Thermoplastic composite T-shaped window frame structure and compression molding process thereof

Abstract

The invention discloses a thermoplastic composite T-shaped window frame structure and a compression molding process thereof, and relates to the technical field of composite structure manufacturing. A runway oval window frame is composed of a flange rib, a vertical flange and a base flange, the cross section of the runway oval window frame is of an inverted-T-shaped structure, and a window frame base body is formed by splicing a Z-shaped cross section pre-forming assembly located at the bottom, a first L-shaped cross section pre-forming assembly located at the top and a second L-shaped cross section pre-forming assembly located at the top. And a one-way prepreg layer is wound and laid in a splicing gap of the window frame base body to form a preformed body, and then the preformed body is subjected to hot-pressing curing forming. A thermoplastic composite material laminated flat plate is subjected to matrix type blanking and batch pressing to form a preformed split body with a Z-shaped section and two L-shaped sections, three preformed assemblies are annularly spliced and then spliced to form a window frame base body, meanwhile, annular reinforcement is conducted through prepreg, and finally hot-pressing curing forming is conducted, so that fiber wrinkles can be effectively reduced, and the window frame quality is improved. The overall strength of the window frame is guaranteed, and manufacturing difficulty and manufacturing cost are reduced.

Description

Technical Field

[0001] The invention relates to the technical field of composite material structure manufacturing, in particular to a thermoplastic composite material T-shaped window frame structure and a compression molding process thereof. Background Art

[0002] At present, with the demand for lightweight parts in the aviation field, composite window frames have been widely used in civil aircraft. The window frame structure usually has a complex curved configuration and flange part, which is mainly used to be embedded and positioned in the correct position of the aircraft skin and window hole to support the window glass. However, the window frame structure on current civil aircraft is generally made of thermosetting composite materials. This window frame structure and molding method have the following disadvantages:

[0003] 1. The window frame structure is made of thermosetting composite materials. The resin is directly poured into the autoclave or molded, and then solidified. The molding process is complicated and difficult, resulting in a high manufacturing cost of the window frame structure.

[0004] 2. After the components of thermosetting composite materials are formed, they are generally connected together by welding. The resulting window frame structure is not easy to ensure low porosity, resulting in difficulty in controlling structural strength;

[0005] 3. Since the window frame structure has a curved geometric shape, these tight curvature structures are prone to wrinkling of the reinforcing fibers during the manufacturing process, which will further affect the strength of the window frame structure. Summary of the invention

[0006] In order to solve the shortcomings of the background technology, the present invention provides a thermoplastic composite T-shaped window frame structure and its molding process, which adopts a thermoplastic composite laminated flat plate to cut and batch press into a preformed split with a Z-shaped cross-section and two L-shaped cross-sections through matrix type, and then spliced ​​into three preformed components in a circumferential direction and then spliced ​​into a window frame matrix. At the same time, it is circumferentially reinforced by prepreg, and finally hot-pressed and cured. It can effectively reduce fiber wrinkles, ensure the overall strength of the window frame, and reduce the manufacturing difficulty and manufacturing cost.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] A thermoplastic composite T-shaped window frame structure comprises a runway elliptical window frame consisting of three parts: a flange rib, a vertical flange and a base flange. The cross section of the runway elliptical window frame is an inverted T-shaped structure. The window frame base is spliced ​​by a Z-shaped cross-section preformed component at the bottom and an L-shaped cross-section preformed component No. Ⅰ and an L-shaped cross-section preformed component No. Ⅱ at the top. The preformed body is formed by winding and laying a unidirectional prepreg ply in the splicing gap of the window frame base and then cured by hot pressing. The overlapping part of the L-shaped cross-section preformed component No. Ⅰ and the L-shaped cross-section preformed component No. Ⅱ is the middle vertical section of the inverted T-shaped structure and forms the vertical flange, the overlapping part of the L-shaped cross-section preformed component No. Ⅰ and the Z-shaped cross-section preformed component is the inner horizontal section of the inverted T-shaped structure and forms the flange rib, and the overlapping part of the L-shaped cross-section preformed component No. Ⅱ and the Z-shaped cross-section preformed component is the outer horizontal section of the inverted T-shaped structure and forms the base flange.

