Multi-cavity injection infusion molding apparatus and process

Abstract

The present application relates to a kind of multi-cavity injection infiltration forming device and process, including guide plate, infiltration mold, forming mold and glue pipe, guide plate, infiltration mold, forming mold are sequentially arranged, infiltration mold has multiple infiltration cavities, infiltration cavity extends from one end of infiltration mold to the other end, and forms entrance at one end of infiltration mold, forms outlet at the other end;Glue pipe is provided with multiple, multiple glue pipe is inserted from the entrance of infiltration cavity;Forming mold has forming cavity, the cross-sectional shape of forming cavity is identical with the cross-sectional shape of product to be formed, forming cavity extends from one end of forming mold to the other end, and forms entrance at one end of forming mold, forms outlet at the other end, the entrance of forming cavity is connected with the outlet of infiltration cavity and is communicated.The present application reduces the volatilization of resin, environmental pollution, ensures the uniform distribution of yarn, ensures its performance stability;Can reach ideal infiltration effect, guarantee yield.

Description

Technical Field

[0001] This invention belongs to the field of composite material molding technology, specifically relating to a multi-cavity injection impregnation molding device and process. Background Technology

[0002] Pultrusion molding of composite materials is a process that produces composite materials by impregnating continuous fibers or fabrics with resin under the traction of traction equipment and curing the resin by heating the molding die. It has the advantages of simple process, high degree of automation, continuous production capability, high fiber content and high mechanical strength, and is widely used in wind power, photovoltaic, aerospace and other fields.

[0003] Traditional pultrusion processes typically employ open resin baths for impregnation. The yarn is impregnated with resin in the bath, excess resin is squeezed out by pressure rollers, and then the yarn enters a mold for curing. However, for some highly volatile or photosensitive resins, open resin baths cannot achieve continuous production. To overcome this challenge, injection impregnation methods have emerged.

[0004] See the patent with publication number CN106515047A, which describes a reaction injection pultrusion molding equipment and method. It uses an injection gun connected to a glue injection device to directly inject resin into a closed mold. The glue injection device sets the injection port in the direction perpendicular to the mold and applies a certain injection pressure, which solves the problem of resin volatility or exposure to light. However, this glue injection method has poor wetting effect and is greatly affected by the injection pressure. Impregnation defects are prone to appear on the surface of the sheet, affecting its appearance and mechanical properties, and the yield cannot be guaranteed. At the same time, the slow wetting speed leads to slow pultrusion speed and low production efficiency. Summary of the Invention

[0005] One object of the present invention is to provide a multi-cavity injection impregnation molding apparatus.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A multi-cavity injection molding apparatus includes a yarn guide plate, an impregnation mold, a molding mold, and an injection tube, wherein the yarn guide plate, the impregnation mold, and the molding mold are arranged sequentially.

[0008] The impregnation mold has multiple impregnation cavities, which extend from one end of the impregnation mold to the other end, with an inlet at one end and an outlet at the other end.

[0009] Multiple glue injection tubes are provided, and multiple glue injection tubes are inserted from the inlet of the impregnation chamber;

[0010] The molding die has a molding cavity with the same cross-sectional shape as the product to be molded. The molding cavity extends from one end of the molding die to the other end, with an inlet at one end and an outlet at the other end. The inlet of the molding cavity is connected to and communicates with the outlet of the impregnation cavity.

[0011] Preferably, in the above technical solution, the multiple impregnation cavities of the impregnation mold are independent of each other, and the cross-sectional shape of each impregnation cavity is the same as the cross-sectional shape of the product to be molded.

[0012] More preferably, the impregnation chamber includes a first impregnation chamber and a second impregnation chamber, which are arranged vertically. The first impregnation chamber extends from its inlet to its outlet at an angle from top to bottom, and the second impregnation chamber extends from its inlet to its outlet at an angle from bottom to top.

[0013] More preferably, the cross-sectional shape of the impregnation cavity and the forming cavity is both straight.

