CN104467797B - A kind of two take the safety and gate circuit and its control method using oscillator in two circuits - Google Patents
A kind of two take the safety and gate circuit and its control method using oscillator in two circuits Download PDFInfo
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- CN104467797B CN104467797B CN201410770945.1A CN201410770945A CN104467797B CN 104467797 B CN104467797 B CN 104467797B CN 201410770945 A CN201410770945 A CN 201410770945A CN 104467797 B CN104467797 B CN 104467797B
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Abstract
Of the present invention a kind of two take the safety and gate circuit and its control method using oscillator in two circuits, including isolated voltage up converting circuit one, isolated voltage up converting circuit two, oscillator, safety type relay, isolated boosting transducing circuit, isolated feedback circuit；The input of the isolated voltage up converting circuit one is connected with CPU1 output end, the input of isolated voltage up converting circuit two is connected with CPU2 output end, the output end of the isolated voltage up converting circuit one and isolated voltage up converting circuit two is connected by oscillator with the input of isolated boosting transducing circuit, the output end of isolated boosting transducing circuit is connected with the input of safety type relay, the input of the isolated feedback circuit is connected with the output end of isolated boosting transducing circuit, its output end is connected with the input of isolated boosting transducing circuit.The problem of present invention can preferably solve circuit safety and reliability.
Description
Technical field
The present invention relates to railway signal technology field, and in particular to a kind of two take in two circuits using oscillator safety with
Gate circuit and its control method.
Background technology
The safety that current rail signal field is used is generally divided into two classes with gate circuit, and a class is using two safety electricity
Road, each CPU controls a safety circuit respectively, and each safety circuit controls a relay, passes through the string of two relays
Connection realizes the function of logical "and".The problem of the method can solve the problem that security, but have the disadvantage that the equipment used is more, cost compared with
It is high.An other class is that, using a safety circuit, a safety and one relay of gate control are passed through in two CPU output, this
Method only with a relay, can be effectively reduced cost, but reliability is poor.
The content of the invention
The safety and gate circuit in two circuits using oscillator are taken the technical problem to be solved in the present invention is to provide a kind of two
And its control method, the circuit mainly using transformer and oscillator composition safety and door circuit, can preferably solve peace
The problem of full property and reliability.
In order to solve the above technical problems, the present invention uses following technical scheme：
A kind of two take the safety and gate circuit using oscillator in two circuits, including isolated voltage up converting circuit one, every
From formula voltage up converting circuit two, oscillator, safety type relay, for driving safety type relay and to oscillator and relay
The isolated boosting transducing circuit isolated, for by reduction be input to it is isolated boosting transducing circuit waveform dutycycle come
Reduce the isolated feedback circuit of the circuit output voltage；The input of the isolated voltage up converting circuit one and CPU1's is defeated
Go out end to be connected, the input of isolated voltage up converting circuit two is connected with CPU2 output end, the isolated boost conversion electricity
The output end of road one and isolated voltage up converting circuit two is connected by oscillator with the input of isolated boosting transducing circuit,
The output end of isolated boosting transducing circuit is connected with the input of safety type relay, the input of the isolated feedback circuit
End is connected with the output end of isolated boosting transducing circuit, its output end is connected with the input of isolated boosting transducing circuit；
The isolated voltage up converting circuit one, isolated voltage up converting circuit two, the input difference of isolated boosting transducing circuit
It is connected with a power supply.
The isolated voltage up converting circuit one includes the first metal-oxide-semiconductor, first not be burned for the first metal-oxide-semiconductor of protection
Block isolating circuit, the first step-up transformer of the square-wave signal amplitude for improving CPU1 outputs, and square-wave signal is transformed into admittedly
Determine the sound change-over circuit of high level；The grid of first metal-oxide-semiconductor is connected through the first block isolating circuit with CPU1 output end, the
The source ground of one metal-oxide-semiconductor, the drain electrode of the first metal-oxide-semiconductor is connected with one end of the primary coil of the first step-up transformer, primary line
Another termination power of circle, the secondary coil of first step-up transformer is connected through sound change-over circuit with oscillator.