[0009] Furthermore, the L-section preformed component No. Ⅰ is composed of multiple sections of L-section preformed splits spliced ​​together in a circumferential manner, the L-section preformed component No. Ⅱ is composed of multiple sections of L-section preformed splits spliced ​​together in a circumferential manner, and the Z-section preformed component is composed of multiple sections of Z-section preformed splits spliced ​​together in a circumferential manner, and after being spliced ​​into a window frame base, the joints are staggered. The raw materials of the L-section preformed split No. Ⅰ, the L-section preformed split No. Ⅱ and the Z-section preformed split are all cut from the same thermoplastic composite laminated flat plate and are respectively pressed by corresponding block hot pressing tooling.

[0010] Furthermore, during the cutting process of the thermoplastic composite laminated plate, the cutting edge of the laminated plate is kept parallel to the fiber angle of the laminated plate.

[0011] A compression molding process for a thermoplastic composite T-shaped window frame structure comprises the following steps:

[0012] Step 1: Cutting

[0013] The same thermoplastic composite laminated flat plate is used to cut and blank the number and unfolded size of the No. Ⅰ L-section preformed split, No. Ⅱ L-section preformed split and Z-section preformed split required for the runway oval window frame segmentation, and the blanking size ensures that margins are left on the edges, thereby obtaining a plurality of flat plate units to be processed;

[0014] Step 2: Hot pressing of blocks

[0015] The plurality of flat plate units to be processed are respectively pressed into multiple sections of No. Ⅰ L-shaped section preformed parts, No. Ⅱ L-shaped section preformed parts and Z-shaped section preformed parts by corresponding block hot pressing forming tools, and the forming angles of the block hot pressing forming tools are designed as required according to the angles of the No. Ⅰ L-shaped section preformed parts, No. Ⅱ L-shaped section preformed parts and Z-shaped section preformed parts;

[0016] Step 3: Machining

[0017] The multi-segment No. Ⅰ L-section preformed parts, No. Ⅱ L-section preformed parts and Z-section preformed parts after hot pressing are machined and trimmed according to the net size, and the margins on the edges are removed;

[0018] Step 4: Combined winding

[0019] The multi-segment No. Ⅰ L-section preformed split, No. Ⅱ L-section preformed split and Z-section preformed split of the completed net size machine repair type are respectively circumferentially spliced ​​into No. Ⅰ L-section preformed assembly, No. Ⅱ L-section preformed assembly and Z-section preformed assembly, and then the No. Ⅰ L-section preformed assembly and No. Ⅱ L-section preformed assembly ring sleeve are arranged and placed on the top of the Z-section preformed assembly to splice into a window frame matrix, and at the same time, a unidirectional prepreg layer is laid in the splicing gap of the window frame matrix to form a preformed body, thereby completing the preparation of the preformed body;

[0020] Step 5: Preform Heating

[0021] The prepared preform is heated in an oven or placed in a hot pressing assembly mold and heated by conduction through the mold, and the heating temperature is within a range from room temperature to 400° C., which is adjusted according to the material of the thermoplastic composite laminate plate;

[0022] Step 6: Hot Pressing of Components

[0023] After the preform is heated, it is molded by a hot pressing combined mold to prepare a runway oval window frame, wherein the hot pressing combined mold includes a male mold and a female mold, and the combined mold cavity after the hot pressing combined mold is molded is the same as the runway oval window frame. In addition, a lateral pressure of not less than 2MPa can be applied to the runway oval window frame during the mold closing process;

[0024] Step 7: Cooling and demoulding machine

[0025] The hot-pressed runway elliptical window frame is separated from the hot-pressing combined mold, cooled naturally at room temperature, and the shape is trimmed according to the design dimensions of the window frame structure by digital modeling.

