CN109387261A - A kind of non-contact capacitive induction type liquid level sensor - Google Patents
A kind of non-contact capacitive induction type liquid level sensor Download PDFInfo
- Publication number
- CN109387261A CN109387261A CN201710689003.4A CN201710689003A CN109387261A CN 109387261 A CN109387261 A CN 109387261A CN 201710689003 A CN201710689003 A CN 201710689003A CN 109387261 A CN109387261 A CN 109387261A
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- Prior art keywords
- circuit
- resistance
- trigger
- liquid level
- electrically connected
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F23/00—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm
- G01F23/22—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water
- G01F23/26—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water by measuring variations of capacity or inductance of capacitors or inductors arising from the presence of liquid or fluent solid material in the electric or electromagnetic fields
- G01F23/263—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water by measuring variations of capacity or inductance of capacitors or inductors arising from the presence of liquid or fluent solid material in the electric or electromagnetic fields by measuring variations in capacitance of capacitors
- G01F23/266—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water by measuring variations of capacity or inductance of capacitors or inductors arising from the presence of liquid or fluent solid material in the electric or electromagnetic fields by measuring variations in capacitance of capacitors measuring circuits therefor
Abstract
A kind of non-contact capacitive induction type liquid level sensor, including tablet and PCB circuit board, tablet is electrically connected with PCB circuit board, and the circuit in PCB circuit board includes fixed frequency oscillating circuit, reference level threshold set circuit, input circuit, liquid level sensor circuit, reverse phase Schmidt trigger, filter circuit and output circuit；The power end of reverse phase Schmidt trigger is electrically connected with Vcc power end, the ground terminal ground connection of reverse phase Schmidt trigger；The present invention can be effectively prevented the normal work of noise signal interference circuit, enhance anti-interference ability, improve the accuracy of level sensing, detection process is simple and fast according to above content.
Description
Technical field
The present invention relates to sensor field more particularly to a kind of non-contact capacitive induction type liquid level sensors.
Background technique
Traditional capacitance level transducer has that electrode is exposed in water, and water changes interelectrode capacitor as medium, from
And the variation of sensed water level；Traditional water resistance type liquid level sensor, there is multiple electrodes, but when water did not had electrode, electrode it
Between there is faint electric current to flow through, thus sensed water level change；If above two sensor be applied to temperature is higher, water quality compared with
In the water of difference, it is easier to which fouling covers electrode and detection is caused to be failed, and anti-interference ability is weak, the liquid of magnetic float and tongue tube type
Level sensor also can be stuck because tying full water dirt on float, leads to level sensing failure.
Summary of the invention
It is an object of the invention to propose a kind of non-contact capacitive induction type liquid level sensor, it effectively prevent noise jamming electric
The normal work on road enhances anti-interference ability, improves the accuracy of measurement liquid level.
To achieve this purpose, the present invention adopts the following technical scheme:
A kind of non-contact capacitive induction type liquid level sensor, including tablet and PCB circuit board, the tablet and the PCB
Circuit board electrical connection,
Circuit in the PCB circuit board include fixed frequency oscillating circuit, reference level threshold set circuit, input circuit,
Liquid level sensor circuit, reverse phase Schmidt trigger, filter circuit and output circuit；
The reverse phase Schmidt trigger includes inverter trigger M1, M2, M3, M4, M5 and M6, the reverse phase Schmidt trigger
Power end be electrically connected with Vcc power end, the ground terminal of reverse phase Schmidt trigger ground connection；
Wherein, Vcc plant-grid connection reverse phase Schmidt trigger, the fixed frequency oscillating circuit access the reverse phase Schmidt touching
Device is sent out, the reference level threshold set circuit is linked into fixed frequency oscillating circuit, and the input circuit is linked into the base
Quasi- level threshold initialization circuit, the liquid sensor circuit is linked into the input circuit, and the liquid level sensed is believed
It number is input to the reverse phase Schmidt trigger, the reverse phase Schmidt trigger carries out calculation process to liquid level signal and will fortune
It calculates result and is transmitted to filter circuit, operation result is transmitted to output circuit from filter circuit again.
