Manufacturing Process of Flexible Substrate Overmolding Structure and Flexible Substrate Overmolding Structure

Abstract

To provide an overmolding structure of a flexible substrate and a production process thereof.SOLUTION: This invention discloses a production process of a flexible substrate overmolding structure, wherein the production process includes: an FPC overmolding step for processing the FPC substrate main body and the FPC for static structure rubber strip to tightly bond with each other to form an integral structure; a support medium assembly step for assembling two connector assemblies to both ends of an elastic support medium; a main body assembly step for assembling an assembly body obtained in the FPC overmolding step and the assembly body obtained in the support medium assembly step; and a soft rubber overmolding step for forming a soft rubber cover by overmolding on an outside of a whole structure where the FPC substrate main body, the FPC for static structure rubber strip, the elastic support medium, and the two connector assembly have been assembled together. This invention can satisfy application requirements such as large deformation width and high deformation frequency.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a manufacturing process of a member having a flexible substrate, and particularly to a manufacturing process of a flexible substrate overmolding structure and a flexible substrate overmolding structure.

Background Art

[0002] In the prior art, a flexible substrate (FPC substrate) is a printed circuit board with high reliability and excellent flexibility, and has the characteristics of high wiring density, light weight, thin thickness, and excellent bendability. In particular, it can be bent, wound, and folded freely, can be arbitrarily arranged according to the requirements of the space layout, and can realize arbitrary movement and expansion / contraction in three-dimensional space. With the explosive growth of wearable devices, flexible displays, and smart (wearable) devices, the demand for flexible substrates has increased significantly and it is being used more and more widely in the industry. However, the bendability of FPC is restricted by the traditional direct overmolding process flow. In particular, when repeated bending is required or in the case of connection with an overmolded flexible body with a large width of stretching and contracting movement, the flexibility and fatigue resistance of the copper foil of the printed circuit are significantly reduced. Therefore, FPC substrates are very rarely used for internal connections of overmolded flexible bodies with a large deformation width, and generally are only used for structures wrapped with hard rubber without deformation or flexible bodies wrapped with soft rubber with a small deformation width or a low deformation frequency.

Summary of the Invention

Problems to be Solved by the Invention

[0003] In view of the deficiencies of the prior art, the technical problem to be solved by the present invention is to provide a flexible substrate overmolding structure and its manufacturing process that can meet application requirements such as a large deformation width and a high deformation frequency.

Means for Solving the Problems

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions.

[0005] A manufacturing process of a flexible substrate overmolding structure, wherein the flexible substrate overmolding structure includes an FPC substrate body, an FPC shaping rubber strip, an elastic support, two connector assemblies, and one soft rubber cover. The manufacturing process includes an FPC overmolding step of processing the FPC substrate body and the FPC shaping rubber strip into an integral structure so as to be in close contact, a support assembly step of assembling two connector assemblies at both ends of the elastic support, a main body assembly step of assembling the assembly obtained in the FPC overmolding step and the assembly obtained in the support assembly step, and a soft rubber overmolding step of forming a soft rubber cover by overmolding on the outside of the entire structure assembled with the FPC substrate body, the FPC shaping rubber strip, the elastic support, and the two connector assemblies.

[0006] Preferably, in the manufacturing step, the mold forming process of processing the FPC substrate body and the FPC shaping rubber strip into an integral structure includes vacuum casting, mold injection molding, or mold hot pressing.

[0007] Preferably, the connector assembly includes a functional case and an internal connector provided so as to be embedded in the functional case and formed together with the functional case by an overmolding process.

[0008] A flexible substrate overmolding structure, wherein the flexible substrate overmolding structure includes an FPC substrate body, an FPC shaping rubber strip, an elastic support, two connector assemblies, and one soft rubber cover. The two connector assemblies are respectively arranged inside the left and right ends of the soft rubber cover. The FPC substrate body, the FPC shaping rubber strip, and the elastic support are all arranged inside the soft rubber cover. Both ends of the FPC substrate body penetrate through the two connector assemblies and extend outward. The left and right ends of the elastic support and the left and right ends of the FPC shaping rubber strip are fixedly connected corresponding to the two connector assemblies. The FPC substrate body is in close contact with the FPC shaping rubber strip to form an integral structure, and in the region where the FPC substrate body is in close contact with the FPC shaping rubber strip, a deformed portion that is bent multiple times is formed.

