A HP-RTM glue injection machine suitable for polyurethane and epoxy resin dual raw material system

Abstract

The application discloses a HP-RTM glue injection machine suitable for a polyurethane and epoxy resin double raw material system, relates to the field of molding forming technology, and comprises a first material tank, a second material tank, a mixing head, two groups of first booster pumps, first filters, first pressure sensors, metering pump groups, second pressure sensors, second filter groups and first flow meters which are sequentially connected. The metering pump group comprises at least two parallel first metering pumps, and the displacement of any two first metering pumps is different. The second filter group comprises at least two parallel second filters. The application is used for solving the problem that the prior art cannot use a universal pumping system due to different raw material systems, thereby resulting in high economic cost, and achieves the purpose of meeting the production operation of different raw material systems through one production line.

Description

Technical Field

[0001] This invention relates to the field of molding technology, specifically to an HP-RTM dispensing machine suitable for a dual-raw material system of polyurethane and epoxy resin. Background Technology

[0002] HP-RTM (High Pressure-Resin Transfer Molding) is a process that involves injecting high-pressure mixed resin into a closed mold to impregnate reinforcing materials (such as carbon fiber and glass fiber) and then curing it. Its core feature is the use of high-pressure injection equipment to mix the raw materials and rapidly inject them into the mold. Combined with a fast-curing material system, this significantly reduces the molding cycle of traditional RTM processes from several hours to just a few minutes. The main advantages of HP-RTM include the ability to manufacture high-quality, high-precision components with low porosity and high fiber content, as well as closed-mold operation and minimal pollution. This technology has been increasingly adopted in recent years in fields such as rail transportation and the automotive industry. In HP-RTM, the two raw materials are circulated and mixed in a mixing head. The self-circulation or mixed injection mode can be switched by adjusting the piston position inside the mixing head.

[0003] The HP-RTM process involves at least two raw material systems: epoxy resin and polyurethane. The formulations of these two systems differ significantly. For example, the epoxy resin system's ratio is approximately epoxy resin:curing agent:internal release agent = 100:15~18:2.5, while the polyurethane system's ratio is approximately polyether:isocyanate 100:95~110. This significant difference in formulation complicates the use of interchangeable pumping systems. Furthermore, the isocyanate in the polyurethane system and the ammonium salt in the curing agent of the epoxy resin system can react chemically, which is another key reason why the pumping systems for the two raw material systems are not interchangeable in existing technologies.

[0004] Therefore, existing technologies, both domestically and internationally, cannot use the same production system for both epoxy resin and polyurethane raw material systems. To produce epoxy resin and polyurethane, two independent production lines are typically required. However, each production line can cost tens of millions of yuan, which undoubtedly imposes significant economic burdens on manufacturers. Summary of the Invention

[0005] This invention provides an HP-RTM dispensing machine suitable for dual raw material systems of polyurethane and epoxy resin, to solve the problem of high economic cost caused by the inability to use the same pumping system for different raw material systems in the HP-RTM process in the prior art, and to achieve the goal of meeting the production operations of different raw material systems through a single production line.

[0006] This invention is achieved through the following technical solution:

[0007] An HP-RTM dispensing machine suitable for a polyurethane and epoxy resin dual-raw material system includes a first material tank, a second material tank, and a mixing head. The mixing head includes a first feeding channel, a second feeding channel, a first loop channel, and a second loop channel. The output end and input end of the first material tank are respectively connected to the first feeding channel and the first loop channel, and the output end and input end of the second material tank are respectively connected to the second feeding channel and the second loop channel.

[0008] Between the output end of the first material tank and the first feed channel, and between the output end of the second material tank and the second feed channel, there are a first booster pump, a first filter, a first pressure sensor, a metering pump group, a second pressure sensor, a second filter group, and a first flow meter connected in sequence.

[0009] The metering pump group includes at least two first metering pumps connected in parallel, and any two of the first metering pumps have different displacements.

[0010] The second filter group includes at least two second filters connected in parallel.

[0011] To address the issue of high economic costs caused by the inability to use a universal pumping system for different raw material systems in the existing HP-RTM process, this invention proposes an HP-RTM dispensing machine suitable for both polyurethane and epoxy resin dual raw material systems. The first and second material tanks are used to hold the corresponding main raw materials for different raw material systems; for example, for the polyurethane system, the first material tank holds isocyanate, and the second material tank holds a polyether blend; for the epoxy resin system, the first material tank holds epoxy resin, and the second material tank holds a curing agent. The first feed channel, second feed channel, first loop channel, and second loop channel on the mixing head are all existing technologies. When casting is required, the two raw materials are mixed in the mixing head and output to the mold; during self-circulation, the two raw materials flow back to their respective material tanks through the mixing head.

