Capacitive touch panel and electronic equipment

Abstract

The utility model provides a capacitive touch panel and electronic equipment, the panel comprises a face shell, an electric suppressor and a circuit board, the first end of the electric suppressor is electrically connected with the face shell, and the second end of the electric suppressor is connected with the ground of the circuit board. When a human hand touches the face shell with large static electricity, most of instantaneous large current generated by electrostatic discharge reaches the electric suppressor through the face shell, then reaches the ground wire on the circuit board through the electric suppressor and then is discharged through the ground wire on the circuit board, so that the problems of device hard failure and function soft failure caused by static electricity are avoided.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of touch control, and in particular to a capacitive touch panel and an electronic device. BACKGROUND

[0002] The capacitive touch panel generally comprises a face shell and a circuit board. When a human hand does not contact the face shell, there is a capacitance (stray capacitance) between the face shell and the circuit board. When the human hand touches the face shell, a parasitic capacitance is generated between the hand and the face shell, which increases the capacitance between the face shell and the circuit board, resulting in an increase in charging time. When the increased time exceeds a preset value, the circuit board determines that a human hand touch operation is performed, thereby generating a corresponding operation to achieve touch control. This requires that the face shell cannot be grounded. However, when static electricity is generated in the human body, the human hand touching the metal face shell will generate a large instantaneous current due to static discharge, which affects the normal operation of the circuit board, such as causing the touch panel to fail, causing the secondary power jump of the circuit board to damage components, and the like.

[0003] The prior art increases the distance between the face shell and the circuit board, so that the static electricity cannot be injected into the inside of the panel. However, this still has the problem of static electricity protection failure, such as when static electricity is generated in the human body, causing the touch function of the panel to fail, the key to have no response, and in severe cases, causing the device of the panel to fail hard. Moreover, increasing the distance between the face shell and the circuit board also causes the panel to occupy a larger space, which is not conducive to space saving. Practical new type content

[0004] Therefore, the present application provides a capacitive touch panel and an electronic device to solve the above problems by using an electric suppressor.

[0005] In a first aspect, the present application provides a capacitive touch panel, comprising a face shell, an electric suppressor, and a circuit board (PCB), wherein the first end of the electric suppressor is electrically connected to the face shell, and the second end is connected to the ground (GND) of the circuit board. The face shell can be a metal face shell, or a non-metal face shell coated with a conductive coating (i.e., a conductive layer), such as a glass face shell coated with a polyethylene terephthalate (PET) layer or an indium tin oxide (ITO) layer, or a metal face shell coated with a non-conductive coating or other material. The electric suppressor is a device for limiting current or voltage, and the first end represents one end of the two ends of the electric suppressor, and the second end represents the other end. For example, the electric suppressor can be a varistor, a surge suppressor, or the like. Figure 1As shown, when a human hand carries the static electricity and touches the surface shell, the instantaneous large current generated by the static discharge is mostly discharged through the surface shell to the electrical suppressor, and then discharged through the ground wire on the circuit board to the ground wire on the circuit board, thereby avoiding the hard failure and soft failure of the device caused by static electricity. Moreover, the electrical suppressor and the human hand touch panel have the same level, and the sensitivity of the panel is not affected. The capacitive touch panel provided by the embodiment of the application does not need to increase the distance between the surface shell and the circuit board, thereby avoiding occupying more space and being conducive to product miniaturization. Moreover, in the normal case without static electricity, the panel can still work normally when the human hand contacts the surface shell without being affected by the electrical suppressor, and in the case with static electricity, the static electricity is discharged through the electrical suppressor path. Therefore, the capacitive touch panel provided by the embodiment of the application can effectively resist static electricity.

[0006] The electrical suppressor can be a transient voltage suppressor (TVS) or a capacitor. When the electrical suppressor is a capacitor, the cost of the capacitive touch panel for resisting static electricity can be reduced.

[0007] Preferably, when the junction capacitance value of the TVS is in the pico-farad (pF) level or the capacitance value of the capacitor is in the pF level, the capacitive touch panel provided by the embodiment of the application can have an anti-static capability of up to 10 kilovolts (KV) while ensuring the touch sensitivity of the panel.

