Coating molds for carbon fiber products and methods for coating the surface of carbon fiber products

Abstract

This invention discloses a carbon fiber product coating mold and a method for coating the surface of carbon fiber products. The carbon fiber product coating mold includes a moving mold, a fixed mold, and a heating device. The moving mold is provided with a moving mold cavity, a moving mold feed groove, a coating port, a moving mold overflow cavity, and a moving mold overflow buffer cavity. The fixed mold is provided with a fixed mold cavity, a fixed mold feed groove, a fixed mold overflow cavity, and a fixed mold overflow buffer cavity. After the fixed mold and the moving mold are connected, a feed channel forming cavity, an overflow buffer cavity, and an overflow bag are sequentially formed and sealed to the coating port. The carbon fiber product surface coating method involves first positioning the carbon fiber product in the moving mold cavity, then filling the mold with paint after closing the mold, maintaining it at a certain temperature for a set time, and then removing the product after opening the mold. The paint forming part formed by the overflow buffer cavity and the feed channel is then cut and removed on a processing device. This invention effectively solves the problem of air bubbles on the paint film and improves the coating quality of carbon fiber products.

Description

Technical Field

[0001] This invention relates to a carbon fiber product processing method, and more particularly to a carbon fiber product coating mold and a carbon fiber product surface coating processing method. Background Technology

[0002] Currently, carbon fiber materials are often used in automotive interiors to achieve lightweight and high strength. However, the surface treatment of carbon fiber materials is mostly done by spraying, which makes it difficult to achieve uniform thickness, thinness, and aesthetic appeal.

[0003] Replacing traditional spraying processes with PUR filling technology can effectively improve the surface appearance and production efficiency of products. However, the PUR filling process can generate air bubbles due to trapped air. In order to expel the air bubbles during the injection of raw materials from the product molding area, the PUR filling technology designs an overflow bag in the mold. The overflow bag is located at the end of the molding cavity along the paint flow direction. A pressure difference is generated between the molding cavity and the overflow bag through the mold parting line 8, which squeezes the air bubbles during injection and some raw materials together into the overflow bag.

[0004] However, as the saturation of the overflow bag gradually increases, the pressure between the overflow bag and the molding cavity gradually decreases. This causes some air bubbles to not be completely discharged from the molding cavity and enter the overflow bag. At the same time, as the paint flows forward in the molding cavity and eventually enters the overflow bag, it is subjected to a reaction force, and some paint will flow backward from the overflow port of the overflow bag and back into the molding cavity. Therefore, no matter how large the overflow bag is designed, some air bubbles will remain in the molding cavity, eventually causing air bubbles to form on the product surface near the overflow bag, resulting in product defects. Summary of the Invention

[0005] To overcome the above-mentioned defects, the present invention provides a carbon fiber product coating mold, which can effectively solve the problem of air bubbles on the surface of the product near the overflow bag, and effectively improve the product yield.

[0006] The technical solution adopted by this invention to solve its technical problem is as follows: A carbon fiber product coating mold, comprising a moving mold, a fixed mold, and a heating device. The moving mold is located on one side of the fixed mold and is movable toward the fixed mold. The heating device can heat both the moving mold and the fixed mold. The moving mold has a moving mold cavity, a moving mold feed groove, a coating inlet, and a moving mold overflow cavity. The fixed mold has a fixed mold cavity, a fixed mold feed groove, and a fixed mold overflow cavity. The moving mold cavity and the fixed mold cavity can be joined to form a sealed molding cavity. The fixed mold cavity has a product positioning structure that can stop and position the product to be coated. The surface of the product to be coated and the moving mold cavity form a space for the paint to be contained on the product positioning structure. The filling space includes a moving mold feed trough and a fixed mold feed trough that can be connected to form a sealed feed channel. One end of the feed channel is connected to one end of the molding cavity, and the other end is connected to the filling port. The moving mold overflow cavity and the fixed mold overflow cavity can be connected to form a sealed overflow package. The overflow package has an overflow port with shrinkage on the side facing the molding cavity. The moving mold also has a moving mold overflow buffer cavity, and the fixed mold also has a fixed mold overflow buffer cavity. The moving mold overflow buffer cavity and the fixed mold overflow buffer cavity can be connected to form a sealed overflow buffer cavity. The other end of the molding cavity is connected to one end of the overflow buffer cavity, and the other end of the overflow buffer cavity is connected to the overflow port of the overflow package.

[0007] As a further improvement of the present invention, one end of the overflow buffer cavity and the other end of the molding cavity are smoothly connected by rounded corners, and the molded part formed in the overflow buffer cavity and the paint film formed in the paint filling space of the molding cavity are smoothly connected by arcs to form an integral structure.

