CN2618165Y - Capacitance materials water content measuring equipment - Google Patents
Capacitance materials water content measuring equipment Download PDFInfo
- Publication number
- CN2618165Y CN2618165Y CN 03235285 CN03235285U CN2618165Y CN 2618165 Y CN2618165 Y CN 2618165Y CN 03235285 CN03235285 CN 03235285 CN 03235285 U CN03235285 U CN 03235285U CN 2618165 Y CN2618165 Y CN 2618165Y
- Authority
- CN
- China
- Prior art keywords
- chip microcomputer
- electric capacity
- converter
- output terminal
- buffer amplifier
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Landscapes
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Abstract
The utility model relates to a capacitive material moisture determinator, which is characterized in that: the utility model comprises a fixed capacitor (1), a buffer amplifier (3), a waveform generator (4), an A/D converter (5), a material detector (6), a digital temperature sensor (7), a single chip microcomputer (8), an interface circuit (9), a display instrument or a host computer (10), wherein the fixed capacitor forms a bleeder circuit together with a measuring capacitance; the output end of the waveform generator controlled by the single chip microcomputer switches into the bleeder circuit formed by the fixed capacitor and the measuring capacitance; the output end of the measuring capacitance switches into the input end of the buffer amplifier, of which the output end switches into the analog voltage input end of the A/D converter; the I/O ports of the single chip microcomputer are respectively connected with the digital quantity output end of the A/D converter, the output end of the material detector and the digital quantity output end of the digital temperature sensor; the signals collected by the single chip microcomputer switch in the display unit through the interface circuit.
Description
(1) technical field
The utility model relates to a kind of material moisture analyzer, relates to a kind of condenser type material moisture teller specifically.
(2) background technology
Capacitance method is a kind of method of test material moisture commonly used, and the principle that specific inductive capacity increased when it utilized material water ratio high is measured.Chinese patent 86101309 " Hydroscope for loose substances ", 86200819 " the quick Moisture Meter of condenser type ", 86210321 " measuring cup type micro computer grain moisture analyzers ", 87205091 " pocket solid matter moisture tellers ", 87206844 " pocket grain moisture content fast measuring instrument ", " 88205362.0 high-frequency capacitive moisture teller ", 93212522 " condenser type material moisture tellers ", " 93235926.4 wide temperature low-power consumption grain ' s moisture teller ", " 95201164.6 split type Computerized moisture tacheometer ", " 96206503.X grain on-line moisture determination instrument ", 96246614.X " grain moisture content multiple spot on-line detector " etc. all adopted the method for measuring electric capacity.But the pseudodensity of material also greatly influences the specific inductive capacity of powder and granule shape material during with capacitance method test material moisture, thereby the compaction rate of powder and granule shape material will cause the measuring error of water percentage.This is the not high main cause of condenser type moisture teller precision.Temperature variation changes the relation of material specific inductive capacity and moisture, and temperature also can make the parameter of metering circuit change in addition, causes measuring error.
(3) summary of the invention
The purpose of this utility model provides a kind of when utilizing the capacitance measurement water percentage with regard to being to overcome above-mentioned weak point of the prior art, Measuring Dielectric Constant not only, and measure the dielectric loss and the environment temperature of material, and utilize the funtcional relationship of these three parameters and water percentage to obtain the condenser type material moisture teller of the water percentage of material.
The purpose of this utility model can realize by following measure:
Condenser type material moisture teller of the present utility model comprises and measures fixed condenser, buffer amplifier, waveform generator, A/D converter, material detector, digital temperature sensor, single-chip microcomputer, interface circuit, Displaying Meter or the host computer that capacitance group becomes bleeder circuit; Wherein be added to by fixed condenser and measure the bleeder circuit that electric capacity is formed by the sine wave of the constant amplitude of monolithic processor controlled waveform generator output or square-wave waveform; The voltage waveform of measuring electric capacity output inserts the input end of buffer amplifier through output terminal; The output terminal of buffer amplifier is connected to the analog voltage input of A/D converter; The I/O port of single-chip microcomputer is connected with the digital quantity output terminal of A/D converter, the output terminal of material detector and the digital quantity output terminal of digital temperature sensor respectively; The data-signal of single-chip microcomputer collection inserts display device by interface circuit; Finish mathematics manipulation work by display device, and calculate the water percentage that demonstrates material.
Material detector described in the utility model is made up of rack-mount relatively infrarede emitting diode, infrared receiving tube.Described measurement electric capacity by its that is positioned at material detector below be enclosed with external electrode the annular external electrode insulation shell, form by connecting its center electrode insulation shell that is enclosed with central electrode that supporting member is installed in position, annular external electrode insulation shell axis.
