CN101888235B

CN101888235B - Projection touch key

Info

Publication number: CN101888235B
Application number: CN2010102186083A
Authority: CN
Inventors: 龙涛; 陶冬冬; 姚理觉; 刘江澜
Original assignee: Jiangsu Huitong Group Co Ltd
Current assignee: Jiangsu Huitong Group Co Ltd
Priority date: 2010-06-30
Filing date: 2010-06-30
Publication date: 2012-05-23
Anticipated expiration: 2030-06-30
Also published as: CN101888235A

Abstract

The invention discloses a projection touch key. The key comprises a key projection module, a capacitor field intensity detection module and a control module, wherein the key projection module comprises an operation panel, a circuit board, at least one real key and an operation key corresponding to the real key; a 0-90 degrees of angle is formed between the operation panel and the circuit board; the real key is arranged on the circuit board, the operation key is arranged on the operation panel, the operation key is in the projection region of the real key on the operation panel, and the distance between the real key and the operation key is less than 20cm. the real key is connected with the input end of the capacitor field intensity detection module, the output end of the capacitor field intensity detection module is connected with the input end of the control module, the capacitor field intensity detection module detects the change of capacitor field intensity between the real key and the operation key and transmits the change to the control module, and the control module performs key-press processing. By using the projection touch key, the separation of the key operation panel and the printed circuit board (PCB) can be realized.

Description

Projection touch key

Technical field

The present invention relates to a kind of touch key-press, relate in particular to a kind of projection type capacitance touch key-press, belong to the touch key-press technical field.

Background technology

Touch-key has developed for many years, that the guidance panel of touch sensible has is firm, wear-resistant, can insulation, the advantage of dust-separation, water proof, and its good looking appearance is novel.But because cost and stable aspect, just begin on electronic equipment popularly in a large number until in recent years, particularly in some home appliances, the advantage of touch key-press is more obvious, becomes hot technology in recent years.Adopted capacitance induction principle by the capacitance type touch key of extensive employing at present, insulating properties material shell such as the glass of penetrable 15mm thickness, plastics and detect the touch of finger.Capacitance type touch key mostly adopts man-machine interaction mode, and promptly the operator triggers button work with direct contact of finger and PCB circuit board key bits corresponding, and this just causes long touch wearing and tearing easily, thereby influences the useful life of button.Simultaneously existing touch sensible key panel back is the connection processing circuit directly, and the production technological requirement is high, and key panel or circuit board keep in repair, change trouble, poor expandability.The more important thing is that people are when paying close attention to the electronics and IT products quality; More and more pursue the fashion of modern science and technology product and attractive in appearance; If can make the guidance panel of touch key-press transparent; And the button pattern of fashion attractive in appearance is set on transparent panel, must satisfies the pursuit of user, thereby excite its interest and demand product to modern science and technology product fashion, novelty.But existing touch sensible key panel back is connection processing circuit PCB directly, can't solve the technical problem of the transparent button operation panel of exploitation.

Summary of the invention

The object of the present invention is to provide a kind of projection touch key, realize separating of button operation panel and PCB circuit board, it realizes the identification of button through the size that changes actual key position and operation push-button interdigit capacitor field intensity.

The object of the invention is achieved through following technical scheme:

A kind of projection touch key comprises button projection module 1, capacitor field intensity detection module 2, control module 3; Said button projection module 1 comprises operation panel 4, circuit board 5; Also comprise at least one actual key position 6 and the operation push-button position 7 corresponding with each actual key position 6; Operation panel 4 is by the non-conducting material manufacturing, and said operation panel 4 has angle with circuit board 5, and the scope of angle is 0 °～90 °; Said actual key position 6, capacitor field intensity detection module 2, control module 3 are positioned on the circuit board 5; Operation push-button position 7 is positioned on the operation panel 4, and operation push-button position 7 is in the view field of actual key position 6 on operation panel 4, and the distance of said actual key position 6 and operation push-button position 7 is less than 20 centimetres; Said actual key position 6 links to each other with the input of capacitor field intensity detection module 2; The output of capacitor field intensity detection module 2 links to each other with the input of control module 3; Capacitor field intensity detection module 2 detects the variation of capacitor field intensity between actual key position 6 and the operation push-button position 7; And sending variable quantity to control module 3, the button that control module 3 is correlated with is handled.

The object of the invention can also further realize through following technical measures:

Aforementioned a kind of projection touch key, the 6 conplane outsides are provided with shading ring 8 in the actual key position.

Aforementioned a kind of projection touch key, wherein capacitor field intensity detection module 2 uses special-purpose capacitance touch IC chip.

Compared with prior art, the invention has the beneficial effects as follows: realize separating of button operation panel and PCB circuit board, thereby reduce the manufacturing process requirement to touch-screen, key panel or circuit board keep in repair, change easy.Can trigger button in the space during use, let the user produce fresh, magical operating experience.

Description of drawings

Fig. 1 is a circuit structure diagram of the present invention;

Fig. 2 is a button projection module structure chart of the present invention;

Fig. 3 is a single IC chip capacity field intensity scanning circuit structure chart of the present invention;

Fig. 4 is a plurality of IC chip capacity field intensity scanning circuit structure chart of the present invention.

Embodiment

Below in conjunction with accompanying drawing and specific embodiment the present invention is described further.

