CN2775938Y

CN2775938Y - Inductive switch

Info

Publication number: CN2775938Y
Application number: CN 200520057212
Authority: CN
Inventors: 谢勇
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-04-20
Filing date: 2005-04-20
Publication date: 2006-04-26
Anticipated expiration: 2015-04-20

Abstract

The utility model provides an inductive switch, which is composed of an oscillation circuit, an inductive circuit and a logical decision circuit. The inductive circuit is composed of a triode, a bias resistance and a capacitor. One pole of the capacitor of the inductive circuit is a conductor inductive surface which is connected with a base electrode of the triode, and the other pole of the capacitor of the inductive circuit is a human body. The inductive switch uses the conductor inductive surface and the human body as both poles of the inductive capacitor, therefore the human body and a metal plate which is used as the conductor inductive surface are contacted in a non medium mode, or are contacted by an insulator, therefore the inductive switch can be waterproof and anti-electricity-leakage. The inductive switch is convenient and practical, and the inductive switch has longer service life.

Description

A kind of inductive switch

Technical field

The utility model belongs to the electronic device and equipment field, particularly relates to a kind of inductive switch.

Technical background

The switching circuit of electric equipment products such as existing VCD, DVD generally adopts touch-switch, self-lock switch or soft-touch control, its course of work all needs the physics contact, be subjected to the influence of manufacturing process, environment for use, transportation condition and raw material quality useful life, often service time limited, and be difficult to accomplish waterproof and dampproof.

China Patent No. is that 02273008.7 utility model patent discloses a kind of " contactless electronic inductive switch ", comprise detecting element, signaling conversion circuit, signal processing module, main operating circuit, the detected signal of detecting element is by signaling conversion circuit conversion output, the output of signal conversion circuit is connected to the input of signal processing module, the output of signal processing module connects the input of main operating circuit, the detecting element of this utility model is a variable induction electric capacity, a pole plate of this variable induction electric capacity adopts tablet, and another pole plate is other parts of the hand or the health of human body.

This utility model realizes the contactless control to light switch, overcome the deficiency that light switch adopts touch structure, and is comparatively convenient and safe to a certain extent.

By this utility model, its design concept can be transplanted on the switch of electric equipment products such as VCD, DVD, realize non-contact switch control.

Summary of the invention

The purpose of this utility model is to overcome the deficiencies in the prior art, and a kind of non-contact inductive switch is provided.

In order to realize goal of the invention, the technical solution adopted in the utility model is:

A kind of inductive switch, form by oscillating circuit, sensor circuit and logic decision circuit, sensor circuit is made up of triode, biasing resistor and electric capacity, a conductor induction face that very is connected of the electric capacity of described sensor circuit with the base stage of triode, and another is human body very.

Inductance capacitance of the present utility model is made up of human body and conductor induction face, and when the finger of human body or other positions during near conductor induction face, sensor circuit is an exportable pulse signal, with day of reaching electrical equipment control.

Oscillating circuit of the present utility model and logic decision circuit are connected to form by comparator, resistance and electric capacity, and described sensor circuit is connected with oscillating circuit by the emitter of triode, and sensor circuit is connected with the logic decision circuit by the collector electrode of triode.The electric wave that oscillating circuit is exported is input on the emitter of triode, because the base stage bonding conductor sensitive surface of triode, form electric capacity with human body, so electric wave signal is when exporting by the collector electrode of triode, the direct current composition of its output increases along with the increase of electric capacity, the output current of collector electrode inserts the comparator of logic decision circuit, carries out the flat signal of back output height of voltage ratio at the comparator of logic decision circuit, can carry out appliance switch control.

Logic decision circuit of the present utility model also is provided with delay circuit, and delay circuit is by forming with comparator and the resistance that connects and electric capacity, and delay circuit makes only exports a pulse signal when the close conductor induction face of human body, can not export continuously.

Oscillating circuit described in the utility model, sensor circuit and logic decision circuit can be integrated into electric substrate, and conductor induction face can be covered in the electric substrate outer surface, during use, the finger of human body or other positions only need can realize switch control near conductor induction face.

