Vacuum bag forming device

Abstract

The utility model discloses a vacuum bag forming device which comprises a mold, at least one vacuum bag and a first exhaust channel, the edge of the vacuum bag is connected with the top face of the mold through a bonding part, and the first exhaust channel comprises a first pipeline and a second pipeline which are vertically arranged; the first pipeline is arranged in a sealed space defined by the vacuum bag and the top face of the mold, part of the structure of the bonding part extends towards the side away from the mold to form a protruding structure, and at least part of the protruding structure directly faces the first pipeline in the first direction. In the application, the part of the structure of the bonding part extends towards one side deviating from the mold to form the convex structure, and the convex structure can jack up part of the surface of the vacuum bag, so that the position, close to the first exhaust pipeline, of the vacuum bag is prevented from being torn when negative pressure is pumped from the sealed space through the first exhaust pipeline, and the preparation success rate is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of composite material forming devices, and in particular to a vacuum bag forming device. BACKGROUND

[0002] Resin-based composite materials have the characteristics of high strength and light weight, and are thus applied in the industries of aviation, automobiles, oceans, etc. The vacuum assisted forming process has the advantages of simplicity, high efficiency and low cost, and the formed products have certain mechanical properties and are thus widely applied.

[0003] In the related art, resin-based composite material structures are usually prepared using the vacuum bag forming process, but the vacuum bag is prone to damage under negative pressure, leading to preparation failure and increased cost. CONTENT OF THE INVENTION

[0004] To overcome the problems in the related art, the present application provides a vacuum bag forming device.

[0005] According to an embodiment of the present application, a prepreg forming device is provided, comprising:

[0006] a mold;

[0007] at least one vacuum bag, the edge of the vacuum bag being connected to the top surface of the mold through an adhesive portion, and the vacuum bag and the top surface of the mold enclosing a sealed space;

[0008] a first air extraction channel comprising a first pipeline and a second pipeline, the first pipeline being arranged in the sealed space and extending along a first direction, and the second pipeline being connected to the first pipeline and a first negative pressure device and extending along a second direction, the first direction being perpendicular to the second direction;

[0009] wherein part of the structure of the adhesive portion extends to form a protruding structure away from the mold, and at least part of the protruding structure is directly opposite the first pipeline along the first direction.

[0010] In some embodiments, along the first direction, the protruding structure is arranged on both sides of the first pipeline.

[0011] In some embodiments, the first pipeline is a spiral pipeline.

[0012] In some embodiments, the at least one vacuum bag comprises:

[0013] an inner vacuum bag, the inner vacuum bag and part of the top surface of the mold enclosing a first space, and a preform being arranged in the first space;

[0014] an outer vacuum bag, the outer vacuum bag, the inner vacuum bag and part of the top surface of the mold enclosing a second space.

[0015] In some embodiments, the prepreg molding device further comprises a second air extraction channel, which is communicated with a second negative pressure device and the second space.

[0016] In some embodiments, the protruding structure comprises a first protruding structure formed by the bonding part for bonding the outer vacuum bag and the mold;

[0017] In the first direction, at least part of the first protruding structure is opposite to the second air extraction channel.

[0018] In some embodiments, the prepreg molding device further comprises a feeding channel, which comprises:

[0019] A third pipeline is arranged in the first space and extends in the first direction;

[0020] A fourth pipeline is connected with the third pipeline and extends in the second direction, and the fourth pipeline is used for connecting the third pipeline and a storage device.

[0021] In some embodiments, the first pipeline and the second pipeline are connected by a tee joint; and / or,

[0022] The third pipeline and the fourth pipeline are connected by a tee joint.

[0023] In some embodiments, in the first direction, part of the protruding structure is opposite to the third pipeline.

[0024] In some embodiments, the prepreg molding device further comprises:

[0025] A release cloth is arranged in the sealed space, and the release cloth covers the prepreg on the mold;

[0026] A flow guide net is arranged in the sealed space and on the side of the release cloth opposite to the prepreg;

[0027] In the second direction, the size of the flow guide net is 45% to 55% of the size of the release cloth.

[0028] The technical scheme provided by the embodiments of the present application can have the following beneficial effects: by extending part of the structure of the bonding part towards the side away from the mold to form a protruding structure, the protruding structure can lift part of the surface of the vacuum bag, so that the position of the vacuum bag close to the first air extraction pipeline is not torn when the sealed space is extracted by the first air extraction pipeline, and the success rate of preparation is improved.

[0029] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application, as claimed. BRIEF DESCRIPTION OF DRAWINGS

[0030] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the application and serve to explain the principles of the application, in which:

[0031] Figure 1 A schematic diagram of a vacuum bag forming device provided by an embodiment of the application is shown;

[0032] Figure 2 is Figure 1 A cross-sectional view in the A-A direction of FIG. 1.

[0033] In the drawings:

[0034] 100, forming device;

[0035] 10, mold;

[0036] 20, bonding portion; 20a, outer ring high-temperature adhesive tape; 20b, inner ring high-temperature adhesive tape; 21, protruding structure; 21a, first protruding structure; 21b, second protruding structure; 22, reinforcing structure;

[0037] 30, first air extraction channel; 31, first pipe; 32, second pipe;

[0038] 40, second air extraction channel;

[0039] 50, feeding channel; 51, third pipe; 52, fourth pipe;

[0040] 60, release cloth;

[0041] 70, flow guide net;

[0042] 80, three-way connector;

[0043] 200, preform. DETAILED DESCRIPTION

[0044] The exemplary embodiments will be described in detail herein with reference to the attached drawings. The description of the exemplary embodiments is intended to apply to all alternative embodiments, as would be understood by one skilled in the art. The following exemplary embodiments are described in enough detail to enable those skilled in the art to make and use the application, and it will be apparent that structures, systems, and methods that are similar to the exemplary embodiments already described can be used in conjunction with the exemplary embodiments. Such structures, systems, and methods need not be described in detail herein. The following detailed description is, therefore, not to be taken in a limiting sense, as the scope of the application is defined by the appended claims.

[0045] To solve the above technical problems, the present application provides a vacuum bag molding device, which comprises a mold, at least one vacuum bag and a first exhaust passage, the edge of the vacuum bag is connected to the top of the mold through an adhesive part, the first exhaust passage comprises a first pipeline and a second pipeline arranged vertically, the first pipeline is arranged in a sealed space formed by the vacuum bag and the top surface of the mold, part of the structure of the adhesive part extends to the side away from the mold to form a protruding structure, and at least part of the protruding structure is opposite to the first pipeline in a first direction. In the present application, part of the structure of the adhesive part extends to the side away from the mold to form a protruding structure, the protruding structure can lift part of the surface of the vacuum bag to avoid the position of the vacuum bag close to the first exhaust pipeline being torn when the sealed space is exhausted by the first exhaust pipeline, thereby improving the success rate of preparation.

[0046] According to an exemplary embodiment of the present application, as shown in Figure 1 and Figure 2 , the present embodiment provides a vacuum bag molding device 100, which can make the preform 200 cured and formed under vacuum pressure by a vacuum method.

[0047] As shown in Figure 1 , the vacuum bag molding device 100 comprises a mold 10, at least one vacuum bag (not shown in the figure) and a first exhaust passage 30, the top surface of the mold 10 is used to place the preform 200, the vacuum bag and the first exhaust passage 30 are arranged on the top surface of the mold 10, the edge of the vacuum bag is connected to the mold 10 through an adhesive part, so that the vacuum bag can define a sealed space with the top surface of the mold 10, the preform 200 is placed in the sealed space, the first exhaust passage 30 is connected to the first negative pressure device (not shown in the figure, such as a vacuum pump) and the sealed space, the first negative pressure device can exhaust the gas in the sealed space through the first exhaust passage 30, so that the sealed space is in a negative pressure (vacuum) state, and the preform 200 can be cured and formed under the action of negative pressure.

