Composite material curing forming system

Abstract

The invention relates to a composite material curing forming system, belongs to the technical field of material forming, and solves the problem of low heat exchange efficiency in the thermal forming process of a large composite material workpiece in the prior art. The device comprises a cabin body, a cabin door, a cabin tail sealing plate, an inner partition plate, a fan and a heating device. The cabin body is cylindrical, the cabin door is arranged at the front end of the cabin body, and the inner surface of the cabin door is a spherical concave surface; the cabin tail sealing plate is arranged at the tail end of the cabin body, the inner partition plate is a cylindrical body and is arranged in the cabin body, and the central axis of the inner partition plate coincides with the central axis of the cabin body; and the fan and the heating device are arranged on the cabin tail sealing plate. The outer airflow channel is formed between the cabin body and the inner partition plate, the inner airflow channel is formed in the inner partition plate, and the fan and the heating device are arranged at the cabin tail sealing plate, so that circulating airflow is formed in the whole system, the airflow is heated through the heating device, and then the composite material is heated through the airflow; the temperature rise of the composite material is realized.

Description

Technical Field

[0001] The invention relates to the technical field of material molding, and in particular to a composite material curing molding system. Background Art

[0002] The working principle of the composite material curing and molding system is to heat and pressurize the composite material blank, honeycomb sandwich structure or adhesive structure in the composite material curing and molding system through the process of heating, pressurizing, heat preservation (medium temperature or high temperature), pressure maintenance, cooling and pressure relief to become a product with the required shape and quality state.

[0003] As the effective diameter and length of the composite material curing molding system continue to expand, the uneven temperature distribution of the product during the curing process becomes increasingly severe. In the composite material curing molding system, a sudden expansion jet is formed at the outlet of the external air flow channel. Since the hatch is a spherical concave surface, the sudden expansion jet converges 180 degrees after passing through the hatch and flows to the inlet of the internal air flow channel, resulting in a high flow velocity in the middle and a low flow velocity around, which is very unfavorable for the heat exchange of the cylindrical workpiece and affects the efficiency of heating the workpiece.

[0004] In addition, as the size of composite material curing molding system and product increases, the heat transfer effect along the length direction gradually decreases, which not only affects the final quality of the product, but also reduces the curing efficiency. my country's solutions for temperature uniformity in the curing engineering of composite material curing molding system are still insufficient.

[0005] At present, with the increase in the effective size and length of the composite material curing molding system, the measures to improve the temperature uniformity of the product mainly rely on extending the insulation time and controlling the heating rate. However, such control methods will not only extend the curing process time, making the production process more time-consuming, but also reduce energy efficiency. Therefore, we need more innovative strategies and technical means to effectively deal with the problems caused by temperature uniformity. Summary of the invention

[0006] In view of the above analysis, an embodiment of the present invention aims to provide a composite material curing and forming system to solve the problem of uneven temperature during the hot forming process of a large composite material workpiece.

[0007] On the one hand, the present invention provides a composite material curing and molding system, including a cabin, a cabin door, a stern cover plate, an inner partition, a fan and a heating device; the cabin is cylindrical, the cabin door is arranged at the front end of the cabin, and the inner surface of the cabin door is a spherical concave surface; the stern cover plate is arranged at the rear end of the cabin, the inner partition is a cylindrical body, the inner partition is arranged inside the cabin, and the central axis of the inner partition coincides with the central axis of the cabin; the fan and the heating device are arranged on the stern cover plate.

[0008] Furthermore, it also includes a porous flow equalizing plate, and the porous flow equalizing plate is arranged between the cabin body and the cabin door.

[0009] Furthermore, the porous flow equalizing plate is a circular plate, and its diameter is equal to the inner diameter of the cabin.

[0010] Furthermore, the porous flow balancing plate is provided with a plurality of flow balancing holes, and the plurality of flow balancing holes are unevenly distributed.

[0011] Furthermore, the diameters of the multiple flow equalizing holes are all equal.

