A resin casting body preparation device and its preparation method

Abstract

The present invention relates to the technical field of resin matrix composite material forming, and particularly relates to a resin casting body preparation device and a preparation method thereof. The device includes a mold, a pressure diaphragm, a pneumatic pipeline, a gas source device, an electro-pneumatic proportional valve and a controller. The mold has a forming cavity and a side mold pressure cavity, and the mold has a resin injection pipeline interface hole for injecting resin into the forming cavity from the resin injection pipeline interface hole; the pressure diaphragm is used to isolate the forming cavity and the side mold pressure cavity and deform under a certain pressure; the pneumatic pipeline guides gas to flow into or out of the side mold pressure cavity; the gas source device is connected to the pneumatic pipeline and is used to input gas into the pneumatic pipeline; the electro-pneumatic proportional valve is arranged on the pneumatic pipeline and is used to control the pressure of the side mold pressure cavity according to an electrical signal; the controller controls the opening degree of the electro-pneumatic proportional valve in the pneumatic pipeline; the purpose is to solve the safety problems in the current resin casting body preparation process and reduce the internal pores of the prepared resin casting body.

Description

Technical Field

[0001] The invention relates to the technical field of resin-based composite material molding, and in particular to a resin casting body preparation device and a preparation method thereof. Background Art

[0002] The main principle of resin transfer molding (RTM) technology is to first lay a designed preform in a mold cavity, then inject a special resin system into the mold cavity using an injection device, discharge the gas in the mold cavity through the flow of resin and simultaneously infiltrate the fiber, and then heat, solidify, and cool to demould to obtain a composite material product. In the process of preparing a resin casting, if there is no pressure in the resin during the curing and shrinking stage, pores are easily generated. In addition, when the reaction heat accumulated by a large amount of resin during the heating and curing process cannot be discharged in time, it will cause resin explosion. The resin casting preparation process needs to control the resin reaction rate in the reactor to avoid explosion. When explosion occurs, the preparation device must be able to effectively protect the safety of personnel and equipment. Therefore, the inventor provides a resin casting preparation device and a preparation method thereof. Summary of the invention

[0003] The present invention mainly aims at the above problems and proposes a resin casting preparation device and a preparation method thereof, the purpose of which is to solve the safety problem in the current resin casting preparation process and reduce the internal pores of the prepared resin casting.

[0004] To achieve the above object, the present invention provides a device for preparing a resin casting, the device comprising:

[0005] A mold having a molding cavity for molding a product and a side mold pressure cavity for regulating the molding cavity pressure, and the mold also has a resin injection pipeline interface hole connected to the molding cavity, so as to inject resin into the molding cavity from the resin injection pipeline interface hole;

[0006] A pressure diaphragm, used to isolate the molding cavity and the side mold pressure cavity and deform under a certain pressure;

[0007] A gas pressure pipeline, directing gas to flow into or out of the side mold pressure cavity;

[0008] A gas source device, which is in communication with the air pressure pipeline and is used to input gas into the air pressure pipeline;

[0009] an electrical proportional valve, which is arranged on the air pressure pipeline and is used to control the pressure of the side mold pressure chamber according to an electrical signal; and

[0010] A controller controls the opening of the electrical proportional valve in the air pressure pipeline.

[0011] Further, the pressure diaphragm is used to isolate the molding cavity and the side mold pressure cavity and rupture after reaching the deformation limit under a certain pressure.

[0012] Further, the pressure diaphragm is made of silicone rubber.

[0013] Further, the mold has a plurality of cooling inlets for guiding cooling fluid or cooling gas to flow to each individual cooling channel partition; each of the cooling inlets is connected to a cooler through a separate pipeline, and a cooling pipeline cut-off valve is provided on the pipeline connecting the cooling inlet and the cooler separately. The cooling pipeline cut-off valve is controlled by the controller, and under the control of the controller, the pipeline is selectively conducted to cool the cooling channel partition separately.

[0014] Further, the device further includes a plurality of thermocouples, which are connected to the controller and used to sense the temperature of each cooling channel partition and send an electrical signal for sensing the temperature of each cooling channel partition to the controller.

[0015] Further, the mold has a plurality of cooling return ports for guiding the cooling fluid or cooling gas to flow back from the cooling channel partition to the cooler.