Further, the fixed frequency oscillating circuit includes inverter trigger M1, inverter trigger M2, resistance R6, capacitor
C5, diode D1 and resistance R5；
The output end of the inverter trigger M1 is electrically connected with one end of the capacitor C5, the other end of the capacitor C5, reverse phase
The anode electrical connection of the input terminal of trigger M2, one end of resistance R6 and diode D1, the output end of the inverter trigger M2,
One end of the input terminal of the inverter trigger M1, the other end of the resistance R6 and the resistance R5 is electrically connected, the resistance
The electrical connection of the cathode of the other end of R5 and the diode D1.
Further, the reference level threshold set circuit is composed in series by resistance R7 and semifixed resistor Rv1.
Further, the input circuit includes resistance R8, R10 and thermistor Rt9, the resistance R8 and thermistor
After Rt9 is electrically connected in series, then it is electrically connected with the resistance R10 parallel connection.
Further, the filter circuit includes the first filter circuit and the second filter circuit；The first filter circuit packet
Diode D2, resistance R11 and capacitor C6 are included, second filter circuit includes resistance R12 and capacitor C7；
The anode of the diode D2 and the output end of inverter trigger M3 are electrically connected, cathode, the resistance R11 of the diode D2
One end, capacitor C6 one end and inverter trigger M4 input terminal electrical connection, the R11 the other end ground connection, the capacitor
The other end of C6 is electrically connected with Vcc power end, one end electrical connection of the output end and R12 of the inverter trigger M4, the electricity
Hinder the input terminal electrical connection of the other end of R12, one end of capacitor C7 and inverter trigger M5, another termination of the resistance C7
Ground.
It further, further include having working indicating comprising resistance R13 and Light-emitting diode LED 1, the resistance R13
One end and the inverter trigger M4 output end electrical connection, the other end of the resistance R13 and the light emitting diode
The anode electrical connection of LED1, the cathode ground connection of the Light-emitting diode LED 1.
Further, the output circuit includes inverter trigger M5, M6, resistance R4, R3 and transistor Q1,
The output end of the inverter trigger M5 is electrically connected with the input terminal of the inverter trigger M6, the inverter trigger M6
Output end be electrically connected with one end of the resistance R4；
The other end of the resistance R4 is electrically connected with the base stage of the transistor Q1, the emitter ground connection of the transistor Q1, institute
The collector for stating transistor Q1 is electrically connected with one end of the resistance R3, and the other end of the resistance is electrically connected with power Vcc end.
Further, the trimmer potentiometer 3 for adjusting reference level value is additionally provided in the PCB circuit board.
Further, the tablet 1 separates with the PCB circuit board 5 places.
Further, the tablet 1 and fill insulant in the compartment of PCB circuit board 5.
The normal work of noise signal interference circuit can be effectively prevented according to above content in the present invention, enhances anti-dry
Ability is disturbed, the accuracy of measurement liquid level is improved.
Detailed description of the invention
Fig. 1 is the structural schematic diagram of the one of embodiment of the present invention.
Fig. 2 is schematic block circuit diagram of the invention.
Fig. 3 is circuit diagram of the invention.
Fig. 4 is the schematic diagram of present invention detection liquid level.
Wherein: tablet 1, trimmer potentiometer 3, work light 4, PCB circuit board 5, container 6, non-connects insulation crust 2
Touch capacitance induction type liquid level sensor 7, liquid level line 8.
Specific embodiment
To further illustrate the technical scheme of the present invention below with reference to the accompanying drawings and specific embodiments.
