CN107228882A - A kind of humidity sensor - Google Patents
A kind of humidity sensor Download PDFInfo
- Publication number
- CN107228882A CN107228882A CN201610169186.2A CN201610169186A CN107228882A CN 107228882 A CN107228882 A CN 107228882A CN 201610169186 A CN201610169186 A CN 201610169186A CN 107228882 A CN107228882 A CN 107228882A
- Authority
- CN
- China
- Prior art keywords
- humidity sensor
- humidity
- signal
- electrode
- detection
- 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.)
- Pending
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
Abstract
This application provides a kind of humidity sensor, including：Driver element, electrode unit, sensing unit；The driver element produces detection driving electric signal and exported；The electrode unit includes in circuit electrically isolated two metal electrodes each other：Driving electrodes and induction electrode；The humidity change of dielectric object can cause the change of impedance between described two metal electrodes between described two metal electrodes；The driving electrodes receive the detection driving electric signal of the driver element output, and the induction electrode produces electric induction by the impedance between the driving electrodes, induced signal is produced therewith and is exported as power detection signal；The sensing unit is coupled with the induction electrode, receives the power detection signal exported by the induction electrode, and the power detection signal is processed as into satisfactory Humidity Detection signal and exported.The humidity sensor that the application is provided has the characteristics of simple in construction, measurement is accurate, easily operated.
Description
Technical field
The application is related to electronic device field, and in particular to a kind of humidity sensor.
Background technology
Humidity sensor is widely used in industry, agricultural production and the daily life of the mankind, raw in agricultural
In production, such as farm, wheatland, the data that people are provided using humidity sensor understand rain fall, soil moisture in the soil
Feelings, in orchard, green house of vegetables, humidity is also an important information, with reference to other data, helps grower
Judge whether to need to irrigate, the Probability of pest and disease damage and whether to take measures；In warehouse, help to supervise
Survey warehouse environment and the situation of stored agricultural product.Especially in recent years, with the rise of Internet of Things, humidity is passed
The effect of sensor can be more and more important.
General humidity sensor has several types：
It is simplest it is a kind of be made up of two metal electrodes and the porous material being connected between two metal electrodes,
Power supply used is direct current.When metal electrode two ends add DC voltage, two interelectrode impedance magnitude reactions
Humidity size.This usual only one of which impedance threshold of humidity sensor, when the impedance measured is less than the threshold
During value, it is taken as wet；Otherwise, it is exactly dry.The advantage of this humidity sensor is simple in construction, cost
It is low；Have the disadvantage：1) precision is low, and the porous material is difficult the shape for simulating blade；2) direct current can make
Metal electrode occurs electrochemical reaction under the wet environment of saliferous and causes galvanic corrosion.
In existing patent, also have and add alternating voltage at metal electrode two ends, utilize two interelectrode impedances
Size detection humidity size.Patent CN204426210U is there is provided " a kind of blade for cuttage and seedling culture is wet
Spend sensor ", the humidity sensor uses alternating voltage, by measure two metal electrodes between impedance come
Humidity is sensed, but the humidity value is simple one threshold value for being used to control heating circuit, when humidity is higher than
Given threshold, heating circuit work；When humidity is less than given threshold, heating circuit is closed.Obviously, it is this
Only " dry ", the sensor of " wet " two states can be only applied to the field not high to humidity data required precision
Close.
Another humidity sensor is capacitance type humidity sensor, and capacitance type humidity sensor is a kind of noncontact
Formula, humidity is measured using capacitive coupling technique, advantage is stable；Have the disadvantage 1) complicated, cost
It is high；2) easily influenceed by other capacitance bodies, the other parts of such as plant, the influence of birds, insect etc..
In addition, there is some humidity sensors to estimate the wet of measured object by sensing the dielectric constant of measured object
Degree, it is similar, patent CN103293189A provide " a kind of plant leaf blade surface moisture sensor and its
Measurement apparatus ", the humidity sensor electrode partial simulation blade shape, the simulation of the humidity sensor
Blade is divided into two parts, and the part on the left side utilizes input, defeated by the copper grid metal electrode of two ring-types
Go out the decay of electrode frequency to sense the humidity on blade face；There is the grid-like of two imitative leaf lines the part on the right
Metal electrode, the metal electrode is bonded at the both sides on blade face, and the blade face of the humidity sensor is to steam spirit
The high cellulose acetate high polymer material of sensitivity, two metal electrodes form electric capacity with middle blade face, by electricity
The change of appearance measures the change of blade humidity, and left and right two parts measured value combines to form final moisture content.
