Efficient exhaust centrifugal mold for PU tire production and use method

Abstract

The invention relates to the technical field of PU tire molds, in particular to an efficient exhaust centrifugal mold for PU tire production and a using method. According to the technical scheme, the mold comprises a base, a mounting frame, an upper mold, a lower mold, a hollowed-out frame, an assembly valve, a valve rod and an adjusting rod, a mounting plate is arranged in the mounting frame, an assembly groove is formed in the inner wall of the upper mold, a snakelike exhaust groove hole is formed in the assembly valve, and the exhaust groove hole comprises a snakelike groove section, a tail end groove and a starting groove; an adjusting groove is formed in the exhaust groove hole, a valve ring and a first supporting ring are arranged on the inner wall of the starting groove, and a first extrusion block and a second extrusion block are arranged on the outer wall of the hollowed-out frame. By arranging the annular array snakelike exhaust groove holes, the extrusion linkage type valve element, the scraping ring, the ball transmission structure and the inclination angle adjusting mechanism, efficient staged exhaust, liquid material leakage-proof recovery and exhaust channel self-cleaning during PU tire forming are achieved, and meanwhile the mold operation convenience and running stability are improved.

Description

Technical Field

[0001] This invention relates to the field of PU tire mold technology, and in particular to a high-efficiency venting centrifugal mold for PU tire production and its usage method. Background Technology

[0002] PU tires, or polyurethane tires, are widely used in industrial casters, small vehicles, and medical devices due to their advantages of wear resistance, good elasticity, high load-bearing capacity, and low noise. Their core manufacturing process primarily utilizes centrifugal casting molding, with the complete process using a high-efficiency degassing centrifugal mold as follows:

[0003] Raw material preparation: Mix polyurethane prepolymer, curing agent, catalyst, filler (such as carbon black, calcium carbonate) and other raw materials according to the formula, and stir evenly to form PU casting material. During the stirring process, the speed and time need to be controlled to avoid introducing too much air.

[0004] Mold pretreatment: Clean the cavity of the high-efficiency venting centrifugal mold, apply release agent, and then preheat to the required process temperature. Preheating can improve the fluidity of PU material and ensure the quality of tire molding.

[0005] Casting and centrifugation: The mixed PU casting material is injected into the mold cavity, and then the mold is fixed on the centrifugal molding machine. The centrifuge is started, and the mold rotates at high speed at the set speed. Centrifugal force is used to make the PU material evenly adhere to the inner wall of the mold cavity to form the tread and carcass structure of the tire.

[0006] Degassing and curing: During centrifugation, the venting structure of the mold is opened to expel the gas inside the mold cavity; at the same time, the PU material undergoes a cross-linking and curing reaction inside the mold cavity, and the curing time is adjusted according to the formula and temperature;

[0007] In the centrifugal molding production of PU tires, the venting effect directly determines the product quality and production efficiency. Traditional PU tire centrifugal molds generally have unreasonable venting design. Most of them use continuous open venting holes, which can easily lead to PU liquid splashing and leakage, resulting in material waste and equipment contamination. Some molds have unevenly distributed venting holes, and gas in some areas of the mold cavity cannot be effectively discharged. Residual air bubbles can cause defects such as pitting and voids in the tire, significantly reducing the tire's mechanical properties and service life.

[0008] Meanwhile, traditional molds lack effective venting and cleaning structures. Small amounts of PU liquid seeping into the venting holes can solidify and cause blockages, requiring frequent shutdowns for cleaning and severely impacting production continuity. Furthermore, the cumbersome opening and closing operations, insufficient rotational stability, and poor tilt angle adaptability of the molds further restrict production efficiency and product consistency, making it difficult to meet the demands of large-scale, high-precision PU tire production. Therefore, those skilled in the art have provided a high-efficiency venting centrifugal mold for PU tire production to address the problems mentioned in the background section. Summary of the Invention

[0009] The purpose of this invention is to address the problems existing in the background art by proposing a high-efficiency exhaust centrifugal mold for PU tire production and its usage method.

[0010] To achieve the above objectives, the present invention provides the following technical solution: a high-efficiency venting centrifugal mold for PU tire production, comprising a base, a mounting frame, an upper mold, a lower mold, a hollow frame, an assembly valve, a valve stem, and an adjusting rod. The mounting frame is positioned above the base, and an mounting plate is positioned inside the mounting frame. A closed lower mold and an upper mold are positioned above the mounting plate. The inner wall of the upper mold has assembly grooves arranged in a circular array and penetrating the internal mold cavity. A columnar assembly valve is positioned inside the assembly grooves. The assembly valve has a serpentine venting groove, which includes a serpentine groove section in the middle, an end groove penetrating the upper mold cavity, and a starting groove communicating with the outside. The venting slot has an adjustment slot inside that communicates with the end slot and has one end connected to the outside. The inner wall of the starting slot is provided with a valve ring and a support ring one. The valve ring has a conical valve core inside. A valve spring is provided between the valve core and the support ring one. The inner wall of the adjustment slot is provided with a support ring two. The adjustment slot has a scraper ring whose sliding path is located inside the end slot. A spring is provided between the scraper ring and the support ring two. One end of the scraper ring is provided with an adjustment rod located inside the support ring two. The center of the mounting plate is provided with a hydraulic rod three. The telescopic end of the hydraulic rod three is provided with a hollow frame. The outer wall of the hollow frame is provided with extrusion blocks one and two arranged in a ring array.

[0011] Preferably, the upper end of the base is provided with a hydraulic rod connected to the lower end of the mounting frame, and symmetrically distributed guide posts are provided on both sides of the upper end of the base. Both ends of the mounting frame are provided with guide plates that slide against the outer walls of the guide posts. The hydraulic rod drives the mounting frame to move longitudinally, thereby causing the tire molds (upper mold and lower mold) to move longitudinally. The longitudinal movement of the mounting frame is guided by the guide plates sliding against the outer walls of the guide posts.

[0012] Preferably, a support plate is provided below the mounting plate, and a second hydraulic rod with its telescopic end connected to the lower end of the support plate is provided inside the mounting frame. When the second hydraulic rod drives the support plate to move longitudinally, it fits against the lower end of the mounting plate and supports the bottom of the mounting plate, thereby improving the stability of the tire mold, which is rotated and supported by the adjusting shaft, during centrifugal use.

[0013] Preferably, the upper mold has a first ring inside, and the lower mold has a second ring inside. The hollow frame is suspended inside the first ring and stored inside the second ring after use. One end of the adjusting rod and the valve rod are located inside one side of the ring. The first and second rings facilitate the longitudinal sliding of the hollow frame, and the tire mold does not interfere with the hollow frame when rotating.

[0014] Preferably, a ball bearing 1 is rotatably mounted at one end of the valve stem inside the first ring, and a ball bearing 2 is rotatably mounted at one end of the adjusting rod inside the first ring. The first extrusion block compresses the rotating ball bearing 1, and the second extrusion block compresses the rotating ball bearing 2. The first extrusion block and the ball bearing 1 are on the same horizontal plane, and the second extrusion block and the ball bearing 2 are on the same horizontal plane. The first extrusion block is located above the second extrusion block. When the tire mold rotates, it drives the adjusting rod and the valve stem to rotate. The ball bearing 1 reduces the friction and resistance of the valve stem when passing through the first extrusion block, and the ball bearing 2 reduces the friction and resistance of the adjusting rod when passing through the second extrusion block. The adjusting rod and the second extrusion block, as well as the valve stem and the first extrusion block, do not interfere with each other.

