CN207018226U - A kind of ac fan state detection circuit and device - Google Patents
A kind of ac fan state detection circuit and device Download PDFInfo
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- CN207018226U CN207018226U CN201720279262.5U CN201720279262U CN207018226U CN 207018226 U CN207018226 U CN 207018226U CN 201720279262 U CN201720279262 U CN 201720279262U CN 207018226 U CN207018226 U CN 207018226U
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Abstract
The utility model provides a kind of ac fan state detection circuit and device, using the vice-side winding of current transformer, change-over circuit, the first comparison circuit and the first isolation circuit are passed sequentially through, is connected with the microprocessor for issuing fan operation control instruction, realizes the current detecting of ac fan；Using wind pressure sensor, the second comparison circuit and the second isolation circuit are passed sequentially through, is connected with microprocessor, realize the blast detection of ac fan；The fan that electric current, blast and the microprocessor of the microprocessor combination ac fan are issued runs control instruction, judgement obtains the carrying out practically state of ac fan, when avoiding individually carrying out ac fan condition adjudgement with current detecting, because threshold value comparison voltage is difficult to select, cause circuit easily caused erroneous judgement.
Description
Technical field
It the utility model is related to current transformer ac fan state inspection field, more particularly to a kind of ac fan state
Detect circuit and device.
Background technology
Radiating instrument of the ac fan as main flow, has a very wide range of applications in modern industrial production, and it runs
State radiates most important to interiors of products.Especially in the application scenarios of current transformer, with carrying for current transformer power density
Height, the real-time monitoring of current transformer internal heat dissipating situation become more important.
Currently used ac fan state-detection scheme is current detection scheme, and it is mainly by detecting alternating current
Stream, and whether the DC voltage for the alternating current obtain after rectification sampling is compared, judge magnitude of voltage V in just
(V1 in normal scope<V<V2), it is finally reached the purpose of ac fan state observation.
But the program, when being sampled to low current, its precision is difficult to control, the DC voltage V for sampling to obtain is difficult to
It is accurate to determine, and then cause its threshold value comparison voltage V1, V2 to be difficult to select, cause circuit easily to produce erroneous judgement.
Utility model content
The utility model provides a kind of ac fan state detection circuit and device, to solve easily to produce in the prior art
The problem of erroneous judgement.
To achieve the above object, the technical scheme that the application provides is as follows：
A kind of ac fan state detection circuit, including：Current transformer, change-over circuit, the first comparison circuit, first every
From circuit, wind pressure sensor, the second comparison circuit and the second isolation circuit；Wherein：
The vice-side winding of the current transformer, pass sequentially through the change-over circuit, first comparison circuit and described
First isolation circuit, it is connected with the microprocessor for issuing fan operation control instruction；
The wind pressure sensor, second comparison circuit and second isolation circuit are passed sequentially through, with micro- place
Reason device is connected.
Preferably, the change-over circuit includes：Rectification circuit, filter circuit and amplifying circuit；
The exchange end of the rectification circuit is connected with the vice-side winding of the current transformer；
The DC terminal of the rectification circuit is connected by the filter circuit with the input of the amplifying circuit；
The output end of the amplifying circuit is connected with first comparison circuit.
Preferably, the amplifying circuit includes：First resistor, second resistance, 3rd resistor, the 4th resistance and operation amplifier
Device；Wherein：
One end of the first resistor is connected with one end of the filter circuit and the DC terminal positive pole of the rectification circuit,
Tie point is connected by the second resistance with the in-phase end of the operational amplifier；
The other end of the other end of the first resistor and the filter circuit, the DC terminal negative pole of the rectification circuit and
First reference ground is connected, and tie point is connected by the 3rd resistor with the end of oppisite phase of the operational amplifier；
The end of oppisite phase of the operational amplifier is connected by the 4th resistance with the output end of the operational amplifier.
Preferably, first comparison circuit includes：5th resistance, the 6th resistance and first comparator；Wherein：
One end of 5th resistance is connected with the output end of the change-over circuit；
The other end of 5th resistance is connected with the positive input terminal of the first comparator；
The negative input end of the first comparator receives reference voltage signal；
The output end of the first comparator is connected by the 6th resistance with power supply；
The output end of the first comparator is the output end of first comparison circuit.
