CN102478672A

CN102478672A - Human body inductive probe

Info

Publication number: CN102478672A
Application number: CN2010105558976A
Authority: CN
Inventors: 张海艇
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-11-22
Filing date: 2010-11-22
Publication date: 2012-05-30

Abstract

The invention provides a human body inductive probe composed of an oscillating circuit, a delay comparison circuit and a logic filter circuit, wherein the delay comparison circuit comprises two NOT gates, a resistor, a capacitor and a metal induction sheet; one of the two NOT gates is used as a reference, and after the other one is delayed by the resistor and the capacitor and capacitors distributed on a human body, the phase of a square wave outputted by the other NOT gate is later than that of a square wave outputted by the oscillating circuit; the logic filter circuit comprises an XOR gate, a resistor and a capacitor; the XOR gate performs logic calculation on the square waves outputted by the two NOT gates, the square wave output by the XOR gate has a different duty ratio, and the duty ratio is determined by the distance from the human body to the metal induction sheet; when the human body is closer to the metal induction sheet, the duty ratio is larger; the square wave with a different duty ratio is filtered to produce a direct current voltage which is proportional to the distance from the human body to the metal induction sheet.

Description

The human body sensing detector

Affiliated technical field

The present invention relates to a kind of detector, especially relate to a kind of human body sensing detector.

Background technology

The useful infrared ray of present known human body sensing detector surveys, and what also have surveys with microwave, but above-mentioned Detection Techniques also exist signal output and the deficiency of human body near the non-linear relation of distance.

Summary of the invention

The purpose of this invention is to provide a kind of signal output and the linear human body sensing detector of the approaching distance of human body, for achieving the above object, the technical scheme that the present invention takes is: by an oscillatory circuit; A time-delay comparator circuit, a logic filtering circuit is formed a human body inductive probe, contains a Sheffer stroke gate in the described oscillatory circuit; A crystal oscillator element; A resistance, two electric capacity, said elements are connected into a square-wave oscillator; It specifically is to connect like this: described crystal oscillator element is connected with input end, the output terminal of Sheffer stroke gate respectively with two ends of resistance; A capacitance series in described two electric capacity is between Sheffer stroke gate input end and ground wire, and another capacitance series is between Sheffer stroke gate output terminal and ground wire, and described oscillatory circuit oscillation frequency is 1MHz.

Contain two not gates in the described time-delay comparator circuit; A resistance that is used to delay time and an electric capacity; A metal inductive sheet that is used to survey human body; A not gate is used for reference in described two not gates, and promptly the phase place of output square wave is consistent in phase place and the oscillatory circuit of its output square wave, and another not gate is exported the phase place of square wave in oscillatory circuit through resistance capacitance and its phase lag of exporting square wave of human body distributed capacitance time-delay back; The degree of phase lag and human body are proportionate relationship near the distance of metal inductive sheet; The described input end that is used for the not gate of reference is connected with the output terminal of oscillatory circuit, and an input end of the XOR gate in its output terminal and the logic filtering circuit is connected, and the input end of described another not gate is connected to a metal inductive sheet; Also be connected simultaneously with an end of described resistance, electric capacity; And the resistance other end is connected on the output terminal of oscillatory circuit, the other end ground wire of electric capacity, and described resistance, electric capacity and metal inductive sheet constitute a delay circuit; Its delay time and human body are proportionate relationship near the distance of metal inductive sheet, and an input end of the XOR gate in the output terminal of described another not gate and the logic filtering circuit is connected.

In described logic filtering circuit, contain an XOR gate; An electric capacity of resistance that is used for filtering; The square wave that described XOR gate is exported two not gates in the time-delay comparator circuit that come carries out logical operation, and the waveform of its output is the square wave of a different duty, and the size of dutycycle depends on that human body is near metal inductive sheet distance; Human body is big more from the nearlyer dutycycle of metal inductive sheet; The square wave of this different duty produces a DC voltage after filtering, and this DC voltage size is proportionate relationship with human body near metal inductive sheet distance, and the described resistance capacitance that is used for filtering is serially connected between the output terminal and ground wire of XOR gate.

Principle of work of the present invention is: human body can produce a distributed capacitance during near the metal inductive sheet; This distributed capacitance makes time of phase lag of square wave of output of a not gate; The square wave of a dutycycle of output produces a needed DC voltage through filtering again after the XOR gate logical operation.

Advantage of the present invention is: the voltage signal of generation and human body are proportionate relationship near metal inductive sheet distance, can be used on some device that this requirement is arranged.

Description of drawings

Fig. 1 is circuit theory diagrams of the present invention

The oscillogram that a point, b point, the c of Fig. 2 when to be human body near metal inductive sheet distance far away ordered

The oscillogram that a point, b point, the c of Fig. 3 when to be human body near metal inductive sheet distance nearer ordered

Embodiment

To narrate specific embodiments with reference to accompanying drawing: form a human body inductive probe by 1, one logic filtering circuit of 3, one time-delay comparator circuits of an oscillatory circuit 14; Contain 6, one resistance 7 of 2, one crystal oscillator elements of a Sheffer stroke gate in the oscillatory circuit 3; Two electric capacity 4,5; Said elements is connected into a square-wave oscillator, and it specifically is to connect like this: crystal oscillator element 6 is connected with input end, the output terminal of Sheffer stroke gate 2 respectively with two ends of resistance 7, and electric capacity 4 is serially connected between Sheffer stroke gate 2 input ends and the ground wire; Electric capacity 5 is serially connected between Sheffer stroke gate 2 output terminals and the ground wire, and the oscillation frequency of described oscillatory circuit 3 is 1MHz.

Contain two not

gates

8,12 in the time-delay comparator circuit 1; Resistance that is used to delay time 9 and 11, one of electric capacity are used to survey the metal inductive sheet 10 of human body, and not gate 8 serves as reference; Be in phase place and the oscillatory circuit of its output square wave 3 export square waves phase place be consistent; And phase lag of not gate 12 its output square wave through resistance 9 electric capacity 11 and human body distributed capacitance time-delay back is exported the phase place of square waves in oscillatory circuit 3, and the degree of phase lag and human body are proportionate relationship near the distance of metal inductive sheet 10, and the input end of not gate 8 is connected with the output terminal of oscillatory circuit 3; An input end of the XOR gate 13 in its output terminal and the logic filtering circuit 14 is connected; The input end of not gate 12 is connected to a metal inductive sheet 10, also be connected with an end of resistance 9, electric capacity 11 simultaneously, and resistance 9 other ends is connected on the output terminal of oscillatory circuit 3; The other end ground wire of electric capacity 11; Described resistance 9, electric capacity 11 and metal inductive sheet 10 constitute a delay circuit, and its delay time and human body are proportionate relationship near the distance of metal inductive sheet 10, and an input end of the XOR gate 13 in the output terminal of not gate 12 and the logic filtering circuit 14 is connected.

In logic filtering circuit 14, contain an XOR gate 13; 15 1 electric capacity 16 of resistance that are used for filtering; The square wave in 8,12 outputs of two not gates that 13 pairs of XOR gates come carries out logical operation, and the waveform of its output is the square wave of a different duty, and the size of dutycycle depends on the distance of human body near metal inductive 10; Human body is big more from metal inductive sheet 10 nearlyer dutycycles; The square wave of this different duty produces a DC voltage after filtering, and this DC voltage size and human body are proportionate relationship near the distance of metal inductive sheet 10, and described resistance 15 electric capacity 16 that are used for filtering are serially connected between the output terminal and ground wire of XOR gate 13.

Claims

1. a human body sensing detector is by an oscillatory circuit 3; A time-delay comparator circuit 1; A logic filtering circuit 14 is formed; It is characterized in that: contain the metal inductive sheet 10 that 8,12, one resistance that are used to delay time 9 of two not gates and 11, one of electric capacity are used to survey human body in the comparator circuit 1 in time-delay.

2. the input end according to claims 1 said not gate 8 is connected with the output terminal of oscillatory circuit 3, and an input end of the XOR gate 13 in its output terminal and the logic filtering circuit 14 is connected.

3. the input end according to the said not gate 12 of claims is connected to a metal inductive sheet 10; Also be connected simultaneously with an end of resistance 9, electric capacity 11; And resistance 9 other ends are connected on the output terminal of oscillatory circuit 3; An input end of the XOR gate 13 in the other end ground wire of electric capacity 11, the output terminal of not gate 12 and logic filtering circuit 14 is connected.