[0026] Furthermore, the male mold of the hot pressing combined mold includes a bottom mold, a male mold ballast core block and a plurality of male mold side pressure blocks, the recessed configuration of the female mold cooperates with the bottom of the runway elliptical window frame and a conical positioning groove is added in the center, the edge of the female mold surrounds the recessed configuration and an inner wall of the side frame is an inclined surface, the male mold ballast core block is fixed at the center of the bottom mold surface, and a plurality of male mold side pressure blocks are arranged around the male mold ballast core block, and the plurality of male mold side pressure blocks are respectively connected to the bottom mold by sliding combination through a connecting slide, and the inner bottom of the plurality of male mold side pressure blocks is connected to the male mold ballast core block. Mounting holes are processed at corresponding positions of the core blocks and are connected and assembled by compression springs respectively; a limiting platform is formed on the surface of the male mold ballast core block and multiple male mold side pressure blocks, and the limiting platform configuration cooperates with the top of the runway elliptical window frame; a combined model cavity is formed between the female mold, the male mold ballast core block and multiple male mold side pressure blocks; the outer sides of multiple male mold side pressure blocks are all made into inclined surfaces to cooperate with the side frame of the female mold; the middle position of the top of the male mold ballast core block can extend into the conical positioning groove of the female mold; under the restriction of the side frame of the female mold, multiple male mold side pressure blocks provide lateral pressure to the male mold ballast core block.

[0027] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention divides the T-shaped window frame structure into multiple typical split units, adopts a thermoplastic composite laminate flat plate to form a Z-shaped cross-section and two L-shaped cross-section preformed splits through matrix cutting and batch pressing, which are circumferentially spliced ​​into three preformed components and then spliced ​​into a window frame matrix. At the same time, the thermoplastic prepreg is used to circumferentially strengthen the one-piece molding, and finally the window frame structure is formed by hot pressing and curing, which can effectively reduce fiber wrinkles, enhance the strength and bearing capacity of the window frame structure, and at the same time have the material structure characteristics of high strength and high toughness, improve structural efficiency, perform two compression molding on the preformed components and the preformed bodies after combined assembly, ensure the high precision of the external dimensions of the window frame structure, adopt a hot compression molding process, the process is simple and easy, convenient for automated production, reduces the manufacturing difficulty and manufacturing cost, meets the needs of low-cost and high-efficiency mass production, and has good promotion and application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the overall structure of the T-shaped window frame structure of the present invention;

[0029] Figure 2 is a schematic cross-sectional view of a T-shaped window frame structure of the present invention;

[0030] Figure 3 It is a schematic diagram of the process of cutting, blanking and forming when forming the T-shaped window frame structure of the present invention;

[0031] Figure 4 It is a detailed schematic diagram of cutting and blanking when the T-shaped window frame structure of the present invention is formed;

[0032] Figure 5This is an exploded view of the window frame base when the T-shaped window frame structure of the present invention is formed;

[0033] Figure 6 It is a schematic diagram of preparing a preform by combined winding when forming the T-shaped window frame structure of the present invention;

[0034] Figure 7 Schematic diagram of the hot pressing combined mold used for forming the T-shaped window frame structure of the present invention;

[0035] Figure 8 It is a process flow chart of the T-shaped window frame structure of the present invention.

