Uniform silicone rubber injection mold with spiral runner
By introducing a spiral flow channel and a vacuum exhaust system into the silicone rubber injection mold, the problems of uneven material filling and untimely exhaust in traditional molds have been solved, enabling high-quality and high-performance production of the products.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-11
- Publication Date
- 2026-03-10
AI Technical Summary
Traditional silicone rubber injection molds have shortcomings in material filling and venting, which can lead to problems such as air bubbles inside the product and poor interfacial bonding.
A uniform silicone rubber injection mold with a spiral flow channel is used, combined with a vacuum pump, solenoid valve and pressure sensor. Through the spiral flow channel design and vacuum exhaust system, uniform flow of melt and efficient exhaust are achieved, ensuring that the gas in the mold cavity is discharged in time.
It improves the appearance quality and mechanical properties of the product, reduces bubble generation, enhances the bonding strength between the melt and the mold cavity wall, and improves the density uniformity and quality stability of the product.
Smart Images
Figure CN223982090U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of injection molding technology, and in particular to a uniform silicone rubber injection mold with a spiral flow channel. Background Technology
[0002] Silicone rubber injection molds are tools used for molding silicone rubber and are crucial in the production of silicone rubber products. They are used to inject molten silicone rubber into a specific cavity, which is then cooled and solidified to form the desired silicone rubber product.
[0003] The basic structure of a silicone rubber injection mold consists of two main parts: a fixed mold and a moving mold. The fixed mold is fixed on the injection molding machine's fixed plate and mainly includes a sprue bushing and a positioning ring, used for injecting high-temperature solid silicone rubber and positioning the mold. The moving mold is connected to the injection molding machine's moving plate and is equipped with a core and an ejection mechanism, responsible for shaping the internal parts of the molded product and demolding the product. The working principle is that the injection molding machine heats and melts the silicone rubber raw material, which is then injected into the mold's sprue bushing through the nozzle. The melt enters the cavity along the runner, and after filling the cavity, it is held under pressure and cooled. Once the silicone rubber has cooled and solidified, the moving mold retracts, and the ejection mechanism pushes the molded product out of the mold, completing one injection molding process.
[0004] However, traditional silicone rubber injection molds have certain shortcomings in material filling and venting. In terms of venting, traditional silicone rubber injection molds mainly rely on natural venting methods such as parting line gap and ejector pin gap. These natural venting channels are prone to problems such as uneven local pressure and obstructed gas flow paths, which cannot effectively and timely expel air from the cavity. From the perspective of material filling, traditional silicone rubber injection molds usually adopt a straight flow channel design. When high-temperature solid silicone rubber flows in such a flow channel, uneven flow velocity is likely to occur. Due to the large difference in flow velocity between the center and the edge of the flow channel, the melt reaches different positions in the cavity at different times during the filling process, making it easy for air bubbles to be generated inside the product. If the air in the cavity is not expelled in time during the filling process of high-temperature solid silicone rubber, it will lead to poor interfacial bonding in the product. Therefore, a uniform silicone rubber injection mold with a spiral flow channel is proposed to solve the above problems. Utility Model Content
[0005] To overcome the above deficiencies, this utility model provides a uniform silicone rubber injection mold with a spiral flow channel, which aims to improve the problems of uneven material filling and untimely venting in the prior art, which lead to bubbles and poor interfacial bonding in the product.
[0006] To achieve the above objectives, the present invention adopts the following technical solution:
[0007] A uniform silicone rubber injection mold with a spiral flow channel includes a fixed mold, a movable mold mounted on the top of the fixed mold, a positioning assembly between the fixed mold and the movable mold, a mold cavity on the side of the fixed mold near the movable mold, an air suction hole on the side of the movable mold near the fixed mold, a flow hole at the bottom of the movable mold, a vacuum pump on the outside of the movable mold, an exhaust hole on the side of the movable mold near the vacuum pump, a vacuum tube fixedly connected to the input end of the vacuum pump, a solenoid valve installed on the outside of the vacuum tube, a controller fixedly connected to the side of the vacuum pump away from the movable mold, a pressure sensor fixedly connected to the top of the movable mold, auxiliary components inside the movable mold, and a gate fixedly installed on the top of the movable mold.
[0008] As a further description of the above technical solution:
[0009] The auxiliary component includes a main flow channel, which is located inside the moving mold, and a threaded flow channel is provided on the side of the main flow channel near the fixed mold.
[0010] As a further description of the above technical solution:
[0011] The positioning component includes a positioning rod, which is fixedly connected to the side of the moving mold near the fixed mold. The fixed mold has a positioning hole on the side near the moving mold, and the positioning rod engages with the positioning hole.
[0012] As a further description of the above technical solution:
[0013] The fixed mold and the moving mold are connected by the positioning component.
[0014] As a further description of the above technical solution:
[0015] The moving mold is connected to the vacuum tube through the exhaust port, and the pressure sensor is installed inside the exhaust port.
[0016] As a further description of the above technical solution:
[0017] The vacuum pump, the solenoid valve, and the pressure sensor are all electrically connected to the controller.