As shown in Figure 1, a kind of non-contact capacitive induction type liquid level sensor, including tablet 1 and PCB circuit board 5, it is described
Tablet 1 and the PCB circuit board 5 are installed in insulation crust 2, and the tablet 1 is electrically connected with the PCB circuit board 5,
As shown in Fig. 2, the circuit in the PCB circuit board 5 includes fixed frequency oscillating circuit, reference level threshold value setting electricity
Road, input circuit, liquid level sensor circuit, reverse phase Schmidt trigger, filter circuit and output circuit；
The reverse phase Schmidt trigger includes inverter trigger M1, M2, M3, M4, M5 and M6, the reverse phase Schmidt trigger
Power end be electrically connected with Vcc power end, the ground terminal of reverse phase Schmidt trigger ground connection；
Wherein, Vcc plant-grid connection reverse phase Schmidt trigger, the fixed frequency oscillating circuit access the reverse phase Schmidt touching
Device is sent out, the reference level threshold set circuit is linked into fixed frequency oscillating circuit, and the input circuit is linked into the base
Quasi- level threshold initialization circuit, the liquid sensor circuit is linked into the input circuit, and the liquid level sensed is believed
It number is input to the reverse phase Schmidt trigger, the reverse phase Schmidt trigger carries out calculation process to liquid level signal and will fortune
It calculates result and is transmitted to filter circuit, operation result is transmitted to output circuit from filter circuit again.
The reverse phase Schmidt trigger, feature are there are two stable state, and state is maintained by input signal current potential；It is right
Successively decreasing in negative sense has different threshold voltages with the input signal of positive incremental two kinds of different change directions, Schmidt trigger；
The two threshold voltages are referred to as forward threshold voltage Vt+ and negative sense threshold voltage vt-.In input signal from low level
The changed input voltage of circuit state is set to be known as forward threshold voltage Vt+ during being raised to high level, in input signal
From high level drop to it is low level during so that the changed input voltage of circuit state is known as negative sense threshold voltage vt-.
Therefore；This process makes Schmidt trigger circuit form a lag area because there is the two critical voltages, can be effectively prevented
The normal work of noise jamming circuit in hysteresis range, enhances anti-interference ability.
It further include having capacitor C4, one end is electrically connected with the power end of the reverse phase Schmidt trigger, other end ground connection,
The capacitor C4 plays decoupling, Vcc plant-grid connection reverse phase Schmidt trigger, after powering on, the fixed frequency oscillating circuit
The level signal of generation is transmitted to the reference level threshold set circuit, can trigger the level signal amplitude just and is touching
Within the scope of the negative threshold value Vt- of inverter trigger, this value is transmitted to input electricity as reference level value, then the level signal
Level signal is transmitted to liquid level sensor circuit by road, input circuit, is formed between container and medium to the tablet 1 induction
Capacitor charge, and this level signal feedback that will charge is to the reverse phase Schmidt trigger, the reverse phase Schmidt
Trigger carries out calculation process to the level signal that feeds back and operation result is transmitted to filter circuit, operation result again from
Filter circuit is transmitted to output circuit, realizes the detection of liquid level, and whole process is simple and reliable, and accuracy is high.
As shown in figure 4, being installed on container 6 when using a kind of non-contact capacitive induction type liquid level sensor for the first time
Outside, then 1 center of tablet powers on close to detected liquid level line 8, carry out level sensing；When the material of the container 6
When matter, wall thickness change, the reference level threshold set circuit is adjusted, resets reference level value, then carry out liquid level
Detection.It is tested through experiment, it can be achieved that 0 when a kind of non-contact capacitive induction type liquid level sensor of the present invention is tested
Level sensing in~30mm left and right thickness container 6, a kind of non-contact capacitive induction type liquid level sensor 0 DEG C~
The data stabilization measured within the scope of 70 DEG C, and without departing from detected range.
Further, as shown in figure 3, the fixed frequency oscillating circuit includes inverter trigger M1, inverter trigger M2, electricity
Hinder R6, capacitor C5, diode D1 and resistance R5；
The output end of the inverter trigger M1 is electrically connected with one end of the capacitor C5, the other end of the capacitor C5, reverse phase
The anode electrical connection of the input terminal of trigger M2, one end of resistance R6 and diode D1, the output end of the inverter trigger M2,
One end of the input terminal of the inverter trigger M1, the other end of the resistance R6 and the resistance R5 is electrically connected, the resistance
The electrical connection of the cathode of the other end of R5 and the diode D1.
The capacitor C5 is the precision capacitance of NOP material, and thermal stability is fine, and environment temperature influences very its capacitance
It is small；The resistance R6 is the precision resistance of patch, and error is within ± 1%；Therefore the inverter trigger M1, the reverse phase
Trigger M2, the resistance R6 and the capacitor C5 form level signal caused by the oscillator of fixed frequency and stablize, environment
Temperature is little to influencing, and the level signal is more stable after the adjusting of the diode D1 and the resistance R5.
Further, as shown in figure 3, the reference level threshold set circuit is by resistance R7 and semifixed resistor Rv1 series connection group
At.
The semifixed resistor Rv1 is glass glaze material, the high-accuracy semifixed resistor spirally adjusted, and thermal stability is fine,
Environment temperature influences very little, the reference level threshold value being composed in series by the resistance R7 and the semifixed resistor Rv1 to its resistance value
Initialization circuit is simple and reliable, it can carry out amplitude adjusting to level signal caused by the fixed frequency oscillating circuit, makes institute
The amplitude for stating level signal just can trigger within the scope of the negative threshold value Vt- of touching inverter trigger, and by the electricity after adjusting amplitude
Ordinary mail number is used as reference level value；When the material of measured object, thickness change, it is only necessary to adjust the semifixed resistor Rv1's
Resistance value can change the reference level value, convenient and reliable.
Further, as shown in figure 3, the input circuit include resistance R8, R10 and thermistor Rt9, the resistance R8 and
After thermistor Rt9 is electrically connected in series, then it is electrically connected with the resistance R10 parallel connection.
The thermistor Rt9 is the element of a negative temperature coefficient, has temperature compensation function to circuit, uses thermistor
Rt9 realizes temperature-compensating, simple and fast, after the resistance R8 and thermistor Rt9 are electrically connected in series, then with the resistance R10
Parallel connection electrical connection is played the role of protecting circuit.
Further, as shown in figure 3, the filter circuit includes the first filter circuit and the second filter circuit；Described first
Filter circuit includes diode D2, resistance R11 and capacitor C6, and second filter circuit includes resistance R12 and capacitor C7；
The anode of the diode D2 and the output end of inverter trigger M3 are electrically connected, cathode, the resistance R11 of the diode D2
One end, capacitor C6 one end and inverter trigger M4 input terminal electrical connection, the R11 the other end ground connection, the capacitor
The other end of C6 is electrically connected with Vcc power end, one end electrical connection of the output end and R12 of the inverter trigger M4, the electricity
Hinder the input terminal electrical connection of the other end of R12, one end of capacitor C7 and inverter trigger M5, another termination of the resistance C7
Ground.
The filter circuit plays a filtering role, the induction of tablet 1 in liquid level sensor circuit be formed in container and medium it
Between capacitor charge, this level signal that charges feedback is triggered by the reverse phase to the reverse phase Schmidt trigger
After the calculation process of device M3, the level signal is transmitted to first filter circuit, carries out level-one filtering；Level-one filtering knot
Shu Hou, then the level signal is transmitted to the inverter trigger M4, after the calculation process of the inverter trigger M4,
The level signal is transmitted to second filter circuit again, the clutter quilt after two stage filter, in the level signal
It filters out, so that the level signal of output to the output circuit is more steady accurate.
Further, as shown in figure 3, further including having working indicating comprising resistance R13 and Light-emitting diode LED 1,
The electrical connection of the output end of one end of the resistance R13 and the inverter trigger M4, the other end and the hair of the resistance R13
The anode electrical connection of optical diode LED1, the cathode ground connection of the Light-emitting diode LED 1, as shown in Figure 1, the light-emitting diodes
Pipe LED1 is the work light 4 of Fig. 1 meaning.
After level-one filters, the work is also transmitted to by the level signal that the inverter trigger M4 is handled and is indicated
Circuit makes the diode (LED) 1 work, and uses as instruction is worked normally, and the resistance R13 plays metering function, protects the hair
Optical diode LED1.
Further, as shown in figure 3, the output circuit includes inverter trigger M5, M6, resistance R4, R3 and transistor Q1,
The output end of the inverter trigger M5 is electrically connected with the input terminal of the inverter trigger M6, the inverter trigger M6
Output end be electrically connected with one end of the resistance R4；
The other end of the resistance R4 is electrically connected with the base stage of the transistor Q1, the emitter ground connection of the transistor Q1, institute
The collector for stating transistor Q1 is electrically connected with one end of the resistance R3, and the other end of the resistance is electrically connected with power Vcc end.
After two stage filter, the level signal is transmitted to the inverter trigger M5, after operation, the level letter
Number it is transmitted to the inverter trigger M6, after operation, the level signal exports electric to the output by the resistance R4
Road, the resistance R4 play metering function, and the resistance R3 is the load resistance of the transistor Q1, play the protection output electricity
The effect on road, the level signal is exported from OUT terminal, to realize the detection of liquid level.
Further, as shown in Figure 1, being additionally provided with the trimmer potentiometer 3 for adjusting reference level value in the PCB circuit board.
When the material of measured object, thickness change, the semifixed resistor is adjusted by adjusting the trimmer potentiometer 3
The resistance value of Rv1, so that the reference level value can be changed, it is convenient and efficient, reliable and stable.
Further, as shown in Figure 1, the tablet 1 and the PCB circuit board 5 separate placement, the PCB circuit is reduced
Plate 5 improves the precision of detection to the electric jamming of the tablet 1.
Further, the tablet 1 and fill insulant in the compartment of PCB circuit board 5, are further reduced institute
PCB circuit board 5 is stated to the electric jamming of the tablet 1, improves the precision of detection.
The technical principle of the invention is described above in combination with a specific embodiment.These descriptions are intended merely to explain of the invention
Principle, and shall not be construed in any way as a limitation of the scope of protection of the invention.Based on the explanation herein, the technology of this field
Personnel can associate with other specific embodiments of the invention without creative labor, these modes are fallen within
Within protection scope of the present invention.
Claims (10)
1. a kind of non-contact capacitive induction type liquid level sensor, it is characterised in that: described including tablet 1 and PCB circuit board 5
Tablet 1 is electrically connected with the PCB circuit board 5,
It is characterized by: the circuit in the PCB circuit board 5 includes fixed frequency oscillating circuit, reference level threshold value setting electricity
Road, input circuit, liquid level sensor circuit, reverse phase Schmidt trigger, filter circuit and output circuit；
The reverse phase Schmidt trigger includes inverter trigger M1, M2, M3, M4, M5 and M6, the reverse phase Schmidt trigger
Power end be electrically connected with Vcc power end, the ground terminal of reverse phase Schmidt trigger ground connection；
Wherein, Vcc plant-grid connection reverse phase Schmidt trigger, the fixed frequency oscillating circuit access the reverse phase Schmidt touching
Device is sent out, the reference level threshold set circuit is linked into fixed frequency oscillating circuit, and the input circuit is linked into the base
Quasi- level threshold initialization circuit, the liquid sensor circuit is linked into the input circuit, and the liquid level sensed is believed
It number is input to the reverse phase Schmidt trigger, the reverse phase Schmidt trigger carries out calculation process to liquid level signal and will fortune
It calculates result and is transmitted to filter circuit, operation result is transmitted to output circuit from filter circuit again.
2. a kind of non-contact capacitive induction type liquid level sensor according to claim 1, it is characterised in that: the fixed frequency
Rate oscillating circuit includes inverter trigger M1, inverter trigger M2, resistance R6, capacitor C5, diode D1 and resistance R5；
The output end of the inverter trigger M1 is electrically connected with one end of the capacitor C5, the other end of the capacitor C5, reverse phase
The anode electrical connection of the input terminal of trigger M2, one end of resistance R6 and diode D1, the output end of the inverter trigger M2,
One end of the input terminal of the inverter trigger M1, the other end of the resistance R6 and the resistance R5 is electrically connected, the resistance
The electrical connection of the cathode of the other end of R5 and the diode D1.
3. a kind of non-contact capacitive induction type liquid level sensor according to claim 1, it is characterised in that: the benchmark electricity
Flat threshold set circuit is composed in series by resistance R7 and semifixed resistor Rv1.
4. a kind of non-contact capacitive induction type liquid level sensor according to claim 1, it is characterised in that: the input electricity
After road includes resistance R8, R10 and thermistor Rt9, the resistance R8 and thermistor Rt9 be electrically connected in series, then with the electricity
Hinder R10 parallel connection electrical connection.
5. a kind of non-contact capacitive induction type liquid level sensor according to claim 1, it is characterised in that: the filtered electrical
Road includes the first filter circuit and the second filter circuit；First filter circuit includes diode D2, resistance R11 and capacitor
C6, second filter circuit include resistance R12 and capacitor C7；
The anode of the diode D2 and the output end of inverter trigger M3 are electrically connected, cathode, the resistance R11 of the diode D2
One end, capacitor C6 one end and inverter trigger M4 input terminal electrical connection, the R11 the other end ground connection, the capacitor
The other end of C6 is electrically connected with Vcc power end, one end electrical connection of the output end and R12 of the inverter trigger M4, the electricity
Hinder the input terminal electrical connection of the other end of R12, one end of capacitor C7 and inverter trigger M5, another termination of the resistance C7
Ground.
6. a kind of non-contact capacitive induction type liquid level sensor according to claim 5, it is characterised in that: further include having work
Make indicating circuit comprising resistance R13 and Light-emitting diode LED 1, one end of the resistance R13 and the inverter trigger M4
Output end electrical connection, the anode of the other end of the resistance R13 and the Light-emitting diode LED 1 is electrically connected, described luminous two
The cathode of pole pipe LED1 is grounded.
7. a kind of non-contact capacitive induction type liquid level sensor according to claim 1, it is characterised in that: the output electricity
Road includes inverter trigger M5, M6, resistance R4, R3 and transistor Q1,
The output end of the inverter trigger M5 is electrically connected with the input terminal of the inverter trigger M6, the inverter trigger M6
Output end be electrically connected with one end of the resistance R4；
The other end of the resistance R4 is electrically connected with the base stage of the transistor Q1, the emitter ground connection of the transistor Q1, institute
The collector for stating transistor Q1 is electrically connected with one end of the resistance R3, and the other end of the resistance is electrically connected with power Vcc end.
8. a kind of non-contact capacitive induction type liquid level sensor according to claim 1, it is characterised in that: the PCB electricity
The trimmer potentiometer 3 for adjusting reference level value is additionally provided on the plate of road.
9. a kind of non-contact capacitive induction type liquid level sensor according to claim 1, it is characterised in that: the tablet
1 separates placement with the PCB circuit board 5.
10. a kind of non-contact capacitive induction type liquid level sensor according to claim 9, it is characterised in that: the induction
Fill insulant in the compartment of plate 1 and PCB circuit board 5.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710689003.4A CN109387261A (en) | 2017-08-13 | 2017-08-13 | A kind of non-contact capacitive induction type liquid level sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710689003.4A CN109387261A (en) | 2017-08-13 | 2017-08-13 | A kind of non-contact capacitive induction type liquid level sensor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN109387261A true CN109387261A (en) | 2019-02-26 |
Family
ID=65415616
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710689003.4A Withdrawn CN109387261A (en) | 2017-08-13 | 2017-08-13 | A kind of non-contact capacitive induction type liquid level sensor |
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| Country | Link |
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| CN (1) | CN109387261A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113750418A (en) * | 2021-09-03 | 2021-12-07 | 南京机电职业技术学院 | Reliable strategy for automatic control of Internet of things equipment based on bus mode |
-
2017
- 2017-08-13 CN CN201710689003.4A patent/CN109387261A/en not_active Withdrawn
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113750418A (en) * | 2021-09-03 | 2021-12-07 | 南京机电职业技术学院 | Reliable strategy for automatic control of Internet of things equipment based on bus mode |
| CN113750418B (en) * | 2021-09-03 | 2022-12-02 | 南京机电职业技术学院 | Reliable strategy for automatic control of Internet of things equipment based on bus mode |
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Application publication date: 20190226 |