Display device described in the utility model is external Displaying Meter, also is external host computer.
The cross sectional shape of the insulation shell of annular external electrode described in the utility model also can be the shape of other any appropriate, such as octagon structure etc.
The utility model places tested material between annular external electrode insulation shell and the center electrode insulation shell, and instrument has circuit waveform generator, buffer amplifier, A/D converter and the temperature sensor that can measure electric capacity and dielectric loss.
Advantage of the present utility model is when utilizing the capacitance measurement water percentage, but Measuring Dielectric Constant not only but also can be measured the dielectric loss and the environment temperature of material, and utilizes the funtcional relationship of these three parameters and water percentage to obtain the accurate water percentage of material.
(4) description of drawings
Fig. 1 is the schematic block circuit diagram of condenser type material moisture teller of the present utility model.
1 is fixed condenser among the figure, the 2nd, measure electric capacity, the 3rd, buffer amplifier, the 4th, waveform generator, the waveform of the constant amplitude of its output can be that sine wave also can be a square wave, the 5th, A/D converter, the 6th, material detector, the 7th, temperature sensor, the 8th, single-chip microcomputer, the 9th, interface circuit, the 10th, display device (can be Displaying Meter or host computer).
Fig. 2 is the structural drawing of condenser type material moisture teller of the present utility model.
Fig. 3 is that the A of Fig. 2 is to view.
11 is supports of material detector among the figure, the 12nd, the infrarede emitting diode of material detector, the 13rd, infrared receiving tube, the 14th, circuit board, the 15th, the center electrode insulation shell, the 16th, wrap in the central electrode in the insulation shell, the 17th, the external electrode insulation shell, the 18th, wrap in the external electrode in the insulation shell, the 19th, be used to connect Displaying Meter or host computer cable socket.
Fig. 4 is that circuit theory diagrams of the present utility model (adopt the square wave mode to survey electric capacity and dielectric loss
Embodiment).
1 is the mica fixed condenser among the figure, the 2nd, the measurement electric capacity that forms by central electrode and external electrode, the 3rd, with the buffer amplifier of AD820 composition, the 4th, the waveform generator of forming by MAX314 and measure capacitor discharging circuit, 5 are included in the A/D converter in the PIC17F873 single-chip microcomputer, the 6th, the material detector of forming by infrarede emitting diode and infrared receiving tube, the 7th, temperature sensor, adopt the LM77 integrated temperature sensor, the 8th, the PIC16F873 single-chip microcomputer, the 9th, the RS-485 interface circuit that the MAX485 circuit is formed, the 19th, cable socket, the 20th, power unit.
(5) embodiment
The utility model is further described below with reference to embodiment (accompanying drawing), but does not limit the utility model.
As shown in Figure 1, condenser type material moisture teller of the present utility model comprise and measurement electric capacity (2) form fixed condenser (1), buffer amplifier (3), waveform generator (4), A/D converter (5), material detector (6), digital temperature sensor (7), single-chip microcomputer (8), interface circuit (9), Displaying Meter or the host computer (10) of bleeder circuit; Wherein the square-wave waveform by the constant amplitude of waveform generator (4) output of single-chip microcomputer (8) control is added to the bleeder circuit of being made up of fixed condenser (1) and measurement electric capacity (2); Voltage waveform on the measurement electric capacity (2) inserts the input end of buffer amplifier (3) through output terminal; The output terminal of buffer amplifier (3) is connected to the analog voltage input of A/D converter (5); The I/O port of single-chip microcomputer (8) is connected with the digital quantity output terminal of A/D converter (5), the output terminal of material detector (6) and the digital quantity output terminal of digital temperature sensor (7) respectively; The data-signal that single-chip microcomputer (8) is gathered inserts host computer (10) by interface circuit (9); Finish mathematics manipulation work by host computer, and calculate the water percentage that demonstrates material.As Fig. 2, shown in 3, on the support (11) of condenser type material moisture teller, be equipped with relatively by infrarede emitting diode (12), the material detector (6) that infrared receiving tube (13) is formed, be positioned at the material detector below and be provided with the annular external electrode insulation shell (17) that is enclosed with external electrode (18) by it, be installed in the measurement electric capacity (2) that the center electrode insulation shell (15) that is enclosed with central electrode (16) in its of annular external electrode insulation shell (17) position, axis is formed by connecting supporting member, the housing of condenser type material moisture teller is provided with the cable socket (19) that is used to connect host computer, and circuit board (14) is installed in the housing by web member.
