TWI430308B - Keystroke sensiing structure and calculator having the same - Google Patents

Description

Key sensing structure and computer having the same

The present invention relates to a computer, and more particularly to a key sensing structure and a computer having the same.

Computers are a common electronic product that can be used for simple mathematical calculations. A typical computer usually only performs arithmetic operations and a small number of logical operations, and cannot perform complex operations with computers. Early computers used mechanical structures to perform calculations, but with advances in semiconductor technology, most computers today are handheld microelectronic devices. Higher-order computers have the functions of trigonometric functions, statistics, and other functions, and some advanced computers even have the ability to draw.

The computer has a display screen and a keyboard, and the user can input data and perform operations by pressing a button. Below the keyboard is a button input structure formed by a polyester film (called Mylar film or PET film) and a circuit board. The polyester film has a conductive region formed by a conductive carbon film, and the circuit board has cross-connected pins or leads. When the user presses the button, the polyester film is recessed downward and contacts the circuit board. The pins are shorted to generate an input signal. The computer uses the pin to determine if the button pressed by the user is used for calculation.

Usually, there is a columnar structure under the button. When the button is pressed, the columnar structure exerts pressure on the polyester film to make the polyester film contact the circuit board. When the contact area between the polyester film and the circuit board is not large enough, there is a possibility that the positive and negative electrodes on the circuit board may be short-circuited and the signal input error may occur.

The invention provides a button sensing structure and a computer having the same, wherein the button sensing structure respectively provides a circuit on the substrate and the polyester film. The gold finger setting area of the polyester film is further coated with a layer of polyester printing ink to strengthen the adhesion strength between the gold finger and the polyester film. Any contact between the contact pads on the polyester film and the contact pads on the substrate produces the correct signal. Thereby, the correctness and durability of the computer receiving the button signal can be improved.

The invention provides a button sensing structure and a computer therewith. The computer comprises a body and a button sensing structure, and the body has a display unit and a button unit. The button sensing structure includes a substrate, a polyester film and a conductive tape. The substrate has a first circuit and a plurality of first gold fingers, the first circuit having a plurality of bare first contact pads. a polyester film disposed on the substrate and having a second circuit and a plurality of second gold fingers, the second circuit having a plurality of bare second contact pads corresponding to the first contact pads, wherein each of the plurality There is a gap between the two contact pads and the corresponding first contact pads. The conductive tape is adhered to one side of the substrate and one side of the polyester film for electrically connecting the first gold fingers and the second gold fingers. Wherein, the polyester film has a setting area, and the setting area is coated with a polyester ink layer to set the second gold fingers, wherein the second gold fingers are disposed on the coated polyester ink layer. on.

In an embodiment of the present invention, the conductive tape has a plurality of linear conductive regions, and the linear conductive regions are correspondingly connected to the first gold fingers and the second gold fingers, wherein the conductive tape is folded over and disposed on the substrate Between the polyester film and the polyester film. The first circuit and the second circuit are disposed face to face. The second gold finger is correspondingly connected to the second contact pad.

In an embodiment of the invention, the substrate is coated with an insulating layer, and the insulating layer has a plurality of openings corresponding to the first contact pads to expose the plurality of A contact pad. The polyester film has a plurality of embossed portions, and the second contact pads are disposed on the inner side surfaces of the embossed portions.

In an embodiment of the invention, the trace of the second circuit comprises a silver paste layer and a carbon film layer, wherein the silver glue layer is coated on the polyester film, and the carbon film layer is coated on the silver glue. Above the layer to cover the silver glue layer.

Based on the above, the button sensing structure of the present invention directly places two circuits on the polyester film and the substrate, so that it is possible to detect whether the contact pads of the polyester film and the contact pads of the substrate are in contact with each other. The button signal was detected. Thereby, the computer having the button sensing structure can more accurately sense whether the button is pressed. Polyester ink is coated on the polyester film to improve the adhesion between the gold finger and the polyester film, thereby strengthening the adhesion strength between the gold finger and the polyester film.

The above described features and advantages of the present invention will be more apparent from the following description.

Please refer to FIG. 1 and FIG. 2. FIG. 1 is a schematic diagram of a computer according to an embodiment of the present invention. FIG. 2 is a schematic diagram of a key sensing structure according to an embodiment of the present invention. The computer 100 includes a body 101, a display unit 110, and a button unit 120. The body 101 has a button sensing structure 200 as shown in FIG. The button sensing structure 200 is located below the button unit 120 for detecting a button pressed by a user. The key sensing structure 200 includes a substrate 210, a polyester film 220, and a conductive tape 230. The polyester film 220 is disposed on the substrate 210, and the conductive tape 230 is folded in half and disposed between the substrate 210 and the polyester film 220 to electrically connect the gold finger 211 on the polyester film 220 with the gold finger on the substrate 210. .