[0014] Preferably, in the above technical solution, the multiple impregnation cavities of the impregnation mold are interconnected and enclosed in the same shape as the product to be formed.

[0015] More preferably, the cross-sectional area of ​​the impregnation cavity decreases proportionally from its inlet to its outlet.

[0016] More preferably, the cross-sectional shapes of the impregnation cavity and the molding cavity are both annular, and the cross-sectional shapes and sizes of the outlet of the impregnation cavity and the inlet of the molding cavity are the same.

[0017] Preferably, in the above technical solution, the yarn guide plate is provided with a plurality of yarn guide holes and glue injection tube holes, the glue injection tube holes are distributed among the yarn guide holes, and the glue injection tube is fixed in the glue injection tube holes.

[0018] Preferably, in the above-mentioned technical solution, each of the impregnation cavities is uniformly provided with multiple glue injection tubes.

[0019] Another object of the present invention is to provide a multi-cavity injection dip molding process.

[0020] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0021] A multi-cavity injection impregnation molding process is disclosed, wherein the process employs the aforementioned multi-cavity injection impregnation molding device, and the impregnation medium is injected through the injection tube from the inlet of the impregnation cavity, wherein the flow direction of the injected impregnation medium is consistent with the direction of yarn pultrusion.

[0022] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0023] The present invention adopts a closed mold. The resin is injected into the impregnation mold from the yarn inlet through the injection tube, which reduces the volatilization of resin and reduces environmental pollution. At the same time, the continuous injection of resin effectively solves the problem of "new and old glue" that exists in the traditional process of intermittently adding glue to the glue tank, and further ensures the uniform distribution of yarn and the stability of its performance.

[0024] The multi-cavity injection method of the impregnation chamber in this invention divides the yarn into several parts for separate impregnation, achieving an ideal impregnation effect, ensuring a high yield, and preventing snowflake-like whitening on the surface of the board due to poor impregnation. Attached Figure Description

[0025] Appendix Figure 1 This is a cross-sectional schematic diagram of the device in Embodiment 1;

[0026] Appendix Figure 2 This is a schematic diagram of the yarn guide plate in Example 1;

[0027] Appendix Figure 3 This is a schematic diagram of the immersion mold in Example 1;

[0028] Appendix Figure 4 This is a schematic diagram of the dispensing tube setup in Example 1;

[0029] Appendix Figure 5 This is a schematic diagram of the molding die in Example 1;

[0030] Appendix Figure 6 This is a schematic diagram of the yarn guide plate in Example 2;

[0031] Appendix Figure 7 This is a schematic diagram of the immersion mold in Example 2;

[0032] Appendix Figure 8 This is a schematic diagram of the dispensing tube setup in Example 2;

[0033] Appendix Figure 9 This is a schematic diagram of the molding die in Example 2;

[0034] Appendix Figure 10 This is a schematic diagram of resin flow in an existing injection method.

[0035] Appendix Figure 11 This is a schematic diagram of resin flow in the injection method of this embodiment.

[0036] In the attached diagrams above:

[0037] 1. Yarn guide plate; 10. Yarn guide hole; 11. Glue injection tube hole;

[0038] 2. Impregnation mold; 20. Impregnation cavity; 200. First impregnation cavity; 201. Second impregnation cavity;

[0039] 3. Molding mold; 30. Molding cavity;

[0040] 4. Injection tubing;

[0041] 5. Yarn. Detailed Implementation

[0042] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and 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. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0044] like Figure 1-9 As shown: A multi-cavity injection impregnation molding device includes a yarn guide plate 1, an impregnation mold 2, a molding mold 3, and an injection tube 4, wherein the yarn guide plate 1, the impregnation mold 2, and the molding mold 3 are arranged sequentially.