[0016] Further, a plurality of cooling channels respectively communicating with the cooling inlets and the cooling return ports are arranged in the mold. The cooling channels are at least one of a "C" - shaped structure, a spiral structure or a meandering structure that are not connected end - to - end. A temperature measuring hole is arranged at the middle position of each cooling channel, and the thermocouple is installed on the temperature measuring hole.

[0017] Further, the mold has a vacuum pipeline interface hole, and the vacuum pipeline interface hole communicates with the molding cavity.

[0018] To achieve the above object, the present invention provides a method for preparing a resin casting body, which is characterized in that the above - mentioned resin casting body preparation device is used, and the preparation method includes:

[0019] Step 1: Place the mold in a heating environment, and inject resin into the molding cavity that has been pre - heated and evacuated.

[0020] Step 2: Heat the mold to the set process temperature, maintain the process pressure in the forming cavity through the side mold pressure chamber, monitor the thermocouple temperature at the i-th cooling channel partition among a total of n cooling channel partitions of the mold, calculate the deviation between the current mold temperature in this area and the set process temperature at this time. When the deviation at the i-th cooling channel partition is greater than the set safe temperature range, control the opening of the cooling pipeline cut-off valve corresponding to the i-th cooling channel partition, and introduce cooling fluid into the cooling inlet channel for cooling; when the monitored temperature deviation at the current cooling channel partition is less than the set safe temperature range, then close the cooling pipeline cut-off valve corresponding to the current cooling channel partition;

[0021] Step 3: If the cooling pipeline cut-off valves at all cooling channel partitions are not opened within the set monitoring time period, then increase the process temperature set in Step 2 to the next process holding point;

[0022] Step 4: Repeat the above Step 2 and Step 3. When the process temperature reaches the curing temperature of the resin, maintain the curing temperature until the end of the curing stage, and Step 2 continues to function during the curing process;

[0023] Step 5: Start cooling down and unload the process pressure in the forming cavity, monitor the thermocouple temperature at each cooling channel partition of the mold, calculate the average temperature of all monitored areas in real time, compare the deviation between the mold temperature at each cooling channel partition and the average temperature. Denote all the cooling channel partitions where the mold temperature is lower than the average temperature and the temperature deviation is greater than the set temperature range as set A, and the remaining cooling channel partitions as set B. Control the opening of the cooling pipeline cut-off valves corresponding to the cooling channel partitions in set B, and introduce cooling gas into the cooling inlet channel; when it is monitored that the temperature deviation at a certain cooling channel partition in set A changes from being greater than the set temperature range to being less than the set temperature range, then remove it from set A, add it to set B and open its corresponding cooling pipeline cut-off valve; when it is monitored that the temperature deviation at a certain cooling channel partition in set B changes from being less than the set temperature range to being greater than the set temperature range, then remove it from set B, add it to set A and close its corresponding cooling pipeline cut-off valve; if the temperature deviations at all cooling channel partitions are within the set temperature range, then close the cooling pipeline cut-off valves corresponding to all cooling channel partitions, and the mold is in a natural cooling state;

[0024] Step 6: Wait until the average process temperature drops to room temperature, then disassemble the mold and take out the cured resin casting in the forming cavity.

[0025] Further, it further includes a step of real-time monitoring of the pressure in the side mold pressure chamber in steps 2 to 4. If the pressure in the side mold pressure chamber rapidly increases, a signal to stop heating and raising the temperature is triggered, and an electro-hydraulic proportional valve is controlled to reduce the pressure in the side mold pressure chamber to the ambient pressure, maintaining an open state to relieve the pressure inside the mold.

[0026] The above technical solution of the present invention has the following advantages: On the one hand, since the mold has a forming cavity for forming a part and a side mold pressure chamber for regulating the pressure in the forming cavity, and the forming cavity and the side mold pressure chamber are separated by a pressure diaphragm, which can deform under a certain pressure. Therefore, the curing pressure can be ensured by controlling the pressure in the side mold pressure chamber, and the pores in the resin casting can be reduced. On the other hand, the aggregation of casting heat causing explosive polymerization can be prevented by controlling the heating rate, and the temperature uniformity of the mold during the cooling process can be controlled by cooling temperature control. Description of the Drawings

[0027] Figure 1 A mold for preparing a resin casting disclosed by the present invention.