The humidity sensor electrode part can simulate blade shape, can be obtained using radio frequency reflection and capacitance principle
Quantitative humidity value, but it is complicated, not only need two groups of humidity measuring instruments, in addition it is also necessary to which one with micro-
The processing platform cooperation of processor, and limited by structure, humidity sensor and the processing platform distance
Short, the spatial dimension of moisture measurement is limited, in addition, flexible blade material also easily causes gold at work
Belong to the damage of electrode.
The content of the invention
The application provides a kind of humidity sensor, overcomes currently with the impedance of measured object to detect humidity
Humidity sensor only " dry ", " wet " two states, it is impossible to which accurate measurement humidity value obtains defect, avoids again
Condenser type, permittivity are complicated, and cost is high, and the deficiency easily influenceed by other non-measured objects.
The humidity sensor that the application is provided, including：
Produce detection driving electric signal and the driver element exported；
Electrode unit, the electrode unit includes in circuit electrically isolated two metal electrodes each other：Driving
Electrode and induction electrode；The driving electrodes and the induction electrode are attached on substrate with the shape set；
The humidity change of dielectric object can cause the change of impedance between described two metal electrodes between described two metal electrodes
Change；The driving electrodes receive the detection driving electric signal of the driver element output, and the induction electrode leads to
The impedance crossed between the driving electrodes produces electric induction, and induced signal is produced therewith and is used as power detection signal
Output；
Sensing unit, the sensing unit is coupled with the induction electrode, and reception is exported by the induction electrode
Power detection signal, and the power detection signal is processed as satisfactory Humidity Detection signal and exported.
Optionally, the driver element includes alternating current generative circuit；The detection driving electric signal is the friendship
Stream is electrically generated the alternating current of circuit output.
Optionally, the alternating current generative circuit uses unstable state multi-resonant oscillating circuit form.
Optionally, the substrate is to adopt the thin plate being made from an insulative material, including：
The blade shape similar to the plant leaf blade of measuring moisture to be checked, is used as the electrode of the electrode unit carrier
Area；
Energized as the driver element, the sensing unit circuit carrier, including for the humidity sensor
Input, grounding ports, the circuit region of the output port of the sensing unit；
The electrode district is connected with the circuit region.
Optionally, the induction electrode is parallel to each other with driving electrodes formation and width identical determines number
On the strip branch of amount, the substrate surface for being distributed on the electrode of substrate area；The strip of Different electrodes point
Branch is alternately distributed and spacing is consistent；It is conducting between the strip branch of same electrode.
Optionally, the branch trends of the induction electrode and the driving electrodes with measuring moisture to be checked
The vein trend of plant leaf blade is consistent.
Optionally, the induction electrode is etched on the substrate with the driving electrodes.
Optionally, the induction electrode and the driving electrodes surface gold-plating.
Optionally, the sensing unit includes filter circuit；The sensing unit is coupled with the induction electrode,
Specifically described filter circuit is coupled with the induction electrode, the institute for the form of communication that induction electrode is exported
Power detection signal rectification is stated for DC signal.
Optionally, the sensing unit includes integrated operational amplifier circuit；The integrated operational amplifier circuit with
The filter circuit coupling, receives the DC signal of the filter circuit output, by the DC signal
Exported after shaping, amplification.
Optionally, the Humidity Detection signal of the humidity sensor output is d. c. voltage signal；The direct current
Voltage signal size is linear corresponding with the humidity value of measured medium thing；Two extreme values of the d. c. voltage signal
Adiabatic drying and completely moistening are represented respectively.
Optionally, the d. c. voltage signal is 0-2V DC voltage：0V represents adiabatic drying, 2V generations
Table is moistened completely.
Optionally, the operating voltage of the humidity sensor is 2.6-10V direct current.
Optionally, the input port of the humidity sensor is between the driver element input and earth terminal；
The output port of the humidity sensor is between the output and ground of the sensing unit.
Optionally, there is protective case outside the circuit region of the humidity sensor.
Present invention also provides a kind of humidity measuring instrument, including：
Humidity sensor, i.e., humidity sensor described above；
Mounting frame for sensor, the mounting bracket is used to the humidity sensor being arranged in test environment,
Ensure that installation site, the angle of the humidity sensor are similar to the plant leaf blade in the test environment；
Sensor detection node, the sensor test node provides electric energy for the humidity sensor, and connects
The Humidity Detection signal that the humidity sensor is passed over is received, is exported after treatment；
Cable, the cable is to connect the humidity sensor and the sensor detection node.
