A mold and a molding method for a thin-walled load-bearing shaft member

Abstract

The application relates to a mold and a forming method of a thin-wall bearing shaft structure, and belongs to the technical field of composite material manufacturing. The mold comprises a preform forming mold, a silica gel column body tool and a curing mold. The preform forming mold comprises a T-shaped column body, a flange cover plate and fixing screws. The curing mold comprises an upper U-shaped groove body, a lower U-shaped groove body, an end face cover plate and curing fixing screws. The preform forming mold is used for preform preparation forming, and the silica gel column body tool and the curing mold are used for product curing forming. The application also discloses a thin-wall bearing shaft structure forming method using the mold. The application has the advantages that the thin-wall bearing shaft column section and the two side flanges are integrally formed, the common delamination phenomenon between the column section area and the end face flange is solved, and the damage of the product surface caused by demolding under room temperature conditions is avoided.

Description

Technical Field

[0001] This invention belongs to the field of composite material manufacturing technology, and particularly relates to a molding method for thin-walled load-bearing shaft structures. Background Technology

[0002] Carbon fiber composites, due to their high specific strength, specific modulus, strong designability, and excellent dimensional stability, have been widely used in aerospace structural components. Thin-walled load-bearing shafts, consisting of a column segment and an end flange integrally formed, are common internal main load-bearing structures in cabin sections, enclosures, and satellite support products, and have high requirements for assembly surfaces. Compared to traditional metal load-bearing shaft structures, composite thin-walled load-bearing shafts not only have the characteristics of being lightweight, high-strength, corrosion-resistant, and dimensionally stable, but also have the advantage of integral molding of the column segment and end flange. However, the common method of molding with a single male mold cannot fully guarantee the high-precision installation requirements of the column segment's exterior. On the other hand, using a male mold for laying and curing with a curing mold can easily lead to delamination, a common phenomenon in composite products, in the column segment area and at the end flange, directly affecting the mechanical properties of the structural components. Summary of the Invention

[0003] The purpose of this invention is to provide a mold and forming method for thin-walled load-bearing shaft structures, so as to solve the technical problem of combining high precision and low damage in the forming process of thin-walled load-bearing shaft structures.

[0004] To solve the above-mentioned technical problems, the specific technical solutions for the mold and forming method of the thin-walled load-bearing shaft structure of the present invention are as follows:

[0005] A mold for a thin-walled load-bearing shaft structure includes a preform forming mold, a silicone column tooling, and a curing mold; the preform forming mold includes a T-shaped column, a flange cover plate, and pre-made fixing screws; the curing mold includes an upper U-shaped groove, a lower U-shaped groove, an end cover plate, and curing fixing screws; the preform forming mold is used for preform preparation and molding, and the silicone column tooling and curing mold are used for product curing and molding.

[0006] Furthermore, the T-shaped column has a columnar section and a disc-shaped section. The columnar section of the T-shaped column has a prefabricated fixing screw in the middle of its end face for connection and fastening with the flange cover plate to form a prefabricated surface. The columnar section is used to form the column section of the thin-walled load-bearing shaft.

[0007] The flange cover plate is provided with pre-made fastening holes and pre-made anti-top holes. The pre-made fastening holes are used to connect and fasten the T-shaped column with the pre-made fixing screws on the T-shaped column; the pre-made anti-top holes are used for demolding the prefabricated parts after the laying is completed.

[0008] The T-shaped column and the flange cover plate are connected and assembled by prefabricated fixing screws. The disc-shaped section of the T-shaped column and the flange cover plate are used to form the flange end face of the shaft. The thin-walled load-bearing shaft is pre-laid on the inside of the assembled pre-forming mold using a laying process.

[0009] Furthermore, in the curing mold, the upper U-shaped groove and the lower U-shaped groove are used to cover the outer column section facade of the precast body, and the silicone column tooling is inserted into the inner column section facade of the thin-walled load-bearing shaft precast body.

[0010] The upper U-shaped groove is provided with a curing and fastening hole; the lower U-shaped groove is provided with a corresponding fastening hole; the upper U-shaped groove and the lower U-shaped groove are connected and fastened by curing and fixing screws to form a curing cavity, and the end cover plate encapsulates the flange end face of the thin-walled load-bearing shaft prefabricated body.

[0011] Furthermore, the upper U-shaped groove is provided with a curing anti-ejection hole for demolding;

[0012] The mold dimensions of the upper and lower U-shaped grooves covering the outer column section facade of the precast body are comparable to those of the thin-walled load-bearing shaft component. The shape and size of the plate holes on the end cover plate are the shape and size of the inner cavity of the finished thin-walled load-bearing shaft component structure.