[0036] In the figure: 01, flange rib; 02, vertical flange; 03, base flange; 04, unidirectional prepreg ply; 05, thermoplastic composite laminate; 05-1, laminate cutting edge; 05-2, laminate fiber angle; 06, forming angle; 07, block hot pressing molding tool; 08-1, No. Ⅰ L-section preform split; 08-2, No. Ⅱ L-section preform split; 08-3, Z-section preform split; 08-4, seam; 09, preform straight edge section; 10, preform; 11, preform curvature section; 12, bottom mold; 13, limit platform; 14, female mold; 15, male mold side pressure block; 16, male mold ballast core block; 17, compression spring; 18, connecting slide; 19, combined model cavity; 20, installation hole. DETAILED DESCRIPTION

[0037] The technical solution of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0038] like Figure 1 to Figure 6As shown, a thermoplastic composite T-shaped window frame structure comprises a runway elliptical window frame consisting of a flange rib 01, a vertical flange 02 and a base flange 03. The cross section of the runway elliptical window frame is an inverted T-shaped structure. A Z-shaped cross-section preformed component at the bottom and an L-shaped cross-section preformed component No. Ⅰ and an L-shaped cross-section preformed component No. Ⅱ at the top are spliced ​​into a window frame matrix. A unidirectional prepreg ply 04 is laid around the splicing gap of the window frame matrix to form a preformed body 10, which is then cured by hot pressing. The overlapping portion of the L-shaped cross-section preformed component No. Ⅰ and the L-shaped cross-section preformed component No. Ⅱ is the middle vertical section of the inverted T-shaped structure and forms the vertical flange 02. The overlapping portion of the L-shaped cross-section preformed component No. Ⅰ and the Z-shaped cross-section preformed component is the inner horizontal section of the inverted T-shaped structure and forms the flange rib 01. The overlapping portion of the L-shaped cross-section preformed component No. Ⅱ and the Z-shaped cross-section preformed component is the outer horizontal section of the inverted T-shaped structure and forms the base flange 03.

[0039] The L-section preformed component No. Ⅰ is composed of multiple sections of L-section preformed splits 08-1 spliced ​​together in a circumferential manner, the L-section preformed component No. Ⅱ is composed of multiple sections of L-section preformed splits 08-2 spliced ​​together in a circumferential manner, and the Z-section preformed component is composed of multiple sections of Z-section preformed splits 08-3 spliced ​​together in a circumferential manner, and after being spliced ​​into a window frame base, the joints 08-4 are staggered. The raw materials of the L-section preformed split No. Ⅰ 08-1, the L-section preformed split No. Ⅱ 08-2 and the Z-section preformed split 08-3 are all cut from the same thermoplastic composite laminated flat plate 05 and are respectively pressed by corresponding block hot pressing molding tools 07.

[0040] During the cutting process of the thermoplastic composite laminate plate 05, the laminate plate cutting edge 05-1 and the laminate plate fiber angle 05-2 are kept parallel.

[0041] like Figures 1 to 8 As shown, a compression molding process of a thermoplastic composite T-shaped window frame structure comprises the following steps:

[0042] Step 1: Cutting

[0043] Using the same thermoplastic composite laminated flat plate 05, a cutting machine or a blanking machine is used to cut and blank the No. Ⅰ L-section preformed split 08-1, No. Ⅱ L-section preformed split 08-2 and Z-section preformed split 08-3 required for the runway oval window frame segmentation according to the number and unfolded size, and the blanking size ensures that a margin of 30mm-50mm is left on the edge, so as to obtain a plurality of flat plate units to be processed;

[0044] Step 2: Hot pressing of blocks

[0045] The plurality of flat plate units to be processed are respectively pressed into a plurality of sections of No. Ⅰ L-shaped section preformed parts 08-1, No. Ⅱ L-shaped section preformed parts 08-2 and Z-shaped section preformed parts 08-3 by corresponding block hot pressing forming tools 07, and the forming angle 06 of the block hot pressing forming tools 07 is designed as required according to the angles of No. Ⅰ L-shaped section preformed parts 08-1, No. Ⅱ L-shaped section preformed parts 08-2 and Z-shaped section preformed parts 08-3;

[0046] Step 3: Machining

[0047] The multi-section No. Ⅰ L-section preformed sub-body 08-1, No. Ⅱ L-section preformed sub-body 08-2 and Z-section preformed sub-body 08-3 after hot pressing are machined and trimmed according to the net size, and the margins on the edges are removed;