[0045] The yarn guide plate 1 has multiple yarn guide holes 10 and glue injection tube holes 11. The yarn guide plate 1 allows the yarn to be layered in an orderly manner during the introduction process, minimizing yarn tangling; the yarn guide holes 10 are evenly distributed to ensure uniform yarn distribution in the upper and lower molds, ensuring the stability of the fiber volume content and mechanical properties of the board; the glue injection tube 11 added to the yarn guide plate 1 fixes the position of the glue injection tube 4, allowing the glue injection tube 4 to be distributed between the yarn layers, so that the resin can flow along the yarn direction and also along the direction perpendicular to the yarn, further improving the wetting speed of the yarn.

[0046] The impregnation mold 2 has multiple impregnation chambers 20, which extend from one end to the other, forming an inlet at one end and an outlet at the other. The shape of the impregnation chambers 20 matches the shape of the product, such as a sheet material, or other shapes, such as square tubes or round tubes. The multiple impregnation chambers 20 can separate the yarn, further reducing yarn tangling and lint, thus improving the product's appearance. They also distribute the yarn evenly, ensuring uniform distribution and further guaranteeing product quality.

[0047] The injection tube 4 is inserted into the inlet of the impregnation chamber 20, and each impregnation chamber 20 is equipped with an injection tube 4. The injection tube 4 is inserted vertically into the impregnation chamber 20, allowing the resin to be directly injected into the impregnation chamber 20 in the thickness direction. This combination improves the wettability of the fiber reinforcement material. At the same time, each impregnation chamber 20 has multiple injection tubes 4, which are evenly distributed to ensure the uniformity of yarn distribution and guarantee product quality. The injection tubes 4 in each impregnation chamber 20 divide the yarn into several parts for separate impregnation, rather than the traditional method of injecting resin from a single point. Compared with the past, the impregnation effect of the yarn can be significantly improved, ensuring its yield. The distance that the resin needs to flow is significantly reduced, and the required time is reduced, which can correspondingly increase the pultrusion speed and improve production efficiency.

[0048] The molding die 3 has a molding cavity 30, the cross-sectional shape of which is the same as that of the product to be molded. The molding cavity 30 extends from one end of the molding die 3 to the other end, and forms an inlet at one end of the molding die 3 and an outlet at the other end. The inlet of the molding cavity 30 is connected to and communicates with the outlet of the impregnation cavity 20.

[0049] Example 1:

[0050] A multi-cavity injection impregnation molding device is mainly used for impregnating and molding sheet materials. The device includes a yarn guide plate 1, an impregnation mold 2, a molding mold 3, and an injection tube 4, wherein the yarn guide plate 1, the impregnation mold 2, and the molding mold 3 are arranged sequentially, as shown below. Figure 1 As shown. The following is a detailed description of each component:

[0051] like Figure 2 As shown: The yarn guide plate 1 has multiple yarn guide holes 10 and glue injection tube holes 11. In the figure: the yarn guide holes 10 are arranged in multiple rows in the vertical direction of the yarn guide plate 1, with multiple holes in each row; the glue injection tube holes 11 are arranged in two rows, located between the two rows of yarn guide holes 10. Of course, the glue injection tube holes 11 can also be arranged in three or four rows, distributed at intervals with the yarn guide holes 10 in the vertical direction.

[0052] The impregnation mold 2 has a first impregnation cavity 200 and a second impregnation cavity 201. The shapes of the first impregnation cavity 200 and the second impregnation cavity 201 are consistent with the shape of the sheet material, or in other words, their cross-sectional shape is straight. The first impregnation cavity 200 and the second impregnation cavity 201 are independently arranged and distributed vertically. The first impregnation cavity 200 extends from one end of the impregnation mold 2 to the other end, forming an inlet at one end and an outlet at the other end, and extends slopingly from top to bottom from its inlet to its outlet. Similarly, the second impregnation cavity 201 also extends from one end of the impregnation mold 2 to the other end, forming an inlet at one end and an outlet at the other end, but extends slopingly from bottom to top from its inlet to its outlet. Figure 1 , 3 As shown.