[0008] Optionally, the electrical suppressor can further include a resistor, so as to reduce the electrostatic discharge (ESD) energy passing through the electrical suppressor when a human hand touches the surface shell in a normal case, thereby effectively protecting the circuit board.

[0009] Optionally, the surface shell can be electrically connected to the electrical suppressor through an electrical connecting piece.

[0010] Preferably, the circuit board is provided with an electrical contact portion, the electrical suppressor is located on the circuit board and electrically connected to the electrical contact portion, and the surface shell is connected to the circuit board through the electrical connecting piece, and the electrical connecting piece is electrically connected to the electrical contact portion, thereby achieving the purpose of electrically connecting the surface shell and the electrical suppressor, and being conducive to maintaining the relative position between the surface shell and the circuit board. It can be understood that the electrical contact portion is not in contact with the remaining circuit portion on the circuit board except for being connected to the electrical suppressor.

[0011] Optionally, the electrical connecting piece can include a metal spring pin, a screw, a screw boss, a pogo pin, or conductive foam, etc. The screw boss is a guide structure of the screw, including a screw column and a tight-fitting column.

[0012] Optionally, the electrical connector can be directly connected to the electrical suppressor, for example, one end of the electrical suppressor is connected to the ground wire on the circuit board, and the other end is in electrical contact with the electrical connector.

[0013] Optionally, the electrical contact part can be a copper sheet, for example, a copper leakage part on the circuit board, which is electrically connected to the ground wire on the circuit board through the electrical suppressor.

[0014] Optionally, the electrical contact part can also be a tin sheet, for example, a part of the copper leakage part plated with tin, or a gold sheet, for example, a part of the circuit board in contact with the electrical connector is plated with a layer of gold, or a layer of other metal on the circuit board as the electrical contact part.

[0015] Optionally, the capacitive touch panel can be a switch panel, a scene panel, etc.

[0016] In the second aspect, the embodiments of the present application also provide an electronic device comprising the capacitive touch panel of any one of the first aspect, and the electrical suppressor is used to improve the anti-static capability of the electronic device. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0018] Figure 1 a is a structural schematic diagram of a capacitive touch panel provided by the present application;

[0019] Figure 2 a is a structural schematic diagram of a capacitive touch panel provided by the present application;

[0020] Figure 2 b is a schematic diagram of the static discharge path of the embodiment shown in a; Figure 2

[0021] Figure 3 a is a schematic diagram of a spring provided by the embodiments of the present application;

[0022] Figure 3 b is a schematic diagram of a spring needle provided by the embodiments of the present application;

[0023] Figure 3 c is a schematic diagram of conductive foam provided by the embodiments of the present application;

[0024] Figure 3 d is a schematic diagram of conductive cloth provided by the embodiments of the present application; ​

[0025] Figures 4a to 4d Electrical connection diagrams for four different electrical suppressors provided in embodiments of this application;

[0026] Figures 5a to 5d Electrical connection diagrams for four other different electrical suppressors provided in embodiments of this application;

[0027] Figure 6 This is a schematic diagram of the structure of the second embodiment of the capacitive touch panel provided in this application;

[0028] Figure 7a This is a schematic diagram of the structure of the third embodiment of the capacitive touch panel provided in this application;

[0029] Figure 7b for Figure 7a A schematic diagram of the electrical contact portion in the illustrated embodiment;

[0030] Figure 7c for Figure 7a Another schematic diagram of the electrical contact portion in the illustrated embodiment;

[0031] Figure 7d for Figure 7a A schematic diagram of the electrical connection between the electrical contact and the electrical suppressor on the circuit board in the illustrated embodiment;

[0032] Figure 8 A schematic diagram of the structure of an embodiment of the electronic device provided in this application. Detailed Implementation

[0033] To better understand the technical solution of this application, the embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0034] First Embodiment

[0035] like Figure 2 As shown in Figure a, the capacitive touch panel includes a metal housing 21, an electrical connector 24, a circuit board 22, and an electrical suppressor 23. The electrical connector 24 can be a screw, a spring-loaded pin (such as...). Figure 3 As shown in a), spring pin (as shown in a) Figure 3 (as shown in b), conductive foam (such as...) Figure 3 As shown in c), conductive cloth (such as...) Figure 3 (as shown in d), or screws, etc.