[0012] This application provides, between the output end of the first material tank and the first feed channel, and between the output end of the second material tank and the second feed channel, a first booster pump, a first filter, a first pressure sensor, a metering pump group, a second pressure sensor, a second filter group, and a first flow meter, connected in sequence. The metering pump group includes at least two first metering pumps connected in parallel, and the second filter group includes at least two second filters connected in parallel. In the metering pump group, the displacement of any two first metering pumps is different.

[0013] The system includes: a first booster pump for pressurizing and pumping raw materials into the corresponding tank; a first filter for initial filtration of the raw materials and breaking up residual air bubbles; a first pressure sensor for monitoring the output pressure of the first booster pump; a metering pump for precisely pumping the raw materials according to the required proportions; a second pressure sensor for monitoring the input pressure of the metering pump to ensure the high-pressure conditions required for HP-RTM operation; a second filter for secondary filtration of the raw materials and further breaking up residual air bubbles; and a first flow meter for final monitoring of the raw materials about to enter the mixing head and for feedback control of the metering pump to ensure accurate proportions of the mixture.

[0014] In practical use, this application allows for the switching of metering pumps with different displacements within the metering pump set, enabling different metering pumps to meet the pumping requirements of different raw material systems. Only the first and second material tanks containing the different raw materials need to be replaced. Furthermore, the isocyanate in the polyurethane system and the curing agent in the epoxy resin system enter the mixing head through completely different pipelines. Even when switching raw material systems, only routine cleaning of the pipelines and the inside of the mixing head is required. Therefore, this application has extremely low cleaning requirements when switching raw material systems, enabling rapid and efficient switching between polyurethane and epoxy resin systems. This significantly improves the versatility of the HP-RTM equipment and significantly reduces the economic costs for manufacturers, demonstrating substantial economic value.

[0015] Furthermore, this application allows for switching between different second filters depending on the raw material system. Because the second filter in this application has a higher filtration level than the first filter, meaning its filter element has smaller pores, it is difficult to perform thorough self-cleaning, which can easily lead to adverse consequences when switching between different raw material systems.

[0016] Furthermore, the second filter is prone to clogging under continuous production conditions in HP-RTM. This application can also provide a larger number of second filters for backup. When the currently used second filter becomes clogged and needs to be replaced, it can be flexibly switched to other second filters that are compatible with the same system, thereby ensuring continuous operation and improving production efficiency.

[0017] Furthermore, the upstream and downstream ends of the metering pump group are both controlled by a first reversing valve; the upstream and downstream ends of the second filter group are both controlled by a second reversing valve.

[0018] That is, the first reversing valve at both the upstream and downstream ends of the metering pump set controls which metering pump the fluid will be pumped through; and the second reversing valve at both the upstream and downstream ends of the second filter set controls which second filter the fluid will flow through.

[0019] Furthermore, it also includes a third material tank, and between the output end of the third material tank and the first feed channel, there are a second booster pump, a third filter, a third pressure sensor, a second metering pump, a fourth pressure sensor, a fourth filter and a second flow meter connected in sequence.

[0020] For epoxy resin raw material systems, an internal release agent needs to be added to facilitate subsequent demolding. Although it can be added directly to the corresponding first material tank, problems such as uneven mixing and inaccurate ratio control exist. To overcome this problem, this solution also includes a third material tank for holding the internal release agent. When the epoxy resin raw material system is needed, it is prepared through the third material tank and then pumped sequentially through a second booster pump, a third filter, a third pressure sensor, a second metering pump, a fourth pressure sensor, a fourth filter, and a second flow meter to the first feed channel of the mixing head. This allows the internal release agent and epoxy resin to mix at the inlet of the mixing head. This feeding method ensures that the internal release agent and epoxy resin are added accurately according to the specified ratio and helps to ensure uniform mixing.

[0021] Furthermore, there are at least two mixing heads; the first material tank, the second material tank, and the third material tank are all connected to each mixing head, and the flow direction is controlled by the third reversing valve, the fourth reversing valve, and the fifth reversing valve, respectively.

[0022] During its research, the applicant also discovered that the HP-RTM process requires approximately 10 minutes of curing time during production. During this period, the mixing head must remain connected to the mold and cannot be removed for subsequent operations. Therefore, this waiting time is completely wasted, hindering continuous operation and resulting in insufficient production efficiency. To overcome this problem, this application is equipped with at least two mixing heads, with the first, second, and third material tanks connected to each mixing head via pipelines. When one mixing head completes its pouring operation and enters the waiting time, it can immediately switch to another mixing head to inject the mixed raw material into another mold. Based on this principle, continuously switching between mixing heads achieves true continuous production, avoiding the waiting time during raw material curing and significantly improving production efficiency.

[0023] In this scheme, the flow of raw materials pumped from the first tank to a specific mixing head is controlled by the third reversing valve; similarly, the flow of raw materials pumped from the second tank to a specific mixing head is controlled by the fourth reversing valve, and the flow of raw materials pumped from the third tank to a specific mixing head is controlled by the fifth reversing valve.