The isolated boosting transducing circuit includes the second block isolating circuit, the second metal-oxide-semiconductor, the second step-up transformer, rectification
Circuit and the push-pull circuit for driving the second metal-oxide-semiconductor；One end of second block isolating circuit is connected with oscillator, other end warp
Push-pull circuit is connected with the grid of the second metal-oxide-semiconductor, the source ground of second metal-oxide-semiconductor, the drain electrode of the second metal-oxide-semiconductor with second liter
One end of the primary coil of pressure transformer is connected, another termination power of the primary coil, time of second step-up transformer
The level rectified circuit of coil is connected with safety type relay；The output end of the rectification circuit is fed back to through isolated feedback circuit
Between oscillator and the second block isolating circuit.
The oscillator is the astable oscillator that passive device is constituted.
A kind of two take the safety and the control method of gate circuit using oscillator in two circuits, comprise the following steps：
（A）CPU1, CPU2 provide square wave to isolated voltage up converting circuit one and isolated voltage up converting circuit two respectively
Control signal；
（B）When isolated voltage up converting circuit one and the output identical high level of isolated voltage up converting circuit two, shake
Device vibration is swung, safety type relay adhesive exports the oscillator signal of constant frequency；
（C）When isolated voltage up converting circuit one and isolated voltage up converting circuit two export low level or output level not
When identical, oscillator stops oscillation, and safety type relay disconnects, export orientation secure side；
（D）When CPU1, CPU2 break down, oscillator stops oscillation, and safety type relay disconnects, export orientation safety
Side；
（E）When isolated boosting transducing fault, oscillator is stopped oscillation, and safety type relay disconnects, and output is led
To secure side.
The beneficial effects of the invention are as follows：（1）Safety of the present invention can not only be effectively saved circuit board with gate circuit
Space, while reaching the purpose of high security.By using two CPU dynamic square-wave signal as logical "and" input
Signal, CPU can actively stop exporting dynamic square-wave signal, so that export orientation secure side；After cpu fault, output
Automatic guide secure side；If waveforms amplitude, frequency or the dutycycle and another CPU of CPU outputs are inconsistent, output also will
Failure to the safe side side, by the analysis of above cpu fault and output level, effectively increases the safety and reliability of this circuit.
（2）Oscillator 3 is built using passive device, meets internal type failure safe principle, isolated voltage up converting circuit and isolated
Boosting transducing circuit employs step-up transformer, and no-load voltage ratio is more than 4, further increases the reliability and security of circuit.
Brief description of the drawings
Fig. 1 is the integrated circuit block diagram of safety of the present invention and gate circuit；
Fig. 2 is the internal frame diagram of isolated voltage up converting circuit one；
Fig. 3 is isolated boosting transducing circuit internal frame diagram.
Embodiment
The invention will be further described below in conjunction with the accompanying drawings.
As shown in FIG. 1 to 3, the two of the present embodiment take in two circuits using oscillator safety and gate circuit, including every
From formula voltage up converting circuit 1, isolated voltage up converting circuit 22, oscillator 3, safety type relay 5, isolated boosting is changed
Can circuit 4, isolated feedback circuit 6；The input of isolated voltage up converting circuit 1 is connected with CPU1 output end, isolation
The input of formula voltage up converting circuit 22 is connected with CPU2 output end, isolated voltage up converting circuit 1 and isolated boosting
The output end of change-over circuit 22 is connected by oscillator 3 with the input of isolated boosting transducing circuit 4, and isolated boosting is changed
The output end of energy circuit 4 is connected with the input of safety type relay 5, input and the isolated liter of isolated feedback circuit 6
The output end of pressure transducing circuit 4 is connected, its output end is connected with the input of isolated boosting transducing circuit 4；Isolated boosting
Change-over circuit 1, isolated voltage up converting circuit 22, the input of isolated boosting transducing circuit 4 connect respectively power supply one,
Power supply two and power supply three.
The output of oscillator 3 drives safety type relay 5 by isolated boosting transducing circuit 4, safety type relay 5
Normally opened contact provides dry node output, and normally-closed contact is detected for CPU.The characteristics of safety type relay 5 be normally opened contact with it is normally closed
Contact will not be closed at, and CPU1 and CPU2 detects normally-closed contacts by normally-closed contact detection 1 and normally-closed contact detection 2 respectively
State；When normally-closed contact is closed, it is believed that normally opened contact disconnects, and this relay status is corresponding secure side, on the contrary, it is believed that often
The closing of contact is opened, this relay status is corresponding hazardous side, if CPU thinks that relay output state now is mistake
, CPU will stop Dynamic Signal output, disconnect safety type relay 5 so that export orientation secure side.