[0048] As shown in Figure 1 , the first exhaust passage 30 comprises a first pipeline 31 and a second pipeline 32, the first pipeline 31 is arranged in the sealed space and extends in a first direction (y direction shown in Figure 1 , the second pipeline 32 is used to connect the first negative pressure device and the first pipeline 31, and the second pipeline 32 extends in a second direction (x direction shown in Figure 1 , and the first direction is perpendicular to the second direction. Referring to Figure 1 , it can be determined that the length of the first pipeline 31 is similar to the width of the preform 200, and by arranging the first pipeline 31, the resin on the left side of the sealed space can be balanced to ensure that the resin is fully immersed in each area of the preform 200.

[0049] Referring to Figure 1In this embodiment, the edge of the vacuum bag is bonded to the top surface of the mold 10 via an adhesive part 20, and a portion of the structure of the adhesive part 20 extends toward the side away from the mold 10 to form a protruding structure 21, along the extending direction of the first pipeline 31. Figure 1 As shown in the y-direction, at least a portion of the protruding structure 21 is directly opposite the first conduit 31. It is understood that the protruding structure 21 raises a portion of the vacuum bag's height, thereby preventing the vacuum bag from being adsorbed onto the surface of the first conduit 31 when gas is drawn from the sealed space through the first conduit 31, thus avoiding damage to the vacuum bag due to suction.

[0050] In one example, see Figure 1 The adhesive portion 20 is strip-shaped, and a portion of the adhesive portion 20 can be bent to form a raised structure 21. Directly bending the adhesive portion 20 can result in lower costs.

[0051] In another example (not shown in the figures), a protrusion can be provided at the location of the adhesive portion used to form the raised structure, and the adhesive portion can be used to cover the protrusion to form the raised structure. By setting the adhesive portion to cover the protrusion, it is easier to control the size of multiple raised structures, ensure the shape consistency of multiple raised structures, and achieve faster assembly and forming efficiency of the molding device.

[0052] In this embodiment, a protruding structure is formed by extending a portion of the adhesive part toward the side away from the mold. The protruding structure can lift a portion of the surface of the vacuum bag to prevent the part of the vacuum bag near the first suction pipe from being torn when negative pressure is drawn into the sealed space through the first suction pipe, thereby improving the success rate of preparation.

[0053] In one exemplary embodiment, such as Figure 1 As shown, the vacuum bag forming device includes a mold, at least one vacuum bag, and a first exhaust channel. The edge of the vacuum bag is connected to the top of the mold through an adhesive part. The first exhaust channel includes a first pipe and a second pipe arranged vertically. The first pipe is disposed in the sealed space formed by the vacuum bag and the top surface of the mold. A portion of the adhesive part extends toward the side away from the mold to form a protruding structure. At least a portion of the protruding structure is directly opposite the first pipe along a first direction.

[0054] Among them, such as Figure 1 As shown, along the first direction ( Figure 1 As shown in the y-direction), protruding structures 21 are provided on both sides of the first pipe 31. It should be noted that when the vacuum bag forming device 100 provides multiple (e.g., two) vacuum bags, the protruding structure 21 (second protruding structure 21) connected to the innermost vacuum bag (inner vacuum bag, detailed later) can be positioned directly opposite the first pipe 31, or all protruding structures 21 connected to all vacuum bags can be positioned directly opposite the first pipe 31 (see [reference]).Figure 1 ), but not limited. In this embodiment, the two sides of the vacuum bag are lifted to form a tent shape by setting the protruding structure 21 on both ends of the first pipeline 31, so as to be separated from the whole first pipeline 31.

[0055] As shown in Figure 1 , the first pipeline 31 can be a spiral pipe. The spiral pipe has higher structural strength, and the surface of the spiral pipe has a larger contact area with the sealed space, which is beneficial to setting the air extraction hole to improve the air extraction efficiency. In one example, referring to Figure 1 , the first pipeline 31 can be communicated with the second pipeline 32 through the three-way connector 80.