[0015] Preferably, a sealing seat is provided on the inner wall of the assembly groove, and the assembly valve is slidably installed inside the sealing seat. After the assembly valve is assembled inside the sealing seat, one end of the assembly valve is provided with a mating surface that adapts to the arc surface of the inner wall of the upper mold cavity. The assembly valve is sealed and assembled inside the assembly groove through the sealing seat, and the mating surface adapts to the mold cavity after the assembly valve is assembled inside the sealing seat, without interfering with the forming of the tire.

[0016] Preferably, the inner wall of the ring core is provided with a mating ring located at the opening of the assembly groove, and the outer wall of the assembly valve is provided with a mating ring. The mating ring has mounting holes arranged in a ring array on its inner side. After the assembly valve is assembled into the assembly groove, it is fixed together by the mating ring and then secured by parts installed in the mounting holes.

[0017] Preferably, the upper mold has a male buckle at one end, and the lower mold has a female buckle at one end that engages and locks with the male buckle. The lower mold also has a mounting frame at one end, and a second motor and a battery are mounted on one end of the mounting frame. The output end of the second motor has a rotating shaft rotatably mounted inside the mounting frame, and a side block connected to the upper mold is sleeved on the outer wall of the rotating shaft. The upper and lower molds are fixed together by the male and female buckles. When the second motor drives the rotating shaft to rotate, it causes the side block to rotate, thus controlling the opening and closing of the upper mold. The second motor itself is powered by a battery.

[0018] Preferably, a motor is mounted on one side of the upper end of the mounting plate, a gear is mounted on the output end of the motor, a gear ring meshing with the gear is mounted on the lower end of the lower mold, an annular raceway is mounted on the upper side of the mounting plate, and an annular pulley is mounted on the lower side of the upper mold and rolled inside the raceway. When the motor drives the gear to rotate, it pushes the gear ring to rotate, thereby driving the lower mold to rotate. The lower mold rolls inside the raceway via the pulley, improving the stability of the tire mold rotation.

[0019] Preferably, both ends of the mounting plate are provided with adjusting shafts that rotate inside the mounting side frame. A gear two is sleeved on the outer wall of the adjusting shaft. A hydraulic rod four is provided on the inner wall of one side of the side frame. A connecting block is provided at the telescopic end of the hydraulic rod four. A toothed plate that meshes with the gear two is provided at the upper end of the connecting block. A groove is formed at one end of the toothed plate. A guide rail that slides inside the groove is provided on the inner wall of the side frame. The hydraulic rod four drives the toothed plate to push the gear two, causing the adjusting shaft to rotate, which in turn causes the mounting plate to rotate, adjusting the tilt angle of the tire mold. This is suitable for use with automated cleaning equipment and for spraying mold release agent into the mold cavity before production.

[0020] A method for using a high-efficiency venting centrifugal mold for PU tire production includes the following steps:

[0021] S1. Mold Pretreatment

[0022] Mold cleaning and tilt adjustment: Start hydraulic rod four, which drives the adjustment shaft to rotate through the meshing of the toothed plate and gear two, adjusting the tilt angle of the mounting plate and the mold to adapt to automated cleaning equipment; open the upper mold and thoroughly clean the mold cavities of the upper and lower molds to remove residual material, solidified liquid and impurities, ensuring that the inner wall of the mold cavity is smooth.

[0023] Applying release agent and preheating: After cleaning, reverse the hydraulic rod to reset the mold tilt angle; apply release agent evenly to the inner wall of the mold cavity to prevent the PU material from sticking after curing; start the mold preheating system to raise the mold cavity temperature to 45-55℃ and keep it at that temperature for 10-15 minutes to improve the fluidity of the PU material and ensure molding quality.

[0024] Valve inspection and fixing: Confirm that the serpentine vent hole in the assembly valve is unobstructed and that the valve core and scraper ring slide flexibly; slide the assembly valve into the assembly groove of the upper mold, and lock it with fasteners through the mounting holes of the mating ring to ensure that the mating surface is completely in contact with the arc surface of the inner wall of the mold cavity, and the sealing seat achieves sealing at the assembly point.

[0025] S2, Mold Closure and Casting

[0026] Mold closing and locking: Start motor two, powered by battery, drives the rotating shaft to rotate the side block, and the upper mold closes with the side block to the lower mold; the male and female buckles are locked together to ensure a tight seal on the parting surface and prevent liquid leakage during centrifugation.

[0027] Mold support reinforcement: Activate hydraulic rod two to drive the support plate to move upward until it is tightly fitted with the lower end of the mounting plate, forming a rigid bottom support to prevent the mold from eccentrically shaking or deforming during high-speed rotation.

[0028] PU casting material injection: Mix polyurethane prepolymer, curing agent, catalyst and filler according to the formula, and stir evenly to form PU casting material (control the speed and time during stirring to reduce air mixing); slowly inject the mixed PU casting material along the edge of the lower mold cavity, the pouring volume is 92%-95% of the cavity volume, and leave space for centrifugal molding and curing shrinkage.

[0029] S3, Centrifugal molding and core function operation (exhaust, channel self-cleaning)

[0030] Positioning the cutout frame: Activate the hydraulic rod three in the center of the mounting plate to drive the cutout frame to move upward and suspend it inside the annulus one of the upper mold, ensuring that the extrusion blocks one and two on the outer wall of the cutout frame are at the same level as the ball ends of the valve rod and adjusting rod.

[0031] Start centrifugal rotation: Start motor one, whose output shaft drives gear one to rotate, which in turn drives the lower mold to rotate through meshing with the gear ring. The upper mold rotates synchronously with the lower mold. The pulley at the lower end of the upper mold rolls along the raceway of the mounting plate to reduce rotational friction. Adjust the speed according to the process of "low speed start (300-500r / min), uniform speed acceleration, and stable high speed (1200-1800r / min)". Under the action of centrifugal force, the PU material is evenly attached to the inner wall of the mold cavity to form the tire tread and tire body structure.

[0032] Staged venting (automatic linkage): When the mold rotates, the valve stem and adjusting rod rotate synchronously with the mold. The first and second balls at their ends periodically contact the first and second extrusion blocks of the hollow frame. When the first ball is squeezed by the first extrusion block, the valve stem pushes the conical valve core to compress the valve spring. The valve core disengages from the valve ring, and the venting slot opens. Air and gases generated by chemical reactions in the mold cavity are discharged through the end slot, the serpentine slot section, and the starting slot. After the first extrusion block disengages, the valve spring drives the valve core to reset, and the venting slot closes, achieving staged venting that opens 8 times per revolution, each time for 0.2-0.5 seconds, thus preventing liquid splashing.

[0033] Self-cleaning of the exhaust channel and recovery of liquid material: When the second ball is squeezed by the second extrusion block, the adjusting rod compresses the spring, which drives the scraper ring to slide in the end groove, scraping off the small amount of PU liquid material that has seeped in and pushing it back into the mold cavity, thus realizing the recovery of raw materials; after the second extrusion block is disengaged, the spring drives the scraper ring and the adjusting rod to reset, thus avoiding blockage of the exhaust channel.

[0034] Centrifugation process fine-tuning: The height of the mounting frame is finely adjusted by hydraulic rod one to ensure the coaxiality of the mold rotation; the gas discharge status of the exhaust port is monitored in real time, and the position of the hollow frame is finely adjusted by hydraulic rod three to optimize the contact force between the extrusion block and the valve rod and adjusting rod, ensuring the exhaust and cleaning effect.

[0035] Curing wait: Keep rotating at high speed until the PU material is completely cured. The curing time is adjusted according to the formula and temperature, and is usually controlled within 18-25 minutes.

[0036] S4. Mold opening, part removal, and finished product processing

[0037] Stop rotation and reset support: Turn off motor one, and after the mold has completely stopped rotating, start hydraulic rod two to drive the support plate downwards to reset and release the bottom support.

[0038] Mold opening: Start motor 2 rotates in the opposite direction, driving the upper mold to flip upward and open; hydraulic rod 1 drives the mounting frame to move downward along the guide post, lowering the mold height and facilitating part removal.