Oscillator 3 is made up of passive device, is astable oscillator；The frequency of oscillator 3 can be by adjusting electricity
Road parameter is adjusted, and amplitude is the high electricity of output by isolated voltage up converting circuit 1 and isolated voltage up converting circuit 22
Flat decision.The output of oscillator 3 and isolated voltage up converting circuit 1 and the high level of isolated voltage up converting circuit 22
Output has stronger dependence；When the cause not of uniform size of two isolated voltage up converting circuit output levels, oscillator 3 stops
Vibration, export orientation secure side；Oscillator 3 itself meets internal type failure safe principle, when the random devices event in oscillator 3
After barrier, oscillator 3 all will no longer vibrate, export orientation secure side.
The circuit of isolated voltage up converting circuit 1 and isolated voltage up converting circuit 22 is identical, isolated boosting
Change-over circuit 1 includes the first metal-oxide-semiconductor 10, the first block isolating circuit 9, the first step-up transformer 11, and sound change-over circuit 12；The
The grid of one metal-oxide-semiconductor 10 is connected through the first block isolating circuit 9 with CPU1 output end, the source ground of the first metal-oxide-semiconductor 10, first
The drain electrode of metal-oxide-semiconductor 10 is connected with one end of the primary coil of the first step-up transformer 11, another termination power one of primary coil,
The secondary coil of first step-up transformer 11 is connected through sound change-over circuit 12 with oscillator 3.The effect of first block isolating circuit 9 is
Preventing CPU1 fixation high level output causes the permanent conducting of the first metal-oxide-semiconductor 10 to burn out the first metal-oxide-semiconductor 10；First boosting transformation
The higher square-wave signal of voltage magnitude that the CPU1 square-wave signals exported are converted into Amplitude Ration power supply one by device 11, this square-wave signal
It is transformed into fixed high level by sound change-over circuit 12 again, this high level output to oscillator 3；Sound change-over circuit 12 is adopted
Designed with internal type failure safe, any component failure is all without the fixed high level of output, export orientation secure side.
Isolated boosting transducing circuit 4 includes the second block isolating circuit 13, the second metal-oxide-semiconductor 15, the second step-up transformer 16, whole
Current circuit 17 and the push-pull circuit 14 for driving the second metal-oxide-semiconductor 15；One end of second block isolating circuit 13 is connected with oscillator 3,
The other end is connected through push-pull circuit 14 with the grid of the second metal-oxide-semiconductor 15, the source ground of the second metal-oxide-semiconductor 15, the second metal-oxide-semiconductor 15
Drain electrode is connected with one end of the primary coil of the second step-up transformer 16, another termination power of the primary coil, the second boosting
The rectified circuit 17 of secondary coil of transformer 16 is connected with safety type relay 5；The output end of rectification circuit 17 is through isolated
Feedback circuit 6 is connected between the block isolating circuit 13 of oscillator 3 and second.The effect of second block isolating circuit 13 is to prevent oscillator 3
Output fixed level causes the permanent conducting of the second metal-oxide-semiconductor 15 to burn out the second metal-oxide-semiconductor 15, by the signal after the second block isolating circuit 13
It is AC signal, this AC signal driving push-pull circuit 14, push-pull circuit 14 drives the second metal-oxide-semiconductor 15.Second step-up transformer
16 effect is the higher square-wave signal of voltage magnitude that the square-wave signal that oscillator 3 is exported is converted into Amplitude Ration power supply three,
This square-wave signal after rectification circuit 17 by being transformed into fixed high level, this high level fixed driving safety type relay
5.Rectification circuit 17 meets internal type failure safe principle, after any component failure in oscillating circuit, rectification circuit 17
The high level signal of output can not all drive safety type relay 5 so that export orientation secure side.