[0056] As shown in Figure 1 , the vacuum bag forming device 100 includes two vacuum bags, i.e. an inner vacuum bag and an outer vacuum bag. Referring to Figure 1 , the inner vacuum bag and part of the surface of the mold 10 form a first space, and the first pipeline 31 of the first air extraction channel 30 and the preform 200 are arranged in the first space. In one example, the size of the inner vacuum bag is about 500mm×500mm.

[0057] Referring to Figure 1 , the surface area of the outer vacuum bag is larger than that of the inner vacuum bag. The bonding part 20 connected to the outer vacuum bag is located on the side away from the first space of the bonding part 20 connected to the inner vacuum bag, so that the outer vacuum bag, the inner vacuum bag and part of the top surface of the mold 10 form a second space. In one example, the size of the outer vacuum bag is about 520mm×520mm, and the geometric centers of the outer vacuum bag and the inner vacuum bag are arranged coincidentally, so that there is a 10mm spacing between the bonding part 20 connected to the outer vacuum bag and the bonding part 20 connected to the inner vacuum bag. In this embodiment, by arranging a layer of outer vacuum bag on the outer layer of the inner vacuum bag of the vacuum bag forming device 100, and forming a sealed second space between the outer vacuum bag and the inner vacuum bag, it can be determined that when the inner vacuum bag is damaged, if the second vacuum bag is not damaged, the sealed space is still in a sealed state, thereby improving the reliability of the vacuum bag forming device 100 and facilitating the improvement of the preparation success rate.

[0058] As shown in Figure 1 , the vacuum bag forming device 100 further includes a second air extraction channel 40, and the second air extraction channel 40 communicates the second negative pressure device with the second space. The second negative pressure device is, for example, a vacuum pump. The second negative pressure device can extract negative pressure from the second space through the second air extraction channel 40. The second negative pressure device can be the same vacuum pump as the first negative pressure device, or can be two independent vacuum pumps. In this embodiment, it is not limited too much, as long as the first negative pressure device and the second negative pressure device can extract air from the first space and the second space to have the same mold cavity pressure, for example, -0.1MPa.

[0059] Among them, such as Figure 1 As shown, the protruding structure 21 includes a first protruding structure 21a and a second protruding structure 21b. The first protruding structure 21a is formed by an outer ring high-temperature adhesive tape 20a for bonding the outer vacuum bag to the mold 10, and the second protruding structure 21b is formed by an inner ring high-temperature adhesive tape 20b for bonding the inner vacuum bag to the mold. A portion of the first protruding structure 21a is along a first direction (…). Figure 1 The first protrusion 21 (in the y-direction shown) is directly opposite the second suction channel 40, that is, the first protrusion 21 and the second suction channel 40 are about Figure 1 The AA section lines shown are symmetrically arranged. Figure 1 Taking the orientation shown as an example, this setting can make the outer vacuum bag symmetrical, thereby ensuring that the inner vacuum bag and the outer vacuum bag fit symmetrically, so that the resin in the first space is subjected to balanced force, which is conducive to the resin fully impregnating the preform 200 and improving the quality of the prepared product.

[0060] Among them, such as Figure 1 As shown, the vacuum bag forming apparatus 100 also includes a feeding channel 50, which includes a third pipe 51 and a fourth pipe 52. The third pipe 51 is disposed in the first space and runs along a first direction. Figure 1 Extending in the y-direction shown, the fourth pipe 52 connects the third pipe 51 to the storage device (for storing resin), and the fourth pipe 52 extends along the second direction (as shown in the y-direction). Figure 1 (Extended in the x direction as shown). In one example, the third pipe 51 can be connected to the fourth pipe 52 via a tee connector 80. In this embodiment, by providing the third pipe 51 in the feed channel 50, the length of the third pipe 51 is similar to that of the preform 200, thereby enabling the resin to be fully spread throughout the preform 200, ensuring that the resin is fully immersed in the preform 200.

[0061] Among them, such as Figure 1 As shown, along the first direction ( Figure 1 (As shown in the y-direction), part of the protruding structure 21 is directly opposite the third pipe 51. It can be understood that the protruding structure 21 directly opposite the third pipe 51 can lift part of the surface of the vacuum bag, so that a gap is formed between the vacuum bag and the third pipe 51, in order to avoid the vacuum bag blocking the third pipe 51 and affecting the feeding speed, and to avoid the vacuum bag and the third pipe 51 being torn apart during the evacuation process.