The utility model system works principle is as follows: with reference to figure 2, tested material in filling between annular external electrode insulation shell (17) and center electrode insulation shell (15), has formed measurement electric capacity 2; Infrarede emitting diode 12 and infrared receiving tube 13 have been formed material detector 6, certainly, also can adopt the material detector of other form, such as capacitive approach switch.With reference to figure 1, Fig. 4, analog switch MAX314 produces a series of square wave under the control of single-chip microcomputer PIC16F873, and the high level of square wave is 8 volts of voltages of power supply 20 outputs, and low level is 0 volt; Square wave is added to by mica fixed condenser 1 and measures on the electric capacity 2, measure voltage waveform on the electric capacity 2 and be the A/D converter input end of sending into single-chip microcomputer PIC16F873 after 1 buffer amplifier 3 bufferings through gain, the reference voltage that is directly proportional with the square wave amplitude voltage that resistance R 1, R2 dividing potential drop obtain is sent into the A/D converter reference voltage input terminal of single-chip microcomputer PIC16F873, therefore the output of A/D converter is only relevant with the intrinsic standoff ratio of fixed capacity 1 and measurement electric capacity 2, irrelevant with the amplitude of square-wave voltage, reduced source of error.In order to reduce metering circuit to measuring the influence of electric capacity 2, buffer amplifier 3 adopts the rail-to-rail operation amplifier AD820 of low bias current, and without biasing circuit, just the analog switch MAX314 by low current leakage will measure electric capacity 2 short circuit dischanges in low level period of square wave.In the high level period of square wave, square-wave voltage is added to by electric capacity 1 and measures on the electric capacity 2, because the influence of the dielectric loss of electric capacity 2, the voltage of electric capacity 2 is index curve and descends, starting potential is relevant with the electric capacity of measuring electric capacity 2, and the degree that voltage descends and the dielectric loss of electric capacity 2 are that the dielectric loss of tested material is relevant.Single-chip microcomputer PIC16F873 controls A/D converter, voltage before voltage when collection measurement electric capacity 2 waveforms are initial and high level waveform finish, these two data are relevant with electric capacity and the dielectric loss of measuring electric capacity 2, just relevant with the specific inductive capacity and the dielectric loss of material, and these two parameters are relevant with the water percentage of material.If waveform generator output is sinusoidal wave, then can measure amplitude and the phasing degree of measuring sine voltage waveform on the electric capacity 2 by A/D converter, can measure electric capacity and the dielectric loss of measuring electric capacity 2.Digital temperature sensor LM77 passes through I
2The C bus is sent ambient temperature data into single-chip microcomputer.When material shelters from the infrarede emitting diode 12 of material detector 6 and the light path between the infrared receiving tube 13, material detector output high level, the data that expression is gathered are effective; During no material, the material detector output low level, the data that expression is gathered are invalid.Non-online moisture tester can omit material detector.Single-chip microcomputer PIC16F873 is transferred to host computer or special-purpose Displaying Meter 10 by 9 interface circuit MAX485 and cable socket 19 with measurement data.Host computer or special-purpose Displaying Meter utilize the funtcional relationship of electric capacity, dielectric loss and environment temperature and water percentage to obtain the water percentage of material.
The funtcional relationship of electric capacity, dielectric loss and environment temperature and water percentage can be tried to achieve by the way of demarcating.Timing signal, the first different sample of material of some parts of water percentage of preparation and accurately measure the water percentage of sample with standard method, then in test specific inductive capacity and the dielectric loss of each sample under different filling compaction rates under the different environment temperatures, can obtain funtcional relationship between them by the method for mathematics.
Claims (5)
1, a kind of condenser type material moisture teller is characterized in that: it comprises and fixed condenser (1), buffer amplifier (3), waveform generator (4), A/D converter (5), material detector (6), digital temperature sensor (7), single-chip microcomputer (8), interface circuit (9), Displaying Meter or the host computer (10) of measuring electric capacity (2) composition bleeder circuit; Wherein the output terminal by the waveform generator (4) of single-chip microcomputer (8) control inserts the bleeder circuit of being made up of fixed condenser (1) and measurement electric capacity (2); The output terminal of measuring electric capacity (2) inserts the input end of buffer amplifier (3); The output terminal of buffer amplifier (3) is connected to the analog voltage input of A/D converter (5); The I/O port of single-chip microcomputer (8) is connected with the digital quantity output terminal of A/D converter (5), the output terminal of material detector (6) and the digital quantity output terminal of digital temperature sensor (7) respectively; The data-signal that single-chip microcomputer (8) is gathered inserts display device (10) by interface circuit (9).