[0013] Furthermore, the silicone column tooling has the same shape as the inner cavity of the inner column section of the prefabricated thin-walled load-bearing shaft component, and the size of the silicone column tooling is the same as or slightly smaller than the inner cavity of the inner column section of the prefabricated thin-walled load-bearing shaft component.

[0014] Furthermore, the preform forming mold and the curing mold are both manufactured using CNC machining, and the materials used are aluminum alloy or steel.

[0015] Furthermore, the silicone cylinder tooling is made of R10301 silicone rubber and is formed by casting the upper and lower U-shaped grooves in the curing mold. The diameter of the silicone cylinder can be controlled by the number of release cloth layers laid on the forming surfaces of the upper and lower U-shaped grooves.

[0016] The present invention also provides a method for forming a thin-walled load-bearing shaft structure, the steps of which include:

[0017] S1, clean the preform forming mold 1 used. After cleaning, connect and assemble the T-shaped columns.

[0018] S2, after the T-shaped column and flange cover plate are connected and assembled, the preform is prepared on the mold forming surface according to the corresponding prepreg material;

[0019] S3, the prefabricated thin-walled load-bearing shaft component is completed. The prefabricated component is sealed in a low-temperature environment and subjected to freeze-setting treatment.

[0020] S4, under low temperature conditions, the flange cover is demolded by reverse ejection based on the flange cover demolding hole, and then the preform is demolded;

[0021] S5, first test install the upper U-shaped groove and lower U-shaped groove in the curing mold on the outer column section facade of the precast body, then install the silicone column tooling into the inner column section facade of the precast body, then fix the upper U-shaped groove and lower U-shaped groove 7 with screws, and finally seal the end face cover plate on the flange end face of the precast body.

[0022] S6. The preform of the thin-walled load-bearing shaft to be cured is encapsulated and vacuumed; then it is transferred to a hot press for curing.

[0023] S7. After the product has cured and cooled to the demolding temperature, it is transferred out of the can. Based on the curing anti-top hole of the upper U-shaped groove, the upper U-shaped groove and the lower U-shaped groove are demolded. Demolding is carried out by corresponding bolt anti-top demolding.

[0024] S8, clean the resin-rich burrs generated on the product's edge contour, and clean the mold.

[0025] Furthermore, the encapsulation operation in S5 can be performed by tightly wrapping the mold with a stretch film or by placing the entire mold in a vacuum bag.

[0026] Furthermore, the low temperature described in S4 is 0 to -20°C.

[0027] Furthermore, the low temperature mentioned in S4 is -10°C.

[0028] Furthermore, the demolding temperature in S7 is 60 to 90°C.

[0029] Furthermore, the demolding temperature in S7 is 80°C.

[0030] The mold and forming method for a thin-walled load-bearing shaft structure of the present invention have the following advantages:

[0031] 1. The paving mold is assembled in two parts, which can be used for both paving and demolding, and can also be used to form a thin-walled load-bearing shaft column section and the flanges on both sides in one piece.

[0032] 2. Based on the preform's low-temperature shaping conditions, the preform is demolded under low-temperature and sealed conditions;

[0033] 3. Based on the external segmented curing mold, the silicone tooling for the column segment is designed using the principle of thermal expansion of silicone rubber, which solves the common delamination phenomenon between the column segment area and the end flange.

[0034] 4. Based on the original solidified mold, a reverse ejection hole and high-temperature demolding method are adopted to avoid damage to the product surface caused by demolding at room temperature. Attached Figure Description

[0035] Figure 1This is a schematic diagram of the preform forming mold for the thin-walled load-bearing shaft structure of the present invention;

[0036] Figure 2 This is a schematic diagram of the silicone cylinder tooling for the thin-walled load-bearing shaft structure of the present invention;

[0037] Figure 3 This is a schematic diagram of the curing mold assembly for the thin-walled load-bearing shaft structure of the present invention;

[0038] Figure 4 This is a schematic diagram of the unassembled curing mold of the thin-walled load-bearing shaft structure of the present invention;

[0039] Figure 5 This is a schematic diagram of the thin-walled load-bearing shaft structure of the present invention;

[0040] Figure 6 This is a cross-sectional view of the thin-walled load-bearing shaft structure of the present invention (BB).