Optionally, the sensor detection node includes：
Analog-to-digital conversion module, the Humidity Detection that the analog-to-digital conversion module passes over the humidity sensor
Signal is converted into data signal；
Central processing module, the central processing module is according to predetermined test program, to the humidity sensor
Device sends detection and required, and the humidity data obtained in detection cycle is handled；
Power module, the power module is that the sensor test node and the humidity sensor are energized；
Wireless communication module, the humidity data that the wireless communication module will be obtained from the central processing module
Distance host is sent to, and receives the instruction of the distance host.
Compared with prior art, the application has advantages below:
The humidity sensor that the application is provided, with driver element, electrode unit and sensing unit, wherein electricity
Pole unit is provided with driving electrodes and induction electrode, and impedance between the two can be with Jie between the two
Matter thing humidity changes and changed.So, when driving electrodes receive the detection drive signal of driver element offer
Afterwards, the induction electrode output power detection signal can be due to different and different, the sensing of dielectric object humidity
Unit receives the Humidity Detection signal exported after the power detection signal of above-mentioned induction electrode output and processing just can be with
Reflect that the humidity of environment to be detected is related.Using such a technical scheme, circuit simple in construction can be used real
Now humidity value is more accurately measured.
Because in the above-mentioned technical solutions, driver element can be designed as exporting different detections drives as needed
Dynamic signal, this just provides possibility to meet the particular/special requirement of different detection environment.For example, the application's
In preferred embodiment, the driver element can be designed as exporting the detection drive signal of form of communication, lead to
The selection using higher alternating current voltage frequency is crossed, it is possible to prevente effectively from shadow of the electrochemical corrosion to metal electrode
Ring, and the detection cycle of the humidity sensor can also be made by higher alternating current voltage frequency
Shorten, save electric energy.
In the preferred embodiment of the application, the metal electrode of the humidity sensor be it is equally distributed,
It is also linear for ensure that output voltage；It is easy to demarcate the humidity sensor.
In the preferred embodiment of the application, a kind of structure of the humidity sensor has and hygrometric to be checked
The vein trend of the similar shape of the plant leaf blade of degree, the shape of metallic grid and blade is consistent, described wet
Spend sensor correctly install in the case of, can very well simulation real blade surface water landing, evaporate,
And thermal capacitance characteristic is also close to the plant leaf blade of a piece of normal size.
Brief description of the drawings
The function unit figure for the humidity sensor that Fig. 1 the application first embodiment is provided；
The structure chart for the leaf wetness sensors that Fig. 2 the application second embodiment is provided；
The outline drawing for the leaf wetness sensors that Fig. 3 the application second embodiment is provided；
The module composition figure for the humidity measuring instrument that Fig. 4 the application 3rd embodiment is provided.
Embodiment
Many details are elaborated in the following description to fully understand the present invention.But it is of the invention
Can be implemented with being much different from other manner described here, those skilled in the art can without prejudice to
Similar popularization is done in the case of intension of the present invention, therefore the present invention is not limited to the specific embodiments disclosed below.
The application first embodiment provides a kind of humidity sensor, and Fig. 1 shows the humidity sensor
Function unit figure.
As shown in figure 1, the humidity sensor includes driver element 1, electrode unit 2 and sensing unit 3.
The generation detection that act as of the driver element 1 drives electric signal.The driver element 1 includes one
Operational amplifier U1B in multi-resonant oscillating circuit, the multi-resonant oscillating circuit is operated in voltage comparator state,
Positive feedback network is by R2, and R3 is by the input in the same direction after output voltage V1 partial pressures with U1B, i.e. "+"
End be connected, as reference voltage V+；The backward voltage V- of reverse input end "-" takes free capacitance C6 and electricity
With hindering electric capacity C6 and power supply described in the oscillating circuit of the R4 compositions voltage between GND.The reverse electricity
Pressure V- and the reference voltage V+compared, determine that the output voltage V1 exports high level or low level.
Because the electric capacity C6 is constantly charged and discharged in positive and negative both direction, the backward voltage V- is set constantly to be more than
With less than the reference voltage V+, make output voltage V1 punctuated turning overs between low, high level, thus
To the ac signal of certain frequency, the frequency and the resistance and the capacitance of selected electric capacity of selected resistance
It is related.The output voltage V1 becomes detection driving voltage V2 and is output to institute after the filtering by electric capacity C2
State electrode unit 2.Detection driving voltage V2 is the detection driving electric signal.
In this example, it is assumed that the driver element 1 is by reasonably selecting the resistance and electricity of related resistors
The capacitance of appearance, generates frequency and drives electric signal as the detection for 5KHz ac signal.5KHz
The cycle of alternating current is 0.2ms, and this allows the moisture measurement cycle to foreshorten to 1ms or shorter, and measures week
The shortening of phase means low power consumption；Meanwhile, the detection driving electric signal of upper frequency can also effectively be prevented
The only electrochemical corrosion of each electrode of the electrode unit.