[0039] Remove the blank and process the finished product: Remove the tire blank, trim and grind it to remove residual material and burrs from the parting surface; inspect the tire appearance (no pits or bubbles), dimensional accuracy and hardness, and it is a finished product after passing the inspection.

[0040] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0041] This invention injects the mixed PU casting material into the lower mold cavity, then fixes the upper mold onto the lower mold and locks it. The motor is started to drive the gear to rotate, pushing the gear ring to rotate the lower mold, which in turn drives the upper mold to rotate. The tire mold rotates at a set speed, using centrifugal force to make the PU material evenly adhere to the inner wall of the mold cavity, forming the tire tread and carcass structure. During this process, the valve rod and adjusting rod continuously pass through the extrusion block one and extrusion block two. When the valve rod is extruded, the internal channel of the venting slot opens, allowing the gas inside the mold cavity to be discharged. The venting slot is opened briefly, and the inner wall is serpentine. The opening that connects to the mold cavity is tilted downward and small, greatly preventing the liquid material from entering. When the valve rod passes through the extrusion block two, the extrusion block two pushes the valve rod to drive the scraper ring to slide inside the end slot of the venting slot, pushing any liquid material that may have entered the end slot of the venting slot into the mold cavity, so that the liquid material re-participates in the tire forming process during the centrifugation of the PU casting material.

[0042] Meanwhile, both the valve stem and the adjusting rod are supported by elastic elements. After the compression is released, the valve stem and the adjusting rod automatically reset. The venting slots open in stages, and after the venting slots close, the valve stem and the scraper ring automatically clean the end slots of the venting slots. The end slots of the venting slots are distributed in a ring array. The opening time is short and continuous, and venting is carried out in stages at different positions in the mold cavity. This avoids the situation where local air accumulates and cannot be effectively discharged, and avoids the situation where liquid material inside the single hole is always open and splashes into the hole through the venting hole. It also avoids defects such as tire bubbles and pitting caused by local air accumulation. Staged venting can precisely control the timing of venting. Combined with the inclined small opening design, it takes into account both venting efficiency and anti-leakage effect. The periodic cleaning and return function sends the liquid material that has seeped into the venting slot back to the mold cavity to avoid venting channel blockage and ensure long-term stable operation of the mold. At the same time, it improves the utilization rate of raw materials and improves stability in the PU tire production process. Through efficient venting in the PU tire production process, the yield rate of PU tires is improved. Attached Figure Description

[0043] Figure 1 This is a top-view three-dimensional structural diagram of the present invention;

[0044] Figure 2 This is a top view of the three-dimensional structure of the toothed ring of the present invention;

[0045] Figure 3 For the present invention Figure 2 Front view three-dimensional structure diagram;

[0046] Figure 4 This is a top-view three-dimensional structural diagram of the lower mold of the present invention;

[0047] Figure 5 This is a bottom-view perspective view of the three-dimensional structure of the upper mold of the present invention;

[0048] Figure 6 This is a top-view perspective view of the mounting frame structure of the present invention;

[0049] Figure 7 This is a side view of the three-dimensional structure of the toothed plate of the present invention;

[0050] Figure 8 This is a front-view perspective three-dimensional structural diagram of the assembly valve of the present invention;

[0051] Figure 9 This is a side-view perspective view of the assembly valve of the present invention.

[0052] Figure 10 This is a first-angle three-dimensional structural schematic diagram of the assembly valve of the present invention;

[0053] Figure 11 This is a two-dimensional structural schematic diagram of the assembly valve of the present invention, viewed from a main cross-section at a second angle.

[0054] Figure 12 This is a top-view perspective view of the valve stem and adjusting rod of the present invention.

[0055] Figure 13 This is a front-view perspective three-dimensional structural diagram of the valve stem and adjusting rod of the present invention.

[0056] Reference numerals: 1. Base; 2. Mounting frame; 3. Hydraulic rod one; 4. Hydraulic rod two; 5. Guide post; 6. Guide plate; 7. Upper mold; 8. Lower mold; 9. Hollow frame; 10. Motor one; 11. Gear one; 12. Gear ring; 13. Pulley; 14. Raceway; 15. Mounting plate; 16. Support plate; 17. Hydraulic rod three; 18. Ring one; 19. Female buckle; 20. Female buckle; 21. Ring two; 22. Assembly slot; 23. Side frame; 24. Motor two; 25. Battery; 26. Side block; 27. Rotating shaft; 28. Guide rail; 29. 30. Gear plate; 31. Slide groove; 32. Hydraulic rod four; 33. Connecting block; 34. Adjusting shaft; 35. Gear two; 36. Exhaust groove hole; 37. Assembly valve; 38. Butt ring; 39. Adaptor surface; 40. End groove; 41. Sealing seat; 42. Adjusting groove; 43. Starting groove; 44. Valve stem; 45. Adjusting rod; 46. Extrusion block one; 47. Extrusion block two; 48. Ball one; 49. Valve ring; 50. Support ring one; 51. Valve spring; 52. Valve core; 53. Ball two; 54. Support ring two; 55. Spring; 56. Scraper ring. Detailed Implementation

[0057] 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.

[0058] Please see Figures 1 to 13 The present invention provides three embodiments:

[0059] Example 1: A high-efficiency venting centrifugal mold for PU tire production includes a base 1, a mounting frame 2, an upper mold 7, a lower mold 8, a hollow frame 9, an assembly valve 36, a valve stem 43, and an adjusting rod 44. The mounting frame 2 is positioned above the base 1, and an mounting plate 15 is positioned inside the mounting frame 2. The lower mold 8 and the upper mold 7 are positioned above the mounting plate 15. The inner wall of the upper mold 7 has assembly grooves 22 arranged in a circular array and penetrating the internal mold cavity. A columnar assembly valve 36 is positioned inside the assembly grooves 22. The assembly valve 36 has a serpentine venting groove 35 inside. The venting groove 35 includes a serpentine groove section in the middle, an end groove 39 penetrating the mold cavity of the upper mold 7, and a starting groove 42 communicating with the outside. The venting groove 35 has... An adjusting groove 41 is connected to the end groove 39 and one end is connected to the outside. The inner wall of the starting groove 42 is provided with a valve ring 48 and a support ring 49. The valve ring 48 is provided with a conical valve core 51. A valve spring 50 is provided between the valve core 51 and the support ring 49. The inner wall of the adjusting groove 41 is provided with a support ring 53. The adjusting groove 41 is provided with a scraper ring 55 whose sliding path is located inside the end groove 39. A spring 54 is provided between the scraper ring 55 and the support ring 53. One end of the scraper ring 55 is provided with an adjusting rod 44 located inside the support ring 53. A hydraulic rod 17 is provided at the center of the mounting plate 15. A hollow frame 9 is provided at the telescopic end of the hydraulic rod 17. The outer wall of the hollow frame 9 is provided with extrusion blocks 45 and extrusion blocks 46 arranged in a ring array.

[0060] In this embodiment, the power source is motor 10 at the upper end of the mounting plate 15. The output shaft of motor 10 drives gear 11 to rotate. Gear 11 meshes with gear ring 12 at the lower end of the lower mold 8, transmitting driving force to the lower mold 8. The upper mold 7 is locked to the lower mold 8 by snap-fit ​​19 and female snap-fit ​​20, and rotates synchronously with the lower mold 8. The annular pulley 13 on the lower side of the upper mold 7 is rolled in the annular raceway 14 at the upper end of the mounting plate 15, reducing the frictional resistance when the mold rotates and improving the stability of high-speed rotation. The hydraulic rod 4 below the mounting plate 15 drives the support plate 16 to adhere to the bottom of the mounting plate 15, further enhancing the support rigidity of the mold during centrifugation and avoiding eccentric swaying.