2, condenser type material moisture teller according to claim 1 is characterized in that: described material detector (6) is made up of the infrarede emitting diode (12), the infrared receiving tube (13) that are installed in relatively on the support (11).
3, condenser type material moisture teller according to claim 1 is characterized in that: described measurement electric capacity (2) by its that is positioned at material detector (6) below be enclosed with external electrode (18) annular external electrode insulation shell (17), form by connecting its center electrode insulation shell (15) that is enclosed with central electrode (16) that supporting member is installed in annular external electrode insulation shell (17) position, axis.
4, condenser type material moisture teller according to claim 1 is characterized in that: described display device (10) is external Displaying Meter.
5, condenser type material moisture teller according to claim 1 is characterized in that: described display device (10) is external host computer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 03235285 CN2618165Y (en) | 2003-01-16 | 2003-01-16 | Capacitance materials water content measuring equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 03235285 CN2618165Y (en) | 2003-01-16 | 2003-01-16 | Capacitance materials water content measuring equipment |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2618165Y true CN2618165Y (en) | 2004-05-26 |
Family
ID=34249570
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 03235285 Expired - Fee Related CN2618165Y (en) | 2003-01-16 | 2003-01-16 | Capacitance materials water content measuring equipment |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2618165Y (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100454010C (en) * | 2007-02-13 | 2009-01-21 | 窦祥增 | Moisture tester for grain and oil crops |
| CN103852487A (en) * | 2012-12-03 | 2014-06-11 | 天津朗辰光电科技有限公司 | Oil-water proportion sensor used for petroleum producing well |
| CN109187669A (en) * | 2018-09-25 | 2019-01-11 | 北京工商大学 | Flour based on dielectric method or the like detecting instrument for moisture content and measuring method |
-
2003
- 2003-01-16 CN CN 03235285 patent/CN2618165Y/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100454010C (en) * | 2007-02-13 | 2009-01-21 | 窦祥增 | Moisture tester for grain and oil crops |
| CN103852487A (en) * | 2012-12-03 | 2014-06-11 | 天津朗辰光电科技有限公司 | Oil-water proportion sensor used for petroleum producing well |
| CN103852487B (en) * | 2012-12-03 | 2016-08-24 | 天津朗辰光电科技有限公司 | A kind of oil-water ratio sensor for Petroleum Production well |
| CN109187669A (en) * | 2018-09-25 | 2019-01-11 | 北京工商大学 | Flour based on dielectric method or the like detecting instrument for moisture content and measuring method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101435788B (en) | On-line oil liquid monitoring sensor based on permittivity measurement and system thereof | |
| CN201583315U (en) | Capacitor array type liquid level sensor probe and liquid sensor using same | |
| CN101907594B (en) | On-line measurement device of crude oil water content of wellhead | |
| CN110231071A (en) | A kind of liquid level emasuring device based on capacitance type sensor | |
| CN104237331A (en) | Oil trace moisture on-line monitoring sensor | |
| CN106645972A (en) | Platform used for detecting resistance value of small resistor | |
| CN201984111U (en) | Circuit for measuring impedance value | |
| CN2502277Y (en) | Intelligent digital multimeter | |
| CN101487811B (en) | Static sounding resistivity probe | |
| CN2618165Y (en) | Capacitance materials water content measuring equipment | |
| CN200959007Y (en) | Water-content determiner | |
| CN213365069U (en) | Multifunctional meteorological data acquisition intelligent analysis device | |
| CN2416506Y (en) | Differential pressure dynamic wind speed measuring apparatus | |
| CN113237526B (en) | Non-contact automatic measuring device and measuring method for volume and mass of liquid | |
| CN201255648Y (en) | Liquid level detecting device | |
| CN201449390U (en) | Crude oil water-bearing detection apparatus | |
| CN204536249U (en) | Based on the oil-water two-phase flow moisture content meter of frequency sweep complex impedance measurement | |
| CN206378535U (en) | A kind of detection platform of small resistor resistance | |
| CN1865915A (en) | Method for detecting viscosity and rigidity of electroluminescent rheid | |
| CN102636236B (en) | Float process shift window interface analyzer based on continuous capacitance measurement | |
| CN104950018A (en) | Mixed gas detecting system | |
| Li et al. | Research on the Detecting Technology of Tiny Capacitance | |
| CN209102801U (en) | A kind of simple digital control multi-functional instrument meter apparatus | |
| CN110672675A (en) | Plant leaf moisture content detector | |
| CN103438911A (en) | LC resonance sensor reading system and method under fixed frequency mode |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |