Patent Application
20190115167
The present invention relates to three-dimensional circuit structures and, more particularly, to a three-dimensional circuit membrane, a key having the three-dimensional circuit membrane, and a method of manufacturing the three-dimensional circuit membrane.
Technology, especially computer technology, is ever-evolving and so are peripheral products, such as keyboards, mice, and trackballs. As for the peripheral products, every user not only cherishes their ease of use, but also wants to enjoy seeing and touching them while using them.
Recently techniques of using electronic paper as a display unit of a single key on a keyboard were put forth. For example, U.S. Pat. No. 9,360,948 and Taiwan patent 1556137 put forth a keyboard system with changeable key displays. However, the conventional way to control a signal circuit for electronic paper still requires connecting a circuit board and a display panel by a connector or a flexible flat cable so that signals sent from an external control component are transmitted to the display panel to form a circuit control path, thereby leading to an intricate manufacturing process and high costs as a result of its structure and design. Furthermore, in practice, the keys interfere with each other and thus affect each other to the detriment of use, maintenance, and repair.
Conventional keyboards are adapted for use with various display units, such as e-ink displays, organic electroluminescent displays, and thin-film transistor liquid crystal displays, so that a single key can change symbols displayed and adapted for different languages or usage scenarios. To this end, the structure of a single key has to be modified to contain and control a display unit. The modification, however, is likely to increase the thickness and structural complexity of the key.
In an embodiment, a three-dimensional circuit membrane comprises a thermoplastic plastic sheet and a wiring. The thermoplastic plastic sheet has a surface and a thermoformed structure outwardly protruding from the surface. The wiring is printed on the surface and extends to the thermoformed structure.
In some embodiments, thermoformed structure has a hollowed portion beside the wiring such that the thermoformed structure collapses easily.
In some embodiments, the wiring comprises a connecting segment and an ascending segment which the connecting segment adjoins, the connecting segment being disposed on a top of the thermoformed structure, and the ascending segment being disposed on a sidewall of the thermoformed structure.
In an embodiment, a key having a three-dimensional circuit membrane comprises a display unit, a connecting base, and the three-dimensional circuit membrane. The display unit has a display surface and an engaging surface. Electrodes are disposed on the engaging surface. The connecting base has a receiving surface, a snap-engaging surface, and a conduction pathway which penetrates the receiving surface and the snap-engaging surface. The receiving surface underpins the display unit. The conduction pathway is electrically connected to the electrodes. The thermoformed structure of the three-dimensional circuit membrane is disposed below the snap-engaging surface. The wiring of the three-dimensional circuit membrane is electrically connected to the conduction pathway.
In some embodiments, the key having a three-dimensional circuit membrane further comprises a rubber dome. The rubber dome is received in thermoformed structure.
In some embodiments, the key having a three-dimensional circuit membrane further comprises a support mechanism. The snap-engaging surface integrally forms a snap-engaging structure. One end of the support mechanism is engaged with the snap-engaging structure.
In an embodiment, a method of manufacturing a three-dimensional circuit membrane comprises the steps of: coating a conductive ink on a surface of a thermoplastic plastic sheet by screen printing to form a wiring; and forming an outwardly-protruding thermoformed structure at an end of the wiring by vacuum thermoforming, wherein the thermoformed structure is collapsible. The thermoformed structure is collapsible.
In some embodiments, the method of manufacturing the three-dimensional circuit membrane further comprises, before the step of coating the conductive ink, increasing surface roughness of the surface of the thermoplastic plastic sheet to increase adhesion of the conductive ink.
In some embodiments, the method of manufacturing the three-dimensional circuit membrane further comprises hollowing out the thermoformed structure beside the wiring so that the thermoformed structure collapses easily.
In an embodiment, a method of manufacturing a key, comprising the steps of: coating a conductive ink on a surface of a thermoplastic plastic sheet by screen printing to form a wiring; forming a thermoformed structure at an end of the wiring by vacuum thermoforming, wherein the thermoformed structure protrudes outward; hollowing out the thermoformed structure beside the wiring by laser cutting; disposing a connecting base on the thermoformed structure; and disposing a rubber dome below the thermoformed structure.