[0061] The exhaust core structure is a three-section serpentine exhaust groove 35 inside the assembly valve 36. The middle section of the exhaust groove 35 is a serpentine groove, the end groove 39 that penetrates the mold cavity, and the externally connected starting groove 42. The assembly grooves 22 on the inner wall of the upper mold 7 are arranged in a ring array to ensure full exhaust coverage of the mold cavity. When the mold rotates, the hydraulic rod 17 at the center of the mounting plate 15 drives the hollow frame 9 to be suspended in the annulus 18 of the upper mold 7. The extrusion blocks 45 and 46 on the outer wall of the hollow frame 9 are fixed with the hollow frame 9, while the valve rod 43 and the adjusting rod 44 rotate synchronously with the mold. The ball bearings 47 and 52 at their ends periodically contact the extrusion blocks 45 and 46.

[0062] When the ball 47 is squeezed by the extrusion block 45, the valve stem 43 pushes the conical valve core 51 to compress the valve spring 50. The valve core 51 disengages from the valve ring 48, and the internal channel of the venting slot 35 opens. The gas in the mold cavity is discharged through the end slot 39, the serpentine slot section, and the starting slot 42. The serpentine slot section extends the gas discharge path. The end slot 39, which is connected to the mold cavity, has an opening that is tilted downward and has a very small size. Combined with the sealing effect of the conical valve core 51, it can prevent liquid material from seeping in. After the extrusion block 45 disengages from the ball 47, the rebound force of the valve spring 50 drives the valve core 51 to reset, and the venting slot 35 closes, realizing the periodic opening and staged venting, avoiding liquid material splashing caused by continuous venting.

[0063] When the ball bearing 52 at the end of the adjusting rod 44 contacts the extrusion block 46, the extrusion block 46 pushes the adjusting rod 44 to compress the spring 54, causing the scraper ring 55 to slide in the end groove 39 of the venting hole 35. The sliding path of the scraper ring 55 completely covers the end groove 39, which can scrape off the small amount of PU liquid material that has seeped in and push it back into the mold cavity, realizing the recycling and reuse of liquid material. After the extrusion block 46 separates from the ball bearing 52, the spring 54 drives the adjusting rod 44 and the scraper ring 55 to reset, waiting for the next cleaning cycle. This design avoids blockage of the venting channel, reduces material waste, and ensures long-term stable operation of the mold.

[0064] The hydraulic rod 3 at the top of the base 1 drives the mounting frame 2 to move longitudinally, and the guide plate 6 slides along the guide post 5 to achieve guidance, which can adapt to the height requirements of different work positions. The motor 24, powered by the battery 25, drives the rotating shaft 27 to rotate, which drives the side block 26 to rotate the upper mold 7. With the snap-fit ​​structure of the male buckle 19 and the female buckle 20, the mold can be opened and closed automatically. The hydraulic rod 31 drives the toothed plate 29 to slide along the guide rail 28. The toothed plate 29 meshes with the gear 34 on the outer wall of the adjusting shaft 33, which drives the adjusting shaft 33 to rotate, thereby adjusting the tilt angle between the mounting plate 15 and the mold, which is suitable for pre-treatment processes such as mold release agent spraying and automated cleaning.

[0065] Start hydraulic rod 431 to adjust the mold tilt angle, and use automated cleaning equipment to thoroughly clean the upper and lower mold cavities to remove residual material and release agent. After cleaning, reset the tilt angle to ensure that the inner wall of the mold cavity is smooth and free of impurities.

[0066] Apply release agent evenly to the inner wall of the upper and lower mold cavity 8, start the mold preheating system, which is integrated inside the mold body, raise the mold cavity temperature to 45-55℃ and keep it at that temperature for 10-15 minutes to improve the fluidity and curing consistency of the PU material, ensure that the serpentine venting groove 35 is unobstructed, the scraper ring 55 slides flexibly, and the valve core 51 and valve ring 48 are well sealed. Fix the assembly valve 36 in the sealing seat 40 through the mounting hole of the mating ring 37 to ensure that the mating surface 38 of the assembly valve 36 is completely in contact with the arc surface of the inner wall of the upper mold cavity 7, without interfering with tire molding;

[0067] The starter motor 24 drives the upper mold 7 to flip and close onto the lower mold 8. The male buckle 19 and female buckle 20 automatically engage and lock, ensuring a tight seal at the parting surface. The hydraulic rod 4 is activated, driving the support plate 16 to support the mounting plate 15 upwards, enhancing the overall rigidity of the mold.

[0068] Mix polyurethane prepolymer, curing agent, catalyst and filler according to the formula, stir evenly to obtain PU casting material, slowly inject the mixed PU casting material along the edge of the cavity of the lower mold 8, leave space for centrifugal molding and curing shrinkage, start hydraulic rod three 17, push the hollow frame 9 to the working position inside the ring one 18.

[0069] Start motor 10 and operate according to the process of "low speed start (300-500 r / min) → uniform speed acceleration → stable high speed (1200-1800 r / min)". The mold rotates synchronously under the meshing action of gear 11 and gear ring 12. Under the action of centrifugal force, the PU material is evenly attached to the inner wall of the mold cavity, initially forming the tire tread and tire body structure. During the high-speed rotation of the mold, valve rod 43 and adjusting rod 44 rotate synchronously with the mold. Ball bearing 1 47 and ball bearing 2 52 periodically contact extrusion block 1 45 and extrusion block 2 46. For each rotation, the exhaust slot 35 opens 8 times, with each opening lasting 0.2-0.5 seconds. Air and gases such as carbon dioxide produced by chemical reaction in the mold cavity are quickly discharged through the serpentine exhaust groove 35. At the same time, the scraper ring 55 slides periodically to push the residual liquid in the end groove 39 back into the mold cavity. During centrifugation, the height of the mounting frame 2 is finely adjusted by the hydraulic rod 3 to ensure the coaxiality of the mold rotation. The exhaust gas discharge status is monitored in real time. The position of the hollow frame 9 is finely adjusted by the hydraulic rod 17 to optimize the contact force between the extrusion block and the valve rod 43 and the adjusting rod 44. After curing, the motor 10 is turned off. After the mold stops rotating, the motor 24 is started to open the upper mold 7. The hydraulic rod 3 is started to lower the height of the mounting frame 2 to facilitate the removal of the tire blank.

[0070] The tire blank is trimmed and polished to remove residual material and burrs from the parting surface. The tire appearance is inspected for pitting, bubbles, dimensional accuracy, and hardness. Once qualified, it is a finished product. The cavities of the upper and lower molds 8 and assembly valve 36 are cleaned to remove residual PU material and release agent. The wear of components such as the venting slot 35, scraper ring 55, and valve core 51 is checked, and replacement or maintenance is performed as necessary. The hydraulic rod 17 is activated to retract the hollow frame 9 into the annulus 21 of the lower mold 8. At the same time, the mounting plate 15 rotates, and the upper mold 7 and lower mold 8 open. As needed, an independent cleaning and release agent device is set on one side of the mounting frame 2. The mold cavity is cleaned by the corresponding cleaning spray device, and the release agent is automatically sprayed when the release agent is applied to facilitate the preparation of the mold for reuse. The angle adjustment and lifting of the mold improve the extensibility of the equipment.

[0071] Example 2:

[0072] The upper end of the base 1 is provided with a hydraulic rod 3 connected to the lower end of the mounting frame 2. The upper ends of the base 1 are provided with symmetrically distributed guide posts 5 on both sides. The two ends of the mounting frame 2 are provided with guide plates 6 that are slidably sleeved on the outer wall of the guide posts 5.

[0073] A support plate 16 is provided below the mounting plate 15, and a hydraulic rod 4 with a telescopic end connected to the lower end of the support plate 16 is provided inside the mounting frame 2.