[0009] Preferably, the deformed portion is bent in a wave shape such as an S-shaped waveform, a triangular waveform, a square waveform, a V-shaped waveform, or a trapezoidal waveform.

[0010] Preferably, the deformed portion is bent in a spiral shape such as a cylindrical spiral, a conical spiral, or a spindle-shaped spiral.

[0011] Preferably, on the side of the FPC shaping rubber strip facing the FPC substrate body, an adhering portion is provided whose surface shape is the same as the curved shape of the deformed portion and which is adhered to the deformed portion.

[0012] Preferably, the connector assembly includes a functional case and an internal connector provided to be embedded in the functional case.

[0013] Preferably, two insertion blocks respectively inserted into the two internal connectors are respectively formed at the left and right ends of the FPC shaping rubber strip.

[0014] Preferably, a slit through which the FPC substrate body passes is formed at the joint between the insertion block and the rubber strip for FPC shaping.

Advantages of the Invention

[0015] In the flexible substrate overmolding structure and its manufacturing process described in the present invention, while embedding the connector assemblies at both the left and right ends of the soft rubber cover respectively, and providing the FPC substrate body, the rubber strip for FPC shaping, and the elastic support inside the soft rubber cover, the present invention uses a mold forming process to process the FPC substrate body and the rubber strip for FPC shaping into an integrated structure, ensuring that the FPC substrate body and the rubber strip for FPC shaping are in close contact. At the same time, in the region where the FPC substrate body is in close contact with the rubber strip for FPC shaping, a deformed portion that has been bent multiple times is formed. The entire soft rubber cover and its internal members can not only meet the requirement of having a large deformation width due to the action of the deformed portion that has been bent multiple times when operations such as twisting, bending, curling, stretching, and compression are applied, but also have the ability to withstand high-frequency deformation. Therefore, it can be applied to various types of products such as wearable devices, flexible display devices, and smart terminal devices.

Brief Description of the Drawings

[0016]

Figure 1

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Embodiments for Carrying Out the Invention

[0017] Hereinafter, the present invention will be described in more detail with reference to the drawings and embodiments.

[0018] The present invention discloses a manufacturing process of a flexible substrate overmolding structure. As shown in FIGS. 1 to 8, the flexible substrate overmolding structure includes an FPC substrate body 1, a rubber strip 2 for FPC shaping, an elastic support 3, two connector assemblies 4, and one soft rubber cover 5. The manufacturing process includes an FPC overmolding step of processing the FPC substrate body 1 and the rubber strip 2 for FPC shaping into an integral structure so as to be in close contact with each other, a support assembly step of assembling two connector assemblies 4 at both ends of the elastic support 3, a main body assembly step of assembling the assembly obtained in the FPC overmolding step and the assembly obtained in the support assembly step, a soft rubber overmolding step of forming a soft rubber cover 5 by overmolding on the outside of the entire structure assembled with the FPC substrate body 1, the rubber strip 2 for FPC shaping, the elastic support 3, and the two connector assemblies 4.

[0019] In the above process flow, while embedding the connector assemblies 4 at both the left and right ends of the soft rubber cover 5 respectively, and providing the FPC substrate body 1, the rubber strip 2 for FPC shaping, and the elastic support 3 inside the soft rubber cover 5, the present invention uses a mold forming process to process the FPC substrate body 1 and the rubber strip 2 for FPC shaping into an integral structure, ensuring that the FPC substrate body 1 and the rubber strip 2 for FPC shaping are in close contact. At the same time, in the region where the FPC substrate body 1 is in close contact with the rubber strip 2 for FPC shaping, a deformed portion 10 that has been bent multiple times is formed. The entire soft rubber cover 5 and its internal members can not only meet the requirement of having a large deformation width due to the action of the deformed portion 10 that has been bent multiple times when operations such as twisting, bending, curling, stretching, and compression are applied, but also have the ability to withstand high-frequency deformation. Therefore, it can be applied to various types of products such as wearable devices, flexible display devices, and smart terminal devices.