The utility model is by conductor induction face and human body the two poles of the earth as inductance capacitance, so human body with as being no medium between the metallic plate of conductor induction face or contacting across insulator, so can waterproof, anticreep, and convenient and practical, and useful life is longer.

Description of drawings

Fig. 1 is a circuit diagram of the present utility model.

Embodiment

Below in conjunction with accompanying drawing the utility model is described further.

Circuit diagram of the present utility model as shown in Figure 1, square-wave generator, be that oscillating circuit a adopts common oscillating circuit, by comparator C OM1 and resistance R 1, R2, R3, R4, R5, form with capacitor C 1, the output of comparator C OM1 connects the emitter of the triode Q1 of sensor circuit b, triode Q1 adopts the PNP triode, its base stage is connected with metal induction screen 1, the collector electrode of triode Q1 is connected with the electrode input end of the comparator C OM2 of logic decision circuit c by resistance R 8, be connected with biasing resistor R6 and R7 between the emitter and collector of triode Q1 and the base stage respectively, logic decision circuit c is by comparator C OM2, divider resistance R10, R11, and resistance R 9, capacitor C 3 is formed, wherein resistance R 9 and capacitor C 3 are formed delay circuit, resistance R 9 is connected between the resistance R 8 of the electrode input end of comparator C OM2 and sensor circuit b, and capacitor C 3 and resistance R 9 also are connected to the electrode input end of comparator C OM2, and the negative input of comparator C OM2 is connected with divider resistance R10 and R11 in parallel.

The square-wave signal that oscillating circuit a produces enters on the emitter of triode Q1 of sensor circuit b, metal induction screen 1 and the human body 2 of sensor circuit b constitute inductance capacitance, the capacity of electric capacity is inversely proportional to distance, so when human body 2 is responded to screen near metal, the output DC position of sensor circuit b raises, finished the conversion of distance with current potential, the output direct current of sensor circuit b inserts the electrode input end of the comparator C OM2 of logic decision circuit c, because the input current of comparator C OM2 is very little, so anodal input current potential V+ and input current potential V.Approximately equal, the negative input current potential V-=V0*R11/ (R10+R11) of comparator C OM2 is because R10 is not equal to 0, so V-＜V., i.e. V-＜V+, this moment, comparator C OM2 was output as high potential; When human body 2 close metal inductions shielded 1, sensor circuit b output potential raise fast, i.e. V.Current potential raises fast, comparator C OM2 negative pole current potential V-also raises fast, and this moment comparator C OM2 anodal current potential V+ because the effect of delay circuit, it is very slow to rise, so negative pole current potential V-is higher than anodal current potential V+ within a certain period of time, comparator C OM2 exports electronegative potential, anodal current potential V+ slowly rises to and is higher than negative pole current potential V-, comparator C OM2 output this moment high potential, so, when human body 2 close minor metal inductions shielded 1, a switch control was also just finished in electronegative potential pulse of comparator C OM2 output of logic decision circuit c.

Claims

1, a kind of inductive switch, form by oscillating circuit (a), sensor circuit (b) and logic decision circuit (c), sensor circuit (b) is made up of triode, biasing resistor and electric capacity, it is characterized in that a conductor induction face (1) that very is connected with the base stage of triode (Q1) of the electric capacity (C) of described sensor circuit (b), another is human body (2) very.

2, inductive switch according to claim 1 is characterized in that described sensor circuit (b) is connected with oscillating circuit (a) by the emitter of triode (Q1), and sensor circuit (b) is connected with logic decision circuit (c) by the collector electrode of triode.

3, inductive switch according to claim 1 and 2 is characterized in that described logic decision circuit (c) also is provided with delay circuit.

4, inductive switch according to claim 3 is characterized in that described logic decision circuit (c) forms by comparator (COM2), divider resistance (R10, R11) with by the delay circuit that resistance (R9) and electric capacity (C3) are formed.

5, inductive switch according to claim 4 is characterized in that described oscillating circuit (a), sensor circuit (b) and logic decision circuit (c) are integrated into electric substrate.