[0012] Furthermore, the plurality of flow balancing holes are distributed in a manner of being dense in the peripheral area and sparse in the central area.

[0013] Furthermore, the density of the plurality of flow balancing holes in the peripheral area is two to three times the density in the central area.

[0014] Furthermore, the central area is a square area centered on the center of the porous flow equalizing plate.

[0015] Furthermore, the side length of the square area is less than or equal to the radius of the inner partition.

[0016] Furthermore, the multiple flow balancing holes are evenly distributed.

[0017] On the other hand, the present invention also relates to a composite material curing and molding method, which is implemented using the composite material curing and molding system described above.

[0018] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0019] (1) The composite material curing and molding system of the present invention forms an external airflow channel between the cabin body and the inner partition, forms an internal airflow channel inside the inner partition, and arranges a fan and a heating device at the cabin tail sealing plate to form a circulating airflow inside the entire system. The airflow is heated by the heating device, and the composite material is then heated by the airflow, thereby achieving heating of the composite material.

[0020] (2) The composite material curing and molding system of the present invention can disperse the fluid with uneven flow rate by setting a porous flow equalizing plate between the cabin door and the inner partition, change the flow rate distribution of the fluid in the inner air flow channel, and thus improve the heating efficiency of the cylindrical workpiece.

[0021] (3) The composite material curing and molding system of the present invention divides the heated airflow into two parts by providing a baffle and a drainage port. One part is forwardly collected to the hatch area along the outer airflow channel, and then enters the inner airflow channel through the inlet and moves toward the rear end, thereby realizing heat exchange with the product in the inner airflow channel; the other part enters the drainage port area and then enters the rear half of the inner airflow channel through the drainage port, thereby realizing heat exchange with the product in this area, thereby reducing the unevenness of the product temperature.

[0022] In the present invention, the above-mentioned technical solutions can also be combined with each other to achieve more preferred combination solutions. Other features and advantages of the present invention will be described in the subsequent description, and some advantages can become obvious from the description, or can be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained through the contents particularly pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The drawings are only for the purpose of illustrating particular embodiments and are not to be considered limiting of the present invention. Like reference symbols denote like components throughout the drawings.

[0024] Figure 1 This is a schematic diagram of the structure of the composite material curing and molding system after removing half of the cabin;

[0025] Figure 2 for Figure 1 Schematic diagram of the local structure from the K-direction perspective;

[0026] Figure 3 for Figure 1 AA section view in the figure;

[0027] Figure 4 This is a schematic diagram of the position of the composite material in the curing molding system when the product is slender;

[0028] Figure 5 This is a schematic diagram of the position of the composite material in the curing molding system when the product is cylindrical;

[0029] Figure 6 A schematic diagram of the position of the composite material in the curing molding system when the product is a multi-layered elongated product (partially enlarged view);

[0030] Figure 7 It is a structural schematic diagram of a first embodiment of a porous flow equalizing plate;

[0031] Figure 8 It is a structural schematic diagram of a second embodiment of a porous flow equalizing plate;

[0032] Fig. 9 It is a structural schematic diagram of the third embodiment of the porous flow equalizing plate.

[0033] Reference numerals:

[0034] 11-first fan; 12-second fan; 2-heating device; 3-stern cover plate; 4-cabin body; 5-inner partition; 6-cabin door; 7-baffle; 8-drainage port; 9-multi-porous flow equalizing plate; 10-slender product; 13-cylindrical product; 14-temperature sensor. DETAILED DESCRIPTION

[0035] The preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not used to limit the scope of the present invention.

[0036] Example 1

[0037] A specific embodiment of the present invention, as Figure 1-Figure 5 As shown, a composite material curing and molding system is disclosed. The main body of the composite material curing and molding system is cylindrical, and both ends are spherical.