The electrode unit 2 includes metal electrode：Driving electrodes 201, induction electrode 202, and it is used as institute
State the substrate 24 of the carrier of driving electrodes 201 and induction electrode 202.
The driving electrodes 201, the formation of induction electrode 202 are parallel to each other and width identical, quantification
Strip branch；It is distributed on the substrate surface；The institute of the driving electrodes 201, induction electrode 202
State that strip branch is alternately distributed and spacing is consistent；It is conducting between the strip branch of same electrode.
It is uniform because the strip branch spacing of the metal electrode is consistent, and on the substrate,
So on the substrate surface water number be directly proportional to the impedance between the metal electrode, metal electricity
The impedance of interpolar is directly proportional to the output voltage of the humidity sensor, so, the output voltage with it is described
The humidity of substrate surface is exactly linear corresponding relation.
The driver element 1 is connected with the driving electrodes 201 of the electrode unit 2, the electrode list
The induction electrode 202 of member 2 is connected with sensing unit 3；The detection driving voltage V2 is by described
It is defeated from the induction electrode 202 between driving electrodes 201 and the induction electrode 202 after the decay of impedance
Go out alternating voltage V3 to the sensing unit 3.
The sensing unit 3 includes rectification circuit, filter circuit and operational amplifier U1A.
The sensing unit 3 receives the alternating voltage V3 that the induction electrode 202 is passed over, the exchange
Voltage V3 is described first by the rectification circuit being made up of electric capacity C4, resistance R7 and diode D1
One-way conduction effect and the discharge principle of the electric capacity C4 of the rectification circuit using the diode D1, by institute
State ac voltage signal V3 and become d. c. voltage signal V4.
The d. c. voltage signal V4 by the electric capacity C4 flash-over characteristics due to being influenceed, it is impossible to is completely secured
D. c. voltage signal it is uniform and stable；There are the filter circuit, the filtering in the rear end of the rectification circuit
Circuit includes electric capacity C3 and resistance R6, the filter circuit by the charge and discharge characteristic of the electric capacity C3,
The waveform of the d. c. voltage signal V4 is further smoothed, galvanic current pressure signal V5 is obtained.
The d. c. voltage signal V5 accesses the port 3 of the operational amplifier U1A, and negative feedback network will be defeated
Go out the reverse input end that voltage is loaded into the operational amplifier U1A after resistance R8, resistance R5 partial pressures,
That is port 2；The resistance value that the resistance R8 and resistance R5 chooses determines the operational amplifier U1A
Multiplication factor.
The power end of the operational amplifier U1A is grounded and external direct current power supply VCC connections respectively；It is described
It is provided with filter capacitor to filter external direct current power supply between GND external direct current power supply VCC and power supply
VCC alternating component.
The d. c. voltage signal V5 is used as detection output voltage V6 after amplifying through the operational amplifier U1A
Output, after demarcation, the humidity value line of the measured object between detection output voltage V6 and the metal electrode
Property correspondence, by selecting suitable electrical parameter, the detection output voltage V6 can be adjusted in maximum
Between value 2V and minimum value 0V, wherein, maximum 2V represents complete moistening；Minimum value is that 0V is represented absolutely
To drying.
The humidity sensor that the present embodiment is provided detects electric signal in driver element generation exchange, defeated
It is d. c. voltage signal to go out electric signal, and circuit only includes basic electronic component, without processor, structure
Simply；The humidity value of the output electric signal and measured object is into linear dependence, and demarcation is simple；Internal high frequency is handed over
The application of stream detection electric signal can not only mitigate the galvanic corrosion of the metal electrode, moreover it is possible to shorten detection cycle,
Save electric energy.
Present invention also provides second of embodiment：A kind of leaf wetness sensors.
The leaf wetness sensors are one kind of humidity sensor, for detecting plant leaf blade surface moisture,
It is the critical component of information gathering in automation agricultural；On the other hand, the size of plant surface humidity, continue
Time is the significant data required for the monitoring prevention of plant pest.
In order to correctly measure blade surface humidity, leaf wetness sensors should be met：
1st, the physical characteristic of humidity sensor should be similar as far as possible with the characteristic of real blade, and the humidity is passed
Sensor should simulate shape, thermal characteristics, thickness and the surface emissivity characteristic of real blade, so, described wet
The moisture spent on sensor is just consistent with real blade.
2nd, precise and stable measuring method must be used, this method should be anti-interference, reproducible, not
Humidity Detection value will be easy to demarcation under same obstruction conditions.
3rd, the measuring method used should be able to prevent the galvanic corrosion of electrode, extend the life-span of the humidity sensor.
Further, the leaf wetness sensors should also meet the market demand：
1st, low power consumption, low-work voltage, can in very wide voltage range steady operation, so, institute
Stating humidity sensor can just match with various data collecting systems, including be sensed by battery-driven wireless type
Device detection node.
2nd, the corrosion of chemical substance in galvanic corrosion, anti-rainwater, agricultural chemicals and birds droppings can be resisted.
3rd, low production cost.
Fig. 2 shows the structure chart for the leaf wetness sensors that second embodiment is provided.The leaf wetness
Sensor can be considered as an application of the humidity sensor that above-mentioned first embodiment is provided, wet to the blade face
In the introduction for spending sensor, the humidity sensor identical element of every and first embodiment, using same
The label of sample.
As shown in Fig. 2 the leaf wetness sensors include：Driver element 1, electrode unit 2, sensing are single
Member 3, substrate 24, input/output interface 25.
The driver element 1 produces detection driving electric signal.The specific implementation of the driver element, please join
The driver element 1 seen in above-mentioned first embodiment.
The electrode unit 2 includes metal electrode：Driving electrodes 201, induction electrode 202.
The driving electrodes 201, the formation of induction electrode 202 are parallel to each other and width identical, quantification
Strip branch；On the substrate surface for being distributed on the electrode district；The driving electrodes 201, induction electrode
The 202 strip branch is alternately distributed and spacing is consistent；It is to lead between the strip branch of same electrode
Logical.
It is uniform because the strip branch spacing of the metal electrode is consistent, and on the substrate 24,
So on the substrate surface water number be directly proportional to the impedance between the metal electrode, metal electricity
The impedance of interpolar is directly proportional to the output voltage of the humidity sensor, so, the output voltage with it is described
Water is exactly linear corresponding relation on substrate surface.
The driver element 1 is connected with the driving electrodes 201, the induction electrode 202 and sensing unit
03 connection；The detection driving voltage produced by the driver element 01 is passing through the driving electrodes 201
Become ac voltage signal after the decay of impedance between the induction electrode 202 and be output to the sensing unit
3, become d. c. voltage signal output, the direct current after the filtering, rectification, amplification of the sensing unit 3
It is exactly the Humidity Detection signal to press signal.
The leaf wetness sensors provided for the present embodiment, the substrate 24 is to use electrically insulating material system
Into thin plate, material is FR-4 glass-epoxy force fit plates.
The substrate 24 includes two regions：Electrode district, the electrode district makes the shape of blade, the drive
Moving electrode 201 and induction electrode 202 are distributed in electrode district；Circuit region, the circuit region is that the driving is single
The carrier of member 1 and sensing unit 3.
The material of the metal electrode is copper, the metal electrode, the driver element and the sensing unit
Circuit pack be all by with make printed circuit board (PCB) identical processing technology be etched on the substrate 24.
The driving electrodes 201, induction electrode 202 outer surface it is gold-plated, gold can effectively prevent the metal
Electrode is corroded by rainwater, birds droppings, agricultural chemicals energy chemical substance, extends the use longevity of the humidity sensor
Life.
The humidity sensor also includes input, output port 25, for accessing supply voltage and output institute
State Humidity Detection signal.
Fig. 3 shows the outline drawing of the leaf wetness sensors, as shown in figure 3, the humidity sensor
Also include protective case 26, waterproof gasket cement is scribbled in the protective case 26 and the interface of the substrate 24, rise
To the effect for the driver element 1 and the sensing unit 3 protected on the substrate 24.
Present invention also provides the third embodiment：A kind of humidity measuring instrument, Fig. 4 is that 3rd embodiment is carried
The module composition figure of the humidity measuring instrument of confession.
As shown in figure 4, the humidity measuring instrument includes：Humidity sensor S1, mounting frame for sensor S2,
Sensor detection node S3, cable S4.
The humidity sensor S1 is exactly the humidity sensor that the present embodiment is provided.
The mounting frame for sensor S2 is used to the humidity sensor S1 being arranged in test environment, protects
Installation site, the angle for demonstrate,proving the humidity sensor S1 are similar to the plant leaf blade in the test environment.
The sensor detection node S3 provides electric energy for the humidity sensor, and receives the humidity sensor
The Humidity Detection signal that device is passed over, is exported after treatment；The sensor detection node S3 includes：
Analog-to-digital conversion module S301, the humidity that the analog-to-digital conversion module passes over the humidity sensor
Detection signal is converted into data signal；
Central processing module S302, the central processing module is according to predetermined test program, to the humidity
Sensor sends detection and required, and the humidity data obtained in detection cycle is handled；
Wireless communication module S303, the wireless communication module S303 will be from the center processing S302 modules
The humidity data of acquisition is sent to distance host, and receives the instruction of the distance host；
Power module S304, the power module is the sensor detection node S303 and the humidity sensor
Device S1 is energized.