[0018] As a further description of the above technical solution:
[0019] The flow hole is located directly above the mold cavity.
[0020] As a further description of the above technical solution:
[0021] The threaded flow channel is located inside the flow hole.
[0022] This utility model has the following beneficial effects:
[0023] 1. In this utility model, the vacuum pump is started by the controller. The vacuum pump quickly extracts the air in the mold cavity through the vacuum tube and the exhaust port. The suction port assists in the exhaust. The pressure sensor monitors the air pressure in the exhaust port in real time and feeds back the data so that the controller can accurately control the working status of the vacuum pump and the solenoid valve, improve the exhaust efficiency and effect, enhance the bonding strength between the high temperature solid silicone rubber and the mold cavity wall and between different melt flows, and improve the appearance quality and mechanical properties of the product.
[0024] 2. In this utility model, the molten high-temperature solid silicone rubber injected through the gate flows spirally along the threaded flow channel after the main runner, so that the melt flow rate is uniform and the mold cavity is filled more evenly. This effectively improves the problem of uneven melt flow rate and inconsistent filling sequence in traditional straight runners, reduces air bubbles caused by filling differences inside the product, and improves the overall density uniformity and quality stability of the product. Attached Figure Description
[0025] Figure 1 This is a three-dimensional schematic diagram of a uniform silicone rubber injection mold with a spiral flow channel proposed in this utility model.
[0026] Figure 2 This is a schematic diagram of the positioning component of a uniform silicone rubber injection mold with a spiral flow channel proposed in this utility model.
[0027] Figure 3 This is a schematic diagram of the auxiliary components of the uniform silicone rubber injection mold with a spiral flow channel proposed in this utility model.
[0028] Legend:
[0029] 1. Fixed mold; 2. Moving mold; 3. Mold cavity; 5. Positioning component; 6. Positioning rod; 7. Positioning hole; 8. Suction hole; 9. Exhaust hole; 10. Gate; 11. Runner; 12. Vacuum pump; 13. Vacuum tube; 14. Solenoid valve; 15. Controller; 16. Pressure sensor; 17. Auxiliary components; 18. Main runner; 19. Threaded runner. Detailed Implementation
[0030] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0031] Reference Figure 1 and Figure 2This utility model provides an embodiment of a uniform silicone rubber injection mold with a spiral flow channel, comprising a fixed mold 1, a movable mold 2 mounted on the top of the fixed mold 1, a positioning component 5 disposed between the fixed mold 1 and the movable mold 2, a mold cavity 3 formed on the side of the fixed mold 1 near the movable mold 2, an air suction hole 8 formed on the side of the movable mold 2 near the fixed mold 1, a flow hole 11 formed at the bottom of the movable mold 2, a vacuum pump 12 disposed on the outer side of the movable mold 2, an exhaust hole 9 formed on the side of the movable mold 2 near the vacuum pump 12, and a vacuum tube 13 fixedly connected to the input end of the vacuum pump 12. A solenoid valve 14 is installed on the outside of the vacuum tube 13. A controller 15 is fixedly connected to the side of the vacuum pump 12 away from the moving mold 2. A pressure sensor 16 is fixedly connected to the top of the moving mold 2. An auxiliary component 17 is provided inside the moving mold 2. A gate 10 is fixedly installed on the top of the moving mold 2. The fixed mold 1 and the moving mold 2 are connected by a positioning component 5. The moving mold 2 is connected to the vacuum tube 13 through an exhaust port 9. The pressure sensor 16 is installed inside the exhaust port 9. The vacuum pump 12, the solenoid valve 14, and the pressure sensor 16 are all electrically connected to the controller 15.
[0032] Specifically, the controller 15 uses a built-in control algorithm to compare the real-time air pressure data from the exhaust port 9 fed back by the pressure sensor 16 with a preset ideal air pressure threshold. This allows the controller 15 to respond according to the air pressure level. When the air pressure is higher than the upper limit, the controller increases the frequency or voltage amplitude of the electrical signal output to the vacuum pump 12 to increase its operating power. At the same time, it instructs the solenoid valve 14 to increase its opening, thereby accelerating the air discharge speed in the mold cavity 3. If the air pressure is lower than the lower limit, the controller reduces the frequency or voltage amplitude of the electrical signal output to the vacuum pump 12 to reduce its operating power and controls the solenoid valve 14 to decrease its opening, thereby stabilizing the exhaust process. In this way, the air pressure in the mold cavity 3 is maintained within the ideal range, thus efficiently expelling air and avoiding problems such as air bubbles and poor interfacial bonding caused by residual air in the product. This helps to improve the appearance quality and mechanical properties of the product.
[0033] Reference Figure 1 and Figure 3 The auxiliary component 17 includes a main runner 18, which is located inside the moving mold 2. A threaded flow channel 19 is provided on the side of the main runner 18 near the fixed mold 1. A flow hole 11 is located directly above the mold cavity 3, and the threaded flow channel 19 is located inside the flow hole 11.
