CN201163272Y

CN201163272Y - Food salinometer

Info

Publication number: CN201163272Y
Application number: CNU2007201787541U
Authority: CN
Inventors: 叶谋奋; 蔡群英; 张金灵; 童伯宁; 韩臻; 蔡天芳; 王玉凤
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-09-26
Filing date: 2007-09-26
Publication date: 2008-12-10
Anticipated expiration: 2017-09-26

Abstract

The utility model relates to a foodstuff salinometer, which comprises a shell (6), a measuring probe (3), two parallel silver measuring electrodes (1), a temperature sensor (2), a liquid crystal display (4) and a measuring circuit, wherein, the measuring circuit comprises a measuring bridge which consists of an equivalent impedance between the two parallel silver measuring electrodes (1), three standard resistors and a capacitor. The foodstuff salinometer adopts a battery for power supply, can automatically and quickly measure the salinity and the temperature of foodstuff solution and display the salinity value, the temperature value and the humanized character prompt in real time, and has high measurement precision.

Description

The food salinometer

Technical field

The utility model relates to a kind of food salinometer, and especially a kind of salinometer of measuring food solution salt content belongs to the household articles field.

Background technology

Granted publication number discloses a kind of salinometer for the Chinese patent of CN2459657Y, this salinometer is made sensor with the parallel metal sheet of two electrical isolations, be immersed in the solution to be measured, wherein connect the voltage of the positive and negative alternation of fixed amplitude on a slice sheet metal, another sheet sheet metal is exported a DC voltage after receiving signal processing circuit, and this magnitude of voltage is proportional to the salinity of solution.Its weak point is that range needs manual switching, is inconvenient to measure; Adopt positive-negative power supply, volume is big, and power consumption is many; Whole device does not have microcomputer control circuit and display device, and finally is output as magnitude of voltage, rather than the salinity value, needs the user to change function singleness, reading inconvenience separately.

Summary of the invention

In order to overcome the deficiencies in the prior art, the utility model provides a kind of food salinometer.It adopts powered battery, can measure the salinity and the temperature of food solution automatically and fast, shows the text prompt of salinity value, temperature value and the hommization of food solution in real time, is a kind of hand-held household electronic product.

In order to realize the purpose of this utility model, the utility model provides a kind of food salinometer, comprise casing 6, measuring sonde 3, two parallel silver measurement electrodes 1, temperature sensor 2, LCD 4 and metering circuits, it is characterized by: described metering circuit comprises measuring bridge, and described measuring bridge is made of together the equiva lent impedance between described two parallel

silver measurement electrodes

1 and 3 measuring resistances and electric capacity.

Preferably, described metering circuit also comprises single-chip microcomputer, sinusoidal circuit, amplifying circuit, current rectifying and wave filtering circuit, the analog to digital conversion circuit of taking place, wherein, the sinusoidal signal that forcing function generator produces through behind the amplifying circuit as the power supply of measuring bridge, import single-chip microcomputer behind the output quantity process current rectifying and wave filtering circuit of measuring bridge, the analog to digital conversion circuit, the data presentation after single-chip microcomputer is handled input signal and will be handled is in LCD.

Further preferably, described temperature sensor is used for testing environment temperature and food temperature, behind the testing result input single-chip microcomputer salinity value is proofreaied and correct.

The beneficial effects of the utility model are: hand-held this food salinometer, the silver measurement electrode to be inserted in the food solution to be measured, and LCD will show the text prompt of salinity value, temperature value and some hommizations of current food solution in real time.The salimity measurement scope is 0%-5%, and precision reaches 0.1%; Temperature measurement range is 0-100 ℃, and precision reaches 1 ℃.

Description of drawings

Fig. 1 is the structural representation of the utility model food salinometer.

Fig. 2 is the utility model food salinometer metering circuit block diagram.

Fig. 3 is the program flow diagram of the utility model food salinometer.

Fig. 4, Fig. 5 are the metering circuit principle schematic of the utility model food salinometer.

Among the figure:

1, silver measurement electrode; 2, temperature sensor; 3, measuring sonde;

4, LCD; 5, power switch; 6, casing

Embodiment

To describe preferred embodiment of the present invention in detail below, example of the present invention be shown in the accompanying drawing.

Fig. 1 shows the structure of the utility model food salinometer.This food salinometer is made up of casing 6, measuring sonde 3, two parallel silver measurement electrodes 1, temperature sensor 2, LCD 4, power switch 5 and metering circuits.Described measuring sonde 3 is positioned at the place ahead of casing 6, at the head of measuring sonde 3 two parallel silver measurement electrodes 1 and a temperature sensor 2 is installed.Described LCD 4 embeds the side of casing 6, and power switch 5 is installed above casing 6.Described metering circuit is positioned at casing 6 inside.

Fig. 2 is the utility model food salinometer metering circuit block diagram.Shown in the inner branch of Fig. 2 frame of broken lines, described metering circuit comprises parts such as single-chip microcomputer, forcing function generator, amplifying circuit, measuring bridge, current rectifying and wave filtering circuit, analog to digital conversion circuit.Wherein, after the sinusoidal signal that produces of forcing function generator is amplified through amplifying circuit as the power supply of measuring bridge.Described measuring bridge is formed by connecting by the equiva lent impedance between two parallel

silver measurement electrodes

1 and 3 elements such as measuring resistance.Enter single-chip microcomputer behind the output quantity process current rectifying and wave filtering circuit of measuring bridge, the analog to digital conversion circuit.Simultaneously, the digital signal of temperature sensor output also enters single-chip microcomputer.