[0024] Furthermore, both the first and second material tanks are equipped with degassing mechanisms;

[0025] The degassing mechanism includes a negative pressure extraction device, a stirring device, and several degassing umbrella groups arranged vertically.

[0026] The debubbling umbrella assembly includes an upper guide plate and a lower guide plate that are coaxially distributed vertically. The upper guide plate gradually slopes downward from the inside to the outside in the radial direction, and the lower guide plate gradually slopes downward from the outside to the inside in the radial direction. The outer diameter of the bottom end of the upper guide plate is smaller than the outer diameter of the top end of the corresponding lower guide plate. The bottom end of the lower guide plate is provided with a flow channel.

[0027] This solution uses corresponding degassing mechanisms in the first and second material tanks to degas the raw materials, significantly reducing residual gas in the raw materials. This overcomes problems such as rough product surface, poor smoothness, and unpleasant feel in existing technologies, thereby improving the yield rate.

[0028] The degassing mechanism utilizes a negative pressure extraction device to maintain a negative pressure state inside the first and second material tanks, facilitating the rapid removal of gas from the raw materials and improving the degassing effect. During feeding or self-circulation, the raw materials enter from the top of the tanks and flow sequentially through each degassing umbrella group from top to bottom. For any given degassing umbrella group, the upper guide plate is located above the corresponding lower guide plate. The raw materials first flow to the surface of the upper guide plate, then flow downwards and outwards along its surface. They then drip from the edge of the upper guide plate to the lower guide plate, flowing downwards and inwards along its surface, and finally dripping down from the lower guide plate's flow channel onto the next lower degassing umbrella group. The raw materials dripping from the bottommost degassing umbrella group enter the corresponding tank bottom area.

[0029] The degassing mechanism, through the cooperation of a negative pressure extraction device and several degassing umbrella groups, can increase the travel distance of the raw material during its entry into the tank, allowing the raw material to flow a longer distance in a thin layer under negative pressure, which is more conducive to removing the gas inside the raw material.

[0030] The radial dimensions of the debubbling umbrella assembly can be adapted to specific needs; for example, the outer diameter of the lower guide plate can be made slightly smaller than the corresponding inner diameter of the tank.

[0031] Furthermore, the mixing head includes a nozzle, a piston cylinder, and a piston located inside the piston cylinder, the piston dividing the interior of the piston cylinder into a first chamber near the nozzle and a second chamber away from the nozzle.

[0032] It also includes a channel disposed inside the piston cylinder, the two ends of the channel being connected to the first cavity and the second cavity respectively; the piston cylinder is respectively provided with a first fluid inlet and a second fluid inlet communicating with the first cavity and the second cavity; the diameter of the channel is smaller than the diameter of the first fluid inlet and the second fluid inlet.

[0033] During the research process, the applicant also discovered that in the prior art, the piston inside the mixing head is driven by hydraulic oil to reciprocate. Under continuous production conditions, some hydraulic oil always remains between the piston's internal cavity and the upstream pipeline, constantly flowing back and forth. It cannot flow back to the hydraulic station for heat exchange, causing the oil temperature of this part of the hydraulic oil to rise continuously, which in turn causes local heating of the mixing head body. This is not conducive to the precise control of the actuators, nor to the precise control of the raw material mixing temperature, thus affecting production quality.

[0034] To overcome the aforementioned problems, this solution improves and optimizes the existing mixing head. Specifically, a channel is provided inside the piston cylinder, ensuring that both ends of this channel connect to the first and second chambers on either side of the piston, regardless of the piston's position within its stroke range. During continuous production, when sufficient hydraulic oil return is required, hydraulic oil is injected into the other chamber when the piston is at one end of its stroke. The injected hydraulic oil enters the channel and flows through it into the other chamber, from where it returns to the hydraulic station. During this process, the hydraulic oil remaining in the first and / or second chambers, as well as the hydraulic oil remaining in the upstream pipeline of the mixing head, can return to the hydraulic station for full circulation, thereby exchanging heat effectively with the remaining hydraulic oil in the station. This ensures uniform hydraulic oil temperature and overcomes the problem of excessively high residual hydraulic oil temperature affecting production quality. The above-mentioned "when it is necessary to ensure sufficient hydraulic oil return" can be controlled by real-time monitoring of the hydraulic oil temperature in the first chamber and / or the second chamber and / or the upstream pipeline of the mixing head. It can also be controlled periodically or quantitatively according to specific production conditions, without specific limitations here.

[0035] It should be noted that when adjusting the piston position using the mixing head of this application, the channel can be cut off or closed.