[0041] The markings in the diagram are as follows: 1. Precast molding mold; 2. T-shaped column; 3. Flange cover plate; 3-1. Precast fastening hole; 3-2. Precast anti-top hole; 4. Silicone column tooling; 5. Curing mold; 6. Upper U-shaped channel; 6-1. Curing fastening hole; 6-2. Curing anti-top hole; 7. Lower U-shaped channel; 8. End cover plate; 8-1. Plate hole; 9. Fixing screw; 9-1. Precast fixing screw; 9-2. Curing fixing screw; 10. Thin-walled load-bearing shaft; 11. Curing cavity. Detailed Implementation

[0042] To better understand the purpose, structure, and function of this invention, the following detailed description, in conjunction with the accompanying drawings, provides an explanation of the mold and forming method for a thin-walled load-bearing shaft structure according to this invention.

[0043] The technical solution adopted by this invention to solve its technical problem is: a mold for a thin-walled load-bearing shaft structure, the specific technical solution of which is as follows:

[0044] See Figures 1-6 This invention provides a preform molding mold for a thin-walled load-bearing shaft structure, including a preform molding mold 1, a silicone column tooling 4, and a curing mold 5; wherein, the preform molding mold 1 includes a T-shaped column 2, a flange cover plate 3, and preformed fixing screws 9-1; the curing mold 5 includes an upper U-shaped groove 6, a lower U-shaped groove 7, an end cover plate 8, and curing fixing screws 9-2.

[0045] The preform forming mold 1 is used for preform preparation and molding, and the silicone column tooling 4 and curing mold 5 are used for product curing and molding.

[0046] The T-shaped column 2 has a columnar section and a disc-shaped section. The columnar section of the T-shaped column 2 is provided with a prefabricated fixing screw 9-1 in the middle of its end face for connection and fastening with the flange cover plate 3 to form a prefabricated surface. The columnar section is used to form the shaft column section.

[0047] The flange cover plate 3 is provided with pre-made fastening holes 3-1 and pre-made anti-top holes 3-2. The pre-made fastening holes 3-1 are used to connect and fasten the T-shaped column 2 with the pre-made fixing screws 9-1 on the T-shaped column 2; the pre-made anti-top holes 3-2 are used for demolding the precast parts after the laying is completed.

[0048] The T-shaped column 2 and the flange cover plate 3 are connected and assembled by prefabricated fixing screws 9-1. The disc-shaped body section of the T-shaped column 2 and the flange cover plate 3 are used to form the flange end face of the shaft. The thin-walled load-bearing shaft 10 is pre-laid on the inside of the assembled prefabricated molding mold 1 using a laying process.

[0049] After the prefabricated thin-walled load-bearing shaft component 10 is prepared, demolding is carried out. During demolding, the reverse top operation is performed based on the prefabricated reverse top hole 3-2 on the surface of the flange cover plate 3, and the flange cover plate 3 and the prefabricated thin-walled load-bearing shaft component 10 are separated in sequence.

[0050] In the curing mold 5, the upper U-shaped groove 6 and the lower U-shaped groove 7 are used to cover the outer column section facade of the precast body, and the silicone column tooling 4 is inserted into the inner column section facade of the precast body of the thin-walled load-bearing shaft 10.

[0051] The upper U-shaped groove 6 is provided with a curing and fastening hole 6-1; the lower U-shaped groove 7 is provided with a corresponding fastening hole (not shown in the figure); the upper U-shaped groove 6 and the lower U-shaped groove 7 are connected and fastened by the curing and fixing screws 9-2 to form a curing cavity 11, and the end cover plate 8 encapsulates the flange end face of the prefabricated thin-walled load-bearing shaft 10.

[0052] The upper U-shaped groove 6 is provided with a curing anti-ejection hole 6-2 for demolding;

[0053] The mold dimensions of the upper U-shaped groove 6 and the lower U-shaped groove 7 covering the outer column section facade of the precast body are equivalent to those of the thin-walled load-bearing shaft 10. The shape and size of the plate hole 8-1 on the end cover plate 8 are the shape and size of the inner cavity of the finished thin-walled load-bearing shaft structure.

[0054] Taking a circular rotating thin-walled load-bearing shaft structure as an example, the diameter of the plate hole 8-1 is the diameter of the inner cavity of the column segment of the circular rotating thin-walled load-bearing shaft structure.

[0055] The silicone column tooling 4 has the same shape as the inner cavity of the inner column section of the prefabricated thin-walled load-bearing shaft 10, and the size of the silicone column tooling 4 is the same as or slightly smaller than the inner cavity of the inner column section of the prefabricated thin-walled load-bearing shaft 10.

