Patent Application
20200207006
This application claims priority for China patent application no. 201811600944.7 filed on Dec. 26, 2018, the content of which is incorporated by reference in its entirety.
The present invention relates to a method of manufacturing a convex mold, and more particular to a method of manufacturing a thermoforming convex mold.
In recent years, smart devices such as smart phones, smart watches, and smart medical devices are equipped with large screens for users to view information. These smart devices with powerful functions trends towards personalization and fashion for appearance, shape, color and so on. These improvements can be achieved by an impressive shell design and related manufacturing technique.
At present, the curved shell shape is particularly attractive, and it gradually becomes the future trend of smart devices. The shape of thermoforming fixtures can be designed according to requirements. However, after the transparent substrate of a thin film sensor is thermoformed and bent, the transparent substrate has sprung back due to residual stress, and it causes failure of the thin film sensor fittingly attached with a three-dimensional curved cover glass, so that it is not easy to evaluate the quality of the thermoformed film sensor.
The primary objective of the present invention is to provide a method of manufacturing a thermoforming convex mold. In the method, the side walls of a convex structure are inwardly shrunk uniformly by 0.4 mm to 0.6 mm, and the height of the convex structure is increased by 200% to 250%, so as to prevent the quality of the file sensor attached with a curve cover from being affected by the springback effect after the thermoforming process.
In order to achieve the objective, the present invention provides a method of manufacturing a thermoforming convex mold, and the method includes following steps. First, the specification of a convex fixture is provided according to a curve shape of a thermoformed film sensor, and the curve shape has a plane portion and a curve portion downwardly and vertically extended from edges of the plane portion, the convex fixture comprises a base and a convex structure extended upwardly from a top of the base, the height of each of the convex structure and the curve portion are in a range of 1 mm to 5 mm, the shape of a top of the convex structure is the same as a shape of the plane portion, an area of the top of the convex structure is less than an area of the plane portion, and a curvature radius of a curve corner between the top and a side wall of the convex structure is lower than 2 mm and higher than 0 mm. Next, the specification is adjusted by inwardly shrinking the side walls of the convex structure by 0.4 mm to 0.6 mm uniformly, and increasing the height of the convex structure by 200% to 250%. A convex mold is produced according to the adjusted specification of the convex fixture.
According to an embodiment, the curve portion is fabricated to have four surfaces vertical to each other.
According to an embodiment, the top of the convex structure is fabricated to have a rectangular shape.
According to an embodiment, a diagonal line of the rectangular shape is fabricated to have a range of 5 inches to 7 inches.
According to an embodiment, the height of the convex structure is equal to that of the curve portion.
According to an embodiment, material of the convex mold comprises bakelite, stainless steel or graphite.
According to an embodiment, the film sensor comprises a transparent substrate and a sensing layer thereon.
According to an embodiment, material of the transparent substrate is polyethylene terephthalate (PET).
According to an embodiment, a Young's modulus of the transparent substrate is in a range of 1.5×109 Pa to 3×109 Pa.
According to an embodiment, the sensing layer further comprises a plurality of transparent electrode serials.
The structure, operating principle and effects of the present invention will be described in detail by way of various embodiments which are illustrated in the accompanying drawings.
The following embodiments of the present invention are herein described in detail with reference to the accompanying drawings. These drawings show specific examples of the embodiments of the present invention. It is to be acknowledged that these embodiments are exemplary implementations and are not to be construed as limiting the scope of the present invention in any way. Further modifications to the disclosed embodiments, as well as other embodiments, are also included within the scope of the appended claims. These embodiments are provided so that this disclosure is thorough and complete, and fully conveys the inventive concept to those skilled in the art. Regarding the drawings, the relative proportions and ratios of elements in the drawings may be exaggerated or diminished in size for the sake of clarity and convenience. Such arbitrary proportions are only illustrative and not limiting in any way. The same reference numbers are used in the drawings and description to refer to the same or like parts.
It is to be acknowledged that, although the terms ‘first’, ‘second’, ‘third’, and so on, may be used herein to describe various elements, these elements should not be limited by these terms. These terms are used only for the purpose of distinguishing one component from another component. Thus, a first element discussed herein could be termed a second element without altering the description of the present disclosure. As used herein, the term “or” includes any and all combinations of one or more of the associated listed items.
It will be acknowledged that when an element or layer is referred to as being “on,” “connected to” or “coupled to” another element or layer, it can be directly on, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly connected to” or “directly coupled to” another element or layer, there are no intervening elements or layers present.
In addition, unless explicitly described to the contrary, the word “comprise” and variations such as “comprises” or “comprising”, will be acknowledged to imply the inclusion of stated elements but not the exclusion of any other elements.
Please refer to
As shown in
The convex mold 24 can be made by material, which has heat resistance to 150° C. and can withstand a tension of the film sensor 14; for example, the material of the convex mold 24 comprises bakelite, stainless steel or graphite. The film sensor 14 can comprise a transparent substrate 26 and a sensing layer 28 disposed on the transparent substrate 26. In an embodiment, the sensing layer 28 can include a plurality of transparent electrode serials, and each transparent substrate 26 has a low dielectric constant and high transmittance, for example, the transmittance of the transparent substrate 26 can be in a range of 87% to 95%. In an embodiment, the Young's modulus of the transparent substrate 26 can be in a range of 1.5×109 Pa to 3×109 Pa. For example, the material of the transparent substrate 26 can be polyethylene terephthalate (PET). The adjustment of the specification of the convex fixture 16 must match the material of the transparent substrate 26, the height H1 of the convex structure 24, the area of the top of the convex structure 24, and the curvature radiuses r of the curve corners between the top and the side walls of the convex structure 24. In
In conclusion, the specification of the convex fixture of the present invention is provided according to the required shape of the film sensor, and the side walls of the convex structure of the convex fixture are then uniformly shrunk inwardly by 0.4 mm to 0.6 mm, and the height of the convex structure is increased by 200% to 250%, so as to prevent the laminated quality of the film sensor 14 and the curve cover from being affected by the springback effect of film sensor 14 after the thermoforming process.
The present invention disclosed herein has been described by means of specific embodiments. However, numerous modifications, variations and enhancements can be made thereto by those skilled in the art without departing from the spirit and scope of the disclosure set forth in the claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 201811600944.7 | Dec 2018 | CN | national |
