is provided with mounting slot 2 18. The size of mounting slot 2 18 is adapted to gear 8. Gear 8 is rotatably connected in mounting slot 2 18. The specific connection method is as follows: a shaft hole is provided in the center of gear 8, and a shaft adapted to the size of the shaft hole is fixedly provided at the bottom of mounting slot 2 18. Gear 8 is sleeved on the shaft through the shaft hole and can rotate freely around the shaft, ensuring that the rotation of gear 8 is smooth and without deviation.

[0071] The rotating groove 7 is located on the upper surface of the lower module 17 and communicates with the mounting groove 18, ensuring that the linkage part 19 of the rotating block 5 can pass smoothly through the rotating groove 7 and connect with the linkage groove 20 of the gear 8.

[0072] Since the slide groove 13 is provided through one side of the lower mold 2, in order to prevent the slider 11 from being dislodged from the lower mold 2 along the slide groove 13 during the sliding process, which would lead to the core 2 9 falling off and the mold being damaged, an anti-dislodging component 21 is provided on this side of the lower mold 2. The anti-dislodging component 21 is detachably connected to the lower mold 2.

[0073] The specific structural optimization design is as follows: two guide rails 39 are spaced apart on the upper surface of the lower mold 2, and grooves 13 are respectively provided on the facing surfaces of the two guide rails 39. Sliding parts 40 that are slidably connected to the grooves 13 are respectively provided on both sides of the slider 11. This structure can enhance the stability of the slider 11 sliding and prevent the slider 11 from tilting during the sliding process. The anti-detachment part 21 is a long strip structure, and its two ends are fixedly connected to the two guide rails 39 by bolts, covering the through port of the groove 13. Structurally, it prevents the slider 11 and the core 2 9 from moving out of the lower mold 2 along the groove 13. The detachable design facilitates the installation, disassembly and maintenance of the slider 11.

[0074] The ejector assembly is used to eject the molded product from the molding cavity 3 after the core 1 4 and core 2 9 have completed the core pulling process, making it easy to remove the product. Its structure includes an ejector plate 22 and multiple ejector pins 23.

[0075] The lower mold 2 is provided with an ejector plate 22 that can move up and down. The ejector plate 22 is connected to the ejection mechanism of the injection molding equipment and is driven by the equipment to move up and down. Multiple ejector pins 23 are fixedly connected to the upper surface of the ejector plate 22. The upper end of the ejector pin 23 passes through the lower mold 2 and the lower mold module 17 and extends into the molding cavity 3. Their position and number are based on the structural design of the bent tube product to ensure that the force can be evenly distributed during ejection and to avoid product deformation.

[0076] Since some of the ejector pins 23 need to pass through the gear 8, to prevent interference between the gear 8 and the ejector pins 23 during rotation, which could lead to the gear 8 jamming or damage to the ejector pins 23, a through groove 24 corresponding to the ejector pins 23 is provided on the gear 8. The through groove 24 is arranged circumferentially along the gear 8, and its width is adapted to the ejector pins 23. When the gear 8 rotates, the ejector pins 23 remain stationary, while the through groove 24 rotates with the gear 8, allowing relative movement between the ejector pins 23 and the gear 8. This effectively avoids interference between the two and ensures the normal operation of the ejection assembly and the core-pulling drive assembly.

[0077] To further improve the positioning stability of the rotating block 5 and the slider 11 after mold closing, and to prevent the rotating block 5 from rotating and the slider 11 from sliding due to injection pressure during the injection process, limit slope structures are respectively provided on the rotating block 5 and the slider 11: (1) Limiting slope of rotating block: A limiting slope 25 is formed on the upper side of rotating block 5. A corresponding slope that is completely in contact with the limiting slope 25 is formed on the inner wall of positioning groove 6. After the mold is closed, the limiting slope 25 is tightly in contact with the inner wall of positioning groove 6. By using the limiting effect of the slope, the rotating block 5 is prevented from rotating away from the core 9, which further strengthens the positioning and fixing effect of rotating block 5 and core 4.

[0078] (2) Limiting slope of slider: Limiting slope 26 is formed on the upper side of slider 11. A corresponding slope that is completely in contact with limiting slope 26 is formed on the inner wall of positioning groove 2 12. After mold closing, limiting slope 26 is tightly in contact with the inner wall of positioning groove 2 12. By limiting the slope, slider 11 is prevented from sliding away from core 1 4, which strengthens the positioning and fixing effect of slider 11 and core 2 9 and ensures the stability of the position of each component during injection molding.

[0079] The injection molding structure is used to inject molten plastic into the molding cavity 3. Its structure includes an injection groove 30 and an injection hole 31: the upper side of the lower module 17 is provided with an injection groove 30, which communicates with the molding cavity 3; the upper mold 1 is provided with an injection hole 31, which penetrates the upper and lower sides of the upper mold 1, with its lower end communicating with the injection groove 30 and its upper end connected to the injection port of the injection molding equipment. During injection molding, molten plastic enters the injection hole 31 through the injection port of the injection molding equipment, flows into the injection groove 30 through the injection hole 31, and is then evenly distributed to various parts of the molding cavity 3 by the injection groove 30, ensuring that the product is fully molded without any missing material.