[0056] The preform forming mold 1 and the curing mold 5 are both manufactured by CNC machining. The material can be aluminum alloy or steel, etc. The aluminum alloy is 2AL12 aluminum alloy and the steel is stainless steel.

[0057] The silicone cylinder fixture 4 is made of R10301 silicone rubber and is formed by casting the upper U-shaped groove 6 and the lower U-shaped groove 7 in the curing mold. The diameter of the silicone cylinder can be controlled by the number of release cloth layers laid on the forming surfaces of the upper U-shaped groove 6 and the lower U-shaped groove 7.

[0058] The second aspect of the present invention provides a method for forming a thin-walled load-bearing shaft structure, the specific steps of which are:

[0059] S1. Clean the precast molding mold 1. After cleaning, connect and assemble the T-shaped column 2 and the flange cover plate 3.

[0060] After S2, T-shaped column 2 and flange cover plate 3 are connected and assembled, the preform is prepared on the mold forming surface according to the corresponding prepreg material.

[0061] S3, the prefabricated thin-walled load-bearing shaft component 10 is completed. The prefabricated component is sealed in a low-temperature environment and subjected to freeze-setting treatment.

[0062] S4, under low temperature conditions, based on the prefabricated anti-top hole 3-2 of the flange cover plate 3, the flange cover plate 3 is demolded by anti-top hole, and then the prefabricated body is demolded;

[0063] S5, first test-fit the upper U-shaped groove 6 and lower U-shaped groove 7 in the curing mold 5 onto the outer column section facade of the preform, then install the silicone column fixture 4 into the inner column section facade of the preform, then fix the upper U-shaped groove 6 and lower U-shaped groove 7 with the fixing screws 9-2, and finally seal the flange end face of the preform with the end face cover plate 8; the sealing operation can be carried out by tightly wrapping with stretch film or placing the entire mold in a vacuum bag, or the sealing method commonly used in this field;

[0064] S6, the preform of the thin-walled load-bearing shaft 10 to be cured is encapsulated and vacuumed; then it is transferred to a hot press for curing.

[0065] S7. After the product has cured and cooled to the demolding temperature, it is transferred out of the can. Based on the curing anti-top hole 6-2 of the upper U-shaped groove 6, the upper U-shaped groove 6 and the lower U-shaped groove 7 are demolded. Demolding is carried out by corresponding bolt anti-top demolding.

[0066] S8, clean the resin-rich burrs generated on the product's edge contour, and clean the mold.

[0067] In S5, the encapsulation process can be performed by tightly wrapping the mold with stretch film or by placing the entire mold in a vacuum bag.

[0068] The low temperature described in S4 is 0 to -20°C.

[0069] The demolding temperature in S7 is 60 to 90°C, preferably 80°C.

[0070] It is understood that the present invention has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of the invention. Furthermore, under the teachings of the present invention, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of the invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the protection scope of the present invention.

Claims

1. A mold for a thin-walled load-bearing shaft member structure, characterized in that, It comprises a prefabricated body forming die (1), a silica gel column tooling (4), and a curing die (5); the prefabricated body forming die (1) comprises a T-shaped column (2), a flange cover plate (3), and prefabricated fixing screws (9-1); the curing die (5) comprises an upper U-shaped groove body (6), a lower U-shaped groove body (7), an end face cover plate (8), and curing fixing screws (9-2); the prefabricated body forming die (1) is used for prefabricated body preparation forming, and the silica gel column tooling (4) and the curing die (5) are used for product curing forming. The T-shaped column (2) has a columnar body segment and a discoid body segment, the middle part of the end face of the columnar body segment of the T-shaped column (2) is provided with prefabricated fixing screws (9-1) for connecting and fastening the flange cover plate (3) to form a prefabricated surface, and the columnar body segment is used for forming a column segment of the thin-walled load-bearing shaft (10). The flange cover plate (3) is provided with prefabricated fastening holes (3-1) and prefabricated counter-top holes (3-2), the prefabricated fastening holes (3-1) are used for connecting and fastening the T-shaped column (2) through the prefabricated fixing screws (9-1) on the T-shaped column (2), and the prefabricated counter-top holes (3-2) are used for demolding the prefabricated part after laying. The T-shaped column (2) and the flange cover plate (3) are connected and assembled through the prefabricated fixing screws (9-1), the discoid body segment of the T-shaped column (2) and the flange cover plate (3) are used for forming a flange end face of a shaft, and a laying process is adopted to lay the thin-walled load-bearing shaft (10) on the inner side of the combined prefabricated body forming die (1).