[0038] See also Figure 1 The composite material curing and molding system includes a cabin door 6 arranged at the front end of the cabin body 4, the cabin body 4 constituting the outer wall of the composite material curing and molding system, an inner partition 5 arranged inside the cabin body 4, and a cabin tail sealing plate 3 arranged at the tail of the composite material curing and molding system, and also includes a first fan 11, a second fan 12 and a heating device 2 arranged on the cabin tail sealing plate 3.

[0039] The raw materials forming the product enter the mold cavity inside the inner partition 5 from the tank door of the composite material curing molding system and are hot-pressed. Figure 4-Figure 6 shown.

[0040] An external airflow channel is formed between the cabin 4 and the inner partition 5, and an internal airflow channel is formed inside the inner partition 5. The gas is extracted from the rear end of the inner partition 5 by the first fan 11 and the second fan 12, and is sent to the external airflow channel between the cabin 4 and the inner partition 5 after being heated by the heating device 2. The airflow moves toward the cabin door 6 along the external airflow channel, enters the internal airflow channel after being collected by the cabin door 6, and moves toward the rear end of the inner partition 5, completing the airflow circulation inside the entire composite material curing and molding system, and then heating the composite material through heat exchange during the airflow circulation process.

[0041] The cabin body 4 is cylindrical and has a circular cross section. Figure 3As shown. The inner baffle 5 is cylindrical and coaxial with the cabin 4, and the diameter of the inner baffle 5 is between 9 / 10 and 19 / 20 of the diameter of the cabin 4. With such a configuration, the inner baffle 5 has a large enough space inside to accommodate composite materials and product molds, etc., and there is enough space between the inner baffle 5 and the cabin 4 to form an external gas flow channel for the fluid to move from the tail of the cabin 4 to the position of the hatch 6.

[0042] In a preferred embodiment, a plurality of drainage ports 8 are provided at the top and bottom of the inner partition 5, such as Figure 1-Figure 3 As shown. The drainage port 8 can connect the external airflow channel and the internal airflow channel. That is, the airflow entering the area can enter the internal airflow channel through the drainage port 8. The drainage port 8 is provided with a control device, and the state of the drainage port 8 can be adjusted by the control device, thereby controlling the flow rate of the fluid flowing from the drainage port 8 to the internal airflow channel.

[0043] See also Figure 1-Figure 2 The air inlet 8 is only arranged in the rear half of the composite material curing and molding system, that is, the area near the tail. With this arrangement, the heated airflow with a higher temperature can enter the rear half of the inner partition 5 and directly heat the rear half of the composite material, thereby avoiding the problem of low temperature of the composite material at the rear end of the cabin 4 due to the gradual cooling of the airflow when it flows from the cabin door 6 to the rear end of the cabin 4.

[0044] The drainage ports 8 may be square holes or circular holes, and are evenly arranged at the top and bottom of the inner partition 5. Three to five drainage ports 8 may be arranged side by side in the direction of the cross section of the inner partition 5, preferably four. Each drainage port 8 is provided with a position number, so that the control device can control the state of each drainage port 8 individually.

[0045] The drainage port 8 includes a through hole provided on the inner partition 5, and a control unit provided on each through hole. The control unit may be a one-way electromagnetic valve, a flow valve, or a baffle that can be driven to move laterally or longitudinally independently. The control unit may control the drainage port 8 to be opened or closed, and may also control the size of the opening of the drainage port 8.

[0046] In addition, when multiple layers of composite materials are arranged in the inner partition 5 to form a multi-layer product, the upper drainage port 8 gives priority to improving the heat exchange of the composite materials in the top layer, and the lower drainage port 8 gives priority to improving the heat exchange of the composite materials in the bottom layer, and the composite materials in the middle are still difficult to be improved. In order to solve this problem, a row of auxiliary drainage ports are respectively arranged in the middle of both sides of the inner partition 5. The auxiliary drainage ports can introduce heated gas from the middle to the inside of the inner partition 5. Such an arrangement is suitable for the situation where multiple layers of composite materials are arranged in the inner partition 5, and can assist in improving the heat exchange of the composite materials in the middle layer.

