CN202737844U

CN202737844U - Touch keys

Info

Publication number: CN202737844U
Application number: CN 201220305089
Authority: CN
Inventors: 陆舟; 于华章
Original assignee: Feitian Technologies Co Ltd
Current assignee: Feitian Technologies Co Ltd
Priority date: 2012-06-26
Filing date: 2012-06-26
Publication date: 2013-02-13
Anticipated expiration: 2022-06-26

Abstract

The utility model relates to touch keys, which comprise a touch panel, keys, signal ends, and an active shielding layer, wherein the keys and the signal ends are distributed on a printed circuit board (PCB); the active shielding layer is distributed around the keys; and the signal ends are respectively electrically connected with the keys and the active shielding layer. By means of the active shielding layer, influence of induction capacitance among each key and influence of induction capacitance formed by the outside noise on the keys can be lessened, and therefore precision of touch induction of the keys can be improved.

Description

Touch key

Technical Field

The utility model relates to a button wiring structure, in particular to capacitive touch button's wiring structure.

Background

Compared with the traditional mechanical key, the capacitive touch sensing key is attractive, durable and long in service life, and because the capacitive touch screen needs to sense the current of a human body, the capacitive touch screen can only be operated by the human body and is not easy to touch by mistake, and the application of the touch key is increasingly wide.

The capacitive touch sensing key is only a small copper-clad pad on a PCB (printed circuit board), and forms a sensing capacitor with surrounding ground signals, a human body touches the key through an insulated touch panel to influence the capacitance value, and whether the corresponding key is pressed down can be judged according to the change of physical quantity related to the capacitance value, so that if a plurality of touch keys are distributed at a short distance or the key is adjacent to other circuits or devices with stronger electric signals, the interference of peripheral noise influences the sensing capacitor value formed by the key, and the accuracy of judging whether the key is pressed down is reduced.

SUMMERY OF THE UTILITY MODEL

For solving the problem that exists among the prior art, according to the utility model discloses an aspect provides a touch button, include: the touch panel, the keys and the signal ends are distributed on the PCB, the signal ends are electrically connected with the keys, and the touch panel is tightly attached to the tops of the keys;

the PCB board comprises an active shielding layer, and the active shielding layer is distributed around the touch keys.

The touch keys comprise at least two keys, the signal ends comprise different signal input detection ends, and each signal input detection end is electrically connected with each key.

The active shielding layer is coated with copper, the coated copper is connected into a whole and distributed around each key, and the distance between the coated copper and the edge of each key is larger than or equal to 1 mm. The active shielding layer bypasses the wiring connecting each key and the signal input detection end, and the distance between the active shielding layer and the wiring is larger than or equal to 1 mm.

The signal end comprises a signal input end which is electrically connected with the active shielding layer and used for inputting an electric signal to the active shielding layer.

Furthermore, the key is a copper-clad or bonding pad, and the shape of the key is circular or rectangular;

when the key is circular, the key is a circular key with the diameter larger than or equal to 10 mm;

when the key is rectangular, the key is a rectangular key with the short side larger than or equal to 10 mm.

The thickness range of the touch panel is 1 mm-2.5 mm; and within the thickness range of the touch panel, the thickness of the touch panel is positively correlated with the size of the key.

The PCB board comprises a covering layer;

the coverage layer is distributed on the front surface of the PCB, and the distance between the coverage layer and the edge of the active shielding layer is greater than or equal to 1 mm;

or,

the covering layer is distributed on the back of the PCB, and the thickness of the substrate of the PCB is larger than or equal to 1 mm.

According to another aspect of the present invention, a touch key device is provided, which includes a key module, an active shielding module, and a signal module, wherein the signal module includes a signal detection unit, a judgment unit, and a signal input unit;

the signal input unit is connected with the key module and inputs an electric signal for the key module; the signal detection unit is connected with the key module and used for detecting the electric signals of the keys in real time, and the judgment unit is connected with the signal detection unit and used for judging whether the keys are pressed down according to the detection result of the signal detection unit.

The signal input unit is connected with the active shielding module and inputs an electric signal for the active shielding module.

Furthermore, the touch screen comprises a grounding module which is used for forming an induction capacitor with the key module.

Through the utility model provides a wiring structure of touch button makes the initiative shielding layer that distributes around the touch button, weakens the influence of touch button by external noise through the initiative shielding layer, weakens the touch button simultaneously and to external influence, improves the precision of touch button.

Drawings

Fig. 1 is a circuit structure diagram of a touch key provided in embodiment 1 of the present invention;

fig. 2 is a partially enlarged circuit diagram of a touch key according to embodiment 1 of the present invention;

fig. 3 is a cross-sectional structure view of a touch key provided in embodiment 1 of the present invention;

fig. 4 is a touch key device provided in embodiment 2 of the present invention.

Detailed Description

The present invention will be further described with reference to the accompanying drawings and specific embodiments, but the present invention is not limited to the following embodiments.

Example 1

Referring to fig. 1, in embodiment 1, three parallel keys are taken as an example, and a touch key is provided, which includes: the keys 11 comprise a first key, a second key and a third key; an active shielding layer 12; the signal end 13 comprises a first signal input detection end, a second signal input detection end, a third signal input detection end and a first signal input end; and the above all are distributed on the PCB board 14, and also include a touch panel 15;

fig. 2 is an enlarged view of the first key of fig. 1 (i.e., the leftmost key of fig. 1), and fig. 3 is a cross-sectional view of the first key of fig. 2 cut at the position of the diametrical length line.