[0062] Among them, such as Figure 1As shown, a release cloth 60 is also provided in the sealed space (first space) of the vacuum bag forming device 100. The release cloth 60 covers the entire top surface of the preform 200 above the mold 10 to prevent the preform 200 and resin from sticking to the vacuum bag, facilitating separation after forming. In one example, the release cloth 60 is square, and each side of the release cloth 60 is about 10mm longer than the preform. For example, if the length and width of the preform are 460mm × 440mm, then the length and width of the release cloth 60 can be 480mm × 440mm.

[0063] See Figure 1 The vacuum bag forming apparatus 100 also includes a flow guide net 70, which is disposed on the side of the release cloth 60 opposite to the preform and near the feed channel 50. The resin has higher fluidity in the flow guide net 70. By setting the flow guide net 70, the resin can flow rapidly in the second direction, which helps to increase the speed at which the resin penetrates the preform, thereby accelerating the forming speed. See also [example description missing]. Figure 1 In the second direction ( Figure 1 In the x-direction shown, the size of the flow guide net 70 is approximately 45% to 55% of the size of the release cloth 60. For example, the flow guide net 70 can be set to be half the size of the release cloth 60. This setting allows the resin to flow rapidly along the second direction for a certain distance and then along the depth direction of the preform. Figure 2 As shown in the z-direction, the resin is immersed into the preform. Compared with the guide net 70 that covers the entire surface of the release cloth 60, it can prevent the resin from existing only on the surface of the preform, ensure the degree of resin penetration along the thickness direction of the preform, and improve product quality.

[0064] The molding apparatus provided in this embodiment can be manufactured using the following method:

[0065] First, provide a mold and apply a release agent evenly to the top surface of the mold. Let it stand for a period of time until the release agent dries. Place the preform in the middle area of ​​the top surface of the mold, and then stack the release cloth and guide net on the surface of the preform in sequence.

[0066] Next, assemble the first suction channel and the feeding channel. The first suction channel can be composed of a first pipe, a second pipe, and a tee connector, while the feeding channel can be composed of a third pipe, a fourth pipe, and a tee connector. It should be noted that PTFE tape needs to be wrapped around the points where the first, second, third, and fourth pipes connect to the tee connectors to ensure reliable connection and sealing.

[0067] Next, use high-temperature tape to adhere the release fabric around its perimeter, forming two "U" shapes. The inner ring of high-temperature tape 20b adheres to the release fabric. ​ A 10mm gap is reserved in the y-direction shown in the diagram, and ​The x direction shown in the middle leaves a 20mm gap, and the upper and lower and left and right edges of the outer ring adhesive tape and the inner ring adhesive tape are all reserved with a 10mm gap.

[0068] Then, the inner ring high-temperature adhesive tape 20b and the outer ring high-temperature adhesive tape 20a are processed to form a reinforcing structure 22 (see ​ and ​ ) at the position of the bonding part opposite to the second pipeline and the fourth pipeline, and the reinforcing structure has a through hole, and the second pipeline and the fourth pipeline pass through the through hole.

[0069] Then, the inner ring high-temperature adhesive tape 20b and the outer ring high-temperature adhesive tape 20a are processed (for example, the adhesive tapes are folded) to form a protruding structure at the position of the high-temperature adhesive tape opposite to the first pipeline and the third pipeline.

[0070] Finally, the edge of the inner vacuum bag is aligned with and bonded to the inner ring high-temperature adhesive tape 20b, and the air tightness of the inner vacuum bag is detected. After the air tightness detection is qualified, the edge of the outer vacuum bag is aligned with and bonded to the outer ring high-temperature adhesive tape 20a, and the air tightness of the outer vacuum bag is detected. In an example, the air tightness can be detected in the following manner: the sealed space is drawn to -0.1 MPa by using the first negative pressure device or the second negative pressure device, and lasts for 10 minutes. The vacuum bag (especially the reinforcing structure and the protruding structure) is continuously pressed during the air drawing. The first negative pressure device and the second negative pressure device are closed to form a seal of the sealed space. After about 24 hours, if the cavity pressure is unchanged, it indicates that the air tightness is qualified.