Further describe the circuit connecting relation of this food salinometer below in conjunction with Fig. 4, Fig. 5.

Fig. 4, Fig. 5 are the metering circuit principle schematic of the utility model food salinometer.As Fig. 4, shown in Figure 5, U4, C4, C5, R4, R5, R7, R8, R11, R12, R13, R14 form high-precision sine wave generating circuit, and it produces the sine wave signal of an amplitude and fixed-frequency.U6, C6, C7, C8, C9, R15, R16 form amplifying circuit, and offset of sinusoidal ripple signal amplifies, and R15 adjusts signal and is amplified to predetermined amplitude.The signal of amplifying circuit output is delivered to measuring bridge.Measuring bridge is made up of J1, C13, R24, R28, R29, and J1 connects two parallel silver measurement electrodes, inserts in the food solution to be measured; Between two parallel silver measurement electrodes, has an equiva lent impedance, it is corresponding with salinity, thereby the sinusoidal signal that measuring bridge output is corresponding with the salinity value, this signal is delivered to the current rectifying and wave filtering circuit of being made up of U5A, U5B, U5C, U5D, R6, R9, R10, R17, R18, R19, R20, R21, R22, R23, R25, R26, R27, R30, R31, R32, R33, D1, D2, C11, C12, C14, obtains the direct current signal corresponding with the salinity value.This direct current signal is delivered to modulus conversion chip U2, convert digital signal to after, deliver to single-chip microcomputer U1 and handle.Simultaneously, the temperature measurement circuit that U3, R2 form measures the digital signal corresponding with temperature value, delivers to single-chip microcomputer U1 and handles.U1, R1, C1, C2, C3, Y1 form Single Chip Microcomputer (SCM) system, handle the signal that receives.After finishing dealing with, Single Chip Microcomputer (SCM) system exports salinity value, temperature value and text prompt information to liquid crystal display displays.Battery BT1 and U7, C15, C16 provide power supply for whole device.In foregoing circuit, U1-U7 selects STC12C5410AD, ADC0832, DS18B20, ICL8038, TL064, LM386, MAX660 chip respectively for use.

The measured temperature value also is used for survey food solution salinity value is carried out temperature correction except that being used for demonstration.Corrected value leaves in the single-chip microcomputer storer with the form of database, and single-chip microcomputer is proofreaied and correct the salinity value in program.

The workflow of this food salinometer is described below in conjunction with Fig. 3.

Fig. 3 is the program flow diagram of the utility model food salinometer.Power switch 5 is opened, and LCD 4 will show greeting, measure after 3 seconds and the demonstration current temperature, show corresponding text prompt afterwards.After 10 seconds, system stability, system begins to measure the temperature and the salinity of food solution.Measuring sonde is put into food solution to be measured, and LCD will show salinity value, temperature value and the text prompt of current food solution in real time.After measurement finishes, probe is shifted out food solution, turn off power switch, clean up measuring sonde and get final product.

Claims

1, a kind of food salinometer, comprise casing (6), measuring sonde (3), two parallel silver measurement electrodes (1), temperature sensor (2), LCD (4) and metering circuits, it is characterized by: described metering circuit comprises measuring bridge, described measuring bridge by the equiva lent impedance between described two parallel silver measurement electrodes (1) and 3 measuring resistances and and electric capacity constitute together.

2, food salinometer according to claim 1, it is characterized by: described metering circuit also comprises single-chip microcomputer, sinusoidal circuit, amplifying circuit, current rectifying and wave filtering circuit, the analog to digital conversion circuit of taking place, wherein, the sinusoidal signal that forcing function generator produces through behind the amplifying circuit as the power supply of measuring bridge, import single-chip microcomputer behind the output quantity process current rectifying and wave filtering circuit of measuring bridge, the analog to digital conversion circuit, the data presentation after single-chip microcomputer is handled input signal and will be handled is in LCD.

3, food salinometer according to claim 2, it is characterized by: described temperature sensor is used for testing environment temperature and food temperature, is used to proofread and correct the salinity value behind the testing result input single-chip microcomputer.

4, food salinometer according to claim 2, it is characterized by: described metering circuit is: U4, C4, C5, R4, R5, R7, R8, R11, R12, R13, R14 form high-precision sine wave generating circuit, and it produces the sine wave signal of an amplitude and fixed-frequency; U6, C6, C7, C8, C9, R15, R16 form amplifying circuit, and offset of sinusoidal ripple signal amplifies, and R15 adjusts signal and is amplified to predetermined amplitude; The signal of amplifying circuit output is delivered to measuring bridge; Measuring bridge is made up of J1, C13, R24, R28, R29, and J1 connects two parallel silver measurement electrodes, inserts in the food solution to be measured; The sinusoidal signal that measuring bridge output is corresponding with the salinity value, this signal is delivered to the current rectifying and wave filtering circuit of being made up of U5A, U5B, U5C, U5D, R6, R9, R10, R17, R18, R19, R20, R21, R22, R23, R25, R26, R27, R30, R31, R32, R33, D1, D2, C11, C12, C14, obtains the direct current signal corresponding with the salinity value; This direct current signal is delivered to modulus conversion chip U2, convert digital signal to after, deliver to single-chip microcomputer U1 and handle; Simultaneously, the temperature measurement circuit that U3, R2 form measures the digital signal corresponding with temperature value, delivers to single-chip microcomputer U1 and handles; U1, R1, C1, C2, C3, Y1 form Single Chip Microcomputer (SCM) system, handle the signal that receives; Exporting salinity value, temperature value and text prompt information to LCD P1 after Single Chip Microcomputer (SCM) system is finished dealing with shows.