As shown in Figure 1, the present invention includes button projection module 1, capacitor field intensity detection module 2, control module 3.As shown in Figure 2, said button projection module 1 comprises operation panel 4, circuit board 5, also comprises several actual key positions 6 and the operation push-button position 7 corresponding with each actual key position 6.Present embodiment has six actual key positions and corresponding operation push-button position, is respectively applied for volume increase and decrease, channel selection, power supply control, the menu control function of control television set.Said operation panel 4 forms an angle with circuit board 5, and the present embodiment angle is 45 °.Said actual key position 6, capacitor field intensity detection module 2, control module 3 are installed on the circuit board 5; Actual key position 6 is made by electric conductor; For preventing the phase mutual interference between a plurality of buttons, be provided with shading ring 8 in each 6 outside, actual key position, be installed on the circuit board 5.Operation push-button position 7 is positioned on the operation panel 4, and operation push-button position 7 is in the view field of actual key position 6 on operation panel 4, and present embodiment operation panel 4 is by transparent polymethyl methacrylate manufacturing, and operation push-button position 7 is printed on corresponding button sign.Said actual key position 6 is 10 centimetres with the distance of operation push-button position 7.Said structure has been realized separating of button operation panel and PCB circuit board.Said actual key position 6 links to each other with the input of capacitor field intensity detection module 2; The output of capacitor field intensity detection module 2 links to each other with the input of control module 3; Capacitor field intensity detection module 2 detects the variation of capacitor field intensity between actual key position 6 and the operation push-button position 7; And sending variable quantity to control module 3, the button that control module 3 is correlated with is handled.Capacitor field intensity detection module 2 uses special-purpose capacitance touch IC chip in the present embodiment, and said control module 3 is a MCU chip, has the interface that carries out serial asynchronous communication.As shown in Figure 1; When using, the user directly do not contact actual key position 6, but touch operation button position 7, the actual key position 6 that people's finger and conductor are made forms certain electric capacity; Special-purpose capacitance touch IC chip detects the variation of capacitor field intensity between the two through the mode of scanning; Convert the capacitor field intensity variable quantity into digital quantity through AD and send to MCU central processing unit chip, key system just can be judged user's action command, carries out button then and triggers processing and output.Aforementioned actual key position 6 arranged outside shading rings 8 are in order to divide the toggle area scope of different key, thereby avoid misoperation.In fact, the user needn't really touch operation push-button position 7 in use, as long as finger just can trigger button work at a distance from sky according to the inductive spacing zone of this button of guide entering of button sign.Simultaneously; Because actual key position 6, capacitor field intensity detection module 2, control module 3 etc. are installed on the circuit board 5; And operation panel 4 is by material manufacture such as transparent polymethyl methacrylate or ABS, and transparent operation panel does not have any circuit for 4 times, can let the user produce fresh, magical operating experience.

As shown in Figure 3, can cooperate the Digital Logic switch to realize the scanning that the button capacitor field intensity is changed through single capacitance touch IC chip during practical implementation.Connect a Digital Logic switch on the PCB circuit board behind each actual key position; The Digital Logic switch is connected with special-purpose capacitance touch IC chip; Special-purpose capacitance touch IC chip carries out key scan through the open and close of control figure logic switch; And the capacitor field intensity variable quantity of detected respective keys carried out the AD conversion, the data after will change again send to MCU central processing unit chip and carry out corresponding button processing.This scheme is only used a capacitance touch IC chip, saves cost.

As shown in Figure 4; Another implementation method of the scanning circuit that capacitor field intensity changes is that each actual key position directly is connected with a special-purpose capacitance touch IC process chip on the PCB circuit board; Each capacitance touch IC chip is responsible for detecting the capacitor field intensity variation of corresponding button; A plurality of special-purpose capacitance touch IC process chip are connected with the MCU central processing unit respectively, and the MCU central processing unit is realized the scanning to a plurality of IC chips, receive the data that the IC chip sends.Also establish a capacitor field intensity in the special-purpose capacitance touch IC process chip and change threshold values; The capacitor field intensity variable quantity that has only the triggering of user's finger touch operation button is greater than preset field intensity threshold values, and capacitance touch IC chip can be discerned user's action command, and MCU compares a plurality of data that the IC chip sends through certain algorithm; Confirm to have only the maximum button of capacitor field intensity variable quantity to be triggered; Other key is not triggered, and identification valid function and misoperation are handled thereby carry out corresponding key.

Except that the foregoing description, the present invention can also have other execution modes, and all employings are equal to the technical scheme of replacement or equivalent transformation formation, all drop in the protection range of requirement of the present invention.

Claims

1. a projection touch key is characterized in that, comprises button projection module (1), capacitor field intensity detection module (2), control module (3); Said button projection module (1) comprises operation panel (4), circuit board (5); Also comprise at least one actual key position (6) and the operation push-button position (7) corresponding with each actual key position (6); Operation panel (4) is by the non-conducting material manufacturing, and said operation panel (4) and circuit board (5) have angle, and the scope of this angle is 0 °～90 °; Said actual key position (6), capacitor field intensity detection module (2), control module (3) are positioned on the circuit board (5); Operation push-button position (7) is positioned on the operation panel (4), and operation push-button position (7) are in the view field of actual key position (6) on operation panel (4), and the distance of said actual key position (6) and operation push-button position (7) is less than 20 centimetres; Said actual key position (6) links to each other with the input of capacitor field intensity detection module (2); The output of capacitor field intensity detection module (2) links to each other with the input of control module (3); Capacitor field intensity detection module (2) detects the variation of capacitor field intensity between actual key position (6) and operation push-button position (7); And sending variable quantity to control module (3), the button that control module (3) is correlated with is handled.

2. projection touch key as claimed in claim 1 is characterized in that, the conplane outside, said actual key position (6) is provided with shading ring (8).

3. according to claim 1 or claim 2 projection touch key is characterized in that, said capacitor field intensity detection module (2) uses special-purpose capacitance touch IC chip.