Referring to FIG. 3, FIG. 3 is a schematic structural diagram of a key sensing structure 200 according to an embodiment of the present invention. The substrate 210 has a first circuit 215 and a plurality of first gold fingers 211. The first circuit 215 has a plurality of bare electrodes. First contact pad 212. The polyester film 220 has a second circuit 225. The second circuit 225 has a plurality of second gold fingers 221 and a plurality of second contact pads 222 corresponding to the first contact pads 212. The second circuit 225 is then connected to the second gold finger 221. The first contact pad 212 is, for example, a contact pad formed of a copper foil, and the second contact pad 222 is, for example, a contact pad formed of a silver paste and a conductive carbon film. The first circuit 215 and the second circuit 225 are disposed face to face, and the first contact pad 212 corresponds to the position of the second contact pad 222, but has a gap therebetween. Since the conductive tape 230 is connected to the first gold finger 211 on the substrate 210 and the second gold finger 221 on the polyester film 220, the circuit on the substrate 210 can be connected to all of the second circuit 225 through the first gold finger 221. Second contact pad 222. The material of the first gold finger 211 is, for example, copper, and the material of the second gold finger 221 is, for example, a carbon film or a copper foil. However, the embodiment is not limited thereto.

Under normal conditions, the first contact pad 212 is separate from the second contact pad 222. When the user presses the button, the polyester film 220 is subjected to pressure to be recessed toward the substrate 210, so that the first contact pad 212 contacts the second contact pad 222. The computer 100 can detect whether the button pressed by the user, such as a numeric key or a function key of the operation, is detected by whether the first contact pad 212 and the second contact pad 222 are short-circuited. For example, the first contact pad 212 and the second contact pad 222 are short-circuited to provide a high voltage to the first contact pad 212, and then the first contact pad 212 is determined by detecting the potential change of the second contact pad 222. Whether the second contact pad 222 is short-circuited. It should be noted that the present invention is not limited to this detection method.

Further, the substrate 210 is, for example, a printed circuit board, and its surface may be coated with an insulating layer (green lacquer) (not shown) for protecting the wiring on the printed circuit board. There may be an opening on the insulating layer corresponding to the first contact pad 212 to expose the first contact pad 212. In order to enhance the adhesion between the gold finger and the polyester film 220, a polyester printing ink is first applied to the setting area 241 of the second gold finger 221 where the polyester film 220 is disposed to form a polyester ink layer. 240, then a second gold finger 221 is formed on the polyester ink layer 240. The polyester ink layer 240 can strengthen the adhesion of the second gold finger 221 to the polyester film 220, and prevent the second gold finger 221 from falling off.

The polyester ink is usually a chemical compound, and its composition is, for example, graphite (Graphite), carbon black, butyl cellosove acetate, and butyl carbitol acetate. ), Butyl carbitol, Phenol resin, 1-butanol and Formaldehyde are mixed in a certain ratio. It should be noted that the above polyester inks may have different compositions and proportions according to each brand. This embodiment does not limit the composition and proportion of the polyester ink, as long as it is suitable for the ink of the polyester film 220.

Please refer to FIG. 3 and FIG. 4A simultaneously. FIG. 4A is a cross-sectional view of AA in the setting area 241 of FIG. 3. The polyester ink layer 240 is coated on the polyester film 220, and the second gold finger 221 is attached to the polyester. On the ink layer 240. In addition, the trace of the second circuit 225 and the second contact pad 222 are composed of a silver paste layer and a carbon film layer. Referring to FIG. 4B, a cross-sectional view of B-B of FIG. 3 is illustrated. The silver glue layer 402 is coated on the polyester film 220, and the carbon film layer 403 is overlaid on the silver glue layer 402 to form a protective layer to avoid oxidation of the silver paste. Since both the carbon film layer 403 and the silver paste layer 402 are electrically conductive materials, the traces of the second circuit 225 and the second contact pads 222 can be formed.

Referring to FIG. 4C, FIG. 4C is a schematic structural view of the conductive tape 230 of the present invention. The conductive tape 230 has a plurality of linear conductive regions 410. The linear conductive regions 410 are adhered to one side of the substrate 210 and one side of the polyester film 220 to be connected to the first gold finger 211 and the second gold finger 221. Since the linear conductive regions 410 on the conductive tape 230 are located on the same side of the conductive tape 230, the conductive tape 230 may be folded and disposed between the substrate 210 and the polyester film 220. One end of the conductive tape 230 is adhered to one side of the substrate 210, and the other end is adhered to one side of the polyester film 220 to electrically connect the first gold finger 211 and the second gold finger 221 . The first gold finger 211 and the second gold finger 221 can be electrically connected via the linear conductive region 410. The substrate 210 can obtain an electrical signal of the second circuit 225 on the polyester film 220 via the first gold finger 211. It is to be noted that the present invention can be fixed between the substrate 210 and the polyester film 220 by HMF heat pressing, but the present invention is not limited thereto.

Please refer to FIG. 5. FIG. 5 is a partial schematic diagram of a key sensing structure according to an embodiment of the present invention. The polyester film 210 forms an embossed portion 510 where the second contact pad 222 is disposed. The second contact pad 222 is also composed of a silver paste layer 402 and a carbon film layer 403. The second contact pad 222 is disposed on the inner side of the embossed portion 510 , and the first contact pad 212 is disposed on the substrate 210 and below the second contact pad 222 . The keys of the button unit 120 are correspondingly disposed above the embossed portion 510. When the button is pressed, the embossed portion 510 is recessed toward the substrate 210 due to the pressing force of the button, so that the second contact pad 222 contacts the first contact pad 212 to form a short circuit, as shown by the dotted line in FIG. 5(a). . The computer 100 can determine whether the button is pressed by detecting whether the second contact pad 222 and the first contact pad 212 are in contact with each other.

For the structure of the first contact pad 212 and the second contact pad 222, please refer to FIG. 5(b) and FIG. 5(c). The first contact pad 212, for example, a circular conductive copper foil, can be formed directly on the substrate 210 by a process of a printed circuit board, as shown in FIG. 5(b). The appearance of the second contact pad 222 may also be a circular carbon film formed on the polyester film 220. The present invention uses the first contact pad 212 and the second contact pad 222 to conduct whether the button is pressed, instead of using the second contact pad 222 to short the electrode on the substrate 210. Therefore, the substrate 210 does not need to be provided with staggered electrodes to indicate positive and negative electrodes. The first contact pads 212 on the substrate 210 can be a single circular pattern without the need to design multiple staggered pins. In addition, since the first contact pad 212 and the second contact pad 222 are both conductors, the entire loop can be turned on to complete the key input operation as long as there is any point contact. In other words, the first circuit 215 and the second circuit 225 can be turned on by the contact of the first contact pad 212 with the second contact pad 222, and the computer 100 can pass the signals on the first circuit 215 and the second circuit 225 ( For example, voltage changes) to determine what button the user is pressing.

In addition, it should be noted that the first circuit 215 and the second circuit 225 refer to a conductive line or a layout pattern connecting the first contact pad 212 and the second contact pad 222, which may be changed according to design requirements, and the embodiment does not have any limit. The patterns of the first contact pads 212 and the second contact pads 222 can also be adjusted according to design requirements, and the embodiment is not limited to FIG. 5. The connection relationship between the above components includes electrical connection directly or indirectly or in parallel, as long as the required electrical signal transmission function can be achieved, the embodiment is not limited. After the description of the above embodiments, those skilled in the art should be able to infer other embodiments, which are not described herein.

In summary, the button sensing structure of the present invention can improve the accuracy of button detection and can simplify the circuit design on the substrate, thereby improving the sensitivity of the button detection of the computer.

Although the preferred embodiments of the present invention have been disclosed as above, the present invention is not limited to the above-described embodiments, and any one of ordinary skill in the art can make some modifications without departing from the scope of the present invention. The scope of protection of the present invention should be determined by the scope of the appended claims.

100. . . computer

101. . . Ontology

110. . . Display unit

120. . . Button unit

200. . . Button sensing structure

210. . . Substrate

211. . . First golden finger

212. . . First contact pad

215. . . First circuit

220. . . Polyester film

221. . . Second golden finger

222. . . Second contact pad

225. . . Second circuit

230. . . Conductive tape

240. . . Polyester ink layer

241. . . Setting area

402. . . Silver layer

403. . . Carbon layer

410. . . Linear conductive area

510. . . Emboss

FIG. 1 is a schematic diagram of a computer according to an embodiment of the present invention.

