A preparation process for discontinuous conductive foam

Abstract

The present invention discloses a process for preparing discontinuous conductive foam, which mainly includes laminating a layer of adhesive tape on the bottom surface of a first conductive cloth and a layer of adhesive tape on the top surface of a second conductive cloth; laminating a foam body to the top surface of the second conductive cloth; punching the foam body into multiple equidistant foam bodies, forming spacing grooves between adjacent foam bodies after removing waste; laminating the first conductive cloth to the curved surface of the foam body; punching downwardly to form a patch at the position of the first conductive cloth corresponding to the spacing groove, and laminating the patch downwardly on the top of the second conductive cloth. The patch punched out from the first conductive sheet is laminating on the top of the second conductive sheet, which not only covers the residual adhesive exposed on the second conductive sheet, but also increases the thickness of the second conductive sheet at the spacing groove. When a worker manually peels off the conductive foam, it can effectively prevent the conductive foam from twisting at the spacing groove, facilitating the lamination of the conductive foam to the application curved surface.

Description

Technical Field

[0001] The invention belongs to the technical field of electromagnetic shielding, relates to a conductive foam, and in particular to a preparation process of a discontinuous conductive foam. Background Art

[0002] Figure 1 The figure shows a discontinuous conductive foam suitable for laminating on curved surfaces, including a foam body 10, a first conductive cloth 20 and a second conductive cloth 30. The foam has a discontinuous structure, and the first conductive cloth and the second conductive cloth are wrapped around the outside of the foam.

[0003] The traditional preparation process of the above conductive foam is:

[0004] The first step is to pre-attach the first conductive fabric to the arc-shaped upper surface of the foam body (see Figure 2 );

[0005] The second step is to punch out the first conductive cloth and the foam to form a discontinuous structure in the foam body (see Figure 3 );

[0006] Step 3: Lay the foam body onto the adhesive surface of the second conductive fabric (see Figure 4 );

[0007] Step 4: Lay the first conductive cloth and the second conductive cloth on the outside of the foam body.

[0008] In actual production, since the top of the foam body is an arc-shaped surface, the contact area between the first conductive cloth and the foam body during pre-bonding is relatively small. In the second step, during the waste discharge after punching the first conductive cloth and foam, the foam is easily caused to fall off, affecting the continuity of production.

[0009] Moreover, there is residual adhesive surface at the gap between the second conductive cloth and the foam, and the residual adhesive surface will affect the adhesion of the conductive foam to the client. Summary of the Invention

[0010] The technical problem to be solved by the present invention is to provide a conductive foam with small bending stress or even no stress.

[0011] In order to solve the above technical problems, the technical solutions adopted by the present invention are as follows:

[0012] A process for preparing discontinuous conductive foam includes foam, a first conductive cloth, and a second conductive cloth; the foam has a multi-segment structure, consisting of multiple independent foam bodies arranged in a line, with a spacing groove between adjacent sections of foam bodies; a first conductive tape is attached to the lower surface of the first conductive cloth, and a second conductive tape is attached to the upper surface of the second conductive cloth; the first conductive cloth and the second conductive cloth cover the foam, and the ends of the first conductive cloth and the end of the second conductive cloth overlap on the side of the foam to form a side edge; the first conductive cloth is provided with a slot corresponding to the spacing groove, and both ends of the slot extend to the side edge, and the top of the side edge is provided with a cut groove corresponding to the spacing groove.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] 1. This process first attaches the foam body to the top of the second conductive cloth. The contact area between the foam body and the second conductive cloth is large, and the foam body and the second conductive cloth will not separate during the waste discharge process;

[0015] 2. The patch punched out from the first conductive sheet is attached to the top of the second conductive sheet, which not only covers the residual glue exposed by the second conductive sheet, but also increases the thickness of the second conductive sheet at the corresponding spacing groove. When workers manually peel off the conductive foam, it can effectively prevent the conductive foam from twisting at the spacing groove, making it easier for the conductive foam to fit on the application surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments.

[0017] Figure 1 It is a cross-sectional view of a conductive foam in the prior art;

[0018] Figure 2 This is a schematic diagram of the first step of conductive foam processing in the prior art;

[0019] Figure 3 This is a schematic diagram of the second step of processing conductive foam in the prior art;

[0020] Figure 4 This is a schematic diagram of the third step of processing conductive foam in the prior art;

[0021] Figure 5 This is a schematic diagram of the second step of processing the conductive foam in the embodiment;

[0022] Figure 6 This is a schematic diagram of the third step of processing the conductive foam in the embodiment;

[0023] Figure 7This is a schematic diagram of the fourth step of processing the conductive foam in the embodiment;

[0024] Figure 8 This is a schematic diagram of the fifth step of processing the conductive foam in the embodiment;

[0025] Figure 9 This is a schematic diagram of the fifth preferred processing method of the conductive foam in the embodiment. DETAILED DESCRIPTION

[0026] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments.

[0027] Example

[0028] A process for preparing discontinuous conductive foam comprises the following steps:

[0029] In the first step, a layer of adhesive tape is laminated on the bottom surface of the first conductive cloth 20, a layer of adhesive tape is laminated on the top surface of the second conductive cloth 30, and a release layer is laminated on the bottom surface. This step is the raw material preparation stage. Laminating the release layer on the bottom surface of the second conductive cloth 30 first can improve the hardness of the second conductive cloth 30.

