CN109653799A - A kind of gas alarm being different from traditional structure and implementation method - Google Patents
A kind of gas alarm being different from traditional structure and implementation method Download PDFInfo
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- CN109653799A CN109653799A CN201811599655.XA CN201811599655A CN109653799A CN 109653799 A CN109653799 A CN 109653799A CN 201811599655 A CN201811599655 A CN 201811599655A CN 109653799 A CN109653799 A CN 109653799A
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- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims abstract description 23
- 230000010355 oscillation Effects 0.000 claims description 7
- 238000012360 testing method Methods 0.000 claims description 4
- 239000003990 capacitor Substances 0.000 description 13
- 239000003245 coal Substances 0.000 description 5
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Classifications
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F17/00—Methods or devices for use in mines or tunnels, not covered elsewhere
- E21F17/18—Special adaptations of signalling or alarm devices
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- 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
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Abstract
The invention discloses a kind of gas alarm for being different from traditional structure and implementation methods comprising a firedamp sensor signal circuit, a reference voltage circuit, a comparator circuit, a positive-feedback circuit, a multivibrator circuit, a sound light alarming circuit.The in-phase end of the firedamp sensor signal circuit connection comparator circuit A1；The reference voltage circuit connects A1 reverse side；The output end of comparator A1 introduces positive feedback to in-phase end by resistor network R2/R1；When gas density increases, firedamp sensor signal circuit output signal voltage reduces, due to the presence of backward dioded D1, D2, the reference edge of hysteresis loop comparator is set to take a turn for the worse with input terminal role, A1 becomes the anti-phase input hysteresis loop comparator for having added reference voltage, resistance-capacitance network of the comparator output terminal between reverse side constitutes a multivibrator circuit together with comparator, and multi-resonant oscillating circuit generates square-wave signal driving warning circuit work, generates sound-light alarm.
Description
Technical field
The present invention relates to a kind of technology of portable gas explosion alarm appliance module different from ordinary structure, especially a kind of differences
The circuit structure for going the work of driving oscillator circuit using the output of comparator circuit in traditional gas alarm, to change
The constructive accounting that original warning circuit is usually made of comparator and oscillator two parts circuit.The design is patent, will
Comparator and oscillator are combined into one, so that comparator circuit be made to have both the function of comparing and vibrate, such gas alarm
Circuit structure is more succinct, cost is cheaper, and working, more stable, sensitivity is higher, not less than being a novel trial.This
The unusual gas alarm circuit structure of kind can also be to implementations reports such as various other environment water levels, temperature, pressure
It is alert.
Background technique
In In Modern Mine enterprise, in order to guarantee the safety of people's property and life, safety devices are it may be said that equiped with arms
Tooth is arrived, wherein gas alarm is a kind of one of most important safety equipment, any one meets in working condition, is big
Moulded coal mine just falls below the occurrence probability of current coal mine gas from explosion minimum just because of being widely used for gas alarm,
So whether the design of gas alarm is advanced, succinct, stable, efficient, it is one of the essential condition for guaranteeing Safety of Coal Mine Production.
If wanting to implement alarm design, usually utilization watt to the gas density of coal mine bottom environment on coalface in practical applications
Non-inverting input terminal of the analog voltage as a general comparator acquired by detection of this sensor to shaft bottom gas density
Voltage, the reverse side of comparator be arranged a changeless reference voltage (in order to realize that electric bridge returns to zero, reference voltage value sometimes
It is adjustable, but after having adjusted zero, still or fixed value, therefore for convenience, it is assumed that a reference value is a fixed value), with
Shaft bottom gas density changes, and firedamp sensor output quantity changes, the sign of the difference of the output quantity and a reference value
Once changing, variation is immediately occurred in the output polarity of comparator, thus the oscillator starting of oscillation that triggering is connected with comparator,
Oscillator signal pushes sound horn.
Therefore usually portable gas explosion alarm appliance circuit is generally made of general comparator circuit and oscillating circuit, the two lacks one
It can not.The advantages of this design is technology maturation, is widely used, but alarm circuit design be not very succinct, design cost compared with
It is high.
Design a unusual portable gas explosion alarm appliance modular circuit, for usual gas alarm design in compare
It can only can make the reference voltage of comparator as the feature of multi-resonant oscillating circuit trigger signal, the design compared with device circuit output value
Value, can the exponentially curvilinear motion with the variation of the output polarity of comparator, thus make the output quantity of firedamp sensor with
Regular variation occurs for the sign that a reference value obtains difference, may finally realize the existing comparator function of comparator, have vibration again
Device function is swung, comparator circuit and pierce circuit are combined into one.
The gas alarm modular circuit can be generally applicable to the alarm of a variety of mineral environments, such as mineral environment in fact
The changes alarm such as water level, temperature, pressure, there is extensive use scope, cost performance is very high.
Summary of the invention
That technical problem to be solved by the invention is to provide a kind of structures is simpler, cost is cheaper, using more
Reliably, the higher gas alarm equipment different from conventional design of sensitivity.
To achieve the above object, the present invention provides a kind of gas alarm for being different from traditional structure and implementation method,
Including a firedamp sensor signal circuit, a reference voltage circuit, a comparator circuit, positive-feedback circuit, one
A multivibrator circuit, a sound light alarming circuit.The output signal of the firedamp sensor signal circuit is by reversely connecting
The diode D2 and resistance R1 connect forms the in-phase end voltage U+ of the comparator circuit A1；The reference voltage circuit generates
Reference signal the reverse side voltage U- of the comparator circuit is formed by the diode D1 of Opposite direction connection；Comparator A1's is defeated
Outlet introduces positive feedback to in-phase end by resistor network R2/R1, and A1 is made to form a hysteresis loop comparator circuit；Gas density increases
Added-time, firedamp sensor signal circuit output signal voltage UAIt reduces, due to the presence of backward dioded D1, D2, makes hysteresis ratio
Reference voltage terminal role compared with device takes a turn for the worse with signal input part role, and comparator A1 becomes one and added the anti-of reference voltage
Mutually input hysteresis loop comparator, this reference voltage is exactly current sensor output signal Voltage UA；Hysteresis loop comparator A1 output
Hold resistance-capacitance network R3/C1 between its inverting input terminal one is constituted together with comparator described in multivibrator circuit,
To make comparator A1 have both oscillation functions and comparing function, the two is combined into one, multi-resonant oscillating circuit generates rectangular wave letter
Number driving warning circuit work, generates sound-light alarm.
The sensor signal circuit, 12V power supply, the compensating end C of firedamp sensor, potentiometer P2, firedamp sensor
Test side D, place of working are sequentially connected in series, and export firedamp sensor signal voltage U from the travelling arm of potentiometer P2A。
The reference voltage circuit, 12V power supply, resistance R5, potentiometer P1, resistance R6, place of working are sequentially connected in series, from current potential
The sliding end outputting reference signal voltage U of device P1B。
Detailed description of the invention
Attached drawing 1, attached drawing 2, attached drawing 3 are used to provide further understanding of the present invention, and are constituted part of this application, attached drawing
1 is traditional alarm circuit structure diagram.Attached drawing 2 is supernormal gas alarm modular circuit electrical schematic diagram.Attached drawing 3
It is the multivibrator key point waveform diagram based on hysteresis loop comparator.
Specific embodiment
The circuit structure brief introduction of traditional gas alarm circuit:
Traditional gas alarm circuit generally comprises comparator circuit and pierce circuit two parts, as shown in Figure 1, the circuit is
One typical traditional alarm circuit, in order not to have repetition with this paper intermediate portions, with a common transformer of industrial and mining enterprises
Overtemperature alarm circuitry instead tradition gas alarm circuit describes, their structures are natively similar in fact.
The circuit is by current transformerSB 1、SB 2It is connected in two phase line of three phase mains, positive temperature coefficient thermistor
RT(sensor) it is immersed in transformer oil.SB 1、SB 2The rectified pipe of the alternating voltage that secondary side inducesVD IRectification, resistanceR 1, capacitorC 1After filtering, there is certain current potential in A point, using this current potential as the base of comparator (operational amplifier uA741)
Quasi- current potential.
After oil temperature increases, the resistance value of RT also increases, and is greater than the 3 foot current potentials (sensor output current potential) of operational amplifier
2 feet (A point, reference potential) current potential, then existsIC 16 feet export high level, make transistorT 1、T 2With capacitorC 2And loudspeaker
The audio frequency oscillator of composition works, and then loudspeaker and Light-emitting diode LED just have issued sound and light alarm signal.
The design for the gas alarm modular circuit that comparator, oscillator are combined into one:
The purpose to be realized of the design is, the firedamp sensor used in the coal mine work area environment for being monitored and being measured
When output voltage drops to reference voltage or less, observation circuit can alarm to the variation with sound and flash of light, Ben Wa
This alarm module circuit forms a comparator using operational amplifier, different from traditional warning circuit, this gas report
The reference edge voltage of comparator in alert circuit can type changes with the change in polarity that comparator exports and exponentially, therefore the operation
Amplifier circuit can play comparator and oscillator simultaneously, and the two is combined into one.Gas alarm modular circuit is electrical
Principle is as shown in Fig. 2.
In fig 2, it can be seen that the circuit system includes firedamp sensor signal circuit, reference voltage circuit, compares
6 modular circuits such as device circuit, positive-feedback circuit, multi-resonant oscillating circuit, sound light alarming circuit.
ResistanceR 5, potentiometerP 1, resistanceR 6The reference voltage generating circuit for constituting measuring bridge, passes throughP 1Adjustable electricity
The balance of bridge；The test side D and compensating end C and potentiometer of firedamp sensorP 2Sensor signal circuit is constituted, is passed throughP 2It can be with
Adjust the sensitivity of alarm.
The diode of reversal connectionD 2And resistanceR 1Sensor signal input circuit is formed, the end A in attached drawing 2 is sensor voltage
Input terminal, the end A voltage enter comparator by sensor signal input circuitA 1Non-inverting input terminal, formed non-inverting input terminalU +
Voltage.