[0074] The upper mold 7 has a male buckle 19 at one end, and the lower mold 8 has a female buckle 20 at one end that is locked to the male buckle 19. The lower mold 8 has a mounting frame 2 at one end, and a motor 24 and a battery 25 are mounted at one end of the mounting frame 2. The output end of the motor 24 has a rotating shaft 27 that is rotatably mounted inside the mounting frame 2. The outer wall of the rotating shaft 27 is fitted with a side block 26 that is connected to the upper mold 7.

[0075] A motor 10 is provided on one side of the upper end of the mounting plate 15. A gear 11 is provided at the output end of the motor 10. A gear ring 12 that meshes with the gear 11 is provided at the lower end of the lower mold 8. A ring-shaped raceway 14 is provided on the upper side of the mounting plate 15. A ring-shaped pulley 13 that is rolled inside the raceway 14 is provided on the lower side of the upper mold 7.

[0076] In this embodiment, two guide pillars 5 are symmetrically arranged on the upper end of the base 1, and the guide plates 6 at both ends of the mounting frame 2 are slidably sleeved on the outer wall of the guide pillars 5; a hydraulic rod 3 is installed at the center of the upper end of the base 1, and its telescopic end is fixedly connected to the lower end of the mounting frame 2, which can drive the mounting frame 2 to move longitudinally along the guide pillars 5 to realize the overall height adjustment of the mold and adapt to the docking requirements of different production stations. A horizontal support plate 16 is set below the mounting plate 15, and a hydraulic rod 4 is symmetrically installed on both sides inside the mounting frame 2. The telescopic end of the hydraulic rod 4 is fixed to the lower end of the support plate 16; before the mold rotates centrifugally, the hydraulic rod 4 drives the support plate 16 to move upward until it is tightly attached to the lower end of the mounting plate 15 to form a rigid support at the bottom, so as to avoid deformation or eccentric shaking of the mounting plate 15 during high-speed rotation;

[0077] The upper mold 7 has a protruding male buckle 19 at one end, and the lower mold 8 has a corresponding female buckle 20. The male buckle 19 and the female buckle 20 can be locked together to achieve mold closing and sealing. A small mounting frame 2 is fixedly installed at one end of the lower mold 8. The mounting frame 2 integrates a second motor 24 and a battery 25. The output end of the second motor 24 is connected to a rotating shaft 27. A side block 26 is sleeved on the outer wall of the rotating shaft 27. The side block 26 is fixedly connected to the side wall of the upper mold 7. The second motor 24 is powered by the battery 25 and can drive the rotating shaft 27. 7 drives the side block 26 to flip, realizing the automatic opening and closing of the upper mold 7. The motor 10 is fixedly installed on one side of the upper end of the mounting plate 15. The output shaft of the motor 10 is fitted with gear 11. The lower end face of the lower mold 8 is fixedly installed with an annular gear ring 12. The gear ring 12 meshes with the gear 11 for transmission. An annular raceway 14 is opened on the upper side of the mounting plate 15. An annular array of pulleys 13 is installed on the lower side of the upper mold 7. The pulleys 13 roll and embed into the raceway 14 to form an auxiliary support and guide structure.

[0078] Start motor 24, which drives shaft 27 to rotate side block 26. Upper mold 7 opens upward with side block 26. Adjust the tilt angle of mounting plate 15 using hydraulic rod 31. Clean the cavities of upper and lower molds 8 with cleaning equipment. Then reset the tilt angle, apply release agent evenly to the inner wall of the cavity, preheat to 45-55℃ and keep warm. Slowly inject the evenly mixed PU casting material into the cavity of lower mold 8, with a casting volume of 92%-95% of the cavity volume. Start motor 24 to rotate in the opposite direction, driving upper mold 7 to cover lower mold 8. Male buckle 19 and female buckle 20 automatically engage and lock to ensure sealing of the parting surface. Start hydraulic rod 4, driving support plate 16 to support mounting plate 15 upward, completing mold reinforcement.

[0079] Centrifugal molding drive: Start motor 10, the output shaft of motor 10 drives gear 11 to rotate, gear 11 drives gear ring 12 to rotate through meshing, thereby driving the lower mold 8 and the upper mold 7 to rotate synchronously. The pulley 13 at the lower end of the upper mold 7 rolls along the annular raceway 14 of the mounting plate 15 to reduce rotational friction resistance and limit the lateral displacement of the mold, ensuring coaxiality during high-speed rotation; according to the tire specifications, the mold speed is adjusted to 1200-1600 r / min, and the PU casting material is evenly adhered to the inner wall of the mold cavity under the action of centrifugal force to form the tire tread and tire body structure;

[0080] During mold rotation, extrusion blocks 45 and 46 on the hollow frame 9 periodically extrude valve rod 43 and adjusting rod 44, achieving phased venting and cleaning of the venting groove. The specific venting and cleaning mechanism is the same as the core working principle. The rotation continues until the PU material is completely cured, with the curing time controlled at 18-25 minutes. After curing, motor 10 is turned off, and the mold stops rotating completely. Hydraulic rod 4 is started to drive support plate 16 to reset downwards. Motor 24 is started to drive upper mold 7 to open, and tire blank is removed. Finally, hydraulic rod 3 is started to drive mounting frame 2 downwards. Reset to complete a single production cycle. Gear 11 meshes with gear ring 12, and pulley 13 and raceway 14 guide the mold to ensure smooth rotation, avoid eccentric vibration, and improve tire size accuracy. Hydraulic rod 24 drives support plate 16 for enhanced support, which can withstand centrifugal stress caused by high-speed rotation and reduce mold wear. Motor 24 drives automatic opening and closing structure with male buckle 19 and female buckle 20 for locking, which is convenient and efficient to operate, reduces manual intervention, and improves production efficiency. The height adjustment structure composed of hydraulic rod 13 and guide column 5 has strong adaptability and can be flexibly connected with different production line equipment.

[0081] Example 3:

[0082] The upper mold 7 has a first ring 18 inside, the lower mold 8 has a second ring 21 inside, the hollow frame 9 is suspended inside the first ring 18 and stored inside the second ring 21 after use, and one end of the adjusting rod 44 and the valve rod 43 is located inside the side of the first ring 18.

[0083] The valve stem 43 is located inside the ring 18 and one end is rotatably mounted with a ball 47. The adjusting rod 44 is located inside the ring 18 and one end is rotatably mounted with a ball 52. The extrusion block 45 will extrude the rotating ball 47, and the extrusion block 46 will extrude the rotating ball 52. The extrusion block 45 and the ball 47 are located on the same horizontal plane, and the extrusion block 46 and the ball 52 are located on the same horizontal plane. The extrusion block 45 is located above the extrusion block 46.

[0084] The inner wall of the assembly groove 22 is provided with a sealing seat 40, and the assembly valve 36 is slidably installed inside the sealing seat 40. After the assembly valve 36 is assembled inside the sealing seat 40, one end is provided with a mating surface 38 that matches the arc surface of the inner wall of the upper mold cavity 7.

[0085] The inner wall of the ring core 18 is provided with a docking ring 37 located at the opening of the assembly groove 22, and the outer wall of the assembly valve 36 is provided with a docking ring 37. The inner side of the docking ring 37 is provided with mounting holes distributed in a ring array.

[0086] Both ends of the mounting plate 15 are provided with adjusting shafts 33 inside the rotating mounting side frame 23. Gear 2 34 is sleeved on the outer wall of the adjusting shaft 33. Hydraulic rod 4 31 is provided on the inner wall of one side of the side frame 23. A connecting block 32 is provided at the telescopic end of the hydraulic rod 4 31. A toothed plate 29 that meshes with gear 2 34 is provided at the upper end of the connecting block 32. A sliding groove 30 is opened at one end of the toothed plate 29. A guide rail 28 that is slidably installed inside the sliding groove 30 is provided on the inner wall of the side frame 23.