[0008] As a further improvement of the present invention, the overflow volume accounts for 18%-22% of the paint filling space volume.

[0009] As a further improvement of the present invention, the width of the overflow buffer cavity along the paint flow direction is ≥20mm.

[0010] As a further improvement of the present invention, the product positioning structure in the fixed mold cavity includes positioning pins corresponding one-to-one with the positioning holes on the product to be painted and a plurality of negative pressure air holes located on the surface of the fixed mold cavity. The moving mold cavity is provided with clearance grooves corresponding one-to-one with the positioning pins in the fixed mold cavity. The positioning pins can be inserted into the positioning holes on the product to be painted and the clearance grooves in the moving mold cavity. The negative pressure air holes are connected to the negative pressure generating device.

[0011] As a further improvement of the present invention, the cavity formed by the moving mold feed groove, moving mold cavity, moving mold overflow buffer cavity and moving mold overflow cavity of the moving mold is provided with a moving mold sealing groove around the cavity. The cavity formed by the fixed mold feed groove, fixed mold cavity, fixed mold overflow buffer cavity and fixed mold overflow cavity of the fixed mold is provided with a fixed mold sealing groove around the cavity. The moving mold sealing groove and the fixed mold sealing groove are connected to form an annular space, and a high temperature resistant sealing ring is tightly inserted in the annular space.

[0012] As a further improvement of the present invention, the moving mold and the fixed mold are respectively provided with a plurality of moving mold buffer pads and fixed mold buffer pads on the periphery of the moving mold sealing groove and the fixed mold sealing groove, and the moving mold buffer pads and the fixed mold buffer pads are arranged in a one-to-one correspondence.

[0013] As a further improvement of the present invention, guide sleeves are detachably provided at the four corners of the moving mold, and guide posts are fixedly provided at the four corners of the fixed mold. The guide posts are slidably inserted into the guide sleeves one by one. A mold locking rod is fixedly installed on the side wall of the moving mold, and the end of the mold locking rod can be fixedly connected to the side wall of the fixed mold through a connector.

[0014] A method for coating the surface of carbon fiber products includes the following steps:

[0015] Step 1: Fix the product to be painted inside the moving mold cavity of the carbon fiber product painting mold;

[0016] Step 2: The heating device heats the moving and fixed molds of the carbon fiber product coating mold;

[0017] Step 3: The moving mold and the fixed mold of the carbon fiber product painting mold are closed. Paint is injected into the molding cavity through the injection nozzle of the vacuum injector. After entering from the paint inlet, the paint flows sequentially through the paint filling space and overflow buffer cavity in the molding cavity along the feed channel and finally fills the overflow bag.

[0018] Step 4: Press the moving mold and the fixed mold together until the paint dries and sets;

[0019] Step 5: Open the moving mold and remove the painted product;

[0020] Step Six: Position the product on the processing equipment and start the processing equipment to cut and remove the paint forming part that is attached to the product and is formed by the overflow buffer cavity, overflow bag and feed channel.

[0021] As a further improvement of the present invention, in step two, the heating device keeps the moving mold plate and the fixed mold plate at 80-90°C; in step three, paint at 65±1°C is injected; in step four, the mold is closed and held for 3-5 minutes; and in step six, excess paint on the product is removed by laser cutting.

[0022] The beneficial effects of this invention are as follows: By setting an overflow buffer cavity between the molding cavity and the overflow bag in the paint filling mold, the overflow buffer cavity and the molding cavity are smoothly connected by rounded corners. Ultimately, a small number of air bubbles that do not enter the overflow bag will remain in the overflow buffer cavity. After the paint is formed on the product, there may be a small number of air bubbles in the paint film on the outside of the carbon fiber product. The excess paint film on the outside of the carbon fiber product can be removed by cutting equipment. Finally, there will be no air bubbles on the paint film layer that is fixedly covering the surface of the carbon fiber product. This surface painting process for carbon fiber products effectively solves the problem of air bubbles on the paint film on the surface of the product after surface painting, greatly improving the quality of the finished product after painting and increasing the yield rate of carbon fiber product production. Attached Figure Description

[0023] Figure 1 This is a front view of the structural principle of a paint filling mold in the prior art;

[0024] Figure 2 This is a front view illustrating the structural principle of the paint-filling mold of the present invention;

[0025] Figure 3 This is a first perspective view of the paint filling mold of the present invention;

[0026] Figure 4 This is a second perspective view of the paint filling mold of the present invention;

[0027] Figure 5 This is a first perspective view of the mold of the present invention;

