Cold runner system for injection molding of liquid silica gel

Abstract

The invention relates to a cold runner system for liquid silica gel injection molding, which comprises a mold, a cold runner plate is arranged on the mold, a heat insulation plate covers the cold runner plate, a needle valve part is arranged at the cold runner plate in a penetrating manner, a circulating cooling liquid channel is arranged in the cold runner plate, and a heat insulation plate is arranged on the heat insulation plate. Two ends of the circulating cooling liquid channel are respectively connected with the water inlet and the water outlet. The cold runner system for liquid silica gel injection molding has the beneficial effects that the two water path pipes are arranged in the cold runner plate, the water path pipes are bent and spread in the cold runner plate, and the two ends of the two water path pipes are connected with the first water inlet, the first water path water outlet, the second water path water inlet and the second water path water outlet correspondingly; the first water inlet, the first water path water outlet and the water path pipe form a circulating water path, the second water path water inlet, the second water path water outlet and the water path pipe form a circulating water path used for cooling the cold runner plate through water circulation, and the cold runner plate is arranged on the end wall of the mold so as to cool the mold.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of heater device, in particular to a cold runner system for liquid silicone rubber injection molding. BACKGROUND

[0002] Liquid silicone rubber is widely used in high-end fields such as medical, food, baby products and automobile sealing due to its excellent biocompatibility, high and low temperature resistance, chemical inertness and soft touch. In the process of LSR injection molding, the runner system as a key component connecting the injection molding machine nozzle and the mold cavity directly determines the production efficiency, material utilization rate and product quality.

[0003] Currently, there are two main runner technology solutions on the market. The first is a hot runner system. This solution keeps the plastic in the runner in a molten state at all times through heating elements, thereby avoiding the generation of pouring waste. For most thermoplastic plastics, the effect is significant. However, LSR is a thermosetting material, and its curing process is an irreversible vulcanization crosslinking reaction. If a hot runner is used, the high temperature environment in the runner will cause the LSR to pre-cure, resulting in not only waste of raw materials and clogging of the runner, but also frequent cleaning and maintenance that can seriously disrupt production, leading to low efficiency and high cost. SUMMARY

[0004] The purpose of the present application is to provide a cold runner system for liquid silicone rubber injection molding to solve the problem that the existing LSR is a thermosetting material, and its curing process is an irreversible vulcanization crosslinking reaction. If a hot runner is used, the high temperature environment in the runner will cause the LSR to pre-cure, resulting in not only waste of raw materials and clogging of the runner, but also frequent cleaning and maintenance that can seriously disrupt production, leading to low efficiency and high cost.

[0005] To achieve the above purpose, the present application provides the following technical solution: a cold runner system for liquid silicone rubber injection molding, comprising a mold, a cold runner plate arranged on the mold, a heat insulation plate covered on the cold runner plate, a needle valve part penetrating the cold runner plate, a circulating cooling liquid channel arranged in the cold runner plate, and a water inlet and a water outlet connected to both ends of the circulating cooling liquid channel, respectively.

[0006] Preferably, a connecting port is formed in the side wall of the cold runner plate, and a water stop plug for sealing the connecting port is threadedly connected in the connecting port.

[0007] Preferably, the needle valve part includes a titanium alloy nozzle fastened by a screw at the end wall of the cold runner plate, a water jacket connected to the titanium alloy nozzle, and a needle valve system arranged in the water jacket.

[0008] Preferably, the water jacket penetrates the heat insulation plate, and the water jacket, the needle valve system and the titanium alloy nozzle are each provided with three.

[0009] Preferably, the connecting port is distributed around the three end faces of the cold runner plate.

[0010] Preferably, a shunt runner plate is clamped at the center of the bottom wall of the cold runner plate, and a shunt cavity is formed at the end wall of the shunt runner plate.

[0011] Preferably, the circulating cooling liquid channel is a pair of waterway pipes that are bent.

[0012] Preferably, the water inlet includes a first water inlet connected to one end of a waterway pipe and a second water inlet connected to one end of another waterway pipe.

[0013] Preferably, the water outlet includes a second water inlet connected to one end of a waterway pipe and a second water outlet connected to one end of another waterway pipe.

[0014] Compared with the prior art, the present application has the following advantages:

[0015] 1. The present application uses the rotation of the water stop plug to open and close the connecting port, and then controls the direction of the waterway through the waterway of the water stop plug.

