Composite material square box constant-force curing pressurizing device and method

Abstract

According to the constant-force curing and pressurizing device and method for the composite square box, compared with a winding cloth bag pressurizing and curing mode, the problem that the four faces of the composite square box protrude outwards is solved, and the quality of a product is improved; compared with rigid plate pressurization curing, the pressure can be kept constant and uniform when the composite material square box is cured, and the curing process stability and the curing quality are ensured. The whole curing and pressurizing device is convenient and fast in structure and easy to operate, provides an effective and feasible solution for curing and pressurizing of the composite square box, and is suitable for large-scale industrial use and popularization.

Description

Technical Field

[0001] The invention belongs to the field of composite material structure manufacturing, and in particular relates to a composite material square box constant force curing pressurizing device and method. Background Art

[0002] During the curing process, resin-based composite products need to be fully pressurized. Existing curing pressurization technologies mainly include gas pressurization, wrapping bag pressurization, rigid plate pressurization, etc.

[0003] Among them, gas pressurization is generally carried out in an autoclave, and there is no special requirement for the shape of the product, but it is only suitable for dry-wound products.

[0004] Wrapping cloth bag pressurization and rigid plate pressurization are suitable for wet-wound products. For composite material boxes with square cross-sections, when the wrapping cloth bag pressurization method is used for curing, bulges appear on all four sides of the square composite material tube. The reason is that for products with square cross-sections, the force applied by the cloth bag wrapped on any one side is a plate beam with two edges fixed, and it is a flexible plate beam. In this way, the air pressure formed by the volatile components of the composite material during the curing process acts on the above-mentioned flexible cloth bag plate beam, forming an outward deflection, resulting in a bulge.

[0005] When using a rigid plate for pressurization, the rigid plate is usually loose after curing, resulting in insufficient curing pressure and poor curing effect. One reason is that the surface roughness of the composite material box is large, and the other is that the matrix resin will flow when the composite material is cured and heated, which causes the rigid pressurization plate to be pressed tightly before curing. After curing, it will move as the resin flows, resulting in a gap between the rigid plate and the composite material box, causing it to loosen.

[0006] In summary, the current wrapping bag pressurization method and rigid plate pressurization are not suitable for square composite tube curing pressurization, and new solutions need to be explored. Summary of the invention

[0007] The object of the present invention is to provide a composite material square box constant force curing pressurizing device and method, so as to solve the problem that the pressurizing method in the prior art is not suitable for square composite material tubes.

[0008] In order to solve the above technical problems, the present invention adopts the following technical solutions to achieve the above problems:

[0009] A composite material square box constant force curing pressurizing device, comprising a winding mandrel, on which a composite material square box formed by winding is arranged, and further comprising an L-shaped back plate, two flat pressing plates of the same shape and a plurality of square hoop frames;

[0010] The L-shaped back plate covers two adjacent side walls of the composite material square box, and the two flat pressing plates cover the other two side walls of the composite material square box respectively;

[0011] The plurality of square hoop frames are evenly distributed along the length direction of the composite material square box; the adjacent two side walls of the square hoop frames are fitted with the L-shaped back plate as fixed sides, and the other two side walls are spaced apart from the two flat pressing plates as pressurizing sides;

[0012] A plurality of threaded holes are provided on both side walls of the pressurizing side of each of the square hoop frames, and a pressure rod corresponding to each threaded hole is provided on the flat pressure plate;

[0013] An adjusting nut is rotatably arranged inside the threaded hole, the upper part of the pressure rod enters the inner ring of the adjusting nut, and the matching mode between the upper part of the pressure rod and the inner ring of the adjusting nut is a clearance fit;

[0014] The pressure rod is sleeved with a compression spring; the adjusting nut can adjust the compression degree of the corresponding compression spring by rotating in the threaded hole, thereby applying a torque to the flat pressure plate.

[0015] The present invention also has the following features:

[0016] Furthermore, 2-3 through threaded holes are respectively provided on the two side walls of the pressurizing side of each of the square hoop frames.

[0017] Furthermore, the top of the adjusting nut is coaxially and fixedly connected with a hexagonal bolt.

[0018] Furthermore, the L-shaped backboard has an "L"-shaped cross section, wherein the widths of the two sides of the cross section are the same and smaller than the side length of the cross section of the composite material square box;

[0019] The width of the flat pressing plate is smaller than the side length of the cross section of the composite material square box.