[0053] Multiple injection tubes 4 are provided, and each injection tube 4 is fixed in the injection tube hole 11 of the yarn guide plate 1. They are inserted into the inlets of the first impregnation chamber 200 and the second impregnation chamber 201. In the diagram, three injection tubes 4 are inserted into each of the first and second impregnation chambers 201, and they are evenly distributed. The injection tubes 4 are inserted vertically into the first and second impregnation chambers 201. Figure 4 As shown.

[0054] The molding die 3 has a molding cavity 30, the shape of which is consistent with the shape of the sheet material, or in other words, its cross-sectional shape is straight. The molding cavity 30 extends from one end of the molding die 3 to the other end, forming an inlet at one end and an outlet at the other end. The inlet of the molding cavity 30 is connected and communicates with the outlets of the first impregnation cavity 200 and the second impregnation cavity 201, as shown below. Figure 1 , 5 As shown. The molding die 3 can be heated to solidify the impregnated yarn, reducing the cost of pultrusion molding.

[0055] During impregnation: the yarn 5 passes through the yarn guide hole 10 of the yarn guide plate 1 and is divided into two bundles, which enter the first impregnation chamber 200 and the second impregnation chamber 201 of the impregnation mold 2. The glue injection tube 4 injects resin from the inlet of the first impregnation chamber 200 and the second impregnation chamber 201 to impregnate the yarn 5. The resin in the first impregnation chamber 200 flows from top to bottom to impregnate the yarn in the first impregnation chamber 200. The resin in the second impregnation chamber 201 flows from bottom to top under the glue injection pressure to impregnate the yarn in the second impregnation chamber 201. After impregnation is completed, the glue injection tube 4 stops injecting glue. Since the second impregnation chamber 201 extends downward at an angle, both the second impregnation chamber 201 itself and the excess resin in the first impregnation chamber 200 can flow out from the second impregnation chamber 201 by its own gravity, preventing the board from having too much glue content, which would affect its mechanical properties. Furthermore, the impregnation mold 2 does not need to open a separate overflow port for glue discharge.

[0056] Example 2:

[0057] A multi-cavity injection impregnation molding device is mainly used for impregnating and molding tubing, which can be square tubing, round tubing, etc. This embodiment uses square tubing as an example for illustration. The device includes a yarn guide plate 1, an impregnation mold 2, a molding mold 3, and an injection tube 4, wherein the yarn guide plate 1, the impregnation mold 2, and the molding mold 3 are arranged sequentially. The following is a detailed description of each component:

[0058] like Figure 6 As shown: The yarn guide plate 1 has multiple yarn guide holes 10 and glue injection tube holes 11. In the figure: the multiple yarn guide holes 10 are distributed in a square shape; the glue injection tube holes 11 are all distributed between the yarn guide holes 10.

[0059] The impregnation mold 2 has multiple impregnation cavities 20, which are interconnected and enclose the product to be molded in the same shape, or in other words, their cross-section is U-shaped. The impregnation cavities 20 extend from one end of the impregnation mold 2 to the other, forming an inlet at one end and an outlet at the other. The cross-sectional area of ​​each impregnation cavity 20 decreases proportionally from its inlet to its outlet; that is, the U-shape becomes progressively smaller. Figure 7 As shown.

[0060] Multiple injection tubes 4 are provided, and are fixed in the injection tube holes 11 of the yarn guide plate 1. They are inserted into the inlet of the impregnation chamber 20. In the figure, eight injection tubes 4 are inserted into the impregnation chamber 20 and are evenly distributed. The injection tubes 4 are inserted vertically into the impregnation chamber 20. Figure 8 As shown.

[0061] The molding die 3 has a molding cavity 30, the shape of which is consistent with the shape of the square tube, or in other words, its cross-sectional shape is U-shaped. The molding cavity 30 extends from one end of the molding die 3 to the other end, forming an inlet at one end and an outlet at the other end. The cross-sectional shape and size of the outlet of the impregnation cavity 20 and the inlet of the molding cavity 30 are consistent, and the two are connected and aligned. Figure 9 As shown, the cross-sectional area of ​​the forming cavity 30 can remain constant from its inlet to its outlet, or it can be proportionally reduced from its inlet to its outlet, i.e., the U-shape becomes smaller and smaller. The forming mold 3 can be heated to solidify the impregnated yarn, reducing the cost of pultrusion molding.