CPU1 and CPU2 provides dynamic to isolated voltage up converting circuit 1 and isolated voltage up converting circuit 22 respectively
Square-wave signal realizes logical "and" function as control signal, the output of two isolated voltage up converting circuit at oscillator 3,
If there is one to stop the dynamic square-wave signal of output in two CPU, or due to dynamic side can not be exported caused by cpu fault
Ripple signal can all cause the normally opened contact of safety type relay 5 to disconnect, failure to the safe side side.Isolated voltage up converting circuit 1 with
Isolated voltage up converting circuit 22 has been respectively completed isolating between two passages of CPU1 and CPU2, makes CPU1's or CPU2
Failure does not diffuse into the side of oscillator 3.When CPU1 and CPU2 export fixed high level and fixed low level respectively, isolation
Formula voltage up converting circuit 1 is with isolated voltage up converting circuit 22 without high level output, and oscillator 3 can not be vibrated, and output is led
To secure side.The no-load voltage ratio of the transformer used in isolated voltage up converting circuit 1 and isolated voltage up converting circuit 22 is big
In 4, when short trouble occurs for circuit, output end does not have voltage output of 4 times equivalent to input；When isolated boosting turns
Change circuit 1 it is different from the output high level of isolated voltage up converting circuit 22 when, oscillator 3 will not vibrate, export orientation peace
Full side；Isolated voltage up converting circuit 1 and isolated voltage up converting circuit 22 use open loop control mode, if CPU1 with
The square wave frequency or dutycycle of CPU2 outputs are different, and isolated voltage up converting circuit 1 and isolated voltage up converting circuit 22 are defeated
The high level gone out is also by difference, and oscillator 3 will not vibrate, export orientation secure side.When isolated voltage up converting circuit 1 with every
When identical from the level that formula voltage up converting circuit 22 is exported, the oscillator signal of a constant frequency, the frequency of this oscillator signal are exported
Rate is adjustable.
Isolated boosting transducing circuit 4 realizes isolating between safety type relay 5 and oscillator 3, safety-type relay
The failure at the end of device 5 does not diffuse into the end of oscillator 3, when 3 nonoscillatory of oscillator, and fixed high level or low level can not pass through
Isolated boosting transducing circuit 4, export orientation secure side；The no-load voltage ratio for the transformer that isolated boosting transducing circuit 4 is used is more than
4, when occurring short trouble, output end there will not be voltage output of 4 times equivalent to input, and safety type relay 5 will not be inhaled
Close, export orientation secure side.
Isolated feedback circuit 6 can be changed according to the isolated boosting of output voltage regulation of isolated boosting transducing circuit 4
The dutycycle of the energy input square wave of circuit 4, when the output voltage of isolated boosting transducing circuit 4 is too high, isolated feedback electricity
Road 6 causes the dutycycle reduction for being input to the square wave of isolated boosting transducing circuit 4, so as to reduce isolated boosting transducing circuit
4 output voltage；When the output voltage of isolated boosting transducing circuit 4 is too low, isolated feedback circuit 6 does not work.
Embodiment described above is only that the preferred embodiment of the present invention is described, not to the model of the present invention
Enclose and be defined, on the premise of design spirit of the present invention is not departed from, technical side of the those of ordinary skill in the art to the present invention
In various modifications and improvement that case is made, the protection domain that claims of the present invention determination all should be fallen into.