[0034] Specifically, the silicone rubber raw material is heated to a molten state using an injection molding machine and efficiently injected into the mold through the gate 10. During this process, the melt first enters the main runner 18, and then flows in a spiral shape along the threaded runner 19. Due to the spiral structure design of the threaded runner 19, the velocity difference between different positions of the melt is effectively reduced during the flow. During the spiral flow, the melt is subjected to uniform shearing action from the sidewall of the threaded runner 19, which promotes more coordinated molecular movement inside the melt, thereby making the melt velocity more uniform. This uniform velocity distribution allows the melt to fill the mold cavity 3 more evenly, thus avoiding defects such as bubbles and weld lines caused by uneven filling in the mold cavity 3 due to uneven melt velocity. This helps to improve the internal structural uniformity and appearance quality of the product, while also enhancing the mechanical properties of the product.
[0035] Reference Figure 1 The positioning component 5 includes a positioning rod 6, which is fixedly connected to the side of the moving mold 2 near the fixed mold 1. The fixed mold 1 has a positioning hole 7 on the side near the moving mold 2, and the positioning rod 6 is engaged with the positioning hole 7.
[0036] Specifically, by precisely aligning the positioning rod 6 with the positioning hole 7 on the fixed mold 1, and then firmly engaging the positioning rod 6 into the positioning hole 7, the fixed mold 1 and the moving mold 2 can achieve precise docking. The high-precision fit between the positioning rod 6 and the positioning hole 7 effectively limits the possible displacement deviations of the fixed mold 1 and the moving mold 2 in various directions.
[0037] Working principle: Before the injection molding process begins, the fixed mold 1 and the moving mold 2 must be assembled. The positioning rod 6 is aligned with the positioning hole 7 on the fixed mold 1 and engaged to ensure precise docking between the fixed mold 1 and the moving mold 2. After the mold assembly is completed, the injection molding machine heats the silicone rubber raw material to a molten state and injects it into the mold through the gate 10. The melt first enters the main runner 18 and then flows in a spiral shape along the threaded runner 19. During this process, the melt flow rate tends to be uniform, thus filling the mold cavity 3 more evenly. At the same time, the controller 15 starts the vacuum pump 12. The vacuum pump 12 uses the vacuum tube 13 and the exhaust port 9 to extract the air from the mold cavity 3. The suction port 8 assists in the exhaust work. The pressure sensor 16 monitors the air pressure at the exhaust port 9 in real time and feeds the data back to the controller 15 to regulate the working status of the vacuum pump 12 and the solenoid valve 14.
[0038] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.
Claims
1. Uniform silicone injection mold with helical flow channel, comprising a fixed mold (1), characterized in that: The top of the fixed mold (1) is equipped with a movable mold (2), a positioning assembly (5) is arranged between the fixed mold (1) and the movable mold (2), a mold cavity (3) is arranged on the side of the fixed mold (1) close to the movable mold (2), an air suction hole (8) is arranged on the side of the movable mold (2) close to the fixed mold (1), a flow hole (11) is arranged at the bottom of the movable mold (2), a vacuum pump (12) is arranged on the outside of the movable mold (2), an exhaust hole (9) is arranged on the side of the movable mold (2) close to the vacuum pump (12), a vacuum pipe (13) is fixedly connected to the input end of the vacuum pump (12), an electromagnetic valve (14) is mounted on the outside of the vacuum pipe (13), a controller (15) is fixedly connected to the side of the vacuum pump (12) away from the movable mold (2), a pressure sensor (16) is fixedly connected to the top of the movable mold (2), an auxiliary assembly (17) is arranged in the movable mold (2), and a sprue (10) is fixedly mounted on the top of the movable mold (2).
2. The uniform silicone rubber injection mold having a spiral runner of claim 1, wherein: The auxiliary assembly (17) comprises a main flow channel (18), the main flow channel (18) is arranged in the movable mold (2), and a threaded flow channel (19) is arranged on the side of the main flow channel (18) close to the fixed mold (1).
3. The uniform silicone rubber injection mold having a spiral runner of claim 1, wherein: The positioning assembly (5) comprises a positioning rod (6), the positioning rod (6) is fixedly connected to the side of the movable mold (2) close to the fixed mold (1), a positioning hole (7) is arranged on the side of the fixed mold (1) close to the movable mold (2), and the positioning rod (6) is clamped with the positioning hole (7).
4. The uniform silicone rubber injection mold having a spiral runner of claim 1, wherein: The fixed mold (1) and the movable mold (2) are connected through the positioning assembly (5).
5. The uniform silicone rubber injection mold having a spiral flow channel of claim 1, wherein: The movable mold (2) is in communication with the vacuum pipe (13) through the exhaust hole (9), and the pressure sensor (16) is mounted in the exhaust hole (9).
6. The uniform silicone rubber injection mold having a spiral flow channel of claim 1, wherein: The vacuum pump (12), the electromagnetic valve (14) and the pressure sensor (16) are electrically connected with the controller (15).
7. The uniform silicone rubber injection mold having a spiral runner of claim 2, wherein: The flow hole (11) is arranged directly above the mold cavity (3).
8. The uniform silicone rubber injection mold having a spiral flow channel of claim 2, wherein: The threaded flow channel (19) is arranged in the flow hole (11).