2. The mold of the thin-walled load-bearing shaft structure according to claim 1, characterized in that the upper U-shaped groove body (6) and the lower U-shaped groove body (7) in the curing die (5) are used for covering the outer side column segment vertical surface of the prefabricated body, and the silica gel column tooling (4) is loaded into the inner side column segment vertical surface of the prefabricated body of the thin-walled load-bearing shaft (10), the upper U-shaped groove body (6) is provided with curing fastening holes (6-1), the lower U-shaped groove body (7) is provided with corresponding fastening holes, the upper U-shaped groove body (6) and the lower U-shaped groove body (7) are connected and fastened through the curing fixing screws (9-2) to form a curing cavity (11), and the end face cover plate (8) encapsulates the flange end face of the prefabricated body of the thin-walled load-bearing shaft (10).

3. The mold of the thin-walled load-bearing shaft structure according to claim 1, characterized in that the upper U-shaped groove body (6) is provided with curing counter-top holes (6-2) for demolding; the mold size of the upper U-shaped groove body (6) and the lower U-shaped groove body (7) covering the outer side column segment vertical surface of the prefabricated body is equivalent to that of the thin-walled load-bearing shaft (10), and the shape and size of the plate holes (8-1) on the end face cover plate (8) are equivalent to those of the inner cavity of the thin-walled load-bearing shaft structure product.

4. A mold for a thin-walled load-bearing shaft member structure according to any one of claims 1-3, characterized in that The silica gel column tooling (4) has the same shape as the inner cavity of the inner side column segment of the prefabricated body of the thin-walled load-bearing shaft (10), and the size of the silica gel column tooling (4) is equivalent to or slightly smaller than that of the inner cavity of the inner side column segment of the prefabricated body of the thin-walled load-bearing shaft (10).

5. The mold for thin-walled load-bearing shaft member structure according to claim 4, wherein The prefabricated body forming die (1) and the curing die (5) are manufactured by numerical control processing, and the material is selected from aluminum alloy or steel.

6. The mold for thin-walled load-bearing shaft member structure according to claim 4, wherein The silica gel column tool (4) is made of R10301 silica rubber, and is formed by pouring into the upper U-shaped groove body (6) and the lower U-shaped groove body (7) in the curing mold, wherein the diameter of the silica gel column can be controlled by the number of release cloth layers laid on the forming surfaces of the upper U-shaped groove body (6) and the lower U-shaped groove body (7).

7. A forming method of a thin-walled load-bearing shaft structure, using the mold of claim 3, characterized in that, S1. Clean the used preform forming mold (1), and after cleaning, connect and assemble the T-shaped column (2) and the flange cover plate (3); S2. After connecting and assembling the T-shaped column (2) and the flange cover plate (3), prepare the preform according to the corresponding pre-impregnated material on the mold forming surface; S3. After the preform of the thin-walled load-bearing shaft (10) is completed, seal the preform in a low-temperature environment and perform cold setting treatment; S4. Under low-temperature conditions, the preform counter-top hole (3-2) of the flange cover plate (3) counter-tops the flange cover plate (3), and then the preform is demolded; S5. The upper U-shaped groove body (6) and the lower U-shaped groove body (7) in the curing mold are first tried on the outer column section vertical surface of the preform, then the silica gel column tool (4) is installed in the inner column section vertical surface of the preform, then the fixing screws (9-2) of the upper U-shaped groove body (6) and the lower U-shaped groove body (7) are installed, and finally the end cover plate (8) is installed on the flange end surface of the preform; S6. The preform of the thin-walled load-bearing shaft (10) to be cured is packaged and vacuumized, and then transferred to the hot-pressing curing; S7. After the product is cured and cooled to the demolding temperature, it is transferred out of the tank, and the upper U-shaped groove body (6) and the lower U-shaped groove body (7) are demolded based on the curing counter-top hole (6-2) of the upper U-shaped groove body (6), and the demolding is performed by counter-topping with corresponding bolts; S8. Clean the rich resin edge generated by the edge profile of the product, and clean the mold.

8. The method of claim 7, wherein the method further comprises: The low temperature in S4 is 0 to -20℃.

9. The method of claim 7, wherein the method further comprises: The demolding temperature in S7 is 60 to 90℃.

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