[0080] The mating surfaces of core 2 9 and core 1 4 are respectively provided with corresponding connecting holes 1 32 and 2 33. The sizes of hole 1 32 and hole 2 33 are matched. After the mold is closed, the two are connected to form a channel that runs through core 1 4 and core 2 9.

[0081] A sealing ring is installed on the mating surfaces of core 2 9 and core 1 4 to prevent leakage at the connection between hole 1 32 and hole 2 33.

[0082] The slider 11 and the core 2 9 are an integral structure, and a cooling channel is provided inside. One end of the cooling channel is connected to the hole 32, and the other end is connected to the air outlet 34 provided on the outer wall of the slider 11.

[0083] The rotating block 5, the core 4, and the linkage part 19 are integrated into one structure. A cooling channel is also provided inside the channel. One end of the cooling channel is connected to the hole 33, and the other end is connected to the air inlet 35 provided on the lower end face of the linkage part 19.

[0084] The above structure forms a complete cooling air passage, providing a path for gas flow.

[0085] The bottom surface of the mounting slot 2 18 is provided with holes 36 and 4. Holes 36 and 4 are both located on the rotation trajectory of the linkage part 19 and are adapted to the size of the air inlet 35.

[0086] The outer side wall of the lower mold 2 is provided with a main air hole 38, which is connected to an external air source device. The interior of the lower mold 2 is provided with a connecting channel, which connects the main air hole 38 to hole three 36 and the main air hole 38 to hole four 37, respectively, so as to realize the connection between the external air source and the cooling channel.

[0087] There are two main air holes 38, which are respectively set to correspond to holes 36 and 4 37. The two main air holes 38 are respectively connected to holes 36 and 4 37 through channels.

[0088] When the mold is closed, the air inlet 35 of the linkage part 19 is connected to the third hole 36; after the mold is opened, the linkage part 19 rotates with the rotating block 5, and the air inlet 35 is connected to the fourth hole 37, realizing the switching of the air path.

[0089] A sealing ring is provided on the lower side of the linkage part 19, and the air inlet 35 is located inside the sealing ring to prevent leakage from the connection between the air inlet 35 and the third hole 36 and the fourth hole 37.

[0090] After the product injection molding is completed, the product enters the cooling and curing stage. At this time, the external air source device is activated and sends gas for auxiliary cooling (compressed air or inert gas can be selected) into the main air hole 38. The gas enters the third hole 36 through the connecting channel inside the lower mold 2, and then enters the air inlet 35 of the linkage part 19 through the third hole 36. It flows through the cooling channel inside the rotating block 5 and the first core 4, and enters the cooling channel inside the second core 9 and the slider 11 through the docking of the second hole 33 and the first hole 32. Finally, it is discharged from the air outlet 34 of the slider 11.

[0091] As the gas flows through the cooling channel, it exchanges heat with core 4 and core 9, carrying away the injection heat absorbed by the cores. This accelerates the cooling and solidification of the molten plastic in the molding cavity 3, shortens the production cycle, improves the uniformity of product cooling, reduces product shrinkage and deformation, and ensures product molding quality.

[0092] After the mold is opened, the molded product is ejected. At this time, a small amount of molten plastic debris or impurities may remain on the inner wall of the molding cavity 3, affecting the molding of subsequent products. At this time, the external air source device continues to send gas into the main air hole 38. The gas enters the fourth hole 37 through the connecting channel inside the lower mold 2, and then enters the air inlet 35 of the linkage part 19 through the fourth hole 37. It flows through the cooling channel inside the rotating block 5 and the core 4, and finally sprays out from the second hole 33 (at this time, the second hole 33 is separated from the first hole 32). The sprayed gas directly acts on the inner wall of the molding cavity 3, blowing away the residual plastic debris or impurities, realizing automatic cleaning of the molding cavity 3 without manual cleaning, improving production efficiency, and avoiding the impact of residual impurities on the molding accuracy and surface quality of subsequent products.

[0093] The advantages of this invention, which employs the above technical solution, are as follows: Simple core-pulling operation and high demolding efficiency: This mold is designed for the structural characteristics of bent tube products. It adopts a combination of rotating core 1 (4) and linear core 2 (9) for core-pulling. The arc-shaped core 1 (4) is adapted to the inner cavity of the bent tube. After injection molding, core 1 (4) can be driven by gear 8 to rotate and pull out the core in one go. There is no need to use a split core for step-by-step core pulling, which simplifies the core-pulling steps, reduces the difficulty of operation, shortens the core-pulling cycle, and improves the overall production efficiency.