FIG. 2 is a schematic diagram of a key sensing structure according to an embodiment of the present invention.

FIG. 3 is a schematic structural diagram of a key sensing structure 200 according to an embodiment of the present invention.

4A is a cross-sectional view of A-A in the setting area 241 of FIG. 3.

4B is a cross-sectional view of B-B of FIG. 3.

FIG. 4C is a schematic view showing the structure of the conductive tape 230 of the present invention.

FIG. 5 is a partial schematic view showing a key sensing structure according to an embodiment of the present invention.

210‧‧‧Substrate

221‧‧‧second golden finger

211‧‧‧ first golden finger

222‧‧‧Second contact pad

212‧‧‧First contact pad

225‧‧‧second circuit

215‧‧‧First circuit

230‧‧‧Conductive tape

220‧‧‧ polyester film

240‧‧‧ polyester ink

241‧‧‧Setting area

Claims (14)

A button sensing structure includes: a substrate having a first circuit and a plurality of first gold fingers, the first circuit having a plurality of exposed first contact pads; a polyester film disposed on the substrate Having a second circuit and a plurality of second gold fingers, the second circuit having a plurality of bare second contact pads corresponding to the first contact pads, wherein each of the second contact pads and the corresponding first one a gap between the contact pads; and a conductive tape adhered to one side of the substrate and one side of the polyester film for electrically connecting the first gold fingers and the second gold fingers; The polyester film has a setting area, and the setting area is coated with a polyester ink layer to set the second gold fingers, wherein the second gold fingers are disposed on the coated polyester ink layer . The button sensing structure of claim 1, wherein the conductive tape has a plurality of linear conductive regions, and the linear conductive regions are correspondingly connected to the first gold fingers and the second gold fingers, wherein The conductive tape is folded in half and disposed between the substrate and the polyester film. The button sensing structure of claim 1, wherein the first circuit and the second circuit are disposed face to face. The button sensing structure of claim 1, wherein the second gold fingers are correspondingly connected to the second contact pads. The button sensing structure of claim 1, wherein the substrate is coated with an insulating layer having a plurality of openings corresponding to the first contact pads to expose the first contact pads. Buttons as described in claim 1 or 2 or 3 or 4 or 5 The sensing structure, wherein the polyester film has a plurality of embossing portions, and the second contact pads are disposed on the inner side surfaces of the embossing portions. The button sensing structure of claim 1 or 2 or 3 or 4 or 5, wherein the second circuit trace and the second contact pads are respectively a silver paste layer and a carbon film layer The composition is characterized in that the silver glue layer is coated on the polyester film, and the carbon film layer is coated on the silver glue layer to cover the silver glue layer. A computer includes: a body having a display unit and a button unit; and a button sensing structure disposed in the body and located under the button unit, wherein the button sensing structure comprises: a substrate having a first a circuit and a plurality of first gold fingers, the first circuit has a plurality of exposed first contact pads; a polyester film disposed on the substrate and having a second circuit and a plurality of second gold fingers, The second circuit has a plurality of bare second contact pads corresponding to the first contact pads, wherein each of the second contact pads has a gap between the corresponding first contact pads; and a conductive tape is adhered to One side of the substrate and one side of the polyester film are used for electrically connecting the first gold fingers and the second gold fingers; wherein the polyester film has a setting area on the setting area A polyester ink layer is coated to set the second gold fingers, wherein the second gold fingers are disposed on the coated polyester ink layer. The computer of claim 8, wherein the conductive tape has a plurality of linear conductive regions, and the linear conductive regions are correspondingly connected to the first gold fingers and the second gold fingers, wherein the conductive tape is folded in half And disposed between the substrate and the polyester film. The computer of claim 8, wherein the first circuit and the second circuit are disposed face to face. The computer of claim 8, wherein the second gold fingers are correspondingly connected to the second contact pads. The computer of claim 8, wherein the substrate is coated with an insulating layer having a plurality of openings corresponding to the first contact pads to expose the first contact pads. The computer of claim 8 or 9 or 10 or 11 or 12, wherein the polyester film has a plurality of embossing portions, and the second contact pads are disposed correspondingly to the embossing portions. side. The computer of claim 8 or 9 or 10 or 11 or 12, wherein the trace of the second circuit and the second contact pads are respectively composed of a silver paste layer and a carbon film layer, wherein The silver glue layer is coated on the polyester film, and the carbon film layer is coated on the silver glue layer to cover the silver glue layer.