In conclusion, the three-dimensional circuit membrane provided by the present invention is applicable to a key switch (dome switch) with the rubber dome or a key switch (scissor-switch) with the support mechanism which is scissor-shaped or butterfly-shaped. The three-dimensional circuit membrane not only contains the rubber dome and/or circumvents the support mechanism but also provides a signal circuit disposed on or outside the rubber dome and adapted to control the display unit, so as to send the control signals to the display unit. The three-dimensional circuit membrane collapses easily when pressed but rebounds when not. When applied to the key with the display unit, the three-dimensional circuit membrane provided by the present invention can be easily put together to form the key thus required, and the finished key meets users' expectations for seeing and touching the key pleasantly. When applied to a keyboard with multiple keys, the three-dimensional circuit membrane provided by the present invention provides a control circuit of the display unit and prevents interference from taking place between the keys, thereby enhancing ease of use. A method of manufacturing the three-dimensional circuit membrane and/or a method of manufacturing the keys, provided by the present invention, are effective in processing all the keys of a keyboard simultaneously in a single process, for example, forming the thermoformed structures and the wirings of all the keys of a keyboard simultaneously, so as to simplify processes, reduce manufacturing costs, and enable mass production.
The features and advantages of the present invention are detailed hereinafter with reference to the preferred embodiments. The detailed description is intended to enable persons skilled in the art to gain insight into the technical contents disclosed herein and implement the present invention accordingly. In particular, persons skilled in the art can easily understand the objectives and advantages of the present invention by referring to the disclosure of the specification, the claims, and the accompanying drawings.
In some embodiments, the wiring 5 on the thermoformed structure 43 comprises a connecting segment 511 and an ascending segment 512. The connecting segment 511 adjoins the ascending segment 512. The connecting segment 511 is disposed on the top of the thermoformed structure 43, whereas the ascending segment 512 is disposed on a sidewall of the thermoformed structure 43. The hollowed portion 8 is disposed on the sidewall of the thermoformed structure 43. After a user has pressed on the top of the thermoformed structure 43, the thermoformed structure 43 restores its original shape because of the support provided by the sidewall.
Referring to
In some embodiments, the three-dimensional circuit membrane 100 is disposed in a key to provide a delivery path for control signals, such as a display signal for a key pattern or an enable signal for a key light source. If the key with the three-dimensional circuit membrane 100 is for use with a keyboard which has multiple keys, the thermoformed structures 43 formed on the three-dimensional circuit membrane 100 correspond in quantity and position to the keys of the keyboard. Therefore, a single said three-dimensional circuit membrane 100 can be in use with one or more keys or even the keyboard in its entirety, by changing the quantity and positions of the thermoformed structures 43 formed on the thermoplastic plastic sheet 4 as needed. For illustrative sake, the description below is exemplified by one key.
In this embodiment, the connecting base 1 is manufactured by plastic injection molding, and the receiving surface 11 of the connecting base 1 is substantially parallel to the snap-engaging surface 12 so as to reduce the total thickness of the key 200.
In an embodiment, a limiting structure 13 is disposed at the periphery of the receiving surface 11. The limiting structure 13 limits positions of an electronic paper 3 and the connecting base 1 relative to each other.
In some embodiments, the display unit 3 is a thin-paper or thin-board electronic paper. A plurality of display zones is defined on the display surface 31 of the display unit 3. A transparent keycap on the display surface 31 or the display surface 31 is blackened with a black pigment, and then the black pigment coated on the display surface 31 or the transparent keycap is hollowed out by a laser nameplate. The display surface 31 brightens, darkens, or alternates black and white, so as to change contrast, brightness or shades of pictures and symbols, such as alphabets, on the display unit 3 or the transparent keycap, thereby varying how conspicuous the hollow-out symbols are. In an embodiment, a plurality of display zones is defined on the display surface 31 of the display unit 3, and it is feasible to control whether symbols in the display zones display independently of each other, thereby displaying one symbol only or multiple symbols simultaneously.
Take three display zones as an example, the three display zones are coupled to three first electrodes, respectively, but to one second electrode jointly. Voltage changes resulting from electrically connecting the three display zones to the first electrodes and to the second electrode intermittently enable the corresponding ones of the display zones to brighten, darken, or alternate black and white, thereby determining whether to display the symbols of the display zones. Therefore, the four electrodes 33 (three first electrodes and one second electrode) are disposed on the engaging surface 32 of the display unit 3. The connecting base 1 has four upper contacts 11a, four conduction pathways 2, and four lower contacts 11b. A first end of each conduction pathway 2 is disposed on the receiving surface 11 and coupled to a corresponding one of the upper contacts 11a. The four upper contacts 11a correspond in position to the four electrodes 33, respectively. A second end of each conduction pathway 2 is disposed on the snap-engaging surface 12 and coupled to a corresponding one of the lower contacts 11b. Therefore, when the display unit 3 is superimposed on the connecting base 1, the electrodes 33 of the display unit 3 are electrically connected to the lower contacts 11b by the upper contacts 11a and the conduction pathways 2, respectively.
The pressing wirings 51 on the thermoformed structure 43 are defined as four discrete branch wirings 51a˜51d. The connecting segments 511 of the four branch wirings 51a˜51d correspond in position to the four lower contacts 11b on the snap-engaging surface 12, respectively. Therefore, when the three-dimensional circuit membrane 100 is superimposed on the connecting base 1, the lower contacts 11b on the snap-engaging surface 12 are adhered to the connecting segments 511 of the branch wirings 51a˜51d, respectively, so that the branch wirings 51a˜51d are electrically connected to the four electrodes 33 by the lower contacts 11b, the conduction pathways 2, and the upper contacts 11a.
The four branch wirings 51a˜51d are electrically connected to the contacts 53 through the connecting wirings 52 which the four branch wirings 51a˜51d are coupled to; hence, the four branch wirings 51a˜51d are electrically connected to control components outside the three-dimensional circuit membrane 100. Therefore, signals generated from the control components which the three-dimensional circuit membrane 100 is connected to can be delivered to the display unit 3 by the wiring 5, so as to control the time when the display zones on the display surface 31 brighten, darken, or alternate black and white.
Although the aforesaid embodiment is exemplified by the four electrodes 33 corresponding in position to the four branch wirings 51a˜51d, the quantity of the electrodes 33 and the quantity of the corresponding branch wirings vary with the quantity of the display zones. Therefore, the quantity of the branch wirings is subject to changes as needed. Accordingly, the present invention includes, but is not limited to, the four branch wirings 51a˜51d.
In some embodiments, as shown in
In an embodiment, the snap-engaging surface 12 further comprises four snap-engaging structures 14. The snap-engaging structures 14 snap-engage with a scissor-shaped or butterfly-shaped support mechanism 10 to form a restorable key switch (scissor-switch). The support mechanism 10 has a central depletion region 10a. The thermoformed structure 43 is superimposed on the rubber dome 6 and penetratingly disposed within the central depletion region 10a. The upper end of the support mechanism 10 snap-engages with the snap-engaging structures 14. A fixing base 10′ is disposed below the signal delivery component 7. The fixing base 10′ is usually a sheet metal element. In this embodiment, the fixing base 10′ comprises at least one positioning stand 10b which penetrates the signal delivery component 7 and the three-dimensional circuit membrane 100 to snap-engage with the lower end of the support mechanism 10. Hence, when the key 200 is pressed, the support mechanism 10 enables the key 200 to return to a pre-press height easily. The snap-engaging structures 14 are integrally formed on the snap-engaging surface 12 by plastic injection molding.
The method further involves forming the thermoformed structure 43 at an end of the wiring 5 by vacuum thermoforming, wherein the thermoformed structure 43 protrudes outward from the upper surface 41 (step S2). The thermoformed structure 43 has therein a hollow core; hence, when pressed under an external force, the thermoformed structure 43 collapses. In an embodiment of step S2, four discrete branch wirings 51′ are disposed on the top of the thermoformed structure 43.