[0016] 2. Two waterway pipes are arranged in the cold runner plate, the waterway pipes are bent and laid in the cold runner plate, and the two ends of the two waterway pipes are connected to the first water inlet, the first water outlet, the second water inlet, and the second water outlet, respectively. The first water inlet, the first water outlet, and the waterway pipe form a circulating waterway, and the second water inlet, the second water outlet, and the waterway pipe form a circulating waterway, which is used for water circulation cooling of the cold runner plate. The cold runner plate is arranged at the end wall of the mold, thereby cooling the mold.

[0017] 3. The water jacket, needle valve system, and titanium alloy nozzle form a conical valve needle structure. The valve needle is opened under the pressure of the gas valve and is closed instantly after the pressure is removed, completely eliminating the flow and dripping phenomenon of LSR. The heat insulation plate is covered on the cold runner plate to form a connection. The end of the nozzle adopts a conical valve needle structure of a low-temperature-resistant gas valve. The valve needle is opened under the pressure of the gas valve and is closed instantly after the pressure is removed, completely eliminating the flow and dripping phenomenon of LSR.

[0018] 4. The shunt runner plate is arranged at the end wall of the cold runner plate, and the shunt cavity is arranged at the shunt runner plate, which is used for cooperation cooling. In the whole structure, the cooling liquid channel adopts a ring-shaped structure to cover the main runner and the shunt runner, and cooperates with the heating rod to work. Through the PID controller, the working temperature of the runner is accurately stabilized in the critical range of 15℃-35℃, ensuring that the LSR is always in the lowest viscosity melting state without vulcanization reaction.

[0019] 5, through the water cooling machine temperature to 15 °, in through the water pump 2 kg pressure water transmission to the water inlet and water inlet, and then through a cycle to the water outlet and water outlet;

[0020] 6, water temperature once more than the set temperature, water cooling machine will work through the compressor water temperature to 15 °, water through the water inlet to the water jacket, to reduce the temperature of the needle valve system, mold heating plate through the heat insulation plate in the middle to reduce the heat transfer efficiency, nozzle and mold heating plate contact, material using titanium alloy to reduce the heat transfer efficiency, through the water to reduce the temperature of the heat insulation plate and nozzle, mold flow channel due to itself does not have temperature, through the water temperature transmission plate can effectively control the temperature 15 ℃-35 ℃. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 For the structure of the present application for liquid silicone injection molding cold runner system schematic diagram;

[0022] Figure 2 For the water jacket structure of the present application for liquid silicone injection molding cold runner system schematic diagram;

[0023] Figure 3 For the cold runner plate structure of the present application for liquid silicone injection molding cold runner system schematic diagram;

[0024] Figure 4 For the cold runner plate rear side structure of the present application for liquid silicone injection molding cold runner system schematic diagram;

[0025] Figure 5 For the cold runner plate structure of the present application for liquid silicone injection molding cold runner system schematic diagram;

[0026] Figure 6 For the water route pipe and the first water inlet structure of the present application for liquid silicone injection molding cold runner system schematic diagram.

[0027] In the figure: 1, mold; 2, cold runner plate; 3, heat insulation plate; 4, water jacket; 5, needle valve system; 6, titanium alloy nozzle; 7, flow channel plate; 8, flow cavity; 9, water route pipe; 10, first water inlet; 11, first water outlet; 12, second water inlet; 13, second water outlet; 14, connecting port; 15, water stop plug. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments.

[0029] In the description of the present application, unless otherwise specified, the meaning of "a plurality of" is two or more than two; the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", "third" and the like are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0030] In the description of the present application, it should be noted that, unless otherwise specified and limited, the terms "connected", "connected" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0031] Please refer to Figures 1-6 The present application provides a technical scheme: a cold runner system for liquid silicone rubber injection molding, comprising a mold 1, a cold runner plate 2 is arranged on the mold 1, a heat insulation plate 3 is covered on the cold runner plate 2, a needle valve part is provided at the cold runner plate 2, a circulating cooling liquid channel is arranged in the cold runner plate 2, and the two ends of the circulating cooling liquid channel are respectively connected with a water inlet and a water outlet;

[0032] A connecting port 14 is formed in the side wall of the cold runner plate 2, and a water stop plug 15 for sealing the connecting port 14 is threadedly connected in the connecting port 14;

[0033] The needle valve part comprises a titanium alloy nozzle 6 fixedly connected by screws at the end wall of the cold runner plate 2, a water jacket 4 connected on the titanium alloy nozzle 6, and a needle valve system 5 arranged inside the water jacket 4, the water jacket 4 penetrates the heat insulation plate 3 and is distributed, the water jacket 4, the needle valve system 5 and the titanium alloy nozzle 6 are all provided with three, and the connecting port 14 is distributed around the three end faces of the cold runner plate 2;

[0034] A shunt runner plate 7 is clamped at the center of the bottom wall of the cold runner plate 2, a shunt cavity 8 is formed at the end wall of the shunt runner plate 7, and the circulating cooling liquid channel is a pair of waterway pipes 9 which are bent;

[0035] The water inlet comprises a first water inlet 10 connected at one end of one waterway pipe 9 and a second water inlet 12 connected at one end of another waterway pipe 9, and the water outlet comprises a second water inlet 12 connected at one end of one waterway pipe 9 and a second water outlet 13 connected at one end of another waterway pipe 9.

[0036] In summary, the cold runner system for liquid silicone rubber injection molding is used,

[0037] The water stop plug 15 is rotated to open and close the connecting port 14, and then the water path direction is controlled through the water path of the water stop plug 15.

[0038] Two water path pipes 9 are arranged in the cold runner plate 2, the water path pipes 9 are bent in the cold runner plate 2, two ends of the two water path pipes 9 are connected with the first water inlet 10, the first water outlet 11, the second water inlet 12 and the second water outlet 13 respectively, the first water inlet 10, the first water outlet 11 and the water path pipe 9 constitute a circulating water path, the second water inlet 12, the second water outlet 13 and the water path pipe 9 constitute a circulating water path, which is used for water circulation cooling of the cold runner plate 2, the cold runner plate 2 is arranged at the end wall of the mold 1, and then the mold 1 is cooled.

[0039] The water jacket 4, the needle valve system 5 and the titanium alloy nozzle 6 constitute a conical valve needle structure, the valve needle is opened under the pressure of the air valve, and is closed instantly after the pressure is removed, so that the LSR flow and dripping phenomenon is completely eliminated.

[0040] The heat insulation plate 3 is covered on the cold runner plate 2 to form a connection.

[0041] The shunt plate 7 is arranged at the end wall of the cold runner plate 2, the shunt cavity 8 is arranged at the shunt plate 7, which is used for cooperating cooling, in the whole structure, the cooling liquid channel adopts a ring type structure to cover the main flow channel and the shunt channel, and cooperates with the heating rod to work, through the PID controller, the flow channel working temperature is accurately stabilized in the critical range of 15℃-35℃, so that the LSR is always in the lowest viscosity melting state without vulcanization reaction.

[0042] The above is only the preferred specific embodiment of the present application, but the protection scope of the present application is not limited to this, any skilled person in the art can make equivalent replacement or change according to the technical scheme and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered in the protection scope of the present application.

Claims

1. A cold runner system for injection molding of liquid silicone, comprising a mold (1), characterized in that: The mold (1) is provided with a cold runner plate (2), and a heat insulation plate (3) is covered on the cold runner plate (2). A needle valve is provided in the cold runner plate (2), and a circulating coolant channel is arranged inside the cold runner plate (2). The two ends of the circulating coolant channel are respectively connected to the inlet and the outlet.

2. The cold runner system for liquid silicone injection molding according to claim 1, characterized in that: The cold runner plate (2) has a connection port (14) on its side wall, and a water stop plug (15) for sealing the connection port (14) is threaded inside the connection port (14).

3. A cold runner system for injection molding of liquid silicone according to claim 2, characterized in that: The needle valve section includes a titanium alloy nozzle (6) fastened to the end wall of the cold runner plate (2) by screws, a water jacket (4) connected to the titanium alloy nozzle (6), and a needle valve system (5) arranged inside the water jacket (4).

4. A cold runner system for injection molding of liquid silicone according to claim 3, characterized in that: The water jacket (4) is distributed through the heat insulation plate (3), and three of each of the water jacket (4), needle valve system (5) and titanium alloy nozzle (6) are provided.

5. A cold runner system for injection molding of liquid silicone according to claim 4, characterized in that: The connection port (14) is distributed around the three end faces of the cold runner plate (2).

6. A cold runner system for injection molding of liquid silicone according to claim 5, characterized in that: A flow divider plate (7) is snapped into the center of the bottom wall of the cold flow channel plate (2), and a flow divider cavity (8) is opened at the end wall of the flow divider plate (7).

7. A cold runner system for injection molding of liquid silicone according to claim 6, characterized in that: The circulating coolant passage is a pair of bent water pipes (9).

8. A cold runner system for injection molding of liquid silicone according to claim 7, characterized in that: The water inlet includes a first water inlet (10) connected to one end of a water pipe (9) and a second water inlet (12) connected to one end of another water pipe (9).

9. A cold runner system for injection molding of liquid silicone according to claim 8, characterized in that: The outlet includes a second water inlet (12) connected to one end of a water pipe (9) and a second water outlet (13) connected to one end of another water pipe (9).

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