Referring to fig. 3, the touch panel 15 is located on the top of the keys, and is closely attached to the first key, the second key and the third key, so as to insulate the keys from the outside, and display the positions of the keys for the user to select. The thickness range of the touch panel 15 is 1 mm-2.5 mm.

The touch panel 15 is made of a material having excellent insulating properties, such as glass or a transparent acrylic plate.

The first key, the second key and the third key are distributed on the PCB and are respectively and electrically connected with the first signal input detection end, the second signal input detection end and the third signal input detection end to form three capacitive touch keys;

preferably, the first key, the second key and the third key are pads or copper-clad, and the shape of the key may be any shape, such as circular, rectangular, etc., particularly, if the key is a rectangular key, it is preferably a rectangular key with a short side length of 10mm or more, and this embodiment takes the key as a circular key with a diameter of 10mm or more as an example.

Preferably, in the present embodiment, the thickness of the touch panel 15 is positively correlated with the size of the key within the allowable range.

The first signal input detection end, the second signal input detection end and the third signal input detection end are respectively used for inputting electric signals to keys connected with the first signal input detection end, detecting the electric signals of the keys connected with the first signal input detection end in real time, and judging whether the keys connected with the first signal input detection end are pressed down or not according to detection results;

preferably, in this embodiment, the first signal input detection end, the second signal input detection end and the third signal input detection end are real-time consistent for the electrical signals input by each key.

The active shielding layer 12 is distributed around the key, and is electrically connected with the first signal input end by winding the wiring of the electrical connection key and the signal input detection end connected with the electrical connection key;

preferably, in this embodiment, the active shielding layers around the keys are connected into a whole, and the first signal input terminal inputs an electrical signal to the active shielding layers;

preferably, in this embodiment, the active shielding layer is copper-clad, and referring to fig. 2, the distance from the edge of each of the first key, the second key and the third key is greater than or equal to 1mm, and the distance from the trace between each of the keys and the signal input detection end is greater than or equal to 1 mm;

the first signal input end is used for providing an electric signal for the active shielding layer;

preferably, in this embodiment, the electrical signal provided by the first signal input end for the active shielding layer is consistent with the electrical signals provided by the first signal input detection end, the second signal input detection end and the third signal input detection end for the keys in real time, so as to generate a shielding electric field, reduce mutual interference between the electric fields generated by the keys, and improve the key sensitivity.

Preferably, in this embodiment, referring to fig. 2, the back side or the front side of the PCB may further include a ground layer, and particularly, when the ground layer is on the back side of the PCB, the thickness of the PCB substrate is not less than 1 mm; when the cover stratum is arranged on the front surface of the PCB, the distance between the cover stratum and the edge of the shielding layer is larger than or equal to 1 mm.

Example 2

Referring to fig. 4, the present embodiment 2 provides a touch key device including: the signal module 24 comprises a signal detection unit 241, a judgment unit 243 and a signal input unit 242;

the grounding module 21 is used for providing a grounding signal and forms an induction capacitor with the key module 22;

the key module 22 is connected with the signal module 24;

the active shielding module 23 is connected to the signal input unit 242;

the signal module 24 is configured to provide an input signal for the key module 22 and the active shielding module 23 and detect the signal, and includes a signal detection unit 241, a determination unit 243, and a signal input unit 242;

the signal input unit 242 is connected to the key module 22 and the active shielding module 23, and provides real-time consistent electrical signals for the key module 22 and the active shielding module 23;

the signal detection unit 241 is electrically connected with the key module 22; for detecting circuit signals in real time;

the judging unit 243 is connected with the signal detecting unit 241 and judges whether the key is pressed according to the detection result of the signal detecting unit;

the touch panel module 25 is in close contact with the key module 22, and displays each key position for the user to select and press.

Claims

1. A touch key, comprising: the touch panel, the keys and the signal ends are distributed on the PCB, the signal ends are electrically connected with the keys, and the touch panel is tightly attached to the tops of the keys;

2. The touch key of claim 1, wherein the touch key comprises at least two keys, the signal terminals comprise different signal input detection terminals, and each signal input detection terminal is electrically connected to each key.

3. The touch key of claim 1, wherein the active shielding layer is copper clad, the copper clad being integrally distributed around each key at a distance greater than or equal to 1mm from an edge of each key.

4. The touch security key of claim 3, wherein the active shielding layer bypasses traces connecting each key and the signal input detection end, and has a distance greater than or equal to 1mm from the traces.

5. The touch key of claim 1, wherein the signal terminal comprises a signal input terminal electrically connected to the active shielding layer for inputting electrical signals to the active shielding layer.

6. The touch key of claim 1, wherein the key is copper clad or solder pad, the key being circular or rectangular in shape;

7. The touch key of claim 1, wherein the touch panel has a thickness in a range of 1mm to 2.5 mm; and within the thickness range of the touch panel, the thickness of the touch panel is positively correlated with the size of the key.

8. The touch key of claim 1, wherein the PCB board includes a coverlay layer thereon;

or,

9. A touch key device is characterized by comprising a key module, an active shielding module and a signal module, wherein the signal module comprises a signal detection unit, a judgment unit and a signal input unit;

10. The touch key device of claim 9, wherein the signal input unit is connected to the active shielding module to input an electrical signal to the active shielding module.

11. The touch key device of claim 10, comprising a grounding module for forming an inductive capacitance with the key module.