Preferably, second comparison circuit includes：7th resistance, the 8th resistance and the second comparator；Wherein：
One end of 8th resistance is connected with power supply；
The other end of 8th resistance respectively with the output end of the wind pressure sensor and second comparator just
Input is connected；
The negative input end of second comparator receives reference voltage signal；
The output end of second comparator is connected by the 7th resistance with the power supply；
The output end of second comparator is the output end of second comparison circuit.
Preferably, first isolation circuit includes：First isolating device and the tenth resistance；First isolating device
Output head anode is connected by the tenth resistance with power supply, the negative pole of output end and the second reference ground of first isolating device
It is connected, the output head anode of first isolating device is connected with the microprocessor；
Second isolation circuit includes：Second isolating device and the 9th resistance；The output end of second isolating device
Positive pole is connected by the 9th resistance with the power supply, the negative pole of output end of second isolating device and the described second reference
Ground is connected, and the output head anode of second isolating device is connected with the microprocessor.
Preferably, first isolating device and second isolating device are relay；The input of the relay
End negative pole is connected with the first reference ground；
Or first isolating device and second isolating device are optocoupler；The input cathode of the optocoupler is led to
Resistance is crossed with first reference ground to be connected.
A kind of ac fan condition checkout gear, including：Microprocessor any described as described above exchanges with least one
Fan state detection circuit.
Preferably, in addition to：Encoder；
The input of the encoder and the output of the output end and second isolation circuit of first isolation circuit
End is connected；
The output end of the encoder is connected with the microprocessor.
Preferably, in addition to：Piece selects chip；
Described is selected the defeated of the input of chip and the output end of first isolation circuit and second isolation circuit
Go out end to be connected；
Described is selected the output end of chip to be connected with the microprocessor.
The ac fan state detection circuit and device provided by the utility model, using current transformer secondary around
Group, change-over circuit, the first comparison circuit and the first isolation circuit are passed sequentially through, the microprocessor with issuing fan operation control instruction
Device is connected, and realizes the current detecting of ac fan；Using wind pressure sensor, the second comparison circuit and the second isolation electricity are passed sequentially through
Road, it is connected with microprocessor, realizes the blast detection of ac fan；Enable the electricity of the microprocessor combination ac fan
The fan operation control instruction that stream, blast and microprocessor issue, judgement obtain the carrying out practically state of ac fan, avoided
When individually carrying out ac fan condition adjudgement with current detecting, because threshold value comparison voltage is difficult to select, circuit is caused easily to produce
Raw erroneous judgement.
Brief description of the drawings
, below will be to embodiment in order to illustrate more clearly of the technical scheme in the utility model embodiment or prior art
Or the required accompanying drawing used is briefly described in description of the prior art, it should be apparent that, below description in accompanying drawing only
It is some embodiments of the utility model, for those of ordinary skill in the art, is not paying the premise of creative work
Under, other accompanying drawings can also be obtained according to these accompanying drawings.
Fig. 1 is the structural representation for the ac fan condition checkout gear that the utility model embodiment provides；
Fig. 2 is the circuit diagram for the ac fan condition checkout gear that another embodiment of the utility model provides；
Fig. 3 is the circuit diagram for the ac fan condition checkout gear that another embodiment of the utility model provides；
Fig. 4 is the structural representation for the ac fan condition checkout gear that another embodiment of the utility model provides.
Embodiment
Below in conjunction with the accompanying drawing in the embodiment of the present application, the technical scheme in the embodiment of the present application is carried out clear, complete
Site preparation describes, it is clear that described embodiment is only some embodiments of the present application, rather than whole embodiments.It is based on
Embodiment in the application, those of ordinary skill in the art are obtained every other under the premise of creative work is not made
Embodiment, belong to the scope of the application protection.
The utility model provides a kind of ac fan state detection circuit, to solve easily to produce erroneous judgement in the prior art
The problem of.