[0028] Figure 2 An exploded view of a mold for preparing a resin casting disclosed by the present invention.

[0029] Figure 3 A bottom view of the lower mold of the forming mold disclosed by the present invention.

[0030] Figure 4 A cross-sectional view perpendicular to the length direction of a mold for preparing a resin casting disclosed by the present invention.

[0031] Figure 5 A cross-sectional view parallel to the length direction of a mold for preparing a resin casting disclosed by the present invention.

[0032] Figure 6 A front view of the pipeline connection of a mold for preparing a resin casting disclosed by the present invention.

[0033] Figure 7 A top view of the pipeline connection of a mold for preparing a resin casting disclosed by the present invention.

[0034] In the figure:

[0035] 10. Mold; 101. Upper pressing mold; 102. Upper mold of the forming mold; 103. Lower mold of the forming mold; 104. Lower pressing mold; 105. First side mold; 106. Second side mold; 101-1. Vertical bolt hole; 101-2. Vacuum pipeline interface hole; 101-3. Temperature measurement hole; 101-4. Cooling inlet; 101-5. Cooling return port; 102-1. Cooling channel; 103-1. Forming mold cavity; 103-2. Sealing groove; 103-3. Resin injection pipeline interface hole; 105-1. Horizontal bolt hole; 105-2. Mold pressure pipeline interface; 105-3. Side mold pressure cavity;

[0036] 11. Pressure diaphragm; 12. Pneumatic pipeline; 13. Gas source device; 14. Electric proportional valve; 15. Controller; 16. Pressure cut-off valve; 17. Cooler; 18. Cooling pipeline cut-off valve; 19. High-temperature curing environment box; 20. Cooling circulating air inlet pipeline; 21. Cooling circulating air return pipeline; 150. Industrial control computer; 151. Programmable logic controller. Specific embodiments

[0037] The following will further describe in detail the specific embodiments of the present invention in conjunction with the accompanying drawings and embodiments. The following embodiments are used to illustrate the present invention, but are not used to limit the scope of the present invention.

[0038] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0039] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0040] Figure 1 、 Figure 2 It is a schematic diagram of the hardware structure of a resin casting body preparation device according to one embodiment of the present invention. In Figure 1In the illustrated embodiment, the device includes a mold 10, where the mold 10 includes an upper pressing mold 101, an upper forming mold 102, a lower forming mold 103, a lower pressing mold 104, a first side mold 105, and a second side mold 106. Those skilled in the art can understand that Figure 1 , Figure 2 the specific structure of the preparation device shown in does not constitute a limitation on the preparation device. The preparation device may include more or fewer components than those shown in the figure, and some components are not essential components of the preparation device and can be completely omitted or combined according to needs within the scope of not changing the essence of the invention.

[0041] Hereinafter, the technical solution of the present disclosure will be described by taking a resin casting body preparation device disclosed in this application as an example.

[0042] According to an example of the present disclosure, from Figures 1-5 the structural diagram of a resin casting body preparation device shown, it can be seen that the mold 10 has a forming mold cavity 103-1 for forming a workpiece (i.e., a resin casting body) and a side mold pressure cavity 105-3 for regulating the pressure in the forming mold cavity 103-1. The mold 10 also has a resin injection pipeline interface hole 103-3 communicating with the forming mold cavity 103-1 to inject resin into the forming mold cavity 103-1 from the resin injection pipeline interface hole 103-3.

[0043] As Figure 4 shown, the forming mold cavity 103-1 and the side mold pressure cavity 105-3 are separated by a pressure diaphragm 11, so that the forming mold cavity 103-1 and the side mold pressure cavity 105-3 are not connected. The number of the side mold pressure cavity 105-3 and the pressure diaphragm 11 can be set to two groups according to needs, corresponding to the first side mold 105 and the second side mold 106. Taking one group as an example, a mold pressure pipeline interface 105-2 is opened on the first side mold 105, and an air pressure pipeline 12 is connected to the mold pressure pipeline interface 105-2 to guide gas to flow into or out of the side mold pressure cavity 105-3. In some embodiments, the pressure diaphragm 11 can deform under a certain pressure. When the other end of the air pressure pipeline 12 is connected to an air source device 13, gas can be input into the air pressure pipeline 12 by the air source device 13, so that the gas enters the side mold pressure cavity 105-3. After the high-pressure gas enters, the air pressure intensity in the side mold pressure cavity 105-3 causes the pressure diaphragm 11 to deform, and the pressure in the cavity is transmitted to the resin in the forming mold cavity 103-1 through the pressure diaphragm 11, thereby realizing pressure control and ensuring the curing pressure.