The sensor detection node S3 can manually set detection cycle and humidity data transmission cycle, or logical
Cross long-range host setting.
The cable S4 is described to connect the humidity sensor S1 and the sensor detection node S3
Cable S3 includes three kinds of cables：
Signal wire, the signal wire connects the output port and the analog-to-digital conversion mould of the humidity sensor S1
Block S301 input port；
Power line, the power line connects the power input interface and the power supply mould of the humidity sensor S1
Block S304 output interface；
Ground wire, the ground wire connects the grounding ports of the humidity sensor S1 and the sensor is detected
Node S3 grounding ports, it is ensured that the humidity sensor S1 reliable grounds.
The course of work of the humidity detector can be described as follows：
When the central processing module S302 starts detection according to the detection cycle of setting, first to the power supply
Module S304 sends power supply instruction, and the power module S304 connects the power supply of the humidity sensor,
When power supply is loaded into the driver element 1 of the humidity sensor, the driver element 1 produces exchange
Detection drive signal is loaded into the driving electrodes 201, and the sensing unit 3, which is received, passes through the driving electrodes
The power detection signal between 201 and the induction electrode 202 after dielectric object resistive degeneration, and its is whole
After stream, filtering, amplification, as the Humidity Detection signal output, the analog-to-digital conversion module S301 passes through
The signal wire receives the Humidity Detection signal, is translated into after data signal and is transmitted to the center processing
Module S302, the central processing module S302 store the data signal.Detection cycle terminates, it is described in
Centre processing module S302 sends cut-offing instruction, the power module S304 cut-outs to the power module S304
The power supply of the humidity sensor.
Although the present invention is disclosed as above with preferred embodiment, it is not for limiting the present invention, Ren Heben
Art personnel without departing from the spirit and scope of the present invention, can make possible variation and modification,
Therefore the scope that protection scope of the present invention should be defined by the claims in the present invention is defined.
Claims (17)
1. a kind of humidity sensor, it is characterised in that the humidity sensor includes：
Produce detection driving electric signal and the driver element exported；
Electrode unit, the electrode unit includes in circuit electrically isolated two metal electrodes each other：Driving
Electrode and induction electrode；The driving electrodes and the induction electrode are attached on substrate with the shape set；
The humidity change of dielectric object can cause the change of impedance between described two metal electrodes between described two metal electrodes
Change；The driving electrodes receive the detection driving electric signal of the driver element output, and the induction electrode leads to
The impedance crossed between the driving electrodes produces electric induction, and induced signal is produced therewith and is used as power detection signal
Output；
Sensing unit, the sensing unit is coupled with the induction electrode, and reception is exported by the induction electrode
Power detection signal, and the power detection signal is processed as satisfactory Humidity Detection signal and exported.
2. humidity sensor according to claim 1, it is characterised in that the driver element includes handing over
Stream is electrically generated circuit；The detection driving electric signal is the alternating current that the alternating current generative circuit is exported.
3. humidity sensor according to claim 2, it is characterised in that the alternating current generative circuit
Using unstable state multi-resonant oscillating circuit form.
4. humidity sensor according to claim 1, it is characterised in that the substrate is using insulation
The thin plate that material is made, including：
The blade shape similar to the plant leaf blade of measuring moisture to be checked, is used as the electrode of the electrode unit carrier
Area；
Energized as the driver element, the sensing unit circuit carrier, including for the humidity sensor
Input, grounding ports, the circuit region of the output port of the sensing unit；
The electrode district is connected with the circuit region.
5. humidity sensor according to claim 4, it is characterised in that the induction electrode with it is described
Driving electrodes formation be parallel to each other and width identical quantification strip branch, be distributed on substrate electricity
On the substrate surface of polar region；The strip branch of Different electrodes is alternately distributed and spacing is consistent；It is same
It is conducting between the strip branch of electrode.
6. humidity sensor according to claim 5, it is characterised in that the induction electrode with it is described
Driving electrodes the branch trend with institute the plant leaf blade of measuring moisture to be checked vein trend unanimously.
7. humidity sensor according to claim 1, it is characterised in that the induction electrode with it is described
Driving electrodes are etched on the substrate.
8. humidity sensor according to claim 1, it is characterised in that the induction electrode with it is described
Driving electrodes surface gold-plating.
