CN102507651A - Moisture detector for meat - Google Patents

Abstract

The invention discloses a moisture detector for meat, which consists of an alternating current signal generator, two needle-shaped measurement electrodes, a temperature compensation circuit, a high-precision alternating current amplifier and a single chip system, wherein the alternating current signal generator is composed of an IC1 (integrated circuit) (TL062) and a peripheral circuit of the IC1; needle sensors are arranged inside the two needle measurement electrodes; the high-precision alternating current amplifier is composed of an IC2 (TL062) and the peripheral circuit of the IC2 for rectifying and pre-amplifying coupled test current; the single chip system is composed of an IC4 (PIC16C711), and the peripheral circuit of the IC4, and the temperature compensation circuit is composed of a temperature-measurement thermal resistor element Rt, a capacitor C14 and a resistor R37 and is serially connected with a first pin of the single chip PIC16C711.

Description

A kind of meat moisture detector

Technical field

The invention relates to meat standard detection equipment, specifically about meat water content detection instrument.

Background technology

Some lawless person injects large quantity of moisture in order to pursue interests in meat products, cause great hidden for people's health key health, and therefore, the meat moisture detector becomes the indispensable instrument of meat dealer.Main measuring method has oven drying method, optoelectronic induction method, electrical conductivity method, capacitance method etc. at present.But oven drying method length consuming time is unfavorable for fast detecting; The optoelectronic induction method; Like the patent No. is CN 1566929A; The patent of invention of " harmless device for fast detecting of livestock and poultry meat moisture and method " by name discloses a kind of method of measuring the meat water cut easily; It uses the photoelectric measurement principle, calculates moisture through the light intensity signal that detects through the meat scattering, and its shortcoming is the influence that receives the ambient light line strength easily; Traditional electrical conductivity method, capacitance method generally use dc signal as potential electrode or plate signal, and there are polarization phenomena in it, influences measurement result greatly.

Summary of the invention

The present invention has designed a kind of meat moisture detector for addressing the above problem, and it is made up of AC signal generator, needle-like potential electrode, high-precision AC amplifier and SCM system; Described meat moisture detector has adopted the ac electrode measuring method; It has two needle-like potential electrode, and die opening is 3～4 centimetres, and described electrode can produce the ac signal of 120KHZ; This electric signal can record the moisture of meat after special processing, effectively prevented polarization phenomena; It also contains temperature-compensation circuit in addition, has more guaranteed the accuracy of measurement result.

The objective of the invention is to be achieved through following technical scheme.

The present invention is made up of AC signal generator, two needle-like potential electrode, high-precision AC amplifier, temperature-compensation circuit and SCM systems,

Described two needle-like potential electrode; Die opening is 3～4 centimetres; The needle-like sensor is contained in described two its inside of needle-like potential electrode, needle-like sensor signal input termination capacitor C 5, the constant amplitude sinusoid test signal of the 120KHZ that produced by AC signal generator of being used to be coupled; The signal output part of needle-like sensor is connecting resistance R 21, capacitor C 9, the measuring current after the test that is used to be coupled;

Described AC signal generator is made up of IC1 (TL062) and peripheral circuit thereof; The electrode measurement loop current is coupled on precision rectifying and the amplifying circuit through R21, C9; Direct current signal after the amplification exports IC3 (2262) to by 7 pins of IC2 (TL062); After the IC3 amplification and carrying out the current potential translation, through the π shape filtering circuit filtering that C10, R29, C11 form, 18 pins of delivering to single-chip microcomputer again carry out the A/D conversion.

Described SCM system is made up of PIC16C711 single-chip microcomputer and peripheral circuit thereof; Single-chip microcomputer 1,17,18 pins are A/D conversion input end; Respectively the water cut of environment temperature, cell voltage, tested meat is converted into 8 and is digital quantity; R33, R34, R35 and T1 form electrify restoration circuit, the data-signal and the clock signal of the 6th, 7 pins output driving liquid crystal screen, and 8,9 pins are for measuring control button input end.

Described temperature-compensation circuit is by a temperature survey resistance thermometer clement Rt, capacitor C 14, and resistance R 37 is formed, and it is connected with 1 pin of single-chip microcomputer PIC16C711.

Good effect of the present invention is: adopted the ac electrode measuring method, this electrode signal can record the moisture of meat after special processing, effectively prevented polarization phenomena, and it has only two needle-like potential electrode in addition, measures more convenient.

Description of drawings

Fig. 1 signal flow graph of the present invention;

Fig. 2 is circuit voltage change-over circuit figure of the present invention;

Fig. 3 is this AC signal generator circuit diagram;

Fig. 4 is PIC16C711 single-chip microcomputer of the present invention and peripheral circuit diagram thereof;

Embodiment

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

In Fig. 1, visible the present invention is made up of AC signal generator, needle-like potential electrode, high-precision AC amplifier, temperature-compensation circuit and SCM system.

In Fig. 3; Described AC signal generator is made up of IC1 (TL062) and peripheral circuit thereof; The electrode measurement loop current is coupled on precision rectifying and the amplifying circuit through R21, C9, and the direct current signal after the amplification exports IC3 (2262) to by 7 pins of IC2 (TL062), after the IC3 amplification and carrying out the current potential translation; Through the π shape filtering circuit filtering that C10, R29, C11 form, 18 pins of delivering to single-chip microcomputer again carry out the A/D conversion.

In Fig. 4; Described SCM system is made up of PIC16C711 single-chip microcomputer and peripheral circuit thereof; Single-chip microcomputer 1,17,18 pins are A/D conversion input end, respectively the water cut of environment temperature, cell voltage, tested meat are converted into 8 and are digital quantity, and R33, R34, R35 and T1 form electrify restoration circuit; 6th, the data-signal and the clock signal of 7 pins output driving liquid crystal screen, 8,9 pins are for measuring control button input end.

Described temperature-compensation circuit is by a temperature survey resistance thermometer clement Rt, capacitor C 14, and resistance R 37 is formed, and is composed in series in 1 pin of single-chip microcomputer PIC16C711.

During measurement, electrode and temperature survey resistance thermometer clement are inserted in the livestock and poultry meat together, press and begin to measure key PB1; After a while, measure and accomplish, LED light is lighted; Promptly can show the current situation that meat contains moisture value of surveying on the display screen LCM,, press PB1 another position that electrode and temperature survey resistance thermometer clement insert livestock and poultry meat once more; Last time, data measured will be saved in the register of single-chip microcomputer, measured afterwards next time.After measuring N was inferior, the long PB1 that presses continued 3 seconds, can the result who measure be removed maximum, minimum value, gets the mean value of N-2 data, was presented on the LCM, if measured value surpasses the higher limit of national regulation livestock and poultry meat water cut, LED light will not stop to glimmer.When pressing PB2 display screen LCM is resetted, LED light is turn-offed simultaneously.

Claims (1)

1. a meat moisture detector is made up of AC signal generator, two needle-like potential electrode, temperature-compensation circuit, high-precision AC amplifier and SCM systems, it is characterized in that:

Described AC signal generator is made up of IC1 (TL062) and peripheral circuit thereof, is used to produce the constant amplitude sinusoid test signal of 120KHZ;

Described two needle-like potential electrode; Die opening is 3～4 centimetres; The needle-like sensor is contained in described two its inside of needle-like potential electrode, needle-like sensor signal input termination capacitor C 5, the constant amplitude sinusoid test signal of the 120KHZ that produced by AC signal generator of being used to be coupled; The signal output part of needle-like sensor is connecting resistance R 21, capacitor C 9, the measuring current after the test that is used to be coupled;

Described high-precision AC amplifier is made up of IC2 (TL062) and peripheral circuit thereof; Be used for the measuring current after the coupling is carried out rectification and preparatory processing and amplifying; 7 pin of its IC2 are through 5 fens two-way of resistance R: the one tunnel is connected to 7 pin of IC3 through resistance R 24, and one the tunnel is directly connected to 6 pin of IC3; The direct current signal that rectification is amplified back formation exports IC3 to, does further amplification and level shift processing; The potentiometer W1 that the 2 pin places of IC3 connect is used to adjust gain amplifier, and the potentiometer W2 that the 3 pin places of IC3 connect is used to adjust the size of level shift;

Described SCM system is made up of IC4 (PIC16C711) and peripheral circuit thereof; 18 pin of IC4 carry out the A/D conversion; It is connecting the capable filtering circuit of being made up of capacitor C 10, resistance R 29 and capacitor C 11 of π; Be used for the signal of IC3 output is carried out Filtering Processing, to reach higher A/D conversion accuracy;

Described temperature-compensation circuit is by a temperature survey resistance thermometer clement Rt, capacitor C 14, and resistance R 37 is formed, and is composed in series in 1 pin of single-chip microcomputer PIC16C711.

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