[0044] In the above embodiment, as Figure 6As shown, the electric proportional valve 14 is arranged on the air pressure pipeline 12, and is used to control the pressure of the side mold pressure chamber 105-3 according to the electrical signal; and the controller 15 can control the opening of the electric proportional valve 14 in the air pressure pipeline 12; in some embodiments, the controller 15 can be composed of an industrial control computer 150 and a programmable logic controller 151, and the industrial control computer 150 controls the electric proportional valve 14 through the programmable logic controller 151 to introduce high-pressure gas into the side mold pressure chamber 105-3 to maintain the pressure in the chamber.

[0045] In this embodiment, in addition to being used to isolate the molding cavity 103-1 and the side mold pressure cavity 105-3 and deforming under a certain pressure, the pressure diaphragm 11 also has the characteristic of rupturing after deformation limit; during the heating and curing process of the resin casting, if an explosion occurs, the high-pressure gas in the molding cavity 103-1 first destroys the pressure diaphragm 11 and enters the side mold pressure cavity 105-3. After the industrial control computer 150 monitors the rapid increase in the pressure in the side mold pressure cavity 105-3 through the electrical proportional valve 14, it triggers the high-temperature curing environment box 19 to stop heating and heating, and controls the electrical proportional valve 14 connected to the air pressure pipeline 12 to reduce the pressure in the side mold pressure cavity 105-3 to the ambient pressure, and maintains the normally open state to relieve the pressure inside the mold. In this embodiment, by using the pressure diaphragm 11 to relieve pressure when an explosion occurs, pressure accumulation in the mold can be avoided, thereby improving equipment safety, and reducing curing pores by applying pressure, thereby solving the problem that the current technology is difficult to prepare thick resin castings.

[0046] In at least one example of the pressure diaphragm 11 in the above embodiments, but not limited to, the pressure diaphragm 11 can be made of silicone rubber.

[0047] In at least one of the above embodiments, the pressure inside the mold is released after implosion occurs by using a pressure diaphragm that is destructible under extreme pressure. Implosion can also be prevented by controlling the heating rate.

[0048] For details, please refer to Figure 1 , Figure 2 The mold 10 has a plurality of cooling inlets 101-4 for directing the cooling fluid or cooling gas to flow to each individual cooling channel partition, and a plurality of cooling return ports 101-5 for directing the cooling fluid or cooling gas to flow back from the cooling channel partition. By controlling the cooling of the cooling channel partition, at any time during the resin heating and curing process, the heat generated by the curing in the mold cavity of the mold 10 can be locally controlled to avoid heat accumulation and explosion.

[0049] like Figure 6 , Figure 7, when it is necessary to control the local temperature inside the mold 10, each cooling inlet 101-4 is connected to the cooler 17 through a separate pipeline. A cooling pipeline stop valve 18 is provided on the pipeline where the cooling inlet 101-4 is separately connected to the cooler 17. The cooling pipeline stop valve 18 is controlled by the controller 15. Under the control of the controller 15, the pipeline is selectively conducted to separately cool the cooling channel partition that needs local temperature reduction.

[0050] Figure 6 The figure shows a cooling structure of this embodiment. Each cooling inlet 101-4 is connected to the cooler 17 through a separate cooling circulating air inlet pipeline 20, and each cooling return port 101-5 is connected to the cooler 17 through a separate cooling circulating air return pipeline 21. When the cooler 17 is a refrigeration circulating fan, the cold air flow formed by the refrigeration circulating fan flows through the cooling circulating air inlet pipeline 20 and enters the cooling channel 102-1 from the cooling inlet 101-4. After heat exchange, the air flow flows out from the cooling return port 101-5 through the cooling circulating air return pipeline 21.