[0030] In the second step, the foam body 10 is attached to the top surface of the second conductive cloth 30 (see Figure 5 );

[0031] The third step is to punch the foam body 10 downward to form a plurality of foam bodies 11 arranged at equal distances, and then remove the waste of the foam body 10 to form spacing grooves 12 between adjacent foam bodies 11 (see Figure 6 );

[0032] Step 4: Lay the first conductive fabric 20 onto the curved surface of the foam body 10 (see Figure 7 );

[0033] Step 5: punch down the first conductive cloth 20 at the position corresponding to the spacing groove 12 to form a patch 40, and attach the patch 40 downward to the top of the second conductive cloth 30 (see Figure 8 ); wherein the size of the patch 40 may be 0.1mm-0.5mm smaller than the size of the spacing groove 12 on one side;

[0034] Step 6: Lay the first conductive fabric 20 on the side of the foam body 10;

[0035] In the seventh step, the edge of the second conductive cloth 30 is folded upward and attached to the outer side of the first conductive cloth 20 .

[0036] If the surface curvature of the conductive foam is large, a tangent line can be formed in the first conductive cloth 20 when punching the patch 40. The first conductive cloth 20 is dispersed at the tangent line to achieve maximum bending of the conductive foam.

[0037] In this process, the foam body 10 is first attached to the top of the second conductive cloth 30. The contact area between the foam body 10 and the second conductive cloth 30 is large, and the foam body 11 will not be separated from the second conductive cloth 30 during the waste discharge process.

[0038] In addition, the patch 40 punched out from the first conductive sheet is attached to the top of the second conductive sheet, which not only covers the residual glue exposed by the second conductive sheet, but also increases the thickness of the second conductive sheet corresponding to the spacing groove 12. When the worker manually peels off the conductive foam, it can effectively prevent the conductive foam from twisting at the spacing groove 12, making it easier for the conductive foam to fit on the application surface.

[0039] In the third step, punching the foam body 10 downwards can also cut the tape layer attached to the surface of the second conductive cloth 30, allowing the tape waste and foam waste to be discarded together. Even if the cutter leaves an impression in the second conductive sheet that affects its strength, the subsequent patch 40 can still strengthen it.

[0040] As a preferred embodiment of the present invention, a vacuum adsorption block is provided in the fourth step. The bottom of the vacuum adsorption block is provided with an arc-shaped adsorption surface. The vacuum adsorption block adsorbs the first conductive cloth 20 so that a part of the first conductive cloth 20 becomes an arc-shaped structure 21 (see Figure 9 ), thus laminating the first conductive sheet to the conductive foam can improve the lamination effect and lamination area between the two.

[0041] Furthermore, the vacuum block includes an inner and outer block. The outer block houses a punch for forming patch 40, while the inner block is mounted within the punch. The punch downwardly forms patch 40, and the inner and outer blocks drive the first conductive fabric 20 downward, attaching it to the foam body 11. The inner block then continues downwardly, attaching patch 40 to the top of the second conductive fabric 30. The vacuum block firmly holds the first conductive fabric 20 upward, eliminating the need for a die beneath the material. The punch also cuts the material downward without stretching it. This simplifies the equipment structure, optimizes the equipment's operational flow, and improves the efficiency of conductive foam production.

[0042] Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not limited to the embodiments shown herein, but is to be construed in the widest manner consistent with the principles and novel features disclosed herein.

Claims

1. A process for preparing discontinuous conductive foam, characterized in that: The following steps are involved: In the first step, a layer of adhesive tape is laminated on the bottom surface of the first conductive cloth, a layer of adhesive tape is laminated on the top surface of the second conductive cloth, and a release layer is laminated on the bottom surface; Step 2: Lay the foam body on the top surface of the second conductive cloth; The third step is to punch the foam body downward to form a plurality of foam bodies arranged at equal distances, and then remove the waste of the foam body to form spacing grooves between adjacent foam bodies; Step 4: Lay the first conductive cloth onto the curved surface of the foam body; Step 5: Punching downwards at the position of the first conductive cloth corresponding to the spacing groove to form a patch, and attaching the patch downwards to the top of the second conductive cloth; Step 6: Lay the first conductive cloth on the side of the foam body; Step 7: Fold the edge of the second conductive cloth upwards and attach it to the outside of the first conductive cloth.

2. A process for preparing discontinuous conductive foam according to claim 1, characterized in that: In the fourth step, a vacuum adsorption block is provided, wherein a curved adsorption surface is provided at the bottom of the vacuum adsorption block. The vacuum adsorption block adsorbs the first conductive cloth so that a part of the first conductive cloth becomes a curved structure.

3. The process for preparing a discontinuous conductive foam according to claim 2, wherein: The vacuum adsorption block includes an inner adsorption block and an outer adsorption block. A punch for forming the patch is installed in the outer adsorption block, and the inner adsorption block is installed in the punch. The punch forms the patch downward, and the inner and outer adsorption blocks drive the first conductive cloth downward to attach the first conductive cloth to the foam body. The inner adsorption block continues to move downward to attach the patch to the top of the second conductive cloth.

4. The process for preparing a discontinuous conductive foam according to claim 1, wherein: In the third step, when punching the foam body, the tape layer attached to the surface of the second conductive cloth is cut off, and the tape waste is discharged together with the foam waste.

5. The process for preparing discontinuous conductive foam according to claim 1, wherein: The size of the patch is 0.1mm-0.5mm smaller than the size of the spacing groove on one side.

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