9. humidity sensor according to claim 2, it is characterised in that the sensing unit includes filter
Wave circuit；The sensing unit is coupled with the induction electrode, specifically described filter circuit and the sensing
Electrode is coupled, and the power detection signal rectification for the form of communication that induction electrode is exported is DC signal.
10. humidity sensor according to claim 9, it is characterised in that the sensing unit includes
Integrated operational amplifier circuit；The integrated operational amplifier circuit is coupled with the filter circuit, receives the filter
The DC signal of wave circuit output, will be exported after the DC signal shaping, amplification.
11. humidity sensor according to claim 10, it is characterised in that the humidity sensor is defeated
The Humidity Detection signal gone out is d. c. voltage signal；The d. c. voltage signal size is wet with measured medium thing
The linear correspondence of angle value；Two extreme values of the d. c. voltage signal represent adiabatic drying and completely moistening respectively.
12. humidity sensor according to claim 11, it is characterised in that the d. c. voltage signal
It is 0-2V DC voltage：0V represents adiabatic drying, and 2V represents complete moistening.
13. humidity sensor according to claim 1, it is characterised in that the humidity sensor
Operating voltage is 2.6-10V direct current.
14. humidity sensor according to claim 1, it is characterised in that the humidity sensor
Input port is between the driver element input and earth terminal；The output port of the humidity sensor exists
Between the output and ground of the sensing unit.
15. humidity sensor according to claim 4, it is characterised in that the humidity sensor
There is protective case outside the circuit region.
16. a kind of humidity measuring instrument, it is characterised in that including：
Humidity sensor, using the humidity sensor described in claim 1- claim 15 any one；
Mounting frame for sensor, the mounting bracket is used to the humidity sensor being arranged in test environment,
Ensure that installation site, the angle of the humidity sensor are similar to the plant leaf blade in the test environment；
Sensor detection node, the sensor test node provides electric energy for the humidity sensor, and connects
The Humidity Detection signal that the humidity sensor is passed over is received, is exported after treatment；
Cable, the cable is to connect the humidity sensor and the sensor detection node.
17. humidity measuring instrument according to claim 16, it is characterised in that the sensor detection
Node includes：
Analog-to-digital conversion module, the Humidity Detection that the analog-to-digital conversion module passes over the humidity sensor
Signal is converted into data signal；
Central processing module, the central processing module is according to predetermined test program, to the humidity sensor
Device sends detection and required, and the humidity data obtained in detection cycle is handled；
Power module, the power module is that the sensor test node and the humidity sensor are energized；
Wireless communication module, the humidity data that the wireless communication module will be obtained from the central processing module
Distance host is sent to, and receives the instruction of the distance host.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610169186.2A CN107228882A (en) | 2016-03-23 | 2016-03-23 | A kind of humidity sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610169186.2A CN107228882A (en) | 2016-03-23 | 2016-03-23 | A kind of humidity sensor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN107228882A true CN107228882A (en) | 2017-10-03 |
Family
ID=59932891
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610169186.2A Pending CN107228882A (en) | 2016-03-23 | 2016-03-23 | A kind of humidity sensor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107228882A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108742333A (en) * | 2018-05-30 | 2018-11-06 | 上海与德通讯技术有限公司 | A kind of cleaning method and robot |
| CN109540220A (en) * | 2018-12-28 | 2019-03-29 | 河南汉威智慧安全科技有限公司 | Water condensation detection circuit and explosion-proof wiring box internal environment detector |
| CN110200636A (en) * | 2019-07-05 | 2019-09-06 | 北京中硕众联智能电子科技有限公司 | Plantar pressure sensor and its detection pressure, humidity and the method for collecting energy |
| CN117705199A (en) * | 2024-02-05 | 2024-03-15 | 四川芯音科技有限公司 | High-performance MEMS temperature and humidity sensor |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1167430A (en) * | 1995-09-13 | 1997-12-10 | 菲利浦电子有限公司 | Hair-care appliance with hair-moistness measurement by measuring the resistance of the hair, and circuit for converting the resistance value of aresistor into a measurement signal |
| CN203025135U (en) * | 2012-12-04 | 2013-06-26 | 广东美的微波电器制造有限公司 | Humidity detection device |
| CN103293189A (en) * | 2013-05-24 | 2013-09-11 | 北京农业智能装备技术研究中心 | Plant leaf surface humidity sensor and plant leaf surface humidity measurement device |
| CN203519533U (en) * | 2013-08-24 | 2014-04-02 | 西北农林科技大学 | Impedance-method straw moisture detection device |
| CN104865297A (en) * | 2014-02-20 | 2015-08-26 | 钰太芯微电子科技（上海）有限公司 | Humidity detecting circuit and mobile terminal |
| CN205506739U (en) * | 2016-03-23 | 2016-08-24 | 北京科百宏业科技有限公司 | Humidity sensor |
-
2016
- 2016-03-23 CN CN201610169186.2A patent/CN107228882A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1167430A (en) * | 1995-09-13 | 1997-12-10 | 菲利浦电子有限公司 | Hair-care appliance with hair-moistness measurement by measuring the resistance of the hair, and circuit for converting the resistance value of aresistor into a measurement signal |
| CN203025135U (en) * | 2012-12-04 | 2013-06-26 | 广东美的微波电器制造有限公司 | Humidity detection device |
| CN103293189A (en) * | 2013-05-24 | 2013-09-11 | 北京农业智能装备技术研究中心 | Plant leaf surface humidity sensor and plant leaf surface humidity measurement device |
| CN203519533U (en) * | 2013-08-24 | 2014-04-02 | 西北农林科技大学 | Impedance-method straw moisture detection device |
| CN104865297A (en) * | 2014-02-20 | 2015-08-26 | 钰太芯微电子科技（上海）有限公司 | Humidity detecting circuit and mobile terminal |
| CN205506739U (en) * | 2016-03-23 | 2016-08-24 | 北京科百宏业科技有限公司 | Humidity sensor |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108742333A (en) * | 2018-05-30 | 2018-11-06 | 上海与德通讯技术有限公司 | A kind of cleaning method and robot |
| CN109540220A (en) * | 2018-12-28 | 2019-03-29 | 河南汉威智慧安全科技有限公司 | Water condensation detection circuit and explosion-proof wiring box internal environment detector |
| CN109540220B (en) * | 2018-12-28 | 2023-11-17 | 河南汉威智慧安全科技有限公司 | Water condensation detection circuit and explosion-proof junction box internal environment detector |
| CN110200636A (en) * | 2019-07-05 | 2019-09-06 | 北京中硕众联智能电子科技有限公司 | Plantar pressure sensor and its detection pressure, humidity and the method for collecting energy |
| CN110200636B (en) * | 2019-07-05 | 2024-02-02 | 北京中硕众联智能电子科技有限公司 | Plantar pressure sensor and method for detecting pressure, humidity and collecting energy by plantar pressure sensor |
| CN117705199A (en) * | 2024-02-05 | 2024-03-15 | 四川芯音科技有限公司 | High-performance MEMS temperature and humidity sensor |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107228882A (en) | A kind of humidity sensor | |
| Boada et al. | Battery-less soil moisture measurement system based on a NFC device with energy harvesting capability | |
| CN101398405B (en) | Water electric conductivity intelligent sensor | |
| CN204613137U (en) | Air-anion concentration detector | |
| CN205506739U (en) | Humidity sensor | |
| Cappelli et al. | Battery-less HF RFID sensor tag for soil moisture measurements | |
| CN103293189B (en) | Plant leaf surface humidity sensor and plant leaf surface humidity measurement device | |
| CN202794092U (en) | Metro tunnel concrete crack monitoring device based on flexible conductive coating | |
| Ramadan et al. | Design and implementation of a low cost photovoltaic soil moisture monitoring station for irrigation scheduling with different frequency domain analysis probe structures | |
| CN107389737A (en) | A kind of soil parameters measurement apparatus | |
| Shahadat et al. | Efficient iot based weather station | |
| CN110031667A (en) | Contactless duplex frequency voltage measuring device and its measurement method | |
| CN105717278B (en) | A kind of soil salt cooling-water temperature sensor | |
| Rusu et al. | Miniaturized wireless water content and conductivity soil sensor system | |
| Shigeta et al. | Capacitive-touch-based soil monitoring device with exchangeable sensor probe | |
| CN106932447B (en) | A kind of compound modification method of cultivation matrix water content conductivity | |
| CN205027824U (en) | Electromagnetic radiation monitor | |
| CN109916968B (en) | Accurate measurement method and device of capacitance type grain moisture sensor | |
| CN201803691U (en) | Inside embedded type seam monitoring device based on flexible conductive paint | |
| CN207439502U (en) | A kind of water level sensor based on friction electric induction | |
| CN207516300U (en) | A kind of capacity type soil humidity sensor | |
| CN103693209B (en) | A kind of aircraft corrosive environment monitoring method and implement device thereof | |
| CN115165981A (en) | Formula that flows cereal humidity detection device | |
| CN206832735U (en) | A kind of device of new measurement soil volumetric water content and nutrient solution concentration | |
| CN211123037U (en) | Lightning protection ground resistance detecting system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |