Liquid silicone rubber injection device and its control method

Abstract

This invention provides a liquid silicone rubber injection device and its control method, belonging to the technical field of injection molding equipment design. The injection device includes a feeder, an injection molding machine, and a safety relief valve. The safety relief valve includes a valve body, within which a feed channel and a relief channel are formed. The feed channel connects the feeder and the injection molding machine and has a first flow port. A first one-way valve is provided within the feed channel to control the opening and closing of the first flow port. The relief channel is connected to the feed channel corresponding to the first side of the first flow port via a second flow port. A second one-way valve is provided within the relief channel to control the opening and closing of the second flow port. The second one-way valve's conduction direction is from the second flow port to the discharge port of the relief channel, and the opening pressure of the first one-way valve is lower than the opening pressure of the second one-way valve. This invention can prevent excessively pressurized liquid silicone rubber from causing frequent impacts on the barrel and screw.

Description

Technical Field

[0001] This invention belongs to the field of injection molding equipment design technology, specifically relating to a liquid silicone rubber injection device and its control method. Background Technology

[0002] Liquid Silicone Rubber (LSR) injection equipment mainly consists of an LSR feeder, an LSR injection molding machine, an LSR mold, and other related auxiliary equipment. The feeder uses a special mechanism to transport liquid materials of two components, A and B, to the mixer. These two materials are fully mixed in the mixer to form the required two-component liquid silicone rubber (LSR). The generated LSR is then transported to the barrel of the injection molding machine through pipelines, ready for injection.

[0003] Currently, most equipment on the market uses the method described above for injection molding of liquid silicone rubber. The liquid silicone rubber produced by mixing liquid components A and B is directly fed into the injection molding machine barrel without a safety relief valve or control system. This leads to the following problems:

[0004] (1) If the output pressure of the feeder is too high, it will impact the barrel and screw;

[0005] (2) If the pressure inside the mold cavity is too high, the liquid silicone rubber will flow back, and the pressure impact of the backflow will cause the feeding system to become unstable.

[0006] (3) After the liquid silicone rubber leaves the mixer, it is very easy for a small amount of solidification to occur in the delivery pipeline, barrel or mold, which reduces the injection fluidity. In order to ensure sufficient injection volume and injection speed, the injection system has to increase the injection pressure. Excessive injection pressure will affect the service life of the screw seal ring, resulting in material leakage from the seal ring and defects such as flash in the product. The solidified liquid silicone rubber will affect the normal operation of the screw check valve, thus affecting the dimensional accuracy of the product. The solidified material itself entering the mold cavity will also directly affect the quality of the product (uneven curing, insufficient glue, etc.). Summary of the Invention

[0007] Therefore, the technical problem to be solved by the present invention is to provide a liquid silicone rubber injection device and its control method, which can overcome the technical problems in the prior art, such as the lack of a safety pressure relief structure in the pipeline between the feeder and the injection machine, the excessive output pressure of the feeder causing the injection machine barrel and screw to be subjected to frequent impacts and reduce service life, and the excessive pressure in the downstream mold cavity causing the liquid silicone rubber to flow back and causing instability in the feeding system.

[0008] To address the aforementioned problems, this invention provides a liquid silicone rubber injection device, comprising a feeder, an injection molding machine, and a safety pressure relief valve. The safety pressure relief valve includes a valve housing, within which a feed channel and a pressure relief channel are formed. A first port of the feed channel is connected to the discharge port of the feeder, and a second port of the feed channel is connected to the inlet port on the barrel of the injection molding machine. The feed channel has a first flow port. A first one-way valve is provided within the feed channel and is located on a first side of the first flow port, controlling the opening and closing of the first flow port. The pressure relief channel is connected to the feed channel corresponding to the first side of the first flow port via a second flow port. A second one-way valve is provided within the pressure relief channel to control the opening and closing of the second flow port. The first one-way valve is directed from the first port to the second port, and the second one-way valve is directed from the second flow port to the discharge port of the pressure relief channel. The opening pressure of the first one-way valve is lower than the opening pressure of the second one-way valve.

[0009] In some embodiments, the valve housing is provided with a cooling channel surrounding the feeding channel, and the cooling channel is controllably connected by an external cooling fluid device; and / or, the valve housing is further provided with a pressure fluid inlet communicating with the pressure relief channel, the pressure fluid inlet being controllably connected to an external pressure fluid source.

[0010] In some embodiments, the pressure fluid inlet and the discharge port are respectively located on opposite sides of the pressure relief channel.

[0011] In some embodiments, the first one-way valve includes a first valve core, a first elastic element, and a first adjusting device, wherein the first elastic element is capable of applying force to the first valve core to cut off the flow of the first flow port, and the first adjusting device is capable of adjusting the elastic preload of the first elastic element; and / or, the second one-way valve includes a second valve core, a second elastic element, and a second adjusting device, wherein the second elastic element is capable of applying force to the second valve core to cut off the flow of the second flow port, and the second adjusting device is capable of adjusting the elastic preload of the second elastic element.

[0012] In some embodiments, the first valve core includes a first sealing core and a first slide rod integrally connected thereto; the first adjusting device includes a first worm gear, a first turbine gear paired with the first worm gear, and a first adjusting sleeve threadedly connected to the first turbine gear; the first adjusting sleeve is fitted onto the outside of the first slide rod and slidably connected thereto; the first elastic element is fitted onto the outside of the first slide rod and clamped between the end faces of the first sealing core and the first adjusting sleeve; and / or, the second valve core includes a second sealing core and a second slide rod integrally connected thereto; the second adjusting device includes a second worm gear, a second turbine gear paired with the second worm gear, and a second adjusting sleeve threadedly connected to the second turbine gear; the second adjusting sleeve is fitted onto the outside of the second slide rod and slidably connected thereto; the second elastic element is fitted onto the outside of the second slide rod and clamped between the end faces of the second sealing core and the second adjusting sleeve.

[0013] In some embodiments, the first turbine has flow holes extending through its two end faces; and / or, the first turbine is axially limited by a first retaining ring, and the second turbine is axially limited by a second retaining ring.

[0014] In some embodiments, the valve housing is provided with a pressure sensor capable of detecting the material pressure in the feeding channel corresponding to the first side; and / or, the valve housing is further provided with a proximity sensor capable of detecting the second slide bar to determine the on / off state of the second flow port.

[0015] In some embodiments, the second turbine separates the pressure relief passage into a sealed space, within which the free end of the second slide and the sensing element of the proximity sensor are located.

[0016] The present invention also provides a control method for the liquid silicone rubber injection device as described above, comprising the following steps:

[0017] Obtain the real-time pressure value of the material in the feeding channel corresponding to the first side;

[0018] Determine whether the real-time pressure value is higher than the opening pressure of the second one-way valve. When the real-time pressure value is higher than the opening pressure of the second one-way valve, obtain the on / off state of the second flow port. When the second flow port is in the cut-off state, control the operation of the second regulating device to reduce the opening pressure of the second one-way valve, thereby switching the second flow port to the connected state.

[0019] In some embodiments, when a pressure fluid inlet is formed on the valve body, after the second flow port switches to the connected state and then switches to the cut-off state again, an external pressure fluid source is controlled to connect with the pressure fluid inlet; and / or, when the real-time pressure value is higher than the opening pressure of the second check valve and the second flow port is in the cut-off state, an alarm message is issued to prompt the operator to inspect the second check valve.

[0020] This invention provides a liquid silicone rubber injection device and its control method. By installing a safety pressure relief valve on the pipeline between the feeder and the injection molding machine, when the pressure of the liquid silicone rubber output from the feeder is too high, the pressure inside the mold cavity is too high, causing the liquid silicone rubber to backflow, or the liquid silicone rubber to partially solidify and reduce its injection fluidity, resulting in the pressure of the liquid silicone rubber in the feed channel corresponding to the first side of the first flow port being higher than the opening pressure of the second one-way valve, the liquid silicone rubber will be unloaded and discharged in time through the second flow port. This prevents the excessive pressure of the liquid silicone rubber from causing frequent impacts on the barrel and screw, extending their service life, ensuring the stable operation of the feed system, preventing a reduction in the service life of the screw seal ring, and eliminating the problem of solidified small particles of silicone rubber causing the check valve to fail to close properly or blocking the mold flow channel, affecting the stability of the product (e.g., causing flash, insufficient glue, insufficient material, etc.). Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of the liquid silicone rubber injection device according to an embodiment of the present invention. In the figure, A represents the first material component and B represents the second material component.

[0022] Figure 2 yes Figure 1 A schematic diagram of the internal structure of the safety relief valve in the diagram.

[0023] The reference numerals in the attached figures are as follows:

[0024] 1. Feeder; 11. Mixer; 2. Injection molding machine; 21. Barrel; 22. Nozzle; 23. Check valve; 24. Screw; 25. Screw seal ring; 3. Safety relief valve; 31. Valve body; 311. First port; 312. Second port; 313. First flow port; 314. Second flow port; 315. Discharge port; 316. Cooling channel; 317. Pressure fluid inlet; 411. First sealing core; 412. ... 42. First elastic element; 431. First worm gear; 432. First turbine; 4321. Flow hole; 433. First adjusting sleeve; 511. Second sealing core; 512. Second slide rod; 52. Second elastic element; 531. Second worm gear; 532. Second turbine; 533. Second adjusting sleeve; 61. First retaining ring; 62. Second retaining ring; 71. Pressure sensor; 72. Proximity sensor; 100. Sealed space. Detailed Implementation

[0025] See also Figures 1 to 2 As shown in the embodiment of the present invention, a liquid silicone rubber injection device is provided, including a feeder 1, an injection molding machine 2, and a safety pressure relief valve 3. The safety pressure relief valve 3 includes a valve housing 31, in which a feeding channel (not labeled) and a pressure relief channel (not labeled) are formed. The first port 311 of the feeding channel is connected to the outlet (not labeled) of the feeder 1, and the second port 312 of the feeding channel is connected to the inlet (not labeled) on the barrel 21 of the injection molding machine 2. The feeding channel has a first flow port 313, and a first one-way valve is provided in the feeding channel, with the first one-way valve (not labeled) located on the first side of the first flow port 313 (i.e.,...). Figure 2 The indicated orientation is for reference, i.e., the lower side of the first flow port 313) and is used to control the opening and closing of the first flow port 313. The pressure relief channel is connected to the feeding channel corresponding to the first side of the first flow port 313 via the second flow port 314. The pressure relief channel is provided with a second one-way valve (not labeled in the figure) to control the opening and closing of the second flow port 314. The conduction direction of the first one-way valve is from the first port 311 to the second port 312 (with...). Figure 2 The orientation shown is for reference, i.e., from top to bottom. The conduction direction of the second one-way valve is from the second flow port 314 to the discharge port 315 of the pressure relief channel (with reference to...). Figure 2 The orientation shown is for reference (i.e., from left to right), and the opening pressure of the first check valve is lower than the opening pressure of the second check valve.

[0026] In this technical solution, a safety pressure relief valve 3 is installed on the pipeline between the feeder 1 and the injection molding machine 2. When the pressure of the liquid silicone rubber output by the feeder 1 is too high, the pressure inside the mold cavity is too high, the liquid silicone rubber flows back, or the liquid silicone rubber partially solidifies, causing a decrease in injection fluidity, resulting in the pressure of the liquid silicone rubber in the feed channel corresponding to the first side of the first flow port 313 being higher than the opening pressure of the second one-way valve, the liquid silicone rubber will be unloaded and discharged in time through the second flow port 314. This prevents the excessive pressure of the liquid silicone rubber from causing frequent impacts on the barrel and screw, extending their service life, ensuring the stable operation of the feed system, preventing a reduction in the service life of the screw sealing ring 25, and preventing solidified small particles of silicone rubber from causing the check valve 23 to fail to close properly or block the mold flow channel, affecting the stability of the product (e.g., causing flash, insufficient glue, insufficient material, etc.).

[0027] In some embodiments, the valve housing 31 is provided with a cooling channel 316, which surrounds the feeding channel. The cooling channel 316 is connected in a controllable manner by an external cooling fluid device. The aforementioned external cooling fluid device can be, for example, an existing water chiller unit. In principle, any cooling source component that can provide cooling fluid (cooling water, cooling airflow) can be selected.

[0028] In this technical solution, by setting a cooling channel 316 around the feeding channel inside the valve housing 31, the cooling medium flowing in the cooling channel 316 can control the temperature of the liquid silicone rubber fluid in the feeding channel, preventing the liquid silicone rubber from forming high-speed friction with the components inside the valve housing 31 during the feeding injection molding process, which would cause local overheating and thermal curing, thereby improving product stability.

[0029] In some embodiments, the valve housing 31 is further provided with a pressure fluid inlet 317 that communicates with the pressure relief channel. The pressure fluid inlet 317 is used to controllably communicate with an external pressure fluid source. The aforementioned pressure fluid source may be, for example, a high-pressure air pipeline system at the work site, or a separately configured air compressor or a high-pressure water pump. In principle, any device that can provide a high-pressure fluid can be selected.

[0030] In this technical solution, by setting a pressure fluid inlet 317 on the valve body 31, the pressure fluid can be used to clean the pressure relief channel, so as to minimize the possibility that the liquid silicone rubber discharged from the feeding channel will remain in the pressure relief channel and solidify, causing channel blockage or hindering the opening and closing of the second one-way valve.

[0031] In some embodiments, the pressure fluid inlet 317 and the discharge port 315 are respectively located on opposite sides of the pressure relief channel. This enables the pressure fluid to efficiently clean the residual liquid silicone rubber in the pressure relief channel, minimizing or even eliminating the residue of liquid silicone rubber.

[0032] In some embodiments, the first one-way valve includes a first valve core (not labeled in the figure), a first elastic element 42, and a first adjusting device (not labeled in the figure). The first elastic element 42 is capable of applying force to the first valve core to cut off the flow of the first flow port 313. The first adjusting device is capable of adjusting the elastic preload (i.e., elastic compression force) of the first elastic element 42. The aforementioned first elastic element 42 can be, for example, a helical spring that does not cause physical or chemical contamination to the liquid silicone rubber. Similarly, the second one-way valve includes a second valve core (not labeled in the figure), a second elastic element 52, and a second adjusting device (not labeled in the figure). The second elastic element 52 is capable of applying force to the second valve core to cut off the flow of the second flow port 314. The second adjusting device is capable of adjusting the elastic preload of the second elastic element 52.

[0033] In this technical solution, a first adjustment device and a second adjustment device are respectively provided for the first one-way valve and the second one-way valve to adjust the elastic preload of the first elastic element 42 and the second elastic element 52 respectively. In this way, the first one-way valve and the second one-way valve can be adjusted in a timely manner during the use of the safety relief valve 3, ensuring that the opening pressure of the two one-way valves can be at the preset value. This prevents the valve opening pressure from decreasing due to the loosening of the elastic element after long-term use or the valve opening pressure from the solidification of residual liquid silicone rubber, which would affect the stability of the product.

[0034] In some implementation methods, see details. Figure 2As shown, the first valve core includes a first sealing core 411 and a first slide rod 412 integrally connected thereto (either assembled or integrally formed). The first adjusting device includes a first worm gear 431, a first turbine gear 432 mating with the first worm gear 431, and a first adjusting sleeve 433 threadedly connected to the first turbine gear 432. The first adjusting sleeve 433 is fitted onto the outside of the first slide rod 412 and the two are slidably connected. The first elastic element 42 is fitted onto the outside of the first slide rod 412 and is clamped between the end faces of the first sealing core 411 and the first adjusting sleeve 433. And / or, the second valve core includes a second sealing core 511 and a second slide rod 512 integrally connected thereto (either assembled or integrally formed). The second adjustment device includes a second worm 531, a second turbine 532 paired with the second worm 531, and a second adjustment sleeve 533 threadedly connected to the second turbine 532. The second adjustment sleeve 533 is fitted onto the outside of the second slide rod 512 and the two are slidably connected. The second elastic element 52 is fitted onto the outside of the second slide rod 512 and is clamped between the end faces of the second sealing core 511 and the second adjustment sleeve 533. It is understood that the aforementioned first worm 431 and second worm 531 are respectively equipped with drive motors (not shown in the figure) capable of driving their respective rotation. Thus, when it is necessary to adjust the elastic preload of the first elastic element 42 or the second elastic element 52, the corresponding drive motor can be controlled to rotate forward or backward by a certain angle. Specifically, with Figure 2The indicated orientation is for reference. When it is necessary to increase the opening pressure of the first one-way valve, the first worm gear 431 is controlled to rotate forward (assumed). At this time, it drives the first turbine 432 to rotate forward (assumed). Since the first turbine 432 is threadedly connected to the first adjusting sleeve 433, the rotational motion of the first turbine 432 is converted into the linear displacement of the first adjusting sleeve 433, and it moves upward to compress the first elastic element 42, thereby increasing the elastic preload of the first elastic element 42, that is, increasing the opening pressure of the first one-way valve. Conversely, when it is necessary to reduce the opening pressure of the first one-way valve... When the opening pressure of the first check valve is reached, the first worm gear 431 is controlled to rotate in the reverse direction. This drives the first turbine 432 to rotate in the reverse direction. Since the first turbine 432 is threadedly connected to the first adjusting sleeve 433, the rotational motion of the first turbine 432 is converted into a linear displacement of the first adjusting sleeve 433, which moves downwards away from the first elastic element 42. This reduces the elastic preload of the first elastic element 42, thus reducing the opening pressure of the first check valve. The adjustment of the opening pressure of the second check valve is similar to that of the first check valve and will not be described in detail. The cross-sections of the first slide rod 412 and the second slide rod 512 are preferably non-circular, such as elliptical or quadrilateral shapes with anti-misalignment features, to prevent the first adjusting sleeve 433 or the second adjusting sleeve 533 from rotating relative to the first slide rod 412 or the second slide rod 512, making the opening and closing movement of the valve core more precise.

[0035] In this technical solution, a worm gear turbine combined with a threaded connection between the turbine and the adjusting sleeve is used to convert rotary motion into linear motion to adjust the elastic preload of the elastic element. At the same time, the self-locking effect of the threaded connection can be used to reliably lock the opening pressure of the one-way valve.

[0036] In some embodiments, the first turbine 432 has flow holes 4321 extending through its two end faces, which can ensure the flow area of ​​the liquid silicone rubber and ensure the structural compactness of the safety relief valve 3.

[0037] The first turbine 432 is axially limited by the first retaining ring 61, and the second turbine 532 is axially limited by the second retaining ring 62. It is understood that the side of the first turbine 432 and the second turbine 532 away from the corresponding retaining ring forms an axial limit with the internal shoulder of the valve housing 31. The aforementioned internal shoulder and the position where the retaining ring abuts against the turbine should ensure a low roughness to ensure smooth rotation of the turbine.

[0038] In some embodiments, the valve housing 31 is provided with a pressure sensor 71 capable of detecting the material pressure in the feeding channel corresponding to the first side. This allows the operator to adjust the opening pressure of the first one-way valve based on the detection value of the pressure sensor 71, or to determine whether to control the second one-way valve to force unload based on the detection value of the pressure sensor 71 and the on / off state of the second one-way valve, thus preventing adverse phenomena caused by the failure of the second one-way valve to unload.

[0039] The valve housing 31 is also provided with a proximity sensor 72 that can detect the second slide bar 512 to determine the on / off state of the second flow port 314. That is, the position of the second slide bar 512 can be detected in real time by the proximity sensor 72. When the proximity sensor 72 senses the second slide bar 512, it means that the second flow port 314 has been opened (i.e., in a connected state). Otherwise, the second flow port 314 is in a cut-off state.

[0040] See details Figure 2 As shown, in some embodiments, the second turbine 532 separates the pressure relief channel into a sealed space 100, and the free end of the second slide bar 512 and the sensing element of the proximity sensor 72 are located within the sealed space 100 to prevent the liquid silicone rubber residue discharged during unloading from solidifying in the sensing areas of the proximity sensor 72 and the second slide bar 512, which could lead to incorrect detection results.

[0041] According to an embodiment of the present invention, a control method for the liquid silicone rubber injection device as described above is also provided, comprising the following steps:

[0042] The system obtains the real-time pressure value of the material in the feeding channel corresponding to the first side. When the pressure of the liquid silicone rubber output by the feeder is too high, or when the pressure in the mold cavity is too high, causing the liquid silicone rubber to backflow, the real-time pressure value in the feeding channel corresponding to the first side will be higher than the opening pressure of the second one-way valve. At this time, the control system can obtain and feed back to the corresponding control system in a timely manner through the aforementioned pressure sensor 71 to determine whether the real-time pressure value is higher than the opening pressure of the second one-way valve. When the real-time pressure value is higher than the opening pressure of the second one-way valve, the system obtains the on / off state of the second flow port 314. Specifically, the system can obtain whether the second slide bar 512 is within its sensing range through the aforementioned proximity sensor 72. When the second slide bar 512 is within the sensing range of the proximity sensor 72, it indicates that the second slide bar 512 has shifted to the right (towards...). Figure 2(The indicated orientation is for reference only), meaning the second flow port 314 is in a connected state, i.e., the second one-way valve is in an open state, allowing for timely overflow and discharge of excessively pressurized liquid silicone rubber, preventing adverse effects caused by excessive pressure. When the second flow port 314 is in a cut-off state, i.e., the proximity sensor 72 does not detect the aforementioned second slide bar 512, it indicates that the second one-way valve is not open. In this case, the second regulating device should be operated promptly to reduce the opening pressure of the second one-way valve, thereby allowing the second flow port 314 to switch to a connected state as quickly as possible, and timely discharge of excessively pressurized liquid silicone rubber. This effectively prevents subsequent adverse phenomena caused by the inability to discharge excessively pressurized liquid silicone rubber in time due to obstruction of the second one-way valve's opening. Furthermore, as a preferred implementation, a corresponding warning message should also be issued. That is, when the real-time pressure value is higher than the opening pressure of the second one-way valve and the second flow port 314 is in a cut-off state, an alarm message should be issued to prompt the operator to inspect the second one-way valve.

[0043] In some embodiments, when a pressure fluid inlet 317 is formed on the valve housing 31, after the second flow port 314 switches to the connected state and then switches to the cut-off state again, the external pressure fluid source is controlled to connect with the pressure fluid inlet 317 so as to use the external pressure fluid to efficiently clean the valve of the pressure relief channel and prevent liquid silicone rubber from remaining in the pressure relief channel.

[0044] It will be readily understood by those skilled in the art that the aforementioned advantageous methods can be freely combined and superimposed without conflict.

[0045] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention. The above are merely preferred embodiments of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the protection scope of the present invention.

Claims

1. A liquid silicone rubber injection device, characterized in that, The system includes a feeder (1), an injection molding machine (2), and a safety relief valve (3). The safety relief valve (3) includes a valve housing (31), which has a feed channel and a pressure relief channel. The first port (311) of the feed channel is connected to the outlet of the feeder (1), and the second port (312) of the feed channel is connected to the inlet of the barrel (21) of the injection molding machine (2). The feed channel has a first flow port (313). The feed channel is equipped with a first one-way valve, which is located on the first side of the first flow port (313) and is used to control the opening and closing of the first flow port (313). The first side is the side of the first flow port (313) that is close to the inlet of the barrel (21). The pressure relief channel is connected to the feed channel corresponding to the first side of the first flow port (313) via a second flow port (314). The pressure relief channel is provided with a second one-way valve to control the opening and closing of the second flow port (314). The first one-way valve is directed from the first port (311) to the second port (312), and the second one-way valve is directed from the second flow port (314) to the discharge port (315) of the pressure relief channel. The opening pressure of the first one-way valve is lower than the opening pressure of the second one-way valve. The valve body (31) is also provided with a pressure fluid inlet (317) that communicates with the pressure relief channel. The pressure fluid inlet (317) is used to controllably communicate with an external pressure fluid source. The pressure fluid inlet (317) and the discharge port (315) are respectively located on opposite sides of the pressure relief channel. After the second flow port (314) is switched to the connected state and then switched to the cut-off state again, the external pressure fluid source is controlled to communicate with the pressure fluid inlet (317).

2. The liquid silicone rubber injection device according to claim 1, characterized in that, The valve housing (31) is provided with a cooling channel (316), which surrounds the feeding channel and is connected in a controllable manner by an external cooling fluid device.

3. The liquid silicone rubber injection device according to claim 1, characterized in that, The first one-way valve includes a first valve core, a first elastic element (42), and a first adjusting device, wherein the first elastic element (42) can apply force to the first valve core to cut off the flow of the first flow port (313), and the first adjusting device can adjust the elastic preload of the first elastic element (42); and / or, the second one-way valve includes a second valve core, a second elastic element (52), and a second adjusting device, wherein the second elastic element (52) can apply force to the second valve core to cut off the flow of the second flow port (314), and the second adjusting device can adjust the elastic preload of the second elastic element (52).

4. The liquid silicone rubber injection device according to claim 3, characterized in that, The first valve core includes a first sealing core (411) and a first slide rod (412) integrally connected thereto. The first adjusting device includes a first worm gear (431), a first turbine gear (432) mated with the first worm gear (431), and a first adjusting sleeve (433) threadedly connected to the first turbine gear (432). The first adjusting sleeve (433) is fitted onto the outside of the first slide rod (412) and the two are slidably connected. The first elastic element (42) is fitted onto the outside of the first slide rod (412) and is clamped between the end faces of the first sealing core (411) and the first adjusting sleeve (433). Alternatively, the second valve core includes a second sealing core (511) and a second slide rod (512) integrally connected thereto. The second adjusting device includes a second worm gear (531), a second turbine gear (532) paired with the second worm gear (531), and a second adjusting sleeve (533) threadedly connected to the second turbine gear (532). The second adjusting sleeve (533) is fitted on the outside of the second slide rod (512) and the two are slidably connected. The second elastic element (52) is fitted on the outside of the second slide rod (512) and is clamped between the end faces of the second sealing core (511) and the second adjusting sleeve (533).

5. The liquid silicone rubber injection device according to claim 4, characterized in that, The first turbine (432) has a flow passage (4321) extending through its two end faces; and / or, the first turbine (432) is axially limited by a first retaining ring (61), and the second turbine (532) is axially limited by a second retaining ring (62).

6. The liquid silicone rubber injection device according to claim 4, characterized in that, The valve housing (31) is provided with a pressure sensor (71) capable of detecting the material pressure in the feeding channel corresponding to the first side; and / or, the valve housing (31) is also provided with a proximity sensor (72) capable of detecting the second slide bar (512) to determine the on / off state of the second flow port (314).

7. The liquid silicone rubber injection device according to claim 6, characterized in that, The second turbine (532) separates the pressure relief passage into a sealed space (100), and the free end of the second slide bar (512) and the sensing element of the proximity sensor (72) are located in the sealed space (100).

8. A control method for a liquid silicone rubber injection device as described in any one of claims 3 to 7, characterized in that, Includes the following steps: Obtain the real-time pressure value of the material in the feeding channel corresponding to the first side; Determine whether the real-time pressure value is higher than the opening pressure of the second one-way valve. When the real-time pressure value is higher than the opening pressure of the second one-way valve, obtain the on / off state of the second flow port (314). When the second flow port (314) is in the cut-off state, control the operation of the second regulating device to reduce the opening pressure of the second one-way valve, thereby causing the second flow port (314) to switch to the connected state.

9. The control method according to claim 8, characterized in that, When the real-time pressure value is higher than the opening pressure of the second check valve and the second flow port (314) is in a cut-off state, an alarm message is issued to prompt the operator to inspect the second check valve.

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