[0028] Figure 6 This is a second perspective view of the mold of the present invention;

[0029] Figure 7 This is a first perspective view of the moving model of the present invention;

[0030] Figure 8 This is a second perspective view of the moving model of the present invention. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0032] Example: A carbon fiber product painting mold includes a moving mold 1, a fixed mold 2, and a heating device 9. The moving mold 1 is located on one side of the fixed mold 2 and is movable towards the fixed mold 2. The heating device 9 can heat both the moving mold 1 and the fixed mold 2. The moving mold 1 has a moving mold cavity 11, a moving mold feed groove 12, a painting port 13, and a moving mold overflow cavity 14. The fixed mold 2 has a fixed mold cavity 21, a fixed mold feed groove 22, and a fixed mold overflow cavity 23. The moving mold cavity 11 and the fixed mold cavity 21 can be connected to form a sealed molding cavity 3. The fixed mold cavity 21 has a product positioning structure that can stop and position the product to be painted. The surface of the product to be painted and the moving mold cavity 11 form a painting space for accommodating paint. The groove 12 and the fixed mold feed groove 22 can be connected to form a sealed feed channel 4. One end of the feed channel 4 is connected to one end of the molding cavity 3, and the other end of the feed channel 4 is connected to the paint filling port 13. The moving mold overflow cavity 14 and the fixed mold overflow cavity 23 can be connected to form a sealed overflow bag 5. The overflow bag 5 has an overflow port 51 with shrinkage size on the side facing the molding cavity 3. The moving mold 1 is also provided with a moving mold overflow buffer cavity 15, and the fixed mold cavity 21 is also provided with a fixed mold overflow buffer cavity 24. The moving mold overflow buffer cavity 15 and the fixed mold overflow buffer cavity 24 can be connected to form a sealed overflow buffer cavity 6. The other end of the molding cavity 3 is connected to one end of the overflow buffer cavity 6, and the other end of the overflow buffer cavity 6 is connected to the overflow port 51 of the overflow bag 5.

[0033] Before painting, the carbon fiber product to be painted is placed on the product positioning structure of the fixed mold cavity 21 and fixed in place, ensuring that the carbon fiber product to be painted is in close contact with the surface of the fixed mold cavity 21. Then, the mold is closed and the paint is poured in. The paint enters the mold from the paint inlet 13 of the moving mold 1. The paint flows into the molding cavity 3 along the feed channel 4. After filling the paint space in the molding cavity 3, the paint pushes the air bubbles forward. Most of the air bubbles are squeezed into the overflow bag 5 by the paint, and a small number of air bubbles remain in the overflow buffer cavity 6. When the overflow bag 5 is full, the painting is stopped. After waiting for a set time, the paint is set and the product can be taken out by opening the mold. At this time, most of the air bubbles are located in the slag bag outside the product, and a small number of air bubbles are located on the overflow buffer part outside the product. No air bubbles remain on the paint film on the surface of the carbon fiber product. This makes the paint film on the surface of the carbon fiber product uniform, bright and beautiful, greatly reducing the defects caused by residual air bubbles on the paint film on the surface of the carbon fiber product, improving the product yield, reducing production costs and improving production efficiency.

[0034] One end of the overflow buffer cavity 6 is smoothly joined to the other end of the molding cavity 3 with rounded corners. The molded part formed in the overflow buffer cavity 6 and the paint film formed in the paint filling space of the molding cavity 3 are smoothly connected by an arc to form an integral structure. The smooth joint between one end of the overflow buffer cavity 6 and the other end of the molding cavity 3 with rounded corners avoids the formation of a step between the molding cavity 3 and the overflow buffer cavity 6, thereby avoiding obstruction of air bubbles and ensuring that air bubbles in the molding cavity 3 can flow smoothly into the overflow buffer cavity 6, avoiding the presence of residual air bubbles in the overflow buffer cavity 6.

[0035] The overflow pack 5 has a volume that accounts for 18%-22% of the paint filling space. That is, the size of the overflow pack 5 accounts for about 20% of the paint volume on the surface of the carbon fiber product, which can accommodate all air bubbles to the greatest extent, while reducing the amount of paint injected and saving raw materials.

[0036] The overflow buffer cavity 6 has a width of ≥20mm along the paint flow direction. The sufficiently wide overflow buffer cavity 6 can fully accommodate residual air bubbles and prevent air bubbles from remaining in the molding cavity 3.