Referring to Fig. 1, the ac fan state detection circuit, including：Current transformer 101, change-over circuit 102, first compare
Compared with circuit 103, the first isolation circuit 104, wind pressure sensor 201, the second comparison circuit 202 and the second isolation circuit 203；Its
In：
The vice-side winding of current transformer 101, pass sequentially through change-over circuit 102, the first comparison circuit 103 and first every
From circuit 104, it is connected with the microprocessor for issuing fan operation control instruction；
Wind pressure sensor 201, the second comparison circuit 202 and the second isolation circuit 203 are passed sequentially through, with microprocessor phase
Even.
Specifically operation principle is：
After radiating element (such as current transformer) operation, fan operation control instruction is issued by microprocessor, then exchanges wind
Fan brings into operation.
Now, induced-current will be produced on the vice-side winding of current transformer 101, is converted to by change-over circuit 102
Magnitude of voltage, the magnitude of voltage in the first comparison circuit 103 compared with threshold voltage after, by the first isolation circuit 104
Isolation and amplifier, obtain the whether normal conclusion of electric current of ac fan.
Meanwhile wind pressure sensor 201 detects the blast of ac fan, and pass through the ratio of follow-up second comparison circuit 202
Compared with the isolation and amplifier with the second isolation circuit 203, whether the blast for obtaining ac fan reaches the conclusion of requirement.
Finally whether reach the conclusion of requirement by the whether normal conclusion of electric current of microprocessor combination ac fan, blast
And the fan operation control instruction that microprocessor issues, judgement obtain the carrying out practically state of ac fan.Microprocessor is also
Can be according to specific application environment, output order protects the same of current transformer to control current transformer to shut down after setting certain failure
When, staff can be easy to be safeguarded.
What deserves to be explained is, it is contemplated that in start and stop moment, its blast reaches requirement and time delay T be present ac fan, because
This state-detection of ac fan can be set by microprocessor t (>T) the continuous detection of time judges.
The ac fan state detection circuit that the present embodiment provides, using the vice-side winding of current transformer 101, successively
By change-over circuit 102, the first comparison circuit 103 and the first isolation circuit 104, micro- place with issuing fan operation control instruction
Reason device is connected, and realizes the current detecting of ac fan；Using wind pressure sensor 201, the second comparison circuit 202 and are passed sequentially through
Two isolation circuits 203, are connected with microprocessor, realize the blast detection of ac fan；The microprocessor is combined to hand over
The fan operation control instruction that electric current, blast and the microprocessor of flow fan issue, judgement obtain the specific fortune of ac fan
Row state, when avoiding individually carrying out ac fan condition adjudgement with current detecting, because threshold value comparison voltage is difficult to select, cause
Circuit easily caused erroneous judgement.
In addition, the scheme of ac fan condition adjudgement is individually carried out with current detecting in the prior art, due to different exchanges
The output current size difference of fan is larger, needs build-out resistor again when causing to carry out state-detection for different ac fans
Parameter, so that its output voltage meets to require, therefore, the program does not have versatility.
And the ac fan state detection circuit that the present embodiment provides, the threshold voltage in the first comparison circuit 103 are adopted
With the smaller numerical value more than zero, you can embody ac fan and whether there is electric current；Without to 102 turns of change-over circuit
The magnitude of voltage changed is accurately compared, and therefore, the ac fan state detection circuit that the present embodiment provides has versatility, energy
The ac fan of enough compatible different sizes.
Furthermore in the prior art individually with current detecting carry out ac fan condition adjudgement scheme, when wind field occur it is low/
During high voltage crossing, the abnormal electrical power supply of ac fan power supply is likely to result in, and then causes the current anomaly of ac fan, is caused
Ac fan condition adjudgement malfunctions.
And the ac fan state detection circuit that the present embodiment provides, even if because low high voltage ride-through occurs for wind field,
Cause the abnormal electrical power supply of ac fan power supply, its microprocessor can yet combine ac fan the whether normal conclusion of blast,
And microprocessor issue fan operation control instruction, judgement obtain the carrying out practically state of ac fan, avoid individually with
Current detecting carries out the easily caused judgement error in this case of ac fan condition adjudgement.