[0036] Furthermore, the mixing head also includes a throttling element for throttling the channel and an adjustment mechanism for adjusting the throttling element;

[0037] The channel includes at least one corner, and the throttling element is partially located at one corner;

[0038] The throttling element includes a throttling section, a sealing section, and an adjusting section arranged in sequence;

[0039] The throttling section is located at the corner and is tapered. The outer diameter of the tapered section gradually decreases from the end near the sealing section to the end away from the sealing section. The outer diameter of the tapered section near the sealing section is larger than the inner diameter of the channel, and the outer diameter of the tapered section away from the sealing section is smaller than the inner diameter of the channel.

[0040] The sealing part is dynamically sealed to the piston cylinder.

[0041] The adjusting part is threadedly fitted to the piston cylinder.

[0042] This solution uses a throttling element to throttle the channel, and the throttling element can be flexibly adjusted by an adjustment mechanism. This allows for flexible adjustment of the channel diameter when oil return is required, making it more flexible to adapt to different piston cylinders and significantly improving the versatility and flexibility of this application.

[0043] This solution also defines the specific structure of the throttling element. The throttling section achieves the blocking or closing of the channel, the sealing section achieves the sealing between the throttling element and the piston cylinder, and the adjusting section achieves the specific adjustment operation. Specifically, the tapered throttling section can completely block the channel at its corners. When it is necessary to open or close the channel, simply controlling the rotation of the adjusting section achieves the axial movement of the entire throttling element.

[0044] Furthermore, both the sealing part and the adjusting part are columnar; the outer wall of the adjusting part is provided with external threads, and the surface of the piston cylinder is provided with a mounting hole for installing the throttling element, and the inner wall of the mounting hole is provided with an internal thread that matches the external threads.

[0045] Furthermore, the piston includes a protrusion that dynamically seals with the inner wall of the piston cylinder; the piston has notches on both sides of the protrusion along the axial direction. These notches on both sides of the protrusion ensure that the channel remains connected even when the piston moves to the end of its stroke, thereby ensuring a stable oil return function.

[0046] Furthermore, a negative pressure sensor is provided on the nozzle end face.

[0047] During the research process, the applicant also discovered that existing RTM processes all involve adding pressure sensors to the mold to monitor the internal pressure, which leads to distorted pressure data and can result in poor wetting of fiber materials and a high scrap rate. The reason for this is that existing pressure sensors are installed on the pipeline between the mold and the vacuum pump, measuring the pressure within the pipeline rather than the pressure inside the mold, potentially causing data distortion. To overcome this problem, this solution installs a pressure sensor on the nozzle end face. When the nozzle is inserted into the mold, the pressure sensor on the nozzle directly monitors the internal pressure, effectively overcoming the problem of distorted monitoring data. Furthermore, it avoids the problems of clogging and mold modification required by adding pressure sensors to the mold in existing technologies, significantly reducing operating and equipment maintenance costs.

[0048] Compared with the prior art, the present invention has at least the following advantages and beneficial effects:

[0049] 1. The present invention provides an HP-RTM dispensing machine applicable to dual raw material systems of polyurethane and epoxy resin. It can quickly and efficiently switch between two different raw material systems of polyurethane and epoxy resin through two sets of pumping systems, which significantly improves the versatility of HP-RTM equipment and significantly reduces the economic cost of manufacturers, thus having great economic value.

[0050] 2. The present invention provides an HP-RTM dispensing machine suitable for a dual raw material system of polyurethane and epoxy resin. Through a third material tank and its downstream equipment, it ensures that the internal release agent and epoxy resin are added accurately according to the specified ratio requirements, and helps to ensure uniform mixing in the epoxy resin raw material system.

[0051] 3. The present invention provides an HP-RTM dispensing machine suitable for a dual raw material system of polyurethane and epoxy resin. It can continuously switch between mixing heads to work, truly realizing continuous production, avoiding waiting during the curing of raw materials, and significantly improving production efficiency.

[0052] 4. The present invention provides an HP-RTM dispensing machine suitable for a dual raw material system of polyurethane and epoxy resin. The degassing mechanism, through the cooperation of a negative pressure extraction device and several degassing umbrella groups, can increase the stroke of the raw material during the process of entering the material tank, so that the raw material flows a longer distance in a thin layer under negative pressure, thereby significantly improving the degassing effect.

[0053] 5. This invention provides an HP-RTM dispensing machine suitable for a dual-raw material system of polyurethane and epoxy resin. By improving and optimizing the mixing head, the hydraulic oil remaining in the internal cavity of the piston cylinder and the hydraulic oil remaining in the upstream pipeline of the mixing head can be returned to the hydraulic station for full circulation. This allows for sufficient heat exchange with the remaining hydraulic oil in the station, ensuring uniform hydraulic oil temperature and overcoming the problem of excessively high residual hydraulic oil temperature affecting production quality.

[0054] 6. The present invention provides an HP-RTM dispensing machine suitable for a dual raw material system of polyurethane and epoxy resin. It can monitor the vacuum state inside the mold in real time before dispensing and can also monitor the dynamic changes of pressure inside the mold in real time during dispensing. At the same time, it ensures the authenticity and reliability of the monitoring data, which helps to ensure that the product yield is maintained at a high level and significantly reduces operating costs and equipment maintenance costs. Attached Figure Description

[0055] The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and form part of this application, do not constitute a limitation thereof. In the drawings:

[0056] Figure 1 This is an overall schematic diagram of a specific embodiment of the present invention;

[0057] Figure 2 This is a schematic diagram of the first or second material tank in a specific embodiment of the present invention;

[0058] Figure 3 This is a schematic diagram of the mixing head in a specific embodiment of the present invention;

[0059] Figure 4 This is a partial cross-sectional view of the piston cylinder in a specific embodiment of the present invention;

[0060] Figure 5 for Figure 4 A magnified view of a section at point A in the middle;

[0061] Figure 6 for Figure 4 A magnified view of a section at point B in the middle.

[0062] The attached diagram shows the markings and corresponding component names:

[0063] 1-Mixing head, 101-Piston cylinder, 102-Piston, 1021-Protrusion, 103-First cavity, 104-Second cavity, 105-Nozzle, 106-Channel, 107-First fluid inlet / outlet, 108-Second fluid inlet / outlet, 109-Throttling element, 1091-Throttling part, 1092-Sealing part, 1093-Adjusting part, 110-Mounting hole, 111-Adjusting nut, 112-Negative pressure sensor, 113-First feed channel, 114-Second feed channel, 115-First loop channel, 116-Second loop channel;

[0064] 2-First material tank, 3-Second material tank, 4-First booster pump, 5-First filter, 6-First pressure sensor, 7-First metering pump, 8-Second pressure sensor, 9-Second filter, 10-First flow meter, 11-First reversing valve, 12-Second reversing valve, 13-Third material tank, 14-Second booster pump, 15-Third filter, 16-Third pressure sensor, 17-Second metering pump, 18-Fourth pressure sensor, 19-Fourth filter, 20-Second flow meter, 21-Third reversing valve, 22-Fourth reversing valve, 23-Fifth reversing valve, 24-Negative pressure extraction device, 25-Stirring device, 26-Upper guide plate, 27-Lower guide plate, 28-Sixth reversing valve, 29-Seventh reversing valve. Detailed Implementation

[0065] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments and accompanying drawings. The illustrative embodiments and descriptions of this invention are for explaining the invention only and are not intended to limit the invention. In the description of this application, it should be understood that terms such as "front," "rear," "left," "right," "upper," "lower," "vertical," "horizontal," "high," "low," "inner," and "outer," indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the scope of protection of this application.

[0066] Example 1:

[0067] like Figure 1 and Figure 3 The HP-RTM dispensing machine shown is suitable for a dual raw material system of polyurethane and epoxy resin. It includes a first material tank 2, a second material tank 3, and a mixing head 1. The mixing head 1 includes a first feeding channel 113, a second feeding channel 114, a first loop channel 115, and a second loop channel 116. The output end and input end of the first material tank 2 are connected to the first feeding channel 113 and the first loop channel 115, respectively. The output end and input end of the second material tank 3 are connected to the second feeding channel 114 and the second loop channel 116, respectively.

[0068] Between the output end of the first material tank 2 and the first feed channel 113, and between the output end of the second material tank 3 and the second feed channel 114, there are sequentially connected components such as a first booster pump 4, a first filter 5, a first pressure sensor 6, a metering pump group, a second pressure sensor 8, a second filter group, and a first flow meter 10.

[0069] The metering pump group includes at least two first metering pumps 7 connected in parallel, and the displacement of any two first metering pumps 7 is different; the second filter group includes at least two second filters 9 connected in parallel.

[0070] The second filter 9 has a higher filtration level than the first filter 5.

[0071] The upstream and downstream ends of the metering pump group are both controlled by the first reversing valve 11; the upstream and downstream ends of the second filter group are both controlled by the second reversing valve 12.

[0072] It also includes a third material tank 13, and between the output end of the third material tank 13 and the first feed channel 113, there are a second booster pump 14, a third filter 15, a third pressure sensor 16, a second metering pump 17, a fourth pressure sensor 18, a fourth filter 19 and a second flow meter 20 connected in sequence.

[0073] There are at least two mixing heads 1; the first material tank 2, the second material tank 3, and the third material tank 13 are all connected to each mixing head 1, and the flow direction is controlled by the third reversing valve 21, the fourth reversing valve 22, and the fifth reversing valve 23, respectively.

[0074] In this embodiment, during specific operation: if a polyurethane principle system is adopted, then the first material tank 2 is an isocyanate tank, the second material tank 3 is a combined polyether tank, and the third material tank 13 is not used; if an epoxy resin principle system is adopted, then the first material tank 2 is an epoxy resin tank, the second material tank 3 is a curing agent tank, and the third material tank 13 is an internal release agent tank.

[0075] In this embodiment, the metering pump set consists of two first metering pumps 7 connected in parallel. The two first metering pumps 7 downstream of the first material tank 2 have displacements adapted to the displacements required for pumping isocyanate and epoxy resin, respectively; similarly, the two first metering pumps 7 downstream of the second material tank 3 have displacements adapted to the displacements required for pumping combined polyether and curing agent, respectively. In addition, the displacement of the second metering pump 17 is adapted to the displacement required for pumping internal release agent.

[0076] In this embodiment, the second filter group consists of two parallel second filters 9, with one used as a backup.

[0077] In this embodiment, the third directional valve 21 is located downstream of the corresponding first flow meter 10; the input end of the third directional valve 21 is connected to the output end of the corresponding first flow meter 10, and the two output ends of the third directional valve 21 are respectively connected to the first feed channels 113 of the two mixing heads 1, and a shut-off valve or other valves can be installed on the connecting pipeline. The fourth directional valve 22 and the fifth directional valve 23 are similar.

[0078] In a more preferred embodiment, the first loop channels 115 of both mixing heads 1 are connected to the fluid circulation inlet at the top of the first material tank 2, and converge and switch flow directions at the sixth directional valve 28; through the sixth directional valve 28, the first loop channel 115 of the mixing head 1 in operation is connected to the fluid circulation inlet at the top of the first material tank 2. Similarly, the second loop channels 116 of both mixing heads 1 are connected to the fluid circulation inlet at the top of the second material tank 3, and converge and switch flow directions at the seventh directional valve 29.

[0079] For the specific fluid flow direction during operation in this embodiment, please refer to [link / reference]. Figure 1 Of course, those skilled in the art should understand thatFigure 1 The diagram illustrates the flow of raw materials in the first tank 2 and the second tank 3 under a self-circulating state; when the casting operation is performed, the raw materials are mixed in the mixing head 1 and injected into the mold.

[0080] In a more preferred embodiment, both the first tank 2 and the second tank 3 are equipped with a temperature control mechanism for regulating the temperature inside the tank.

[0081] Example 2:

[0082] An HP-RTM dispensing machine suitable for a dual-raw material system of polyurethane and epoxy resin, based on Example 1, such as... Figure 1 and Figure 2 As shown, both the first material tank 2 and the second material tank 3 are equipped with degassing mechanisms;

[0083] The degassing mechanism includes a negative pressure extraction device 24, a stirring device 25, and several degassing umbrella groups arranged vertically.

[0084] The debubbling umbrella assembly includes an upper guide plate 26 and a lower guide plate 27 that are coaxially distributed vertically. The upper guide plate 26 gradually slopes downward from the inside to the outside in the radial direction, and the lower guide plate 27 gradually slopes downward from the outside to the inside in the radial direction. The bottom outer diameter of the upper guide plate 26 is smaller than the top outer diameter of the corresponding lower guide plate 27. The bottom end of the lower guide plate 27 is provided with a flow channel.

[0085] It should be noted that, Figure 2 This diagram illustrates the structure of the degassing mechanism inside the first or second material tank. Figure 2 The CCP showcased four debubbling umbrella groups, with a bottom guide plate, whose outer diameter is slightly smaller than the inner diameter of the tank, located below the bottom debubbling umbrella group.

[0086] In a more preferred embodiment, the stirring device 25 includes a stirring shaft, and the degassing umbrella assembly is sleeved on the stirring shaft. After passing through the degassing umbrella assembly, the raw material enters the bottom area of ​​the corresponding material tank and is stirred by the stirring device. Under high-speed stirring, the air bubbles in the raw material can be quickly removed, which has a significant enhancing effect on the negative pressure degassing process of this application. Specifically, both the upper guide plate 26 and the lower guide plate 27 can be fixedly or rotatably connected to the stirring shaft. The flow channel is the gap between the lower guide plate 27 and the stirring shaft.

[0087] The upper guide plate 26 and the lower guide plate 27 can be conical or arc-shaped. For either the first material tank 2 or the second material tank 3, the fluid circulation inlet at its top is located above the uppermost debubbling umbrella group.

[0088] Example 3:

[0089] An HP-RTM dispensing machine suitable for a dual-raw material system of polyurethane and epoxy resin, based on Example 1 or 2, uses a mixing head as follows: Figure 3 and Figure 4 As shown, the device includes a nozzle 105, a piston cylinder 101, and a piston 102 located within the piston cylinder 101. The piston 102 divides the interior of the piston cylinder 101 into a first cavity 103 located near the nozzle 105 and a second cavity 104 located away from the nozzle 105. The mixing head also includes a channel 106 disposed inside the piston cylinder 101, with both ends of the channel 106 communicating with the first cavity 103 and the second cavity 104, respectively. Figure 4 The image shows the state of piston 102 when it is at the left end of its stroke.