[0051] In an example of this embodiment, such as Figure 3 shown, the cooling channel 102-1 is a "C"-shaped structure, a spiral structure, a meandering structure, etc. that are not connected end to end. A temperature measurement hole 101-3 is provided at the middle position of each cooling channel 102-1, and a temperature sensor is installed on the temperature measurement hole 101-3.

[0052] The controller 15 receives the signal that senses the internal temperature of the mold from the temperature sensor, and controls the cooler 17 and the cooling pipeline stop valve 18 according to the received signal. The temperature sensor can take a thermocouple as an example, and a temperature sensor is provided in each cooling channel partition of the mold 10.

[0053] As for the assembly relationship of the above-mentioned mold, the upper mold 101, the pressure diaphragm 11 and the first side mold 105 are fixed by fastening bolts passing through the connected horizontal bolt holes 105-1. The upper mold 101, the pressure diaphragm 11 and the second side mold 106 are fixed by fastening bolts passing through the connected horizontal bolt holes 105-1. The lower mold 104, the pressure diaphragm 11 and the first side mold 105 are fixed by fastening bolts passing through the connected horizontal bolt holes 105-1. The lower mold 104, the pressure diaphragm 11 and the second side mold 106 are fixed by fastening bolts passing through the connected horizontal bolt holes 105-1.

[0054] To achieve the assembly relationship of the above-mentioned mold, the upper pressing mold 101 and the upper mold 102 of the forming mold are fixed by fastening bolts passing through the connected vertical bolt holes 101-1, and the lower mold 103 of the forming mold and the lower pressing mold 104 are fixed by fastening bolts passing through the connected vertical bolt holes 101-1. The vacuum pipeline interface holes 101-2 on the upper pressing mold 101 and the upper mold 102 of the forming mold are through holes after the upper pressing mold 101 and the upper mold 102 of the forming mold are assembled, and are connected to the forming mold cavity 103-1 on the lower mold 103 of the forming mold.

[0055] Furthermore, the cooling inlet 101-4 and the cooling return port 101-5 on the lower pressing mold 104 are respectively connected to both ends of the cooling channel 102-1 of the lower mold 103 of the forming mold; the resin injection pipeline interface holes 103-3 on the lower pressing mold 104 and the lower mold 103 of the forming mold are through holes after the lower pressing mold 104 and the lower mold 103 of the forming mold are assembled, and are connected to the forming mold cavity 103-1 on the lower mold 103 of the forming mold; there are sealing grooves 103-2 at both ends of the lower mold 103 of the forming mold, and sealing strips are filled in the sealing grooves 103-2 during assembly.

[0056] Furthermore, the temperature measurement holes 101-3 on the upper pressing mold 101 and the upper mold 102 of the forming mold are through holes after the upper pressing mold 101 and the upper mold 102 of the forming mold are assembled, and the temperature measurement holes 101-3 on the lower pressing mold 104 and the lower mold 103 of the forming mold are through holes after the lower pressing mold 104 and the lower mold 103 of the forming mold are assembled, and the bottom ends of the temperature measurement holes 101-3 are not connected to the forming mold cavity 103-1.

[0057] Please refer to Figures 1-7 According to different requirements, the order of the steps of the present invention can be changed, and some steps can be omitted.

[0058] In an embodiment of the present application, a method for preparing a resin casting uses the preparation device in the above embodiment to prepare a resin casting, and the following is an example of the method for preparing a resin casting for explanation.

[0059] A method for preparing a resin casting includes the following steps:

[0060] Step 1: Place the mold in a heating environment and inject resin into the preheated and evacuated forming mold cavity.

[0061] Specifically, before preparation, it is necessary to assemble the mold for preparing the resin casting body. Place the sealing strip into the sealing groove 103-2 of the lower mold 103 of the forming mold; fix and connect the upper pressing mold 101, the upper mold 102 of the forming mold, the lower mold 103 of the forming mold, and the lower pressing mold 104 through the vertical bolt holes 101-1 with fastening bolts; install the pressure diaphragms 11 on both sides and fix and connect the first side mold 105 and the second side mold 106 through the horizontal bolt holes 105-1 with fastening bolts. Thus, the assembly of the mold for preparing the resin casting body is completed.