[0020] A method for using a composite material square box constant force curing pressurizing device, the method is based on the above composite material square box constant force curing pressurizing device, comprising the following steps:

[0021] Step 1, horizontally setting a composite material square box with a winding core mold;

[0022] Step 2, with the notch of the L-shaped back plate facing downward, place the L-shaped back plate on the composite material square box;

[0023] Step 3, sequentially set two flat pressing plates, set all square hoop frames at corresponding positions of the composite material square box, and apply torque to the two flat pressing plates according to actual design torque requirements;

[0024] Step 4, curing the composite material square box constant force curing pressurizing device as a whole until the curing is completed.

[0025] Further, in step 3, applying a torque to the flat plate includes the following method:

[0026] Method 1: Apply torque to the two flat pressure plates in sequence; when applying torque, gradually apply tightening torque to all nuts for multiple times until the torque applied to the flat pressure plates reaches the design torque requirement;

[0027] Method 2: Apply torque to the two flat pressure plates in sequence. When applying torque, apply tightening torque to all nuts from both ends to the middle in sequence. Each time the tightening torque is applied, the torque applied to the flat pressure plates reaches the design torque requirement.

[0028] Method 3, applying torque to two flat pressure plates at the same time, and when applying torque, gradually applying tightening torque to all nuts for multiple times until the torque applied to the flat pressure plates reaches the design torque requirement.

[0029] Furthermore, in step 3, the posture of the planar pressing plate is adjusted when a torque is applied to the planar pressing plate to prevent the planar pressing plate from tilting.

[0030] Compared with the prior art, the present invention has the following technical effects:

[0031] Compared with the method of wrapping cloth bags and pressurizing and curing, the constant force curing and pressurizing device and method of the composite material square box of the present invention avoids the problem of the four surfaces of the composite material square box bulging outward, and improves the quality of the product; compared with the pressurizing and curing of rigid plates, the present invention can keep the pressure of the composite material square box constant and uniform during curing, ensuring the stability of the curing process and the curing quality. The overall curing and pressurizing device has a convenient structure and is easy to operate. It also provides an effective and feasible solution for the curing and pressurizing of composite material square boxes, and is suitable for large-scale use and promotion in industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of the overall structure of the composite material square box constant force curing pressurizing device of the present invention;

[0033] Figure 2 It is a partial enlarged view of the composite material square box constant force curing pressurizing device of the present invention;

[0034] Figure 3 It is a schematic diagram of the connection relationship between the composite material square box and the winding core mold in the present invention;

[0035] Figure 4 It is a schematic diagram of the L-shaped back panel structure in the present invention;

[0036] Figure 5 It is a schematic diagram of the flat pressing plate structure in the present invention;

[0037] Figure 6 It is a schematic diagram of the square hoop frame structure in the present invention;

[0038] Figure 7 It is a schematic diagram of the structure of the adjusting nut in the present invention;

[0039] Figure 8 It is a schematic diagram of the compression rod structure in the present invention.

[0040] The meaning of the symbols in the figure is:

[0041] 1. Winding core mold; 2. Composite material square box; 3. Square hoop frame; 4. L-shaped back plate; 5. Flat pressure plate; 6. Threaded hole; 7. Pressure rod; 8. Adjustment nut; 9. Compression spring; 10. Hexagonal bolt. DETAILED DESCRIPTION

[0042] It should be noted that, unless otherwise specified, all components in the present invention are components known in the prior art. For example, the composite material square box is a known and commonly used composite material square box.

[0043] Specific embodiments of the present invention are given below. It should be noted that the present invention is not limited to the following specific embodiments, and all equivalent changes made on the basis of the technical solution of this application fall within the protection scope of the present invention.

[0044] like Figure 1-6 As shown, a composite material square box constant force curing pressurizing device comprises a winding mandrel 1, on which a composite material square box 2 formed by winding is arranged, characterized in that it also comprises an L-shaped back plate 4, two flat pressing plates 5 of the same shape and a plurality of square hoop frames 3;

[0045] The L-shaped back plate 4 covers two adjacent side walls of the composite material square box 2, and two flat pressing plates 5 cover the other two side walls of the composite material square box 2 respectively;

[0046] A plurality of square hoop frames 3 are evenly distributed along the length direction of the composite material square box 2; the adjacent two side walls of the square hoop frames 3 are fitted with the L-shaped back plate 4 as fixed sides, and the other two side walls are spaced apart from the two flat pressing plates 5 as pressurizing sides;

[0047] A plurality of threaded holes 6 are respectively provided on the two side walls of the pressurizing side of each square hoop frame 3, and a pressing rod 7 corresponding to each threaded hole 6 is provided on the flat pressing plate 5;

[0048] An adjusting nut 8 is rotatably arranged inside the threaded hole 6, the upper part of the pressure rod 7 enters the inner ring of the adjusting nut 8 and the fitting mode between the upper part of the pressure rod 7 and the inner ring of the adjusting nut 8 is a clearance fit, and a compression spring 9 is sleeved on the pressure rod 7; the adjusting nut 8 can adjust the compression degree of the corresponding compression spring by rotating in the threaded hole 6, thereby applying torque to the flat pressure plate 5.