[0047] Furthermore, the inner baffle 5 includes arc surfaces at both sides and horizontal surfaces at the top and bottom, and the drainage port 8 is respectively arranged in the horizontal planes at the top and bottom of the inner baffle 5. Such an arrangement can reduce the difficulty of construction on the one hand, and on the other hand, can make the cross-sectional area of ​​the region where the drainage port 8 is located account for a larger proportion of the cross-sectional area of ​​the entire external air flow channel. Under the condition of the same flow rate, the flow rate proportion allocated to the region where the drainage port 8 is located becomes larger, which will enhance the heat exchange in the middle and rear sections.

[0048] In order to further increase the amount of airflow entering the guide port 8, a baffle 7 is provided between the inner partition 5 and the cabin 4, as shown in FIG1- Figure 3 As shown. The baffle 7 includes three flat plates, two of which extend from the rear end of the cabin 4 along the central axis of the composite material curing and molding system, and the other flat plate is perpendicular to the two flat plates and fixedly connected to the ends of the two flat plates. In the vertical direction, one end of the baffle 7 is connected to the cabin 4, and the other end is connected to the horizontal surface of the top or bottom of the inner partition 5. The baffle 7 encloses the area where the drainage port 8 is set, and the baffle 7 blocks the airflow entering the area, so that it cannot continue to move toward the direction of the cabin door 6.

[0049] Furthermore, the baffle 7 is composed of two flat plates and one arc plate, wherein the two flat plates extend along the central axis of the composite material curing molding system, and the arc plate is located near the middle of the cabin 4, connected to the ends of the two flat plates and smoothly transitioned. Compared with the solution with three flat plates, the end of this baffle 7 is rounded, so that the airflow flows more smoothly when passing through this position, avoiding turbulence that causes the airflow velocity to decrease, thereby affecting the heat exchange efficiency.

[0050] The area between the baffle plate 7, the cabin body 4 and the inner partition plate 5 forms a drainage port area. Figure 3 After the airflow is heated, a part of it enters the drainage port area and then enters the inner airflow channel through the drainage port 8, and the other part is gathered from the outer airflow channel area to the hatch 6 area, and after passing through the hatch 6, it is gathered 180 degrees and then enters the inner airflow channel through the entrance and moves toward the tail end.

[0051] With this arrangement, air is supplied to the middle and rear areas inside the inner partition 5 through the multiple outlets 8 in the two independent outlet areas of the external air flow channel, thereby improving the heat exchange of the product in this area, ensuring that heat can be evenly and efficiently transferred to every corner, and reducing uneven product temperature.

[0052] In a preferred solution, temperature sensors 14 may also be provided in different areas of the product, such as Figure 4 , Figure 5 , Figure 6During the curing process, the size of the drainage port 8 can be adjusted according to the product temperature monitored by the temperature sensor 14, so that air supply and heat supplement measures can be performed more accurately to solve the problem of uneven product temperature.

[0053] Furthermore, due to the sudden expansion jet formed at the outlet of the external air flow channel, after passing through the hatch 6, it converges 180 degrees to flow toward the inlet of the internal air flow channel, resulting in a high flow velocity in the middle and a low flow velocity around. In order to solve this problem, a porous flow plate 9 is set at the outlet of the external air flow channel, such as Figure 1 , Figure 5 shown.

[0054] The structure of the first porous flow plate 9 is as follows Figure 7 As shown. The diameter of the porous flow balancing plate 9 is equal to the inner diameter of the cabin 4. A plurality of flow balancing holes are distributed on the porous flow balancing plate 9. The diameters of the plurality of flow balancing holes are equal, and the distribution of the flow balancing holes is dense in the periphery and sparse in the middle. Specifically, the density of the plurality of flow balancing holes in the peripheral area is two to three times the density of the central area. The central area is a square area centered on the center of the porous flow balancing plate, and the side length of the square area is less than or equal to the radius of the inner partition.