[0037] The product positioning structure inside the fixed mold cavity 21 includes positioning pins 25 corresponding to the positioning holes on the product to be painted and a plurality of negative pressure air holes located on the surface of the fixed mold cavity 21. The moving mold cavity 11 is provided with clearance grooves 16 corresponding to the positioning pins 25 in the fixed mold cavity 21. The positioning pins 25 can be inserted into the positioning holes on the product to be painted and the clearance grooves 16 in the moving mold cavity 11. The negative pressure air holes are connected to a negative pressure generating device.

[0038] The cavity formed by the moving mold 1's moving mold feed groove 12, moving mold cavity 11, moving mold overflow buffer cavity 15, and moving mold overflow cavity 14 is provided with a moving mold sealing groove 17 on its periphery. The cavity formed by the fixed mold 2's fixed mold feed groove 22, fixed mold cavity 21, fixed mold overflow buffer cavity 24, and fixed mold overflow cavity 23 is provided with a fixed mold sealing groove 26 on its periphery. The moving mold sealing groove 17 and the fixed mold sealing groove 26 are connected to form an annular space. A high-temperature resistant sealing ring is tightly inserted in the annular space to seal the moving mold 1 and the fixed mold 2 and prevent glue overflow.

[0039] The moving mold 1 and the fixed mold 2 are respectively provided with a plurality of moving mold buffer pads 18 and fixed mold buffer pads 27 around the moving mold sealing groove 17 and the fixed mold sealing groove 26, and the moving mold buffer pads 18 and fixed mold buffer pads 27 are arranged in a one-to-one correspondence. When the mold is closed, the connection between the moving mold buffer pads 18 and the fixed mold buffer pads 27 is protected to prevent damage to the product due to impact.

[0040] The moving mold 1 is also provided with detachable guide sleeves 19 at each of its four corners, and the fixed mold 2 is also fixedly provided with guide posts 28 at each of its four corners. The guide posts 28 are slidably inserted into the guide sleeves 19 one by one. The moving mold 1 is also fixedly installed with a mold locking rod 7 on its side wall. The end of the mold locking rod 7 can be fixedly connected to the side wall of the fixed mold 2 through a connector.

[0041] A method for coating the surface of carbon fiber products includes the following steps:

[0042] Step 1: Fix the product to be painted inside the moving mold cavity 11 of the carbon fiber product painting mold;

[0043] Step 2: The heating device 9 heats the moving mold 1 and the fixed mold 2 of the carbon fiber product painting mold, keeping the moving mold cavity of the moving mold 1 and the fixed mold cavity of the fixed mold 2 at 80-90℃;

[0044] Step 3: The moving mold 1 and the fixed mold 2 of the carbon fiber product painting mold are closed. Paint at 65±1℃ is injected into the molding cavity 3 through the injection nozzle of the vacuum injector. After entering from the painting port 13, the paint flows sequentially along the feed channel 4 through the painting space and overflow buffer cavity 6 in the molding cavity 3 and finally fills the overflow bag 5.

[0045] Step 4: Press the moving mold 1 and the fixed mold 2 together until the paint dries and sets;

[0046] Step 5: Open the moving mold 1 and remove the painted product;

[0047] Step 6: Position the product on the processing equipment and start the processing equipment to cut and remove the paint forming part that is attached to the product and is formed by the overflow buffer cavity 6, overflow bag 5 and feed channel 4.

[0048] After the paint is set on the carbon fiber product, it is removed from the mold. The paint film on the product surface will have five parts connected to the overflow buffer and overflow bag. The flow channel, overflow buffer and overflow bag on the product can be cut and removed by the processing equipment. Finally, a carbon fiber product with a uniform paint film is formed. There are no air bubbles on the paint film on the surface of the carbon fiber product. The cut edges can be further processed by grinding, etc. The processing equipment is preferably laser cutting to remove the excess paint forming part on the product. Other processing methods can also be used to remove it, such as sawing, milling, etc. Such processing methods are equivalent replacement methods that can be easily thought of by those skilled in the art based on this application, and all of them are within the protection scope of this application.

[0049] The embodiments described above are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