[0048] Step 4: Combined winding

[0049] The multi-segment No. Ⅰ L-section preformed sub-body 08-1, No. Ⅱ L-section preformed sub-body 08-2 and Z-section preformed sub-body 08-3 of the completed net size machine repair type are respectively circumferentially spliced ​​into No. Ⅰ L-section preformed assembly, No. Ⅱ L-section preformed assembly and Z-section preformed assembly, and then the No. Ⅰ L-section preformed assembly and No. Ⅱ L-section preformed assembly are set and placed on the top of the Z-section preformed assembly to splice into a window frame matrix, and at the same time, a unidirectional prepreg ply 04 is wound and laid in the splicing gap of the window frame matrix to form a preformed body 10, thereby completing the preparation of the preformed body 10;

[0050] Step 5: Preform Heating

[0051] The prepared preform 10 is heated in an oven or placed in a hot pressing assembly mold and heated by conduction through the mold, and the heating temperature is within a range from room temperature to 400° C., which is adjusted according to the material of the thermoplastic composite laminate plate;

[0052] Step 6: Hot Pressing of Components

[0053] After the preform 10 is heated, it is molded by a hot pressing combined mold to prepare a runway oval window frame, wherein the hot pressing combined mold includes a male mold and a female mold 14, and the combined mold cavity 19 after the hot pressing combined mold is molded is the same as the runway oval window frame. In addition, a lateral pressure of not less than 2MPa can be applied to the runway oval window frame during the mold closing process;

[0054] Step 7: Cooling and demoulding machine

[0055] The hot-pressed runway elliptical window frame is separated from the hot-pressing combined mold, cooled naturally at room temperature, and the shape is trimmed according to the design dimensions of the window frame structure by digital modeling.

[0056] Combination Figure 1 As shown, the overall configuration of the T-shaped window frame structure of the present invention is a runway elliptical structure as a whole, the main body is a runway elliptical base flange 03, a vertical flange 02 is arranged on the inner edge of the base flange 03, and a flange rib 01 is arranged on the inner side of the vertical flange 02.

[0057] Combination Figure 2 As shown, it is a cut section of a T-type window frame structure, the main skeleton is a window frame substrate, including L-section preformed split No. Ⅰ 08-1, L-section preformed split No. Ⅱ 08-2 and Z-section preformed split 08-3, which are prepared by hot pressing and then assembling thermoplastic composite materials, and the splicing gap is wrapped with a unidirectional prepreg layer 04, the material of which is a thermoplastic unidirectional prepreg tape, and if necessary, the outer surface of the window frame substrate can also be additionally coated with a unidirectional prepreg layer 04. It is worth noting that L-section preformed split No. Ⅰ 08-1 and L-section preformed split No. Ⅱ 08-2 can also be designed as equal number of multi-layer forms as needed, with Z-section preformed split 08-3 as the substrate of the window frame base, and firstly laying and winding part of the unidirectional prepreg ply 04 on the Z-section preformed split 08-3, and then placing L-section preformed split No. Ⅰ 08-1 and L-section preformed split No. Ⅱ 08-2 in pairs, and at the same time, the winding and laying of the remaining unidirectional prepreg ply 04 are carried out.

[0058] Combination Figure 3 As shown, when cutting L-section preformed parts 08-1, L-section preformed parts 08-2 and Z-section preformed parts 08-3, the same thermoplastic composite laminated flat plate 05 can be cut according to the needs of the runway elliptical window frame segmentation, and the matrix cutting can obtain the flat plate units ①, ②, ③, ④, ⑤ and ⑥ to be processed, and a certain margin is reserved at the edge of each plate. Among them, the trapezoidal plates ①, ②, ③ and ④ are pressed into the curvature parts of each preformed part by the corresponding block hot pressing forming tool 07, and the rectangular plates ⑤ and ⑥ are pressed into the straight edge parts of each preformed part by the corresponding block hot pressing forming tool 07. The block hot pressing forming tool 07 is divided into 6 different forms, and the preformed parts of the three sections include straight line forming and curvature forming.