The utility model provides a kind of specific ac fan state detection circuit, in above-described embodiment and Fig. 1 base
On plinth, referring to Fig. 2 and Fig. 3, the change-over circuit 102 in Fig. 1 includes：Rectification circuit 121, filter circuit 122 and amplifying circuit
123；
The exchange end of rectification circuit 121 is connected with the vice-side winding of current transformer 101；
The DC terminal of rectification circuit 121 is connected by filter circuit 122 with the input of amplifying circuit 123；
The output end of amplifying circuit 123 is connected with the first comparison circuit 103.
Preferably, include referring to Fig. 2 and Fig. 3, amplifying circuit 123：First resistor R1, second resistance R2,3rd resistor
R3, the 4th resistance R4 and operational amplifier A 1；Wherein：
First resistor R1 one end is connected with one end of filter circuit 122 and the DC terminal positive pole of rectification circuit 121, connection
Point is connected by second resistance R2 with the in-phase end of operational amplifier A 1；
The first resistor R1 other end and the other end of filter circuit 122, the DC terminal negative pole and first of rectification circuit 121
Reference ground GND1 is connected, and tie point is connected by 3rd resistor R3 with the end of oppisite phase of operational amplifier A 1；
The end of oppisite phase of operational amplifier A 1 is connected by the 4th resistance R4 with the output end of operational amplifier A 1.
Preferably, include referring to Fig. 2 and Fig. 3, the first comparison circuit 103：5th resistance R5, the 6th resistance R6 and the first ratio
Compared with device A2；Wherein：
5th resistance R5 one end is connected with the output end of change-over circuit 102；
The 5th resistance R5 other end is connected with first comparator A2 positive input terminal；
First comparator A2 negative input end receives reference voltage signal V；
First comparator A2 output end is connected by the 6th resistance R6 with power supply；
First comparator A2 output end is the output end of the first comparison circuit 103.
Preferably, include referring to Fig. 2 and Fig. 3, the second comparison circuit 202：7th resistance R7, the 8th resistance R8 and the second ratio
Compared with device A3；Wherein：
8th resistance R8 one end is connected with power supply VCC；
The 8th resistance R8 other end respectively with the output end of wind pressure sensor 201 and the second comparator A3 positive input
End is connected；
Second comparator A3 negative input end receives reference voltage signal V；
Second comparator A3 output end is connected by the 7th resistance R7 with power supply；
Second comparator A3 output end is the output end of the second comparison circuit 202.
Preferably, include referring to Fig. 2 and Fig. 3, the first isolation circuit 104：First isolating device and the tenth resistance；First every
Output head anode from device is connected by the tenth resistance R10 with power supply VCC, the negative pole of output end of the first isolating device and second
Reference ground GND2 is connected, and the output head anode of the first isolating device is connected with microprocessor；
Second isolation circuit 203 includes：Second isolating device and the 9th resistance R9；The output head anode of second isolating device
It is connected by the 9th resistance R9 with power supply VCC, the negative pole of output end of the second isolating device is connected with the second reference ground GND2, and second
The output head anode of isolating device is connected with microprocessor.
In specific practical application, the first isolating device and the second isolating device can be relay, such as Fig. 3 institutes
Show；The input cathode of relay is connected with the first reference ground GND1；
Or first isolating device and the second isolating device be optocoupler, as shown in Figure 2；The input cathode of optocoupler is led to
Resistance is crossed with the first reference ground GND1 to be connected.
Specifically operation principle is：
It is N current transformer 101 when ac fan is run to use the former secondary turn ratio, and sensing is produced by its vice-side winding
Electric current；After the rectified rectification of circuit 121 of alternating current and filter circuit 122 on vice-side winding filter, in first resistor R1 two
The in-phase end that direct current sampled voltage U1 is input to operational amplifier A 1 is established at end；3rd resistor R3, the 4th resistance R4 are matched to straight
Stream sampled voltage U1 is amplified processing, the voltage U2=U1 after amplification × (1+R4/R3)；When ac fan normal operation, block up
When turning, there is electric current to flow through in vice-side winding, now there is U2>V (V values are smaller, more than 0), the input anode of the first isolation circuit 104
Input as high level, the output of its output head anode is low level 0；When ac fan normally disconnects, opened a way, vice-side winding is without electricity
Stream flows through, now U2<V, the input of the input anode of the first isolation circuit 104 are low level, and the output of its output head anode is high electricity
Flat 1.
When ac fan blast reaches requirement, wind pressure sensor 201 is rendered as high-impedance state, now wind pressure sensor 201
Output voltage U3>V, the input of the input anode of the second isolation circuit 203 are high level, and the output of its output head anode is low level
0；When ac fan blast not up to requires, wind pressure sensor 201 is rendered as on-state, now the output of wind pressure sensor 201
Voltage U3<V, the input of the input anode of the second isolation circuit 203 are low level, and the output of its output head anode is high level 1.
With reference to fan operation control instruction and the output signal of two isolation circuits, exchange as shown in table 1 can be listed
Fan-status truth table：
The ac fan state truth table of table 1
The ac fan state truth table with reference to shown in table 1, you can judging ac fan, specifically there occurs which kind of failure.Its
Remaining operation principle and above-described embodiment system, are no longer repeated one by one herein.
Another embodiment of the utility model additionally provides a kind of ac fan condition checkout gear, referring to Fig. 1, including：It is micro-
Processor and at least one ac fan state detection circuit as described in above-mentioned embodiment is any.
Preferably, referring to Fig. 4, the ac fan condition checkout gear on Fig. 1 basis, in addition to：Encoder or
Person's piece selects chip；
Encoder or piece select the input of chip and the output end of the first isolation circuit 104 and the second isolation circuit 203
Output end be connected；
Encoder or piece select the output end of chip to be connected with microprocessor.
Encoder or piece select chip can be with least two ac fan state detection circuits (in such as Fig. 4 in dotted line frame
It is shown) it is connected, receiving corresponding output signal, (each ac fan state detection circuit has two output signals, respectively hands over
Whether the whether normal conclusion of the electric current of flow fan, the blast of ac fan reach the conclusion of requirement), each output signal is entered
Row coding, then delivers to microprocessor by encoded signal again, by microprocessor judge in the continuous t times each output signal with
The fan operation control instruction that microprocessor issues corresponds to situation, you can judges the current state of each ac fan.
When ac fan number is more, chip is selected to carry out the output signal of ac fan state detection circuit using piece
Coding, required occupancy I/O port resource during more ac fan operations can be greatly reduced.Combined again by the signal in microprocessor
Parsing, can fast and effective specific any the platform ac fan of identification break down classification, be easy to safeguard, beneficial to application.
Remaining operation principle is same as the previously described embodiments, no longer repeats one by one herein.
Each embodiment is described by the way of progressive in the utility model, what each embodiment stressed be and its
The difference of his embodiment, between each embodiment identical similar portion mutually referring to.For dress disclosed in embodiment
For putting, because it is corresponded to the method disclosed in Example, so description is fairly simple, related part is referring to method part
Explanation.
It is described above, only it is preferred embodiment of the present utility model, not the utility model is made any formal
Limitation.Although the utility model is disclosed above with preferred embodiment, but it is not limited to the utility model.It is any ripe
Those skilled in the art is known, in the case where not departing from technical solutions of the utility model ambit, all using the side of the disclosure above
Method and technology contents make many possible changes and modifications to technical solutions of the utility model, or be revised as equivalent variations etc.
Imitate embodiment.Therefore, every content without departing from technical solutions of the utility model, according to the technical essence of the utility model to
Any simple modifications, equivalents, and modifications that upper embodiment is done, still fall within the model of technical solutions of the utility model protection
In enclosing.
Claims (10)
- A kind of 1. ac fan state detection circuit, it is characterised in that including：Current transformer, change-over circuit, the first comparison are electric Road, the first isolation circuit, wind pressure sensor, the second comparison circuit and the second isolation circuit；Wherein：The vice-side winding of the current transformer, pass sequentially through the change-over circuit, first comparison circuit and described first Isolation circuit, it is connected with the microprocessor for issuing fan operation control instruction；The wind pressure sensor, second comparison circuit and second isolation circuit are passed sequentially through, with the microprocessor It is connected.
- 2. ac fan state detection circuit according to claim 1, it is characterised in that the change-over circuit includes：It is whole Current circuit, filter circuit and amplifying circuit；The exchange end of the rectification circuit is connected with the vice-side winding of the current transformer；The DC terminal of the rectification circuit is connected by the filter circuit with the input of the amplifying circuit；The output end of the amplifying circuit is connected with first comparison circuit.
- 3. ac fan state detection circuit according to claim 2, it is characterised in that the amplifying circuit includes：The One resistance, second resistance, 3rd resistor, the 4th resistance and operational amplifier；Wherein：One end of the first resistor is connected with one end of the filter circuit and the DC terminal positive pole of the rectification circuit, connection Point is connected by the second resistance with the in-phase end of the operational amplifier；The other end, the DC terminal negative pole and first of the rectification circuit of the other end of the first resistor and the filter circuit Reference ground is connected, and tie point is connected by the 3rd resistor with the end of oppisite phase of the operational amplifier；The end of oppisite phase of the operational amplifier is connected by the 4th resistance with the output end of the operational amplifier.
- 4. ac fan state detection circuit according to claim 1, it is characterised in that the first comparison circuit bag Include：5th resistance, the 6th resistance and first comparator；Wherein：One end of 5th resistance is connected with the output end of the change-over circuit；The other end of 5th resistance is connected with the positive input terminal of the first comparator；The negative input end of the first comparator receives reference voltage signal；The output end of the first comparator is connected by the 6th resistance with power supply；The output end of the first comparator is the output end of first comparison circuit.
- 5. ac fan state detection circuit according to claim 1, it is characterised in that the second comparison circuit bag Include：7th resistance, the 8th resistance and the second comparator；Wherein：One end of 8th resistance is connected with power supply；The other end of 8th resistance respectively with the output end of the wind pressure sensor and the positive input of second comparator End is connected；The negative input end of second comparator receives reference voltage signal；The output end of second comparator is connected by the 7th resistance with the power supply；The output end of second comparator is the output end of second comparison circuit.
- 6. ac fan state detection circuit according to claim 1, it is characterised in that the first isolation circuit bag Include：First isolating device and the tenth resistance；The output head anode of first isolating device passes through the tenth resistance and power supply It is connected, the negative pole of output end of first isolating device is connected with the second reference ground, and the output of first isolating device is rectified Pole is connected with the microprocessor；Second isolation circuit includes：Second isolating device and the 9th resistance；The output head anode of second isolating device It is connected by the 9th resistance with the power supply, the negative pole of output end of second isolating device and the second reference ground phase Even, the output head anode of second isolating device is connected with the microprocessor.
- 7. ac fan state detection circuit according to claim 6, it is characterised in that first isolating device and institute It is relay to state the second isolating device；The input cathode of the relay is connected with the first reference ground；Or first isolating device and second isolating device are optocoupler；The input cathode of the optocoupler passes through electricity Resistance is connected with first reference ground.
- A kind of 8. ac fan condition checkout gear, it is characterised in that including：Microprocessor and at least one such as claim 1 To 7 any described ac fan state detection circuits.
- 9. ac fan condition checkout gear according to claim 8, it is characterised in that also include：Encoder；The input of the encoder and the output end of first isolation circuit and the output end phase of second isolation circuit Even；The output end of the encoder is connected with the microprocessor.
- 10. ac fan condition checkout gear according to claim 8, it is characterised in that also include：Piece selects chip；Described is selected the input of chip and the output end of first isolation circuit and the output end of second isolation circuit It is connected；Described is selected the output end of chip to be connected with the microprocessor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720279262.5U CN207018226U (en) | 2017-03-21 | 2017-03-21 | A kind of ac fan state detection circuit and device |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720279262.5U CN207018226U (en) | 2017-03-21 | 2017-03-21 | A kind of ac fan state detection circuit and device |
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| CN207018226U true CN207018226U (en) | 2018-02-16 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113030775A (en) * | 2021-03-04 | 2021-06-25 | 武汉理工大学 | System and method for detecting state of machine tool signal lamp |
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2017
- 2017-03-21 CN CN201720279262.5U patent/CN207018226U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113030775A (en) * | 2021-03-04 | 2021-06-25 | 武汉理工大学 | System and method for detecting state of machine tool signal lamp |
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