[0055] After passing through the first porous flow plate 9, the fluid with uneven flow velocity can be dispersed, so that the flow velocity of the fluid in the inner air flow channel is small in the middle and large around, which is beneficial to improve the heat exchange efficiency of the cylindrical workpiece. Figure 5 shown.

[0056] The structure of the second porous flow plate 9 is as follows Figure 8 As shown, the structure of the third porous flow plate 9 is as follows Fig. 9 The flow balancing holes in the two types of porous flow balancing plates 9 are of the same size and are evenly distributed on the entire porous flow balancing plate 9. Among them, the flow balancing holes of the second type of porous flow balancing plate 9 are circular holes, and the flow balancing holes of the third type of porous flow balancing plate 9 are square holes.

[0057] Both porous flow equalizing plates 9 can break up the fluid with uneven flow velocity, so that the flow velocity of each area of ​​the internal air flow channel is basically the same. When a flow equalizing plate with circular holes is used, the wind resistance is smaller than that when a square hole is used, and the air flow rate is larger. By setting a porous flow equalizing plate 9, the uneven temperature of the product can be further reduced.

[0058] In order to improve the versatility of the equipment, the porous flow equalizing plate 9 can be configured to be detachable.

[0059] The composite material curing and molding system of the present invention forms an external airflow channel between the cabin and the inner baffle, forms an internal airflow channel inside the inner baffle, and arranges a fan and a heating device at the cabin tail sealing plate to form a circulating airflow inside the entire system, heats the airflow through the heating device, and then heats the composite material through the airflow to achieve heating of the composite material. In addition, by arranging a multi-hole flow plate between the cabin door and the inner baffle, the fluid with uneven flow velocity can be dispersed, and the flow velocity distribution mode of the fluid in the inner airflow channel can be changed, thereby improving the heating efficiency of the cylindrical workpiece.

[0060] Example 2

[0061] This embodiment 2 involves the curing and molding steps of the composite material curing and molding system, which is implemented using the composite material curing and molding system in embodiment 1. The specific steps are as follows:

[0062] S1: Determine whether to install a porous flow equalizing plate 9 and what type of porous flow equalizing plate to install according to the product type;

[0063] S2: controlling the state of the drainage port 8 according to the shape of the product and its position in the composite material curing and molding system;

[0064] S3: Start the hot pressing process, and the composite material starts to solidify and form after heating; adjust the state of the drainage port 8 in real time according to the data fed back by the temperature sensor 14;

[0065] S4: After the composite material is cured and formed, the temperature is reduced and the pressure is released.

[0066] Before step S1 , production preparations are completed and the product mold and the composite material are placed in the working area within the inner partition 5 .

[0067] Step S1 specifically includes: if the product type is a slender type, such as a wing product component, Figure 4 As shown, since it is placed near the central axis of the inner air flow channel, the phenomenon of high flow velocity in the middle and low flow velocity around does not affect the heat exchange of the product, so there is no need to install a porous flow equalizing plate 9. At this time, the central flow velocity of the fluid entering the inner air flow channel from the outer air flow channel area is high, and after flowing through the slender product, it forms a flow guide around the plate to achieve the heating of the composite material. However, due to the continuous decrease in flow velocity along the axial direction and the continuous decrease in fluid temperature, the heat exchange efficiency continues to decrease, making the temperature of the front end of the slender product high and the temperature of the rear end low; at this time, the high-temperature fluid entering the inner air flow channel from the multiple drainage ports 8 in the drainage port area flows to the middle and rear end of the product, thereby enhancing the heat exchange in this area, thereby reducing the temperature unevenness of the slender product.

[0068] If the product type is cylindrical, such as a fuselage product component, its position is mainly near the inner partition 5, such as Figure 5As shown, the flow velocity of the traditional air flow channel shows a phenomenon that the flow velocity in the middle is high and the flow velocity around is low, which is not conducive to heating and heat preservation of the product. At this time, the first porous flow plate 9 is selected to be installed to disperse the fluid with uneven flow velocity, increase the fluid flow velocity around the inner partition 5, and thus enhance the heat exchange capacity of the product.