[0062] During impregnation: Yarn 5 enters the U-shaped impregnation cavity 20 of the impregnation mold 2 through the yarn guide hole 10 of the yarn guide plate 1. The glue injection tube 4 injects resin evenly from the inlet of the impregnation cavity 20 to impregnate the yarn 5. The impregnation cavity 20 is subjected to glue injection pressure and flows from bottom to top to impregnate the yarn inside the impregnation cavity 20. After impregnation is completed, the glue injection tube 4 stops injecting glue. As the impregnation cavity 20 continuously shrinks proportionally, its cavity has a certain slope. Excess resin can flow out from the impregnation cavity 20 by its own gravity, preventing the board from having too much glue content, which would affect its mechanical properties. Furthermore, the impregnation mold 2 does not need to open a separate overflow port for glue discharge.

[0063] Flow tests were conducted on existing injection ports located perpendicular to the mold direction, i.e., vertical injection, and in this embodiment, injection was performed from the inlet of the impregnation chamber 20 via the injection tube 4.

[0064] like Figure 10 , 11 As shown: the stripes represent yarn, and the gray represents resin. Because the pultrusion process involves continuous long yarns arranged in parallel and impregnated with resin, it is, to some extent, an anisotropic material. Figure 10 The resin flows outwards in an elliptical pattern from the injection point, with some yarns being impregnated more slowly. Figure 11 The resin flows directly along the direction of yarn pultrusion, which can increase the injection speed and improve production efficiency.

[0065] The improved impregnation effect also enhances the mechanical properties. In this embodiment, the fiber volume content of the impregnated pultruded product can be increased to 70%-75%, and the 0° tensile strength and fatigue resistance are also improved to a certain extent.

[0066] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A multi-cavity injection impregnation molding apparatus, characterized in that: It includes a yarn guide plate, an impregnation mold, a forming mold, and an injection tube, wherein the yarn guide plate, the impregnation mold, and the forming mold are arranged in sequence. The yarn guide plate is provided with multiple yarn guide holes and glue injection tube holes, the glue injection tube holes are distributed between the yarn guide holes, and the glue injection tube is fixed in the glue injection tube holes; The impregnation mold has multiple impregnation cavities, which extend from one end of the impregnation mold to the other end, with an inlet at one end and an outlet at the other end. Each impregnation cavity includes a first impregnation cavity and a second impregnation cavity that are independent of each other. The cross-sectional shape of the first impregnation cavity and the second impregnation cavity is the same as the cross-sectional shape of the product to be molded. The first impregnation cavity and the second impregnation cavity are arranged vertically. The first impregnation cavity extends from its inlet to its outlet at an angle from top to bottom, and the second impregnation cavity extends from its inlet to its outlet at an angle from bottom to top. Multiple glue injection tubes are provided, and the multiple glue injection tubes are inserted from the inlet of the impregnation chamber; The molding die has a molding cavity with the same cross-sectional shape as the product to be molded. The molding cavity extends from one end of the molding die to the other end, with an inlet at one end and an outlet at the other end. The inlet of the molding cavity is connected to and communicates with the outlet of the impregnation cavity.

2. The multi-cavity injection impregnation molding apparatus according to claim 1, characterized in that: The cross-sectional shape of the impregnation cavity and the forming cavity is both straight.

3. The multi-cavity injection impregnation molding apparatus according to claim 1, characterized in that: Each of the aforementioned impregnation chambers is uniformly provided with multiple glue injection tubes.

4. A multi-cavity injection dipping molding process, characterized in that: The process employs the multi-cavity injection impregnation molding apparatus as described in any one of claims 1 to 3, comprising injecting the impregnation medium into the impregnation cavity through the injection tube, wherein the flow direction of the injected impregnation medium is consistent with the direction of yarn pultrusion.

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