[0049] like Figure 8As shown, the axial cross section of the pressure rod 7 is a "convex" shape, and its length is adapted to the distance between the square hoop frame 3 and the flat pressure plate 5.

[0050] As a preferred solution, two to three through threaded holes 6 are respectively provided on the two side walls of the pressurizing side of each square hoop frame 3 .

[0051] Among them, a square hoop frame 3, 2-3 adjusting nuts 8, 2-3 pressure rods, and 2-3 compression springs 9 constitute a set of pressurizing units.

[0052] The square hoop frame sleeve 3 is outside the L-shaped back plate 4 and the two flat pressure plates 5, contacts the L-shaped back plate 4, forms a certain distance with the two flat pressure plates 5, and the square hoop frame 3 is evenly distributed along the axial direction of the winding core shaft 1; the adjusting nut 8 is respectively connected to the threaded holes 6 corresponding to the square hoop frame 3 through its own external thread; the compression spring 9 is sleeved with the pressure rod 7 one by one, and then installed between the square hoop frame 3 and the flat pressure plate 5 through the center hole of the adjusting nut 8.

[0053] When the device is in use, the pressurized force comes from the compression spring 9, which satisfies Hooke's law F=k*Δx, where F is the spring force, k is the spring coefficient, and Δx is the spring compression amount.

[0054] Δx depends on the distance between the contact end surface of the adjusting nut 8 and the compression spring 9 and the flat pressure plate 5, so the adjusting force F can be achieved by adjusting the tightness of the adjusting nut 8. At the same time, the force F and the preload force of the adjusting nut 8 satisfy a certain functional relationship, thereby indirectly establishing a relationship between the preload force of the adjusting nut 8 and the pressure, and applying the same preload force to each pressurizing unit is equivalent to applying the same pressure to the flat pressure plate through each pressurizing unit.

[0055] In addition, during the pressurized curing process, the flat pressing plate 5 will be displaced, but the displacement is very small, and the resulting reduction in spring force can be ignored, so it is considered that the curing pressure is constant.

[0056] As a preferred solution, a hexagonal bolt 10 is coaxially and fixedly connected to the top of the adjusting nut 8 .

[0057] As a preferred solution, the cross section of the L-shaped backboard is an "L" shape, wherein the widths of the two sides are the same and smaller than the side length of the cross section of the composite material square box 2;

[0058] The width of the flat pressing plate 5 is smaller than the side length of the cross section of the composite material square box 2 .

[0059] A method for using a composite material square box constant force curing pressurizing device, the method is based on the above composite material square box constant force curing pressurizing device, comprising the following steps:

[0060] Step 1, horizontally arranging a composite material square box 2 with a winding core mold 1;

[0061] Step 2, with the notch of the L-shaped back plate 4 facing downward, place the L-shaped back plate 4 on the composite material square box 2;

[0062] Step 3, sequentially set two flat pressing plates 5, set all square hoop frames 3 at corresponding positions of the composite material square box 2, and apply torque to the two flat pressing plates 5 according to actual design torque requirements;

[0063] Step 4, curing the composite material square box constant force curing pressurizing device as a whole until the curing is completed.

[0064] During the curing process, the composite resin matrix will flow at high temperature, and the flat platen 5 will also follow the force of the compression spring 9, thereby ensuring that the flat platen 5 always maintains contact with the composite square box 2 and applies force. At the same time, displacement is generated by following the movement, but this displacement is very small, so the compression amount of the compression spring 9 does not change much, thereby ensuring that the curing pressure of the composite square box 2 remains constant. In summary, no matter how the composite square box 2 deforms, the flat platen 5 always applies constant pressure to it, ensuring a stable curing process.