[0020] In one preferred form, in the manufacturing step, the mold forming process for processing the FPC substrate body 1 and the rubber strip 2 for FPC shaping into an integral structure includes vacuum casting, mold injection molding, or mold hot pressing. Compared with the means in conventional technologies such as manual bending forming and cold extrusion forming by a mold, this embodiment can ensure the stability of the rubber strip 2 for FPC shaping after being shaped and maintain an even distribution of the stress received when the FPC substrate body 1 is deformed.

[0021] Furthermore, the connector assembly 4 includes a functional case 40 and an internal connector 41 that is provided to be embedded in the functional case 40 and is molded together with the functional case by an overmolding process. Specifically, in this step, the assembly process of the functional case 40 and the internal connector 41 includes processes such as adhesive connection, mold overmolding, ultrasonic welding, and screw fixing.

[0022] This embodiment further relates to a flexible substrate overmolding structure. As shown in FIGS. 1 to 7, the flexible substrate overmolding structure includes an FPC substrate body 1, an FPC shaping rubber strip 2, an elastic support 3, two connector assemblies 4, and one soft rubber cover 5. The two connector assemblies 4 are respectively arranged inside the left and right ends of the soft rubber cover 5. The FPC substrate body 1, the FPC shaping rubber strip 2, and the elastic support 3 are all arranged inside the soft rubber cover 5. Both ends of the FPC substrate body 1 extend outward through the two connector assemblies 4. The left and right ends of the elastic support 3 and the left and right ends of the FPC shaping rubber strip 2 are fixedly connected corresponding to the two connector assemblies 4. The FPC substrate body 1 is in close contact with the FPC shaping rubber strip 2 to form an integral structure. In the region where the FPC substrate body 1 is in close contact with the FPC shaping rubber strip 2, a deformed portion 10 that is bent multiple times is formed.

[0023] The deformed portion 10 of the FPC substrate body 1 may have multiple types of bending forms. For example, the deformed portion 10 is bent in a wave shape such as an S-shaped wave, a triangular wave, a square wave, a V-shaped wave, or a trapezoidal wave. Alternatively, the deformed portion 10 is bent in a spiral shape such as a cylindrical spiral, a conical spiral, or a spindle-shaped spiral. However, this is only a preferred application example of the present invention and is not for limiting the protection scope of the present invention. According to the design requirements, it may be designed as other structures that deform periodically or curve irregularly.

[0024] In actual application, after the processing by the mold forming process is completed on the FPC shaping rubber strip 2, an adhering portion 20 is formed. Specifically, on the side of the FPC shaping rubber strip 2 facing the FPC substrate body 1, an adhering portion 20 is provided whose surface shape is the same as the bending shape of the deformed portion 10 and which is adhered to the deformed portion 10.

[0025] In this embodiment, the connector assembly 4 includes a functional case 40 and an internal connector 41 provided so as to be embedded in the functional case 40.

[0026] Please refer to FIG. 5. When the elastic support 3 is fixedly attached between two connector assemblies 4, both ends of the elastic support 3 are respectively inserted into two internal connectors 41. In actual applications, the cross-section of the elastic support 3 is preferably circular, rectangular, triangular or polygonal, and its material can be various metals (such as iron strips, steel strips, spring steel, nickel-titanium alloys, etc.) or various construction plastic materials (such as polycarbonate (PC), acrylonitrile-butadiene-styrene (ABS), polypropylene (PP), polyamide (PA), etc.). In actual applications, the extended shape of the elastic support 3 is not limited to the arc shape shown in the drawing and can be adjusted and set as appropriate according to needs.

[0027] In order to better fix the FPC shaping rubber strip 2, in this embodiment, two insertion blocks 21 respectively inserted into two internal connectors 41 are formed at the left and right ends of the FPC shaping rubber strip 2.

[0028] As a preferred form, a slit 22 through which the FPC substrate body 1 passes is formed at the joint between the insertion block 21 and the FPC shaping rubber strip 2 to reinforce the engagement relationship between the FPC substrate body 1 and the FPC shaping rubber strip 2.

[0029] In this embodiment, the overmolding materials of the soft rubber cover 5 and the FPC shaping rubber strip 2 are separately of a two-part structure, and by adjusting the different materials, hardnesses or colors of the two, various combinations of different hardnesses or colors can be obtained.

[0030] In a preferred embodiment of the present invention, the hardness of the soft rubber cover 5 is preferably equal to or greater than the hardness of the rubber strip 2 for FPC shaping. Specifically, while the rubber strip 2 for FPC shaping is required to have a low hardness and a soft texture, the hardness of the soft rubber cover 5 may be slightly reduced or slightly increased. Thereby, the expandability of the product can be improved, various expression forms of the product can be enriched, and as a result, the application needs in different scenarios can be satisfied.

[0031] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. All changes, equivalent substitutions, or improvements made within the technical scope of the present invention shall be included in the protection scope of the present invention.

Claims

1. A manufacturing process of a flexible substrate overmolding structure, the flexible substrate overmolding structure includes an FPC substrate body (1), an FPC shaping rubber strip (2), an elastic support (3), two connector assemblies (4), and a soft rubber cover (5), the manufacturing process includes: an FPC overmolding step of processing the FPC board body (1) and the FPC shaping rubber strip (2) into an integral structure so as to be in close contact with each other; a support assembly step of assembling two connector assemblies (4) on both ends of an elastic support (3); a main body assembling step of assembling the assembly obtained in the FPC overmolding step and the assembly obtained in the support assembling step; and a soft rubber overmolding step of overmolding a soft rubber cover (5) on the outside of the entire structure in which the FPC board body (1), the FPC shaping rubber strip (2), the elastic support (3), and the two connector assemblies (4) are assembled.

2. The manufacturing process of the flexible substrate overmolding structure described in claim 1, characterized in that in the FPC overmolding step, a mold molding process for processing the FPC substrate body (1) and the FPC shaping rubber strip (2) into an integral structure includes vacuum casting, mold injection molding, or mold hot pressing.

3. 2. The manufacturing process of a flexible substrate overmolding structure according to claim 1, characterized in that the connector assembly (4) includes a functional case (40) and an internal connector (41) that is embedded in the functional case (40) and is molded together with the functional case (40) by an overmolding process.

4. A flexible circuit board overmolding structure includes an FPC board body (1), an FPC-shaped rubber strip (2), an elastic support (3), two connector assemblies (4), and a soft rubber cover (5), the two connector assemblies (4) are respectively disposed inside the left and right ends of the soft rubber cover (5), the FPC board body (1), the FPC-shaped rubber strip (2), and the elastic support (3) are all disposed inside the soft rubber cover (5), and both ends of the FPC board body (1) are respectively disposed inside the soft rubber cover (5), and the two connector assemblies (4 ... a flexible substrate overmolding structure, the flexible substrate overmolding structure being characterized in that the flexible substrate overmolding structure extends outward through a connector assembly (4), the left and right ends of the elastic support (3) and the left and right ends of the FPC-shaping rubber strip (2) are fixedly connected to correspond to the two connector assemblies (4), the FPC substrate main body (1) is in intimate contact with the FPC-shaping rubber strip (2) to form an integral structure, and a deformation portion (10) that is bent multiple times is formed in the area of ​​the FPC substrate main body (1) that is in intimate contact with the FPC-shaping rubber strip (2).

5. 5. The flexible substrate overmolding structure of claim 4, wherein the deformed portion (10) is wave-folded with an S-shaped wave, a triangular wave, a square wave, a V-shaped wave, or a trapezoidal wave, or the deformed portion (10) is spirally folded with a cylindrical spiral, a conical spiral, or a spindle spiral.

6. 5. The flexible circuit board overmolding structure according to claim 4, wherein the hardness of the soft rubber cover (5) is equal to or greater than the hardness of the FPC shaping rubber strip (2).

7. The flexible substrate overmolding structure according to claim 4, characterized in that the side of the FPC shaping rubber strip (2) facing the FPC substrate body (1) has an attachment portion (20) whose surface shape is the same as the curved shape of the deformation portion (10) and which is attached to the deformation portion (10).

8. 5. The flexible substrate overmolding structure of claim 4, wherein the connector assembly (4) includes a functional case (40) and an internal connector (41) embedded in the functional case (40).

9. The flexible substrate overmolding structure according to claim 8, characterized in that two plug-in blocks (21) are formed on both left and right ends of the FPC-shaping rubber strip (2), which are respectively inserted into two internal connectors (41).

10. The flexible substrate overmolding structure according to claim 9, characterized in that a slit (22) through which the FPC substrate body (1) passes is formed at the joint between the insertion block (21) and the FPC shaping rubber strip (2).

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