[0087] In this embodiment, the upper mold 7 has a first ring 18 inside, and the lower mold 8 has a second ring 21 inside. The hollow frame 9 driven by the hydraulic rod 3 17 is suspended in the first ring 18 when working, and is stored in the second ring 21 when idle, ensuring that the rotation of the mold and the hollow frame 9 do not interfere with each other. One end of the valve rod 43 and the adjusting rod 44 extends into the first ring 18. The end of the valve rod 43 is rotatably installed with a first ball 47, and the end of the adjusting rod 44 is rotatably installed with a second ball 52. The first ball 47 and the extrusion block 45 on the outer wall of the hollow frame 9 are on the same horizontal plane, and the second ball 52 and the extrusion block 46 are on the same horizontal plane. The extrusion block 45 is vertically located above the extrusion block 46, realizing the orderly linkage of the venting and cleaning actions.

[0088] A sealing seat 40 is installed on the inner wall of the assembly groove 22 of the upper mold 7. The columnar assembly valve 36 is slidably assembled in the sealing seat 40 to ensure the sealing of the assembly. One end of the assembly valve 36 is provided with an adapter surface 38, which is completely fitted with the arc surface of the inner wall of the upper mold cavity, without affecting the tire forming accuracy. The inner wall of the ring core 18 and the outer wall of the assembly valve 36 are both provided with docking rings 37. The docking rings 37 are provided with mounting holes arranged in a ring array on the side. The assembly valve 36 is firmly fixed by fasteners through the mounting holes to avoid loosening during centrifugation. The adjusting shaft 33 is rotatably installed in the side frame 23 at both ends of the mounting plate 15. The outer wall of the adjusting shaft 33 is sleeved with gear 2 34. A hydraulic rod 4 31 is installed on one inner wall of the side frame 23. Its telescopic end is connected to the connecting block 32. The upper end of the connecting block 32 is fixed with a toothed plate 29 that meshes with gear 2 34. One end of the toothed plate 29 is provided with a sliding groove 30. The guide rail 28 on the inner wall of the side frame 23 is slidably embedded in the sliding groove 30 to form a guide structure to ensure that the toothed plate 29 moves smoothly.

[0089] Start hydraulic rod 31, driving connecting block 32 to slide toothed plate 29 along guide rail 28. Toothed plate 29 meshes with drive gear 34 to rotate, thereby driving adjusting shaft 33 and mounting plate 15 to rotate synchronously, adjusting mold to preset tilt angle. Clean mold cavity using automated cleaning equipment, then reverse hydraulic rod 31 to reset tilt angle, evenly apply release agent to inner wall of mold cavity, slide assembly valve 36 into sealing seat 40, so that mating surface 38 fits against inner wall of mold cavity, and connects through mating ring 37. The mounting holes are secured with fasteners. The second motor 24 drives the upper mold 7 to close, and the male buckle 19 and female buckle 20 are locked together. The second hydraulic rod 4 is activated, driving the support plate 16 to support the mounting plate 15 upward, thus completing the mold reinforcement. The uniformly mixed PU casting material is slowly injected into the cavity of the lower mold 8, and the hollow frame 9 is pushed to the working position of the ring center 18. The first motor 10 is activated, and the mold is driven to rotate through the meshing of the gear 11 and the gear ring 12. The PU material adheres to the mold cavity and is formed under the action of centrifugal force.

[0090] When the mold rotates, the valve rod 43 and the adjusting rod 44 rotate synchronously with it. The first ball 47 periodically contacts the first extrusion block 45. The extrusion valve rod 43 pushes the valve core 51 to compress the valve spring 50, and the exhaust slot 35 opens. The gas is discharged through the serpentine slot section. Then the second ball 52 contacts the second extrusion block 46, pushing the adjusting rod 44 to drive the scraper ring 55 to clean the residual liquid in the end slot 39 and push it back into the mold cavity. After the extrusion block is disengaged, the valve spring 50 and the spring 54 drive the valve core 51 and the scraper ring 55 to reset respectively, realizing periodic exhaust and cleaning. The rotation state is maintained until the PU material is completely cured. The first motor 10 is turned off. After the mold stops, the second hydraulic rod 4 is started to retract the support plate 16. The second motor 24 is started to open the upper mold 7 and take out the tire blank. Finally, the third hydraulic rod 17 is started to store the hollow frame 9 into the ring core 21, completing the production cycle.

[0091] The rolling contact design between the ball bearings and the extrusion block significantly reduces transmission friction and resistance, improving the response accuracy and structural lifespan of the venting and cleaning actions. The dual design of the sealing seat 40 and the docking ring 37 ensures both assembly sealing and stable fixation of the assembly valve 36, preventing displacement caused by centrifugal vibration. The precise tilt adjustment structure can flexibly adapt to different pretreatment processes such as mold release agent spraying and automated cleaning, improving the equipment's versatility. The orderly linkage of venting and cleaning actions ensures sufficient venting while effectively preventing venting channel blockage, further improving the tire yield.

[0092] A method for using a high-efficiency venting centrifugal mold for PU tire production includes the following steps:

[0093] S1. Mold Pretreatment

[0094] Mold cleaning and tilt angle adjustment: Start hydraulic rod 4 31, drive adjustment shaft 33 to rotate through tooth plate 29 and gear 2 34 to adjust the tilt angle of mounting plate 15 and mold, adapt to automated cleaning equipment; open upper mold 7, thoroughly clean the mold cavity of upper mold 7 and lower mold 8 to remove residual material residue, solidified liquid and impurities, and ensure smooth inner wall of mold cavity;

[0095] Applying release agent and preheating: After cleaning, reverse the hydraulic rod 431 to reset the mold tilt angle; apply release agent evenly to the inner wall of the mold cavity to prevent the PU material from sticking after curing; start the mold preheating system to raise the mold cavity temperature to 45-55℃ and keep it at that temperature for 10-15 minutes to improve the fluidity of the PU material and ensure molding quality;

[0096] Assembly valve inspection and fixing: Confirm that the serpentine exhaust groove 35 in the assembly valve 36 is unobstructed and that the valve core 51 and scraper ring 55 slide flexibly; slide the assembly valve 36 into the assembly groove 22 of the upper mold 7, and lock it with fasteners through the mounting hole of the mating ring 37 to ensure that the mating surface 38 is completely in contact with the arc surface of the inner wall of the mold cavity, and the sealing seat 40 achieves sealing at the assembly point.

[0097] S2, Mold Closure and Casting

[0098] Mold Closure and Locking: Start motor 24, powered by battery 25, drives shaft 27 to rotate side block 26, and the upper mold 7 closes onto the lower mold 8 with side block 26; the male buckle 19 and female buckle 20 are locked together to ensure a tight seal on the parting surface and prevent liquid leakage during centrifugation;

[0099] Mold support reinforcement: Start hydraulic rod 4 to drive support plate 16 to move upward until it is tightly attached to the lower end of mounting plate 15, forming a rigid bottom support to prevent the mold from eccentric shaking or deformation during high-speed rotation.

[0100] PU casting material injection: Mix polyurethane prepolymer, curing agent, catalyst and filler according to the formula, and stir evenly to form PU casting material (control the speed and time during stirring to reduce air mixing); slowly inject the mixed PU casting material along the edge of the lower mold cavity 8, the pouring volume is 92%-95% of the cavity volume, and leave space for centrifugal molding and curing shrinkage.