Claims (4)
1. a kind of two take the safety and gate circuit using oscillator in two circuits, it is characterised in that：Including isolated boost conversion
Circuit one (1), isolated voltage up converting circuit two (2), oscillator (3), safety type relay (5), for drive it is safety-type after
Electrical equipment (5) and the isolated boosting transducing circuit (4) isolated to oscillator (3) and relay (5), for defeated by reducing
Enter to isolated boosting transducing circuit (4) waveform duty cycle to reduce the isolated anti-of isolated boosting transducing circuit output voltage
Current feed circuit (6)；The input of the isolated voltage up converting circuit one (1) is connected with CPU1 output end, and isolated boosting turns
Change the input of circuit two (2) with CPU2 output end to be connected, the isolated voltage up converting circuit one (1) and isolated boosting
The output end of change-over circuit two (2) is connected by oscillator (3) with the input of isolated boosting transducing circuit (4), isolated
The output end of boosting transducing circuit (4) is connected with the input of safety type relay (5), the isolated feedback circuit (6)
Input is connected with the output end of isolated boosting transducing circuit (4), its output end is defeated with isolated boosting transducing circuit (4)
Enter end to be connected；The isolated voltage up converting circuit one (1), isolated voltage up converting circuit two (2), isolated boosting transducing electricity
The input on road (4) is connected to a power supply；The isolated voltage up converting circuit one (1) is used for by the first metal-oxide-semiconductor (10)
The first block isolating circuit (9) that the first metal-oxide-semiconductor (10) is not burned is protected, the of the square-wave signal amplitude for improving CPU1 outputs
One step-up transformer (11), and the sound change-over circuit (12) that square-wave signal is transformed into fixed high level is constituted；Described first
The grid of metal-oxide-semiconductor (10) is connected through the first block isolating circuit (9) with CPU1 output end, the source ground of the first metal-oxide-semiconductor (10), the
The drain electrode of one metal-oxide-semiconductor (10) is connected with one end of the primary coil of the first step-up transformer (11), another termination of primary coil
Power supply, the secondary coil of first step-up transformer (11) is connected through sound change-over circuit (12) with oscillator (3).
2. according to claim 1 a kind of two take the safety and gate circuit using oscillator in two circuits, it is characterised in that：
It is described it is isolated boosting transducing circuit (4) by the second block isolating circuit (13), the second metal-oxide-semiconductor (15), the second step-up transformer (16),
Rectification circuit (17) and push-pull circuit (14) composition for driving the second metal-oxide-semiconductor (15)；Second block isolating circuit (13)
One end is connected with oscillator (3), and the other end is connected through push-pull circuit (14) with the grid of the second metal-oxide-semiconductor (15), the 2nd MOS
The source ground of (15) is managed, the drain electrode of the second metal-oxide-semiconductor (15) is connected with one end of the primary coil of the second step-up transformer (16),
Another termination power of the primary coil, the rectified circuit of secondary coil (17) and the safety of second step-up transformer (16)
Type relay (5) is connected；The output end of the rectification circuit (17) through isolated feedback circuit (6) feed back to oscillator (3) and
Between second block isolating circuit (13).
3. according to claim 1 a kind of two take the safety and gate circuit using oscillator in two circuits, it is characterised in that：
The oscillator (3) is the astable oscillator that passive device is constituted.
4. according to claim 1 a kind of two take the safety and the control method of gate circuit using oscillator in two circuits,
It is characterised in that it includes following steps：
(A) CPU1, CPU2 are respectively to isolated voltage up converting circuit one (1) and isolated voltage up converting circuit two (2) provider
Wave control signal；
(B) when isolated voltage up converting circuit one (1) and isolated voltage up converting circuit two (2) output identical high level,
Oscillator (3) vibrates, safety type relay (5) adhesive, exports the oscillator signal of constant frequency；
(C) when isolated voltage up converting circuit one (1) and isolated voltage up converting circuit two (2) output low level or output level
When differing, oscillator (3) stops oscillation, and safety type relay (5) disconnects, export orientation secure side；
(D) when CPU1, CPU2 break down, oscillator (3) stops oscillation, and safety type relay (5) disconnects, export orientation peace
Full side；
(E) when isolated boosting transducing circuit (4) failure, oscillator (3) stops oscillation, and safety type relay (5) disconnects, defeated
Go out failure to the safe side side.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410770945.1A CN104467797B (en) | 2014-12-15 | 2014-12-15 | A kind of two take the safety and gate circuit and its control method using oscillator in two circuits |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410770945.1A CN104467797B (en) | 2014-12-15 | 2014-12-15 | A kind of two take the safety and gate circuit and its control method using oscillator in two circuits |
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| CN104467797A CN104467797A (en) | 2015-03-25 |
| CN104467797B true CN104467797B (en) | 2017-08-25 |
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Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105652771A (en) * | 2016-03-07 | 2016-06-08 | 株洲南车时代电气股份有限公司 | Safety on-off output system |
| CN112564484B (en) * | 2020-11-05 | 2022-04-12 | 北京全路通信信号研究设计院集团有限公司 | High-safety remote emergency switch device based on Internet of things technology and data processing method |
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