In some embodiments, before step S1, it is feasible to increase surface roughness of the upper surface 41 of the thermoplastic plastic sheet 4 so as to increase adhesion of the conductive ink. The way of increasing the surface roughness entails, for example, rubbing the upper surface 41 of the thermoplastic plastic sheet 4 with sandpaper. Alternatively, the way of increasing the surface roughness entails making non-uniform tiny dents on the thermoplastic plastic sheet 4 by a laser technique to increase the surface roughness of the upper surface 41 of the thermoplastic plastic sheet 4. However, the present invention is not restrictive of the way to increase the surface roughness of the upper surface of the thermoplastic plastic sheet 4.
In some embodiments of step S3, the step of hollowing out the thermoformed structure 43 is effectuated by laser cutting, but the present invention is not limited thereto. In a variant embodiment, the thermoformed structure 43 is hollowed out by any other cutting techniques, such as knife-cutting and line-cutting.
The present invention is not restrictive of the order in which step S2 and step S3 occur. In some embodiments, step S2 either precedes or follows step S3; hence, for example, upon completion of step S1, the step S3 of hollowing out the thermoformed structure 43 beside the wiring 5 is performed and then followed by the step S2 of forming the thermoformed structure 43 at an end of the wiring 5 by vacuum thermoforming, wherein the thermoformed structure 43 protrudes outward from the upper surface 41. Likewise, the three-dimensional circuit membrane 100 is manufactured.
In some embodiments, the three-dimensional circuit membrane 100 is applicable to keyboards capable of light emission and display.
In an embodiment, after step S3 but before step S42, it is feasible to perform two other steps as follows: snap-engaging the upper end of the scissor-shaped or butterfly-shaped support mechanism 10 with the upper end of the snap-engaging structures 14; and penetratingly dispose the thermoformed structure 43 within the central depletion region 10a of the support mechanism 10.
In an embodiment of step S43, the lower end of the support mechanism 10 is fixed to the positioning stand 10b of the fixing base 10′, whereas the positioning stand 10b penetrates the signal delivery component 7 and the three-dimensional circuit membrane 100 to snap-engage with the lower end of the support mechanism 10 and confine the rubber dome 6 between the thermoformed structure 43 and the signal delivery component 7.
In conclusion, the three-dimensional circuit membrane 100 provided by the present invention is applicable to a key switch (dome switch) with the rubber dome 6 or a key switch (scissor-switch) with the support mechanism 10 which is scissor-shaped or butterfly-shaped. The three-dimensional circuit membrane 100 not only contains the rubber dome and/or circumvents the support mechanism but also provides a signal circuit disposed on or outside the rubber dome 6 and adapted to control the display unit 3, so as to send the control signals to the display unit 3. The three-dimensional circuit membrane 100 collapses easily when pressed but rebounds when not. When applied to the key 200 with the display unit 3, the three-dimensional circuit membrane 100 provided by the present invention can be easily put together to form the key 200 thus required, and the finished key 200 meets users' expectations for seeing and touching the key 200 pleasantly. When applied to a keyboard with multiple keys 200, the three-dimensional circuit membrane 100 provided by the present invention provides a control circuit of the display unit 3 and prevents interference from taking place between the keys 200, thereby enhancing ease of use. A method of manufacturing the three-dimensional circuit membrane and/or a method of manufacturing the keys 200, provided by the present invention, are effective in processing all the keys of a keyboard simultaneously in a single process, for example, forming the thermoformed structures 43 and the wirings of all the keys 200 of a keyboard simultaneously, so as to simplify processes, reduce manufacturing costs, and enable mass production.
Although the present invention is disclosed above by preferred embodiments, the preferred embodiments are not restrictive of the present invention. Slight changes and modifications made by persons skilled in the art to the preferred embodiments without departing from the spirit of the present invention must be deemed falling within the scope of the present invention. Accordingly, the legal protection for the present invention should be defined by the appended claims.