[0090] The piston cylinder 101 is provided with a first fluid inlet / outlet 107 and a second fluid inlet / outlet 108 that communicate with the first cavity 103 and the second cavity 104, respectively; the diameter of the channel 106 is smaller than the diameter of the first fluid inlet / outlet 107 and the second fluid inlet / outlet 108.

[0091] In this embodiment, the channel 106 is C-shaped or U-shaped, and the axis of the main body of the channel 106 is parallel to the direction of movement of the piston 102.

[0092] Preferably, the inner diameter of channel 106 is 1~8mm.

[0093] Example 4:

[0094] Based on Example 3, such as Figure 4 and Figure 5 As shown, the mixing head of this embodiment also includes a throttling element 109 for throttling the channel 106 and an adjustment mechanism for controlling the throttling element 109.

[0095] The channel 106 includes at least one corner, and the throttling element 109 is partially located at one corner. Figure 4 The diagram shows the state when the throttling element 109 is at the leftmost end of its stroke, completely blocking the channel 106.

[0096] The throttling element 109 includes a throttling section 1091, a sealing section 1092, and an adjusting section 1093 arranged in sequence.

[0097] The throttling section 1091 is located at the corner and is tapered. The outer diameter of the tapered section gradually decreases from the end near the sealing section 1092 to the end away from the sealing section 1092. The outer diameter of the tapered section near the sealing section 1092 is larger than the inner diameter of the channel 106, and the outer diameter of the tapered section away from the sealing section 1092 is smaller than the inner diameter of the channel 106.

[0098] The sealing part 1092 is dynamically sealed to the piston cylinder 101, such as by providing a sealing ring;

[0099] The adjusting part 1093 is threadedly engaged with the piston cylinder 101.

[0100] In this embodiment, both the sealing part 1092 and the adjusting part 1093 are columnar; the outer wall of the adjusting part 1093 is provided with external threads, and the surface of the piston cylinder 101 is provided with a mounting hole 110 for installing the throttling element 109, and the inner wall of the mounting hole 110 is provided with an internal thread that matches the external threads.

[0101] In this embodiment, the throttling part 1091, the sealing part 1092, and the adjusting part 1093 are integrally formed.

[0102] In this embodiment, the corner is a right angle, and the axis of the throttling section 1091 is collinear with the axis of the channel 106 on either side of the right angle.

[0103] In this embodiment, the adjusting mechanism includes an adjusting nut 111 fixedly connected to the adjusting part 1093. Preferably, the adjusting part 1093 is integrally formed with the adjusting mechanism, such as by using an internal hexagon head screw.

[0104] During the operation of the mixing head in this embodiment, Figure 4 Let's take an example to illustrate: Figure 4 When the piston is at the leftmost end of its stroke, the mixing head is in a self-circulating state. When it is necessary to fully return the hydraulic oil, simply control the throttle element 109 to move to the right and open the channel 106 through the adjustment mechanism, and then inject hydraulic oil into the second cavity 104 from the second fluid inlet and outlet 108. At this time, the injected hydraulic oil enters the first cavity 103 through the channel 106, and then returns to the hydraulic station from the first fluid inlet and outlet 107 to achieve full circulation.

[0105] Example 5:

[0106] Based on Example 3 or 4, such as Figure 6 As shown, in the mixing head of this embodiment, the piston 102 includes a protrusion 1021 that dynamically seals with the inner wall of the piston cylinder 101; the piston 102 has notches on both sides of the protrusion 1021 along the axial direction. Figure 6 As shown, when piston 102 moves to Figure 4 When the piston 102 moves to the left end of its stroke, the left end of the channel 106 is connected to the notch on the left side of the protrusion 1021; conversely, when the piston 102 moves to the right end of its stroke, the right end of the channel 106 is connected to the notch on the right side of the protrusion 1021.

[0107] In this embodiment, a sealing ring is provided between the protrusion 1021 and the inner wall of the piston cylinder 101.

[0108] In addition, such as Figure 3 As shown, in this embodiment, a negative pressure sensor 112 is also provided on the end face of the nozzle 105, and the negative pressure sensor 112 is embedded in the end face of the nozzle 105.

[0109] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0110] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Additionally, the term "connection" as used herein, unless otherwise specified, can refer to a direct connection or an indirect connection via other components.

Claims

1. An HP-RTM dispensing machine suitable for a dual-raw material system of polyurethane and epoxy resin, comprising a first material tank (2), a second material tank (3), and a mixing head (1), wherein the mixing head (1) comprises a first feeding channel (113), a second feeding channel (114), a first loop channel (115), and a second loop channel (116); the output end and input end of the first material tank (2) are respectively connected to the first feeding channel (113) and the first loop channel (115), and the output end and input end of the second material tank (3) are respectively connected to the second feeding channel (114) and the second loop channel (116); characterized in that, Between the output end of the first material tank (2) and the first feed channel (113), and between the output end of the second material tank (3) and the second feed channel (114), there are a first booster pump (4), a first filter (5), a first pressure sensor (6), a metering pump group, a second pressure sensor (8), a second filter group and a first flow meter (10) connected in sequence. The metering pump group includes at least two first metering pumps (7) connected in parallel, and the displacement of any two first metering pumps (7) is different; The second filter group includes at least two second filters connected in parallel (9); The mixing head (1) includes a nozzle (105), a piston cylinder (101), and a piston (102) located inside the piston cylinder (101). The piston (102) divides the interior of the piston cylinder (101) into a first cavity (103) in the direction close to the nozzle (105) and a second cavity (104) in the direction away from the nozzle (105). It also includes a channel (106) disposed inside the piston cylinder (101), the two ends of the channel (106) being connected to the first cavity (103) and the second cavity (104) respectively; the piston cylinder (101) is provided with a first fluid inlet / outlet (107) and a second fluid inlet / outlet (108) communicating with the first cavity (103) and the second cavity (104) respectively; the diameter of the channel (106) is smaller than the diameter of the first fluid inlet / outlet (107) and the second fluid inlet / outlet (108); The mixing head (1) also includes a throttling element (109) for throttling the channel (106) and an adjustment mechanism for adjusting the throttling element (109); The channel (106) includes at least one corner, and the throttling element (109) is partially located at one corner; The throttling element (109) includes a throttling section (1091), a sealing section (1092), and an adjusting section (1093) arranged in sequence. The throttling section (1091) is located at the corner and is tapered. The outer diameter of the tapered section gradually decreases from the end near the sealing section (1092) to the end away from the sealing section (1092). The outer diameter of the tapered section near the sealing section (1092) is larger than the inner diameter of the channel (106), and the outer diameter of the tapered section away from the sealing section (1092) is smaller than the inner diameter of the channel (106). The sealing part (1092) is dynamically sealed to the piston cylinder (101); The adjusting part (1093) is threadedly engaged with the piston cylinder (101).

2. The HP-RTM dispensing machine for a dual-raw material system of polyurethane and epoxy resin according to claim 1, characterized in that, The upstream and downstream ends of the metering pump group are both controlled by the first reversing valve (11); the upstream and downstream ends of the second filter group are both controlled by the second reversing valve (12).

3. The HP-RTM dispensing machine for a dual-raw material system of polyurethane and epoxy resin according to claim 1, characterized in that, It also includes a third material tank (13), and between the output end of the third material tank (13) and the first feed channel (113), there are a second booster pump (14), a third filter (15), a third pressure sensor (16), a second metering pump (17), a fourth pressure sensor (18), a fourth filter (19), and a second flow meter (20) connected in sequence.

4. The HP-RTM dispensing machine for a dual-raw material system of polyurethane and epoxy resin according to claim 3, characterized in that, There are at least two mixing heads (1); the first material tank (2), the second material tank (3), and the third material tank (13) are all connected to each mixing head (1), and the flow direction is controlled by the third reversing valve (21), the fourth reversing valve (22), and the fifth reversing valve (23), respectively.

5. The HP-RTM dispensing machine for a dual-raw material system of polyurethane and epoxy resin according to claim 1, characterized in that, Both the first material tank (2) and the second material tank (3) are equipped with degassing mechanisms; The defoaming mechanism includes a negative pressure extraction device (24), a stirring device (25), and several defoaming umbrella groups arranged vertically. The debubbling umbrella assembly includes an upper guide plate (26) and a lower guide plate (27) that are coaxial and distributed vertically. The upper guide plate (26) gradually slopes downward from the inside to the outside in the radial direction, and the lower guide plate (27) gradually slopes downward from the outside to the inside in the radial direction. The bottom outer diameter of the upper guide plate (26) is smaller than the top outer diameter of the corresponding lower guide plate (27). The bottom end of the lower guide plate (27) is provided with a flow channel.

6. The HP-RTM dispensing machine for a dual-raw material system of polyurethane and epoxy resin according to claim 1, characterized in that, The sealing part (1092) and the adjusting part (1093) are both columnar; the outer wall of the adjusting part (1093) is provided with external threads, and the surface of the piston cylinder (101) is provided with a mounting hole (110) for installing the throttling element (109), and the inner wall of the mounting hole (110) is provided with an internal thread that matches the external thread.

7. The HP-RTM dispensing machine for a dual-raw material system of polyurethane and epoxy resin according to claim 1, characterized in that, The piston (102) includes a protrusion (1021) that dynamically seals with the inner wall of the piston cylinder (101); the piston (102) has notches on both sides of the protrusion (1021) along the axial direction.

8. The HP-RTM dispensing machine for a dual-raw material system of polyurethane and epoxy resin according to claim 1, characterized in that, A negative pressure sensor (112) is provided on the end face of the nozzle (105).

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