[0071] The molding device provided by the embodiments of the present application can have the following use method:

[0072] First, the first negative pressure device and the second negative pressure device are controlled to reduce the cavity pressure of the first space and the second space to -0.1 MPa.

[0073] Then, the first negative pressure device and the second negative pressure device are controlled to reduce the cavity pressure of the first space and the second space to -0.1 MPa.

[0074] Then, the feeding channel and the first air drawing channel are closed, the second air drawing channel is kept open, and the resin is cured. The resin is, for example, a liquid molding epoxy resin, and the curing temperature is about 180°C, and the curing duration is about 2 hours.

[0075] Other embodiments of the application will be apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. It is intended that the specification and examples be considered as exemplary only, with the true scope and spirit of the application being indicated by the following claims.

[0076] It is to be understood that the application is not limited to the precise construction herein described and as shown in the drawings, and that various modifications and changes can be made by those skilled in the art without departing from the scope thereof. The scope of the application is limited only by the claims appended hereto.

Claims

1. A vacuum bag forming apparatus, characterized by, The vacuum bag forming device comprises: a mold; at least one vacuum bag, the edge of the vacuum bag is connected with the top surface of the mold through an adhesive part, and the vacuum bag and the top surface of the mold form a sealed space; a first air extraction channel, comprising a first pipeline and a second pipeline, the first pipeline is arranged in the sealed space and extends along a first direction, and the second pipeline is connected with the first pipeline and a first negative pressure device and extends along a second direction, the first direction is perpendicular to the second direction; wherein part of the structure of the adhesive part extends to form a protruding structure away from the mold, and at least part of the protruding structure is opposite to the first pipeline along the first direction.

2. The vacuum bag molding apparatus of claim 1, wherein, Along the first direction, the protruding structure is arranged on both sides of the first pipeline.

3. The vacuum bag molding apparatus of claim 2, wherein, The first pipeline is a spiral pipeline.

4. The vacuum bag molding apparatus of claim 1, wherein, At least one of the vacuum bags comprises: an inner vacuum bag, the inner vacuum bag and part of the top surface of the mold form a first space, and a preform is arranged in the first space; an outer vacuum bag, the outer vacuum bag, the inner vacuum bag and part of the top surface of the mold form a second space.

5. The vacuum bag molding apparatus of claim 4, wherein, The vacuum bag forming device further comprises a second air extraction channel, the second air extraction channel is connected with a second negative pressure device and the second space.

6. The vacuum bag molding apparatus of claim 5, wherein, The protruding structure comprises a first protruding structure, the first protruding structure is formed by the adhesive part for bonding the outer vacuum bag and the mold; Along the first direction, at least part of the first protruding structure is opposite to the second air extraction channel.

7. The vacuum bag molding apparatus of claim 4, wherein The vacuum bag forming device further comprises a feeding channel, the feeding channel comprises: a third pipeline arranged in the first space and extending along the first direction; a fourth pipeline connected with the third pipeline and extending along the second direction, the fourth pipeline is used for connecting the third pipeline with a storage device.

8. The vacuum bag molding apparatus of claim 7, wherein, The first pipeline and the second pipeline are connected through a tee connector; and / or, The third pipeline and the fourth pipeline are connected through a tee connector.

9. The vacuum bag molding apparatus of claim 7, wherein, Along the first direction, part of the protruding structure is opposite to the third pipeline.

10. The vacuum bag molding apparatus of claim 1, wherein, The vacuum bag forming device further comprises: a release cloth located in the sealed space, the release cloth covers the preform on the mold; a flow guide net located in the sealed space and located on the side of the release cloth away from the preform; Along the second direction, the size of the flow guide net is 45% to 55% of the size of the release cloth.

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