[0062] Place the assembled mold for preparing the resin casting body into the high-temperature curing environment box 19. Connect thermocouples to all the temperature measuring holes 101-3. Connect all the cooling inlet ports 101-4 to the cooling circulating air inlet pipeline 20 of the cooler 17 (i.e., the refrigeration cycle fan), connect the cooling return port 101-5 to the cooling circulating air return pipeline 21 of the cooler 17 (i.e., the refrigeration cycle fan), and electrically connect the cooling pipeline stop valve 18 to the programmable logic controller 151 and the industrial control computer 150.

[0063] Connect the mold pressure pipeline interface 105-2 to the pressure stop valve 16, the electro-hydraulic proportional valve 14, and the gas source device 13. Control the electro-hydraulic proportional valve 14 connected through the programmable logic controller 151 to maintain the pressure in the side mold pressure chamber 105-3 at the ambient pressure.

[0064] Close the cooling pipeline stop valve 18 and the cooler 17 (i.e., the refrigeration cycle fan), and preheat the mold; after the mold reaches the preheating temperature, evacuate the inside of the mold through the vacuum source connected to the vacuum pipeline interface hole 101-2; after the mold evacuation is completed, inject the resin after vacuum degassing into the forming mold cavity 103-1 along the injection pipeline interface hole 103-3, and close the stop valve at the vacuum pipeline interface hole 103-3 and the resin injection pipeline interface hole 103-3.

[0065] Step 2: Raise the temperature of the mold to the set process temperature, and maintain the process pressure of the forming mold cavity through the side mold pressure chamber. Monitor the temperature of the thermocouple at the i-th cooling flow channel partition in a total of n cooling flow channel partitions of the mold, and calculate the deviation between the current mold temperature in this area and the set process temperature at this time. When the deviation at the i-th cooling flow channel partition is greater than the set safe temperature range, control the opening of the cooling pipeline stop valve corresponding to the i-th cooling flow channel partition, and introduce cooling fluid into the cooling inlet channel for cooling; when the monitored temperature deviation at the current cooling flow channel partition is less than the set safe temperature range, then close the cooling pipeline stop valve corresponding to the current cooling flow channel partition.

[0066] Specifically, during the mold heating-up stage, the cooler 17 (i.e., the refrigeration cycle blower) is turned on. The industrial control computer 150 controls the electric proportional valve 14 through the programmable logic controller 151 to introduce high-pressure gas into the side mold pressure chamber 105-3, maintaining the pressure in the chamber at the set process pressure Pt. The pressure in the chamber is transmitted to the resin in the forming mold cavity 103-1 through the pressure diaphragm 11. The industrial control computer 150 monitors the thermocouple temperature Ti at the i-th cooling channel partition of the mold, and calculates the deviation △Ti = |Ti - Tt| between the current mold temperature in this area and the set process temperature Tt at this moment. When the temperature deviation △Ti of the i-th area is greater than the set safety temperature Ts, the industrial control computer 150 controls the opening of the cooling pipeline cut-off valve 18 corresponding to the i-th cooling air flow channel partition, and cools the cooling channel 102-1 by introducing cooling gas. When the monitored temperature deviation △Ti at the current cooling channel partition is less than Ts, the cooling pipeline cut-off valve 18 corresponding to the current cooling air flow channel partition is closed.

[0067] Step 3: If the cooling pipeline cut-off valves at all cooling channel partitions are not opened during the set monitoring time period, then increase the process temperature set in Step 2 to the next process heat preservation point.

[0068] Step 4: Repeat the above Steps 2 and 3. When the process temperature reaches the curing temperature of the resin, maintain the curing temperature until the end of the curing stage; Step 2 continues to function during the curing process.

[0069] Specifically, the industrial control computer 150 maintains the set process temperature Tt unchanged, the cooling pipeline cut-off valves 18 at the cooling channel partitions are closed, and if the cooling pipeline cut-off valves 18 at all cooling channel partitions are not opened during the set monitoring time △t, then the process temperature Tt can be increased by △T to the next process heat preservation point.

[0070] Repeat the above Steps 2 and 3 until the process temperature Tt reaches the curing temperature Tc and no longer continues to rise. Maintain the curing temperature according to Step 2 until the end of the curing stage. The industrial control computer 150 controls the electric proportional valve 14 to unload the pressure in the side mold pressure chamber 105-3, and starts the mold cooling process; Step 2 continues to function during the curing process.