[0094] Core 14 adopts an integral arc-shaped structure with no splicing gaps, avoiding the splicing marks on the inner wall of the product caused by the splicing gaps of the existing split cores, improving the smoothness of the inner wall and the molding accuracy of the bent tube products; at the same time, the positioning of each component is accurate after the mold is closed, there is no displacement during the injection molding process, and the cooling is uniform, effectively reducing defects such as product shrinkage deformation and scratches, and improving the product qualification rate.

[0095] The mold core 4 and the mold core 9 are equipped with interconnected cooling channels. Cooling gas is introduced through an external air source to quickly cool and solidify the product, shortening the production cycle. After the mold is opened, the same air source can be used to automatically clean the molding cavity 3 by switching the air path, reducing manual operation, improving production efficiency, and ensuring the molding quality of subsequent products.

[0096] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. 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 rotating core-pulling mold, comprising an upper mold and a lower mold, wherein a forming cavity is provided between the upper mold and the lower mold, characterized in that: The molding cavity is provided with an arc-shaped core. One end of the core is fixedly connected to a rotating block. The upper mold is provided with a positioning groove that is connected to the upper side of the rotating block. The lower mold is provided with a rotating groove that is slidably connected to the lower side of the rotating block. The rotating groove is arc-shaped, and the central axis of the rotating groove is coaxial with the central axis of the core. The lower mold is equipped with a rotatable gear, the central axis of which is coaxial with the central axis of the rotating groove. The rotating block is fixedly connected to the gear, and the lower mold is equipped with a drive device to drive the gear to rotate. The other end of the core one is provided with a core two that abuts against it. The core two is cylindrical, and a receiving cavity connected to the core two is formed between the upper mold and the lower mold. The end of the second core away from the first core is fixedly connected to a slider. The upper mold is provided with a positioning groove 2 that is adapted to and connected to the upper side of the slider. The lower mold is provided with a sliding groove that is slidably connected to the lower side of the slider. The upper mold is equipped with an inclined ejector rod, and the slider is equipped with an insertion slot corresponding to the inclined ejector rod. The upper side of the lower mold is equipped with a mounting groove 1, within which a lower module is fitted and connected. The bottom of mounting groove 1 is equipped with a mounting groove 2 that is fitted and connected to a gear. A rotating groove is provided on the lower module, and the lower side of the rotating block extends downwards to form a linkage part. The gear is equipped with a linkage groove that connects to the linkage part, and the lower end face of the linkage part abuts against the bottom surface of mounting groove 2. The slider and core 2 are integrally formed, as are the rotating block, core 1, and linkage part. Core 2 and core 1 are integrally formed. The mating surfaces are respectively provided with corresponding connecting holes one and two; the outer wall of the slider is provided with an air outlet, and the interior of the slider and the core two is provided with a cooling channel connecting hole one and the air outlet; the lower end face of the linkage is provided with an air inlet, and the interior of the rotating block, the core one, and the linkage part is provided with a cooling channel connecting hole two and the air inlet; the bottom surface of the mounting groove two is provided with holes three and four corresponding to the air inlet, and holes three and four are located in the rotation direction of the linkage part; the outer wall of the lower mold is provided with a main air hole, and the interior of the lower mold is provided with a channel connecting the main air hole and hole three and hole four.

2. The rotating core-pulling mold according to claim 1, characterized in that: The groove is provided through one side of the lower mold, and an anti-detachment component is detachably connected to one side of the lower mold to prevent the slider from detaching from the groove.

3. A rotating core-pulling mold according to claim 1, characterized in that: The lower mold is connected to a movable ejector plate, which has multiple ejector pins connected to it. Some of the ejector pins pass through the gears. The gears are provided with through slots corresponding to the ejector pins, and the through slots are arranged along the circumference of the gears.

4. A rotating core-pulling mold according to claim 1, characterized in that: The upper side of the rotating block forms a limiting inclined surface one, which cooperates with the upper mold to prevent the rotating block from rotating away from the core two.

5. A rotating core-pulling mold according to claim 1, characterized in that: The upper side of the slider forms a limiting inclined surface two, which cooperates with the upper mold to prevent the slider from sliding away from the core one.

6. A rotating core-pulling mold according to claim 1, characterized in that: The driving device includes a rack and a driving cylinder. The lower mold is provided with a telescopic groove that runs through both sides of it. The telescopic groove is connected to the mounting groove. The rack is slidably connected in the telescopic groove and meshes with the gear. The driving cylinder is fixed on the outer side wall of the lower mold and is used to drive the rack to move back and forth.

7. A rotating core-pulling mold according to claim 1, characterized in that: The lower module is provided with an injection groove that communicates with the molding cavity, and the upper mold is provided with an injection hole that communicates with the injection groove, the injection hole penetrating the upper side of the upper mold.

8. A rotating core-pulling mold according to claim 2, characterized in that: The lower mold is provided with two guide rails spaced apart, and the opposing surfaces of the guide rails are respectively provided with sliding grooves. The two sides of the slider are respectively provided with sliding parts that are slidably connected to the sliding grooves. The anti-detachment component is long and strip-shaped, and the two ends of the anti-detachment component are fixedly connected to the two guide rails by bolts.

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