[0036] The circuit board 22 has an electrical contact 221, which may be made of copper. The circuit board 22 can be considered to include two separate grounds, one of which, with a smaller area, can be considered the electrical contact 221. The metal casing 21 is electrically connected to the electrical contact 221 via an electrical connector 24. Thus, large static charges on the metal casing 21 can reach the electrical contact 221 through the electrical connector 24.

[0037] The electrostatic suppressor 23 is connected to the circuit board 22 at one end and to the ground of the circuit board 22 at the other end. In this way, static electricity reaching the electrical contact 221 can be discharged through the electrostatic suppressor 23 to the ground of the circuit board 22 and through the ground of the circuit board 22. Alternatively, the electrostatic suppressor 23 is a TVS, and the circuit connection relationship of the TVS on the circuit board 22 is as shown in Figure 4a Alternatively, the electrostatic suppressor 23 is a capacitor, and the circuit connection relationship of the capacitor is as shown in Figure 4b Alternatively, the electrostatic suppressor 23 includes a TVS and a resistor, and the circuit connection relationship of the TVS and the resistor is as shown in Figure 4c Alternatively, the electrostatic suppressor 23 includes a capacitor and a resistor, and the circuit connection relationship of the capacitor and the resistor is as shown in Figure 4d Alternatively, the electrostatic suppressor 23 includes a capacitor and a resistor, and the circuit connection relationship of the capacitor and the resistor is as shown in

[0038] When the metal shell receives static electricity, the discharge path of the static electricity is as shown in Figure 2 b. Figure 2 b. A represents the metal shell, B represents the electrical contact, and C represents the ground of the circuit board. It can be seen that the capacitive touch panel provided in the embodiment can guide static electricity on the metal shell to the electrical contact through the conductive mode of the electrical connector, and then to the ground of the circuit board through the connection medium, such as a TVS with a small junction capacitance, a capacitor, a TVS+resistor, or a capacitor+resistor, so that the static electricity energy can be discharged through the ground (GND) of the circuit board. The capacitive touch panel can avoid product failure caused by secondary static electricity and improve the protection level of static electricity while ensuring product miniaturization and not affecting the function.

[0039] The aforementioned capacitive touch panel may further include one or more of the following: a touch-sensing layer, conductive adhesive, a flexible printed circuit board (FPC), a transparent medium, a plastic frame / support, an adhesive, a sealant, and an anti-glare coating. The touch-sensing layer is located between the metal casing and the FPC, and is used to sense capacitance changes generated when a finger or other conductor approaches or touches the panel. The FPC is located between the touch-sensing layer and the circuit board, and is used to transmit the touch signal (capacitance change) sensed by the touch-sensing layer to the circuit board. The conductive adhesive may be filled between the touch-sensing layer and the FPC, and is used to transmit the touch signal from the touch-sensing layer to the FPC, providing a stable electrical connection. The touch-sensing layer may include two transparent sheets with specific transparent conductive patterns, used to sense capacitance changes generated when a finger or other conductor approaches or touches the panel. The transparent medium may be filled between the two transparent sheets to prevent the two transparent sheets from conducting to each other. This transparent medium may be air, a plastic film, or other transparent materials. The plastic frame / support, adhesive, and sealant are used to fix the various parts of the aforementioned capacitive touch panel, wherein the plastic frame / support also provides support. Anti-glare coatings can be applied to metal surfaces to prevent glare and improve the user experience.

[0040] When the aforementioned capacitive touch panel includes one or more of the following components: a touch sensing layer, conductive adhesive, and a flexible circuit board, electrical connectors should avoid these components to prevent static electricity from damaging them.

[0041] The aforementioned capacitive touch panel can be a switch panel, a scene panel, etc. When the aforementioned capacitive touch panel is a switch panel, the aforementioned circuit board may further include one or more functions such as power supply control and light switching. When the aforementioned capacitive touch panel is a scene panel, the aforementioned circuit board may further include one or more functions such as scene control, dimming control, and linkage with other devices.

[0042] Optionally, the shape of the electrical contact portion in the capacitive touch panel is not limited. It can be elliptical, circular, square, hexagonal, ring-shaped, pentagonal, or irregular in shape, as long as it can electrically connect the metal shell to the electrical suppressor.

[0043] As a variation of the aforementioned capacitive touch panel, another feasible approach is that the capacitive touch panel includes multiple sets of the aforementioned electrical contacts and electrical suppressors, with each set including one of the aforementioned electrical contacts and one of the aforementioned electrical suppressors, in order to further improve the antistatic capability.

[0044] like Figures 5a to 5d As shown, the aforementioned capacitive touch panel includes four sets of electrical contacts and an electrical suppressor. Each set of electrical contacts is a ring-shaped copper foil 2212. The difference lies in... Figure 5aThe four groups of electrical suppressors shown are TVSD2000, D2001, D2002, and D2003, respectively. Figure 5b The four groups of capacitors shown are C2000, C2001, C2002, and C2003, respectively. Figure 5c The four groups shown are connected TVS and resistors: D2000+R2000, D2001+R2001, D2002+R2002, and D2003+R2003. Figure 5d The four groups of capacitors shown are connected capacitors and resistors: C2000+R2000, C2001+R2001, C2002+R2002, and C2003+R2003.

[0045] Another feasible approach is that when the capacitive touch panel includes multiple sets of electrical contacts and suppressors, the electrical contacts in each set can be different, and the suppressors in each set can also be different. For example, the capacitive touch panel may include two sets of electrical contacts and suppressors, where one set has circular copper contacts and the other set has square gold contacts; one set may have a TVS suppressor and the other set may have a connected capacitor and resistor, and so on. This is merely an example and not a limitation; the number (sets) of electrical contacts and suppressors, the material and shape of the electrical contacts, and the components used in the suppressors (such as TVS, capacitors, or resistors) can be set according to actual needs.

[0046] Second Embodiment

[0047] like Figure 6 As shown, the difference between the capacitive touch panel 60 and the above-described capacitive touch panel embodiment is that the electrical connector is a screw bolt 64, and the electrical contact portion on the circuit board 22 is a copper foil 621.

[0048] Third Embodiment

[0049] like Figure 7a As shown, the difference between the capacitive touch panel 70 and the above-described capacitive touch panel embodiment is that it includes a metal casing 71, a circuit board 72, and a TVS 73 (as shown). Figure 7d (As shown), screw 74 and plastic bracket 75. In this embodiment, screw 74 is non-conductive.

[0050] The lower surface of the metal housing 71 is provided with screw bolts 711. The metal housing 71, screw bolts 711, and circuit board 72 form a sandwich structure, and the three are locked together by screws 74. The screw bolts 711 contact the electrical contacts on the circuit board 72. The electrical contacts on the circuit board 72 are solder pads 7212 (e.g., solder mask 7212) applied to the circuit board using a copper-slip soldering method. Figure 7b(As shown), this makes the electrical connection between the metal casing 71 and the TVS 73 more reliable. The exposed copper 7211 covered by the tin foil 7212 is as follows... Figure 7c As shown, to ensure the normal capacitive touch function of the capacitive touch panel 70, the copper trace around the screw holes 723 on the circuit board 72 is separated from the ground (GND) copper trace. For example... Figure 7d As shown, the copper foil around the screw hole 723 and GND are connected using TVS 73 (junction capacitance in the pF range).

[0051] like Figure 7d As shown, the solder pad 7212 (or copper pad 7211) is electrically connected to a solder joint 731 of the TVS via a conductor 722 on the circuit board. The conductor 722 is electrically connected to either the copper pad 7211 or the solder pad 7212 (which may be on the same layer or a different layer). The remaining solder joints 732 of the TVS 73 are electrically connected to ground (GND) on the circuit board 72. When electrostatic energy is injected, the static electricity will cause the TVS 73 to conduct momentarily, introducing the electrostatic energy into the GND of the circuit board 72, and finally dissipating it through the power line or the power grid.

[0052] The capacitive touch panel provided in the above embodiments of this application reduces electrostatic discharge (ESD) energy by using capacitors (+resistors), TVS (+resistors), and other electrical suppressors at the electrostatic feed point (such as a metal casing, electrical connector, or electrical contact), and then discharges the electrostatic energy through a single-board GND, thereby doubling the antistatic capability. This is beneficial for the continuous development of capacitive touch panels towards miniaturization and metallization.

[0053] The electronic devices provided in this application may be air conditioners, water heaters, smart lights, TV remote controls, range hoods, water purifiers, ovens, robots, microwave ovens, pressure cookers, air fryers, and other electronic devices that need to be controlled via a panel, or industrial electronic devices.

[0054] For example, an embodiment of an electronic device provided in this application, such as Figure 8 As shown, the device includes a control panel 81 and functional components 82. The control panel 81 is any of the capacitive touch panels provided in the above embodiments. The functional components 82 can be components with air conditioning functions, or components with hot water functions, light-emitting functions, television control functions, fume extraction functions, water purification functions, food grilling functions, intelligent operation functions, microwave heating functions, high-pressure food heating functions, or processing, manufacturing, or communication functions, etc. The electronic device provided in this application, by using a control panel with high anti-static capability and miniaturization, can improve the anti-static capability of the electronic device and also facilitates the miniaturization of the electronic device.

[0055] The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in the description of the application and the appended claims, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be understood that the terms "and / or", "at least one of", "one or more" and "and / or" as used herein refer to and encompass any possible combination of one or more of the associated listed items, including any possible combinations of replacements of items by other items from the associated list. It will be further understood that the terms "comprises" and / or "comprising", or "includes" and / or "including" when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, and / or groups thereof.

[0056] It should be apparent that the described embodiments of the application are only some embodiments and not all embodiments of the application. Based on the embodiments described herein, one of ordinary skill in the art will be able to devise all other embodiments of the application without undue experimentation, which are within the scope of the application.

Claims

1. A capacitive touch panel, characterized by, The capacitive touch panel comprises a face shell, an electrical suppressor and a circuit board, a first end of the electrical suppressor is electrically connected with the face shell, and a second end of the electrical suppressor is connected with the ground of the circuit board.

2. Panel according to claim 1, characterized in that The electrical suppressor comprises a transient voltage suppressor (TVS) or a capacitor.

3. Panel according to claim 2, characterized in that The junction capacitance of the TVS is in the order of picofarad.

4. The panel of claim 2, wherein, The capacitance of the capacitor is in the order of picofarad.

5. The panel of claim 2, wherein, The electrical suppressor further comprises a resistor.

6. Panel according to any of claims 1 to 5, characterized in that The face shell is further electrically connected with the electrical suppressor through an electrical connector.

7. Panel according to claim 6, characterized in that The circuit board is provided with an electrical contact part; the electrical suppressor is located on the circuit board, a first end of the electrical suppressor is electrically connected with the face shell through the electrical contact part; the face shell is connected with the circuit board through the electrical connector, and the electrical connector is in electrical contact with the electrical contact part.

8. The panel of claim 6, wherein, The electrical connector comprises a metal spring pin, a screw, a screw bolt, a spring needle, a conductive cloth or a conductive foam.

9. The panel of claim 7, wherein, The electrical contact part is a copper sheet, a tin sheet or a gold-plated sheet on the circuit board.

10. Panel according to any of claims 1 to 5, characterized in that The capacitive touch panel is a switch panel or a scene panel.

11. Panel according to any of claims 1 to 5, characterized in that The face shell is a metal face shell or a non-metal face shell coated with a conductive layer.

12. An electronic device, comprising: The capacitive touch panel comprises any one of the capacitive touch panels in claims 1 to 11.

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