[0101] S3, Centrifugal molding and core function operation (exhaust, channel self-cleaning)

[0102] Hollow frame in place: Start the hydraulic rod 3 17 in the center of the mounting plate 15 to drive the hollow frame 9 to move upward and suspend it in the annulus 18 of the upper mold 7, ensuring that the extrusion block 1 45 and extrusion block 2 46 on the outer wall of the hollow frame 9 are at the same level as the ball end of the valve rod 43 and the adjusting rod 44.

[0103] Start centrifugal rotation: Start motor 10, whose output shaft drives gear 11 to rotate, which in turn drives the lower mold 8 to rotate through meshing with gear ring 12. The upper mold 7 rotates synchronously with the lower mold 8. The pulley 13 at the lower end of the upper mold 7 rolls along the raceway 14 of the mounting plate 15 to reduce rotational friction. Adjust the speed according to the process of "low speed start (300-500r / min), uniform speed acceleration, and stable high speed (1200-1800r / min)". Under the action of centrifugal force, the PU material is evenly attached to the inner wall of the mold cavity to form the tire tread and tire body structure.

[0104] Staged venting (automatic linkage): When the mold rotates, the valve rod 43 and the adjusting rod 44 rotate synchronously with the mold. The first ball 47 and the second ball 52 at their ends periodically contact the extrusion blocks 45 and 46 of the hollow frame 9. When the first ball 47 is squeezed by the extrusion block 45, the valve rod 43 pushes the conical valve core 51 to compress the valve spring 50. The valve core 51 disengages from the valve ring 48, and the venting slot 35 opens. The air and gas generated by the chemical reaction in the mold cavity are discharged through the end slot 39, the serpentine slot section, and the starting slot 42. After the extrusion block 45 disengages, the valve spring 50 drives the valve core 51 to reset, and the venting slot 35 closes, realizing staged venting of "opening 8 times per revolution, each time for 0.2-0.5 seconds", avoiding liquid splashing.

[0105] Self-cleaning of the exhaust channel and recovery of liquid material: When the second ball 52 is squeezed by the second extrusion block 46, the adjusting rod 44 compresses the spring 54, which drives the scraper ring 55 to slide in the end groove 39, scraping off the small amount of PU liquid material that has seeped in and pushing it back into the mold cavity, thus realizing the recovery of raw materials; after the second extrusion block 46 is disengaged, the spring 54 drives the scraper ring 55 and the adjusting rod 44 to reset, thus avoiding blockage of the exhaust channel;

[0106] Centrifugation process fine-tuning: The height of the mounting frame 2 is fine-tuned by hydraulic rod 13 to ensure the coaxiality of the mold rotation; the gas discharge status of the exhaust port is monitored in real time, and the position of the hollow frame 9 is fine-tuned by hydraulic rod 317 to optimize the contact force between the extrusion block and the valve rod 43 and the adjusting rod 44, so as to ensure the exhaust and cleaning effect;

[0107] Curing wait: Keep rotating at high speed until the PU material is completely cured. The curing time is adjusted according to the formula and temperature, and is usually controlled within 18-25 minutes.

[0108] S4. Mold opening, part removal, and finished product processing

[0109] Stop rotation and reset support: Turn off motor 10. After the mold has completely stopped rotating, start hydraulic rod 4 to drive support plate 16 to reset downwards and release the bottom support.

[0110] Mold opening: Start motor 24 rotates in reverse, driving the upper mold 7 to flip upward and open; drive the mounting frame 2 to move downward along the guide post 5 via hydraulic rod 3, lowering the mold height for easier part removal;

[0111] Remove the blank and process the finished product: Remove the tire blank, trim and grind it to remove residual material and burrs from the parting surface; inspect the tire appearance (no pits or bubbles), dimensional accuracy and hardness, and it is a finished product after passing the inspection.

[0112] The above specific embodiments are merely several preferred embodiments of the present invention. Based on the technical solutions of the present invention and the relevant teachings of the above embodiments, those skilled in the art can make various alternative improvements and combinations to the above specific embodiments.

[0113] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A high-efficiency exhaust centrifugal mold for PU tire production, comprising a base (1), a mounting frame (2), an upper mold (7), a lower mold (8), a hollow frame (9), an assembly valve (36), a valve stem (43), and an adjusting rod (44), characterized in that, A mounting frame (2) is provided above the base (1). A mounting plate (15) is provided inside the mounting frame (2). A closed lower mold (8) and an upper mold (7) are provided above the mounting plate (15). An assembly groove (22) is provided on the inner wall of the upper mold (7) in a ring array and penetrating the inner cavity. A columnar assembly valve (36) is provided inside the assembly groove (22). A serpentine venting slot (35) is provided inside the assembly valve (36). The venting slot (35) includes a serpentine slot section in the middle, an end slot (39) penetrating the cavity of the upper mold (7), and a starting slot (42) communicating with the outside. An adjustment slot (41) is provided inside the venting slot (35) communicating with the end slot (39) and having one end connected to the outside. A valve ring (48) is provided on the inner wall of the starting slot (42). The valve ring (48) is provided with a conical valve core (51) inside the support ring (49), and a valve spring (50) is provided between the valve core (51) and the support ring (49). The inner wall of the adjustment groove (41) is provided with a support ring (53). The sliding path of the scraper ring (55) is located inside the end groove (39) inside the adjustment groove (41). A spring (54) is provided between the scraper ring (55) and the support ring (53). One end of the scraper ring (55) is provided with an adjustment rod (44) located inside the support ring (53). The center of the mounting plate (15) is provided with a hydraulic rod (17). The telescopic end of the hydraulic rod (17) is provided with a hollow frame (9). The outer wall of the hollow frame (9) is provided with an extrusion block (45) and an extrusion block (46) arranged in a ring array.

2. The high-efficiency exhaust centrifugal mold for PU tire production according to claim 1, characterized in that, The upper end of the base (1) is provided with a hydraulic rod (3) connected to the lower end of the mounting frame (2). The upper ends of the base (1) are provided with symmetrically distributed guide posts (5). The two ends of the mounting frame (2) are provided with guide plates (6) that are slidably sleeved on the outer wall of the guide posts (5).

3. The high-efficiency exhaust centrifugal mold for PU tire production according to claim 1, characterized in that, A support plate (16) is provided below the mounting plate (15), and a hydraulic rod (4) with its telescopic end connected to the lower end of the support plate (16) is provided inside the mounting frame (2).

4. The high-efficiency exhaust centrifugal mold for PU tire production according to claim 1, characterized in that, The upper mold (7) has a first ring (18) inside, the lower mold (8) has a second ring (21) inside, the hollow frame (9) is suspended inside the first ring (18) and stored inside the second ring (21) after use, and one end of the adjusting rod (44) and the valve rod (43) is located inside the side of the first ring (18).

5. A high-efficiency exhaust centrifugal mold for PU tire production according to claim 4, characterized in that, The valve stem (43) is rotatably mounted with a ball bearing (47) at one end inside the first ring (18), and the adjusting rod (44) is rotatably mounted with a ball bearing (52) at one end inside the first ring (18). The first extrusion block (45) will extrude the rotating ball bearing (47), and the second extrusion block (46) will extrude the rotating ball bearing (52). The first extrusion block (45) and the ball bearing (47) are on the same horizontal plane, and the second extrusion block (46) and the ball bearing (52) are on the same horizontal plane. The first extrusion block (45) is located above the second extrusion block (46).

6. The high-efficiency exhaust centrifugal mold for PU tire production according to claim 1, characterized in that, The inner wall of the assembly groove (22) is provided with a sealing seat (40), and the assembly valve (36) is slidably installed inside the sealing seat (40). After the assembly valve (36) is assembled inside the sealing seat (40), one end is provided with a mating surface (38) that matches the arc surface of the inner wall of the upper mold cavity (7).