[0059] Combination Figure 4 As shown, the cutting edge 05-1 of the thermoplastic composite laminated plate 05 should be kept parallel to the fiber angle 05-2 of the laminated plate during cutting to reduce wire breakage. The fiber layer angle θ of the thermoplastic composite laminated plate 05 can be designed to be ±30° to ±60° as required. In addition, in order to reduce wire breakage, the number of L-section preformed parts 08-1 No. Ⅰ, L-section preformed parts 08-2 No. Ⅱ and Z-section preformed parts 08-3 should be as small as possible.

[0060] Combination Figure 5As shown, multiple sections of No. Ⅰ L-section preformed parts 08-1 are circumferentially spliced ​​to form No. Ⅰ L-section preformed assembly, multiple sections of No. Ⅱ L-section preformed parts 08-2 are circumferentially spliced ​​to form No. Ⅱ L-section preformed assembly, multiple sections of Z-section preformed parts 08-3 are circumferentially spliced ​​to form Z-section preformed assembly, and each joint 08-4 should be staggered in space to reduce stress concentration, and then spliced ​​into the window frame base.

[0061] Combination Figure 6 As shown, the spliced ​​window frame substrate is divided into multiple preform straight edge sections 09 and preform curvature sections 11, which together form a runway elliptical shape. The unidirectional prepreg ply 04 is wrapped around the splicing gap and the outer surface of the window frame substrate to complete the preparation of the preform 10.

[0062] Combination Figure 7As shown, a hot pressing combined mold is used to hot press the preform 10, and the hot pressing combined mold is divided into a positive and negative double-layer mold. The positive mold includes a bottom mold 12, a positive mold ballast core block 16 and a plurality of positive mold side pressure blocks 15. The concave configuration of the negative mold 14 matches the bottom of the runway elliptical window frame and a conical positioning groove is added in the center. The edge of the negative mold 14 is integrally provided with a side frame with an inclined inner wall around the concave configuration. The positive mold ballast core block 16 is fixed at the center position of the bottom mold 12 surface, and a plurality of positive mold side pressure blocks 15 are arranged around the positive mold ballast core block 16. The plurality of positive mold side pressure blocks 15 are slidably combined with the bottom mold 12 through connecting slideways 18, and mounting holes 20 are processed at the corresponding positions of the inner bottom of the plurality of positive mold side pressure blocks 15 and the positive mold ballast core block 16 and are respectively connected and combined through compression springs 17. The surface of the positive mold ballast core block 16 and the plurality of positive mold side pressure blocks 15 form a limiting platform 13, and the limiting platform 13 is configured to match the runway. The top of the elliptical window frame is matched, and a combined model cavity 19 is formed between the female mold 14, the male mold ballast core block 16 and multiple male mold side pressure blocks 15. The outer sides of the multiple male mold side pressure blocks 15 are all made into inclined surfaces to match the side frame of the female mold 14. The middle position of the top of the male mold ballast core block 16 can extend into the conical positioning groove of the female mold 14. Under the restriction of the side frame of the female mold 14, multiple male mold side pressure blocks 15 provide lateral pressure to the male mold ballast core block 16 to act on the preform 10 to reach the set pressure, and pressurize to discharge the internal pores of the material. In the initial state of the hot-pressing combined mold, multiple male mold side pressure blocks 15 are in an expanded state under the action of the compression spring 17, and the interval between them and the male mold ballast core block 16 is relatively large to adapt to the loose positioning of the preform 10. During the mold closing process, the male mold ballast core block 16 gradually moves toward the inner side of the female mold 14. Under the restriction of the side frame, multiple male mold side pressure blocks 15 gradually compress the compression spring 17 and move slightly toward the male mold ballast core block 16 until the middle position of the top of the male mold ballast core block 16 extends into the conical positioning groove of the female mold 14 to complete the mold closing. The concave configuration of the female mold 14 and the top of the male mold ballast core block 16 and multiple male mold side pressure blocks 15 provide pressure to the flange rib 01 and the base flange 03 of the preform 10. At the same time, the male mold ballast core block 16 and multiple male mold side pressure blocks 15 provide pressure to the vertical flange 02 of the preform 10. Each load-bearing surface of the preform 10 is pressurized to reach the set pressure to discharge the pores.

[0063] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other forms of assembly without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-restrictive, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations within the meaning and range of equivalents of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0064] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A thermoplastic composite T-shaped window frame structure, characterized in that: The invention relates to a runway elliptical window frame consisting of a flange rib (01), a vertical flange (02) and a base flange (03). The cross section of the runway elliptical window frame is an inverted T-shaped structure. The window frame base is spliced ​​by a Z-shaped cross-section preformed component at the bottom and an L-shaped cross-section preformed component No. Ⅰ and an L-shaped cross-section preformed component No. Ⅱ at the top. A unidirectional prepreg ply (04) is laid and wound in the splicing gap of the window frame base to form a preformed body (10), which is then cured by hot pressing. The overlapping part of the L-shaped cross-section preformed component No. Ⅰ and the L-shaped cross-section preformed component No. Ⅱ is the middle vertical section of the inverted T-shaped structure and forms the vertical flange (02). The overlapping part of the L-shaped cross-section preformed component No. Ⅰ and the Z-shaped cross-section preformed component is the inner horizontal section of the inverted T-shaped structure and forms the flange rib (01). The overlapping part of the L-shaped cross-section preformed component No. Ⅱ and the Z-shaped cross-section preformed component is the outer horizontal section of the inverted T-shaped structure and forms the base flange (03).

2. A thermoplastic composite T-shaped window frame structure according to claim 1, characterized in that: The No. Ⅰ L-shaped section preformed component is composed of multiple sections of No. Ⅰ L-shaped section preformed parts (08-1) spliced ​​in a circumferential direction, the No. Ⅱ L-shaped section preformed component is composed of multiple sections of No. Ⅱ L-shaped section preformed parts (08-2) spliced ​​in a circumferential direction, and the Z-shaped section preformed component is composed of multiple sections of Z-shaped section preformed parts (08-3) spliced ​​in a circumferential direction, and after being spliced ​​into a window frame base, each joint (08-4) is staggered. The raw materials of the No. Ⅰ L-shaped section preformed parts (08-1), the No. Ⅱ L-shaped section preformed parts (08-2) and the Z-shaped section preformed parts (08-3) are all cut from the same thermoplastic composite laminated flat plate (05) and are respectively pressed by corresponding block hot pressing molding tools (07).

3. A thermoplastic composite T-shaped window frame structure according to claim 2, characterized in that: During the cutting process of the thermoplastic composite laminated plate (05), the laminated plate cutting edge (05-1) and the laminated plate fiber angle (05-2) are kept parallel.