Claims

1. A carbon fiber product painting mold, comprising a moving mold (1), a fixed mold (2) and a heating device (9), wherein the moving mold is disposed on one side of the fixed mold and is capable of moving toward the fixed mold, and the heating device is capable of heating the moving mold and the fixed mold respectively, wherein the moving mold is provided with a moving mold cavity (11), a moving mold feed groove (12), a painting port (13) and a moving mold overflow cavity (14), and the fixed mold is provided with a fixed mold cavity (21), a fixed mold feed groove (22) and a fixed mold overflow cavity (23), wherein the moving mold cavity and the fixed mold cavity can be connected to form a sealed molding cavity (3). The fixed mold cavity is provided with a product positioning structure that can stop and position the product to be painted. The surface of the product to be painted and the moving mold cavity form a painting space for paint to be contained. The moving mold feed groove and the fixed mold feed groove can be connected to form a sealed feed channel (4). One end of the feed channel is connected to one end of the molding cavity, and the other end of the feed channel is connected to the paint filling port. The moving mold overflow cavity and the fixed mold overflow cavity can be connected to form a sealed overflow bag (5). The overflow bag has an overflow port (51) with shrinkage size on the side facing the molding cavity. The feature is: The moving mold is also provided with a moving mold overflow buffer cavity (15), and the fixed mold cavity is also provided with a fixed mold overflow buffer cavity (24). The moving mold overflow buffer cavity and the fixed mold overflow buffer cavity can be connected to form a sealed overflow buffer cavity (6). The other end of the molding cavity is connected to one end of the overflow buffer cavity, and the other end of the overflow buffer cavity is connected to the overflow port of the overflow package. One end of the overflow buffer cavity and the other end of the molding cavity are smoothly connected by rounded corners. The molded part formed in the overflow buffer cavity and the paint film formed by the paint filling space of the molding cavity are smoothly connected by arcs to form an integral structure.

2. The carbon fiber product coating mold according to claim 1, characterized in that: The overflow volume accounts for 18%-22% of the paint filling space volume.

3. The carbon fiber product coating mold according to claim 1, characterized in that: The width of the overflow buffer cavity along the paint flow direction is ≥20mm.

4. The carbon fiber product coating mold according to claim 1, characterized in that: The product positioning structure in the fixed mold cavity includes positioning pins (25) that correspond one-to-one with the positioning holes on the product to be painted and a number of negative pressure air holes located on the surface of the fixed mold cavity. The moving mold cavity is provided with clearance grooves (16) that correspond one-to-one with the positioning pins in the fixed mold cavity. The positioning pins can be inserted into the positioning holes on the product to be painted and the clearance grooves in the moving mold cavity. The negative pressure air holes are connected to the negative pressure generating device.

5. The carbon fiber product coating mold according to claim 1, characterized in that: The moving mold has a moving mold sealing groove (17) around the cavity formed by the moving mold feed groove, moving mold cavity, moving mold overflow buffer cavity and moving mold overflow cavity. The fixed mold has a fixed mold sealing groove (26) around the cavity formed by the fixed mold feed groove, fixed mold cavity, fixed mold overflow buffer cavity and fixed mold overflow cavity. The moving mold sealing groove and the fixed mold sealing groove are connected to form an annular space. A high temperature resistant sealing ring is tightly inserted in the annular space.

6. The carbon fiber product coating mold according to claim 3, characterized in that: The moving mold and the fixed mold are provided with several moving mold buffer pads (18) and fixed mold buffer pads (27) respectively outside the moving mold sealing groove and the fixed mold sealing groove. The moving mold buffer pads and the fixed mold buffer pads are set one-to-one.

7. The carbon fiber product coating mold according to claim 1, characterized in that: The moving mold is also provided with detachable guide sleeves (19) at each of the four corners, and the fixed mold is also fixedly provided with guide posts (28) at each of the four corners. The guide posts are slidably inserted into the guide sleeves one by one. The moving mold is also fixedly installed with a mold locking rod (7) on the side wall. The end of the mold locking rod can be fixedly connected to the side wall of the fixed mold through a connector.

8. A method for surface coating of carbon fiber products using a carbon fiber product coating mold according to any one of claims 1-7, characterized in that, Includes the following steps: Step 1: Fix the product to be painted inside the moving mold cavity of the carbon fiber product painting mold; Step 2: The heating device heats the moving and fixed molds of the carbon fiber product coating mold; Step 3: The moving mold and the fixed mold of the carbon fiber product painting mold are closed. Paint is injected into the molding cavity through the injection nozzle of the vacuum injector. After entering from the paint inlet, the paint flows sequentially through the paint filling space and overflow buffer cavity in the molding cavity along the feed channel and finally fills the overflow bag. Step 4: Press the moving mold and the fixed mold together until the paint dries and sets; Step 5: Open the moving mold and remove the painted product; Step Six: Position the product on the processing equipment and start the processing equipment to cut and remove the paint forming part that is attached to the product and is formed by the overflow buffer cavity, overflow bag and feed channel.

9. The method for coating the surface of carbon fiber products according to claim 8, characterized in that: In step two, the heating device maintains the moving mold platen and the fixed mold platen at 80-90℃. In step three, paint at 65±1℃ is injected. In step four, the mold is closed and held for 3-5 minutes. In step six, excess paint on the product is removed by laser cutting.

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