[0069] If multiple layers of elongated products are built in the inner partition 5, such as double or triple wings, Figure 6 As shown, the second or third porous flow equalizing plate 9 is selected to be installed to disperse the fluid with uneven flow velocity so that the flow velocity of the fluid in each area of ​​the inner air flow channel is basically consistent to reduce the temperature unevenness.

[0070] In step S2, a preferred method is to control the drainage port 8 facing the product to be opened, and the other drainage ports 8 to be closed.

[0071] For example, if the product is a wing, the air inlet 8 facing the wing is controlled to be open, and the air inlet 8 in the rest of the area is closed. Since the air volume entering the air inlet area is certain (determined only by the inlet size of the air inlet area and the fan output power), closing some air inlet 8 can increase the speed of the air inlet 8 in the rest of the area, thereby increasing the wind speed blowing toward the product, increasing the convective heat transfer coefficient on the product surface, thereby improving heat exchange and further reducing the temperature difference of the product.

[0072] In step S3, after the hot pressing process is started, the composite material will gradually solidify and take shape. During this process, the data fed back by the temperature sensor 14 is monitored in real time and processed according to the control program. If the temperature of the product is found to be uneven and the temperature difference is greater than or equal to ±5°, the drainage port 8 of the corresponding area is controlled to be opened or closed.

[0073] At the same time, the temperature sensor device 14 monitors the temperature of the product in real time to adjust the size of the drainage port 8 to control the flow rate of the air outlet.

[0074] The present invention provides a composite material curing and molding system, which can adjust the air flow channel according to different types of products and can effectively improve the curing effect of large composite material components.

[0075] For large wing product components, the porous flow equalizing plate 9 is removed, and the state of the drainage port 8 is adjusted in real time according to the condition of the temperature sensor 14, thereby solving the problem of uneven product temperature.

[0076] For large fuselage product components, a multi-hole flow equalizing plate 9 is added, and the drainage port is closed or the size of the drainage port 8 is reduced according to the condition of the temperature sensor 14, thereby improving the heat exchange efficiency of the product.

[0077] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A composite material curing and molding system, characterized in that: It includes a cabin, a cabin door, a stern cover plate, an inner partition, a fan and a heating device; the cabin is cylindrical, the cabin door is arranged at the front end of the cabin, and the inner surface of the cabin door is a spherical concave surface; the stern cover plate is arranged at the rear end of the cabin, the inner partition is a cylindrical body, the inner partition is arranged inside the cabin, and the central axis of the inner partition coincides with the central axis of the cabin; the fan and the heating device are arranged on the stern cover plate.

2. The composite material curing and molding system according to claim 1, characterized in that: It also includes a porous flow equalizing plate, which is arranged between the cabin body and the cabin door.

3. The composite material curing and molding system according to claim 2, characterized in that: The porous flow balancing plate is a circular plate, and its diameter is equal to the inner diameter of the cabin.

4. The composite material curing and molding system according to claim 3, characterized in that: The multi-porous flow balancing plate is provided with a plurality of flow balancing holes, and the plurality of flow balancing holes are non-uniformly distributed.

5. The composite material curing and molding system according to claim 4, characterized in that: The diameters of the multiple flow-balancing holes are all equal.

6. The composite material curing and molding system according to claim 4, characterized in that: The distribution of the multiple flow balancing holes is dense in the peripheral area and sparse in the central area.

7. The composite material curing and molding system according to claim 6, characterized in that: The density of the multiple flow balancing holes in the peripheral area is two to three times that of the central area.

8. The composite material curing and molding system according to claim 6 or 7, characterized in that: The central area is a square area centered on the center of the porous flow equalizing plate.

9. The composite material curing and molding system according to claim 8, characterized in that: The side length of the square area is less than or equal to the radius of the inner partition.

10. A method for curing and molding a composite material, characterized in that: The method is implemented by using a composite material curing and molding system according to any one of claims 1 to 9.

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