[0071] Step 5, start cooling and unloading the process pressure of the molding cavity, monitor the thermocouple temperature Ti of the mold at each cooling channel partition, calculate the average temperature Tm of all monitoring areas in real time, compare the deviation between the mold temperature at each cooling channel partition and the average temperature △Ti=|Tm-Ti|, and record all cooling channel partitions whose mold temperatures are lower than the average temperature (Ti<Tm) and whose temperature deviation is greater than the set temperature range (△Ti>Td) as set A, and the remaining cooling channel partitions as set B. The cooling pipeline stop valve corresponding to the cooling channel partition in the control set B is opened, and cooling gas is introduced into the cooling inlet channel; when the temperature deviation △Ti at a cooling channel partition in the monitoring set A changes from greater than the set temperature range Td to less than the set temperature range Td, it is removed from the set A, added to the set B and the corresponding cooling pipeline stop valve is opened; when the temperature deviation △Ti at a cooling channel partition in the monitoring set B changes from less than the set temperature range Td to greater than the set temperature range Td, it is removed from the set B, added to the set A and the corresponding cooling pipeline stop valve is closed; if the temperature deviation △Ti at all cooling channel partitions is within the set temperature range Td, the cooling pipeline stop valves corresponding to all cooling channel partitions are closed, and the mold is in a natural cooling state;

[0072] Step 6: When the average process temperature drops to room temperature, the mold is removed to take out the cured resin casting in the molding cavity.

[0073] As a preferred example of this embodiment, if an explosion occurs during the heating and curing process of the resin casting, the high-pressure gas first destroys the pressure diaphragm 11 and enters the side mold pressure chamber 105-3. After the industrial control computer 150 monitors the rapid increase in pressure in the side mold pressure chamber 105-3 through the electrical proportional valve 14, the high-temperature curing environment box 19 is triggered to stop heating and the electrical proportional valve 14 connected to the mold pressure pipeline interface 105-2 is controlled to reduce the pressure in the side mold pressure chamber 105-2 to the ambient pressure, and maintains the normally open state to relieve the pressure inside the mold.

[0074] This embodiment is based on pressurizing the side mold pressure cavity 105-3, using a silicone rubber membrane for pressurization control to ensure the curing pressure and reduce the curing porosity; a pressure maintenance pipeline is used to release the pressure during implosion. In addition, the heating rate can be controlled to prevent the accumulation of casting heat from causing implosion, and the uniformity of the mold temperature during the cooling process can be controlled by cooling temperature control.

[0075] In the specification and claims of the present application, the words "include / comprise" and the words "have / include" and their variations are used to specify the existence of stated features, values, steps or components, but do not exclude the existence or addition of one or more other features, values, steps, components or combinations thereof.

[0076] For clarity of illustration, some features of the present invention are described in separate embodiments. However, these features may also be described in a single embodiment in combination. Conversely, for the sake of brevity, some features of the present invention are described only in a single embodiment. However, these features may also be described separately or in any suitable combination in different embodiments.