4. A compression molding process for a thermoplastic composite T-shaped window frame structure, characterized in that: According to the T-shaped window frame structure of claim 3, the molding process thereof comprises the following steps: Step 1: Cutting Using the same thermoplastic composite laminated flat plate (05), cutting and blanking are performed according to the number and unfolded size of the No. Ⅰ L-shaped section preformed sub-piece (08-1), the No. Ⅱ L-shaped section preformed sub-piece (08-2) and the Z-shaped section preformed sub-piece (08-3) required for the runway elliptical window frame segmentation, and the blanking size ensures that margins are left at the edges, thereby obtaining a plurality of flat plate units to be processed; Step 2: Hot pressing of blocks The plurality of plate units to be processed are respectively pressed into a plurality of sections of L-shaped section preformed parts (08-1), L-shaped section preformed parts (08-2) and Z-shaped section preformed parts (08-3) by corresponding block hot pressing forming tools (07), wherein the forming angle (06) of the block hot pressing forming tools (07) is designed as required according to the angles of the L-shaped section preformed parts (08-1), L-shaped section preformed parts (08-2) and Z-shaped section preformed parts (08-3); Step 3: Machining The multi-section No. Ⅰ L-section preformed parts (08-1), No. Ⅱ L-section preformed parts (08-2) and Z-section preformed parts (08-3) after hot pressing are machined and reshaped according to the net size, and the margins at the edges are removed; Step 4: Combined winding The multi-segment No. Ⅰ L-section preformed parts (08-1), No. Ⅱ L-section preformed parts (08-2) and Z-section preformed parts (08-3) of the machined type with completed net size are respectively spliced ​​in a circular manner to form No. Ⅰ L-section preformed components, No. Ⅱ L-section preformed components and Z-section preformed components, and then the No. Ⅰ L-section preformed components and No. Ⅱ L-section preformed components are set and placed on the top of the Z-section preformed components to form a window frame matrix, and at the same time, a unidirectional prepreg layer (04) is laid in the splicing gap of the window frame matrix to form a preformed body (10), thereby completing the preparation of the preformed body (10); Step 5: Preform Heating The prepared preform (10) is heated in an oven or placed in a hot pressing combined mold and heated by conduction through the mold, wherein the heating temperature is within a range from room temperature to 400° C. and is adjusted according to the material of the thermoplastic composite laminated plate; Step 6: Hot Pressing of Components After the preform (10) is heated, it is molded together with a hot pressing combined mold to prepare a runway oval window frame, wherein the hot pressing combined mold comprises a male mold and a female mold (14), and the combined mold cavity (19) after the hot pressing combined mold is molded together has the same configuration as the runway oval window frame, and a lateral pressure of not less than 2MPa can be applied to the runway oval window frame during the mold closing process; Step 7: Cooling and demoulding machine The hot-pressed runway elliptical window frame is separated from the hot-pressing combined mold, cooled naturally at room temperature, and the shape is trimmed according to the design dimensions of the window frame structure by digital modeling.

5. The compression molding process of a thermoplastic composite T-shaped window frame structure according to claim 4, characterized in that: The male mold of the hot-pressing combined mold comprises a bottom mold (12), a male mold ballast core block (16) and a plurality of male mold side pressure blocks (15); the recessed configuration of the female mold (14) matches the bottom of the runway elliptical window frame and a conical positioning groove is added in the center; the edge of the female mold (14) is integrally provided with a side frame with an inclined inner wall around the recessed configuration; the male mold ballast core block (16) is fixed at the center position of the bottom mold (12) surface; a plurality of male mold side pressure blocks (15) are arranged around the male mold ballast core block (16); the plurality of male mold side pressure blocks (15) are slidably combined with the bottom mold (12) respectively via connecting slideways (18); the inner bottoms of the plurality of male mold side pressure blocks (15) are processed and arranged at positions corresponding to the male mold ballast core block (16) The mounting holes (20) are connected and assembled respectively by compression springs (17); a limit platform (13) is formed on the surface of the male mold ballast core block (16) and the plurality of male mold side pressure blocks (15); the limit platform (13) is configured to match the top of the runway elliptical window frame; a combined model cavity (19) is formed between the female mold (14), the male mold ballast core block (16) and the plurality of male mold side pressure blocks (15); the outer sides of the plurality of male mold side pressure blocks (15) are all made into inclined surfaces to match the side frame of the female mold (14); the middle position of the top of the male mold ballast core block (16) can extend into the conical positioning groove of the female mold (14); and under the restriction of the side frame of the female mold (14), the plurality of male mold side pressure blocks (15) provide lateral pressure to the male mold ballast core block (16).

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