[0065] Further, in step 3, applying a torque to the flat pressing plate 5 includes the following method:

[0066] Method 1: Apply torque to the two flat pressure plates 5 in sequence; when applying torque, gradually apply tightening torque to all nuts for multiple times until the torque applied to the flat pressure plates 5 reaches the design torque requirement;

[0067] Method 2, applying torque to the two flat pressure plates 5 in sequence, and applying tightening torque to all nuts from both ends to the middle in sequence when applying torque, and each time the tightening torque is applied, the torque applied to the flat pressure plates 5 reaches the design torque requirement;

[0068] Method 3, torque is applied to two planar pressure plates 5 at the same time. When applying the torque, tightening torque is gradually applied to all nuts for multiple times until the torque applied to the planar pressure plates 5 reaches the design torque requirement.

[0069] Furthermore, in step 3, the posture of the planar pressing plate 5 is adjusted when a torque is applied to the planar pressing plate 5 to prevent the planar pressing plate 5 from tilting.

Claims

1. A composite material square box constant force curing pressurizing device, comprising a winding core mold (1), on which a composite material square box (2) formed by winding is arranged, characterized in that: It also includes an L-shaped back plate (4), two flat pressing plates (5) of the same shape and a plurality of square hoop frames (3); The L-shaped back plate (4) covers two adjacent side walls of the composite material square box (2), and the two flat pressing plates (5) respectively cover the other two side walls of the composite material square box (2); The plurality of square hoop frames (3) are evenly distributed along the length direction of the composite material square box (2); the adjacent two side walls of the square hoop frames (3) are fitted with the L-shaped back plate (4) as fixed sides, and the other two side walls are spaced apart from the two flat pressing plates (5) as pressurizing sides; A plurality of threaded holes (6) are provided on both side walls of the pressurizing side of each of the square hoop frames (3), and a pressure rod (7) corresponding to each threaded hole (6) is provided on the flat pressure plate (5); An adjusting nut (8) is rotatably arranged inside the threaded hole (6), the upper part of the pressure rod (7) enters the inner ring of the adjusting nut (8), and the fitting mode between the upper part of the pressure rod (7) and the inner ring of the adjusting nut (8) is a clearance fit; The pressure rod (7) is sleeved with a compression spring (9); the adjusting nut (8) can adjust the compression degree of the corresponding compression spring (9) by rotating in the threaded hole (6), thereby applying a torque to the flat pressure plate (5).

2. The composite material square box constant force curing pressurizing device according to claim 1, characterized in that: Each of the square hoop frames (3) is provided with 2-3 through threaded holes (6) on both side walls on the pressure side.

3. The composite material square box constant force curing pressurizing device according to claim 1, characterized in that: The top of the adjusting nut (8) is coaxially and fixedly connected with a hexagonal bolt (10).

4. The composite material square box constant force curing pressurizing device according to claim 1, characterized in that: The L-shaped backboard (4) has an "L"-shaped cross section, wherein the widths of the two sides of the cross section are the same and smaller than the side length of the cross section of the composite material square box (2); The width of the flat pressing plate (5) is smaller than the side length of the cross section of the composite material square box (2).

5. A method for using a composite material square box constant force curing pressurization device, the method is based on the composite material square box constant force curing pressurization device according to claims 1-4, characterized in that: The following steps are involved: Step 1, horizontally arranging a composite material square box (2) with a winding core mold (1); Step 2, placing the L-shaped back plate (4) with the notch facing downward on the composite material square box (2); Step 3, sequentially arranging two flat pressing plates (5), arranging all the square hoop frames (3) at corresponding positions of the composite material square box (2), and applying torque to the two flat pressing plates (5) according to actual design torque requirements; Step 4, curing the composite material square box constant force curing pressurizing device as a whole until the curing is completed.

6. The method for using the composite material square box constant force curing pressurization device as claimed in claim 5, characterized in that: In step 3, applying a torque to the flat pressing plate (5) includes the following methods: Method 1: applying torque to the two flat pressing plates (5) in sequence; when applying the torque, gradually applying tightening torque to all nuts for multiple times until the torque applied to the flat pressing plates (5) reaches the design torque requirement; Method 2, applying torque to the two flat pressing plates (5) in sequence, and applying tightening torque to all nuts from both ends to the middle in sequence when applying torque, and each time the tightening torque is applied, the torque applied to the flat pressing plates (5) reaches the design torque requirement; Method 3, two planar pressure plates (5) apply torque at the same time, and when applying the torque, tightening torque is gradually applied to all nuts for multiple times until the torque applied to the planar pressure plates (5) reaches the design torque requirement.

7. The method for using the composite material square box constant force curing pressurization device as claimed in claim 5, characterized in that: In step 3, the posture of the planar pressing plate (5) is adjusted when a torque is applied to the planar pressing plate (5) to prevent the planar pressing plate (5) from tilting.

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