[0077] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for preparing a resin casting body, characterized in that, The preparation device includes: A mold, having a forming cavity for forming a workpiece and a side mold pressure cavity for regulating the pressure in the forming cavity. The mold also has a resin injection pipeline interface hole communicating with the forming cavity to inject resin into the forming cavity from the resin injection pipeline interface hole; A pressure diaphragm, used to isolate the forming cavity and the side mold pressure cavity and deform under a certain pressure; An air pressure pipeline, guiding gas to flow into or out of the side mold pressure cavity; An air source device, which is communicated with the air pressure pipeline and used to input gas into the air pressure pipeline; An electro-pneumatic proportional valve, which is arranged on the air pressure pipeline and used to control the pressure in the side mold pressure cavity according to an electric signal; and A controller, which controls the opening degree of the electro-pneumatic proportional valve in the air pressure pipeline; The preparation method includes the following steps: Step 1: Place the mold in a heating environment and inject resin into the preheated and evacuated forming cavity; Step 2: Raise the temperature of the mold to the set process temperature, and maintain the process pressure of the forming cavity through the side mold pressure cavity. Monitor the thermocouple temperature at the ith cooling channel partition in a total of n cooling channel partitions of the mold, calculate the deviation between the current mold temperature in this area and the set process temperature at this time. When the deviation at the ith cooling channel partition is greater than the set safe temperature range, control the cooling pipeline cut-off valve corresponding to the ith cooling channel partition to open, and introduce a cooling fluid into the cooling inlet channel for cooling; when the monitored temperature deviation at the current cooling channel partition is less than the set safe temperature range, then close the cooling pipeline cut-off valve corresponding to the current cooling channel partition; Step 3: If the cooling pipeline cut-off valves at all cooling channel partitions do not open within the set monitoring time period, then increase the process temperature set in Step 2 to the next process holding point; Step 4: Repeat the above Steps 2 and 3. When the process temperature reaches the curing temperature of the resin, maintain the curing temperature until the end of the curing stage, and Step 2 continues to function during the curing process; Step 5: Start to cool down and unload the process pressure of the forming cavity. Monitor the thermocouple temperature at each cooling channel partition of the mold, calculate the average temperature of all monitored areas in real time, compare the deviation between the mold temperature at each cooling channel partition and the average temperature. Denote all the cooling channel partitions where the mold temperature is lower than the average temperature and the temperature deviation is greater than the set temperature range as set A, and the remaining cooling channel partitions as set B; control the cooling pipeline cut-off valves corresponding to the cooling channel partitions in set B to open, and introduce a cooling gas into the cooling inlet channel; when it is monitored that the temperature deviation at a certain cooling channel partition in set A changes from being greater than the set temperature range to being less than the set temperature range, then remove it from set A, add it to set B and open its corresponding cooling pipeline cut-off valve; when it is monitored that the temperature deviation at a certain cooling channel partition in set B changes from being less than the set temperature range to being greater than the set temperature range, then remove it from set B, add it to set A and close its corresponding cooling pipeline cut-off valve; if all If the temperature deviation at the cooling channel partition is within the set temperature range, the cooling pipeline stop valves corresponding to all cooling channel partitions are closed, and the mold is in a natural cooling state; Step 6: When the average process temperature drops to room temperature, remove the mold and take out the cured resin casting in the forming cavity; It also includes real-time monitoring of the pressure in the side mold pressure cavity in Steps 2-4. If the pressure in the side mold pressure cavity rises rapidly, a stop heating and rising signal is triggered, and the electro-hydraulic proportional valve is controlled to reduce the pressure in the side mold pressure cavity to the ambient pressure, and it is maintained in an open state to relieve the pressure inside the mold.

2. The method for preparing a resin casting body according to claim 1, wherein The pressure diaphragm is used to isolate the forming cavity and the side mold pressure cavity and rupture after reaching the deformation limit under a certain pressure.

3. The method for preparing a resin casting body according to claim 1, characterized in that The pressure diaphragm is silicone rubber.

4. The method for preparing a resin casting body according to claim 1, characterized in that, The mold has multiple cooling inlets to guide the cooling fluid or cooling gas to each individual cooling channel partition; each of the cooling inlets is connected to a cooler through a separate pipeline, and a cooling pipeline stop valve is provided on the pipeline connecting the cooling inlet and the cooler separately. The cooling pipeline stop valve is controlled by the controller and selectively conducts the pipeline to cool the cooling channel partition separately under the control of the controller.

5. The preparation method of a resin casting body according to claim 4, wherein, The device also includes multiple thermocouples, which are connected to the controller and used to sense the temperature of each cooling channel partition and send an electrical signal of sensing the temperature of each cooling channel partition to the controller.

6. The method for preparing a resin casting body according to claim 4, wherein, The mold has multiple cooling return ports to guide the cooling fluid or cooling gas to flow back from the cooling channel partition to the cooler.

7. A method for preparing a resin casting body according to claim 5, characterized in that, Multiple cooling channels are arranged in the mold and are respectively communicated with the cooling inlets and the cooling return ports. The cooling channels are at least one of a "C" type structure, a spiral structure, or a meandering structure that are not connected at the head and tail. A temperature measurement hole is arranged at the middle position of each cooling channel, and the thermocouple is installed on the temperature measurement hole.

8. The preparation method of a resin casting body according to claim 1, characterized in that, The mold has a vacuum pipeline interface hole, and the vacuum pipeline interface hole is communicated with the forming cavity.

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