7. A high-efficiency exhaust centrifugal mold for PU tire production according to claim 4, characterized in that, The inner wall of the ring core (18) is provided with a docking ring (37) located at the opening of the assembly groove (22), and the outer wall of the assembly valve (36) is provided with a docking ring (37). The inner side of the docking ring (37) is provided with mounting holes arranged in a ring array.

8. A high-efficiency exhaust centrifugal mold for PU tire production according to claim 1, characterized in that, The upper mold (7) is provided with a female buckle (19) at one end, and the lower mold (8) is provided with a female buckle (20) that is engaged and locked with the female buckle (19) at one end. The lower mold (8) is provided with a mounting frame (2) at one end. The mounting frame (2) is provided with a second motor (24) and a battery (25) at one end. The output end of the second motor (24) is provided with a rotating shaft (27) that is rotatably installed inside the mounting frame (2). The outer wall of the rotating shaft (27) is sleeved with a side block (26) that is connected to the upper mold (7).

9. A high-efficiency exhaust centrifugal mold for PU tire production according to claim 1, characterized in that, A motor (10) is provided on one side of the upper end of the mounting plate (15), and a gear (11) is provided at the output end of the motor (10). A gear ring (12) that meshes with the gear (11) is provided at the lower end of the lower mold (8). A ring-shaped raceway (14) is provided on the upper side of the mounting plate (15), and a ring-shaped pulley (13) that is rolled inside the raceway (14) is provided on the lower side of the upper mold (7). Adjustment mechanisms are provided inside the rotating mounting side frame (23) at both ends of the mounting plate (15). The adjusting shaft (33) has a gear two (34) sleeved on its outer wall. The inner wall of one side of the side frame (23) is provided with a hydraulic rod four (31). The hydraulic rod four (31) has a connecting block (32) at its telescopic end. The upper end of the connecting block (32) is provided with a toothed plate (29) that meshes with the gear two (34). One end of the toothed plate (29) is provided with a sliding groove (30). The inner wall of the side frame (23) is provided with a guide rail (28) that is slidably installed inside the sliding groove (30).

10. A method of using a high-efficiency exhaust centrifugal mold for PU tire production according to any one of claims 1-9, characterized in that, Includes the following steps: S1. Mold Pretreatment Mold cleaning and tilt angle adjustment: Start hydraulic rod four (31), drive the adjustment shaft (33) to rotate through the meshing of tooth plate (29) and gear two (34), adjust the tilt angle of mounting plate (15) and mold, and adapt to automated cleaning equipment; open the upper mold (7), thoroughly clean the mold cavity of the upper mold (7) and lower mold (8), remove residual material residue, solidified liquid and impurities, and ensure that the inner wall of the mold cavity is smooth; Applying release agent and preheating: After cleaning, reverse the hydraulic rod four (31) to reset the mold tilt angle; apply release agent evenly to the inner wall of the mold cavity; start the mold preheating system to raise the mold cavity temperature to 45-55℃ and keep it warm for 10-15 minutes; Inspection and fixing of assembly valve: Confirm that the serpentine exhaust groove (35) in the assembly valve (36) is unobstructed and that the valve core (51) and scraper ring (55) slide flexibly; slide the assembly valve (36) into the assembly groove (22) of the upper mold (7), and lock it with fasteners through the mounting hole of the mating ring (37) to ensure that the mating surface (38) is completely in contact with the arc surface of the inner wall of the mold cavity, and the sealing seat (40) achieves sealing at the assembly point; S2, Mold Closure and Casting Mold closing and locking: Start motor two (24), powered by battery (25) to drive shaft (27) to rotate side block (26), and the upper mold (7) covers the lower mold (8) with side block (26); the male buckle (19) and female buckle (20) are locked together to ensure tight sealing of the parting surface and prevent liquid leakage during centrifugation; Mold support reinforcement: Start hydraulic rod two (4) to drive the support plate (16) to move upward until it is tightly attached to the lower end of the mounting plate (15) to form a rigid bottom support, so as to avoid the mold from eccentric shaking or deformation when rotating at high speed; PU casting material injection: Mix polyurethane prepolymer, curing agent, catalyst and filler according to the formula, stir evenly to form PU casting material; slowly inject the mixed PU casting material along the edge of the cavity of the lower mold (8), the injection volume is 92%-95% of the cavity volume, and reserve space for centrifugal molding and curing shrinkage; S3, Centrifugal Molding and Core Function Operation Hollow frame in place: Start the hydraulic rod three (17) in the center of the mounting plate (15) to drive the hollow frame (9) to move upward and suspend it in the annulus one (18) of the upper mold (7), ensuring that the extrusion block one (45), extrusion block two (46) on the outer wall of the hollow frame (9) are at the same level as the ball end of the valve rod (43) and the adjusting rod (44); Start centrifugal rotation: Start motor one (10), its output shaft drives gear one (11) to rotate, and drives the lower mold (8) to rotate by meshing with the gear ring (12), and the upper mold (7) rotates synchronously with the lower mold (8); the pulley (13) at the lower end of the upper mold (7) rolls along the raceway (14) of the mounting plate (15) to reduce rotational friction; adjust the speed according to the process of "low speed start, uniform speed acceleration, stable high speed", and the PU material is evenly attached to the inner wall of the mold cavity under the action of centrifugal force to form the tire tread and tire body structure; (Stage venting): When the mold rotates, the valve rod (43) and the adjusting rod (44) rotate synchronously with the mold, and the ball bearings 1 (47) and 2 (52) at their ends periodically contact the extrusion blocks 1 (45) and 2 (46) of the hollow frame (9): When the first ball (47) is squeezed by the first extrusion block (45), the valve stem (43) pushes the conical valve core (51) to compress the valve spring (50), the valve core (51) disengages from the valve ring (48), the venting slot (35) opens, and the air and gas generated by the chemical reaction in the mold cavity are discharged through the end slot (39), the serpentine slot section, and the starting slot (42); after the first extrusion block (45) disengages, the valve spring (50) drives the valve core (51) to reset, and the venting slot (35) closes, realizing the staged venting of "opening 8 times per revolution, each time for 0.2-0.5s", avoiding liquid splashing; Self-cleaning of exhaust channel and liquid material recovery: When the second ball (52) is squeezed by the second extrusion block (46), the adjusting rod (44) compresses the spring (54), which drives the scraper ring (55) to slide in the end groove (39), scraping off the small amount of PU liquid material that has seeped in and pushing it back into the mold cavity, thus realizing the recovery of raw materials; after the second extrusion block (46) is disengaged, the spring (54) drives the scraper ring (55) and the adjusting rod (44) to reset, thus avoiding blockage of the exhaust channel; Centrifugation process fine-tuning: Fine-tune the height of the mounting frame (2) by hydraulic rod one (3) to ensure the coaxiality of the mold rotation; monitor the gas discharge status of the exhaust port in real time, fine-tune the position of the hollow frame (9) by hydraulic rod three (17), optimize the contact force between the extrusion block and the valve rod (43) and the adjusting rod (44), and ensure the exhaust and cleaning effect; Curing wait: Keep rotating at high speed until the PU material is completely cured. The curing time is adjusted according to the formula and temperature, and is usually controlled within 18-25 minutes. S4. Mold opening, part removal, and finished product processing Stop rotation and reset support: Turn off motor one (10), and after the mold has completely stopped rotating, start hydraulic rod two (4) to drive support plate (16) to reset downward and release bottom support; Mold opening: Start motor two (24) to rotate in the opposite direction, driving the upper mold (7) to flip upward and open; drive the mounting frame (2) to move downward along the guide post (5) through hydraulic rod one (3) to reduce the height of the mold and facilitate the removal of parts; Remove the blank and process the finished product: Remove the tire blank, trim and grind it to remove residual material and burrs from the parting surface; inspect the tire's appearance, dimensional accuracy and hardness, and if it passes the inspection, it is a finished product.

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