The diode of reversal connectionD 1Reference voltage input circuit is formed, the end B in attached drawing 2 is reference voltage input, B end group
Quasi- voltage passes throughD 1Into comparatorA 1Inverting input terminal, formed inverting input terminalU —Voltage.DiodeD 1Opposite direction connection pair
It is very big to form reference voltage oscillation action.
ResistanceR 4, light emitting diodeD 3Form optical alarm circuit；Transistor T, loudspeaker LS form sound alarm circuit.
Resistor networkR 2/R 1Constitute the positive-feedback circuit of comparator.
Operational amplifierA 1A voltage comparator circuit is constituted, sensor voltage is made comparisons with reference voltage.
By capacitorC 1And resistanceR 3The differential circuit and comparator of compositionA 1Constitute multi-resonant oscillating circuit, comparator output
Constantly overturning, due to diodeD 1Reversal connection, lead to capacitorC 1Charge and discharge are constantly carried out by resistance, form a sawtooth wave vibration
Swing signal.
By amplifierA 1Hysteresis loop comparator is formed with positive feedback network:
Due to voltage comparatorA 1With very high gain, if taken no action to, comparator input voltage was both made to change pole
It is small, it can also make comparator output switching activity, to generate a large amount of switching noise, this alarm circuit is easy to wrong report, is not
What we needed.
In order to avoid there is such case, pass through resistor networkR 2 /R 1It is positive and negative added with one to the non-inverting input terminal of comparator
Network is presented, it is this by operational amplifierA 1The comparator constituted with positive feedback network is hysteresis loop comparator circuit.Here hysteresis
Its hysteresis characteristic of comparator is by resistance ratioR 2/R 1It determines, that is, determines the rising edge threshold voltage of hysteresis loop comparatorU T2With under
Drop is along threshold voltageU T1Value.
Due to amplifierA 1Comparing function and oscillation functions are combined into one, and the design circuit is in normal condition and alarm
In the case of the input terminal role of comparator will take a turn for the worse with reference end role, this special design understands that getting up is not too
It is easy.
Can so it understand in the case where normal condition, that is, mineral environment is not alarmed: sensor output voltageU AIt is stagnant
Return the input terminal of comparator, reference voltageU BIt is the reference voltage input of hysteresis loop comparator, threshold voltage calculating ratio at this moment
It is more complex, and we discuss the state under alarm condition, therefore at this moment the calculating of threshold voltage is omitted.Compare under normal circumstances
High level is exported compared with device, alarm is silent.
Once since gas density rising leads to firedamp sensor output voltageU AValue drops to comparison when normal condition
The failing edge threshold voltage of device, then reduce a dimensionless, the output of comparator are reversed to level "0" immediately, and circuit will be into
Enter alarm condition.
Circuit enters after alarm condition, comparator reverse side voltageU -Due to capacitorC 1Charge and discharge electro ultrafiltration be in oscillation
State, therefore at this moment the input terminal of hysteresis loop comparator becomesU -Voltage, reference edge are reversed toU AVoltage, due to the gas at this moment
Concentration signal is a fixed value, and actually circuit becomes one and " added reference voltage (practical is exactly gas density signal voltage)
Anti-phase input hysteresis loop comparator ", at this moment the threshold voltage of hysteresis loop comparator is found out by the following steps:
It enablesU —=U +, find outU —It is exactly threshold voltage at this moment, therefore obtains:
In above two formulaU CC=12V。
The detailed annotation of the gas alarm circuit alarm course of work
In the normal situation of gas density, comparator output voltage is high level 12V, light emitting diodeD 3It keeps extinguishing shape
State, transistor T cut-off, loudspeaker LS keep quiet sound state.
The increase of gas density leads to sensor output voltageU AIt reduces, comparator output is reversed to low level " 0 ", shines
DiodeD 3It shines；Transistor T is connected, and moment will enter alarm condition by DC voltage, circuit in loudspeaker LS.
Due to light emitting diodeD 3Conducting shines, therefore feedback network R2/R1How much can makeU +Voltage is reduced a bit, makes to compare
The positive feedback depth of device is further deepened.
12V power supply is to capacitorC 1Pass through resistance R3And the output end (6 foot) of comparator charges, since capacitor has
There is the characteristics of end voltage cannot be mutated, is reversed to low level moment, capacitor in comparator outputC 1Lower end voltage (compares
2 foot of device, reverse side voltage) it is maintained as former level, with capacitorC 1The progress of charging, comparator reverse side voltageU -Exponentially
Form reduces, such as the U of Fig. 3-It is shown, whereinU T1、U T2The respectively failing edge of hysteresis loop comparator and rising edge threshold voltage,U+,
WithU+,The respectively corresponding comparator in-phase end voltage of rising edge threshold voltage and failing edge threshold voltage.
With the reduction of comparator reverse side voltage, diodeD 1Cut-off, the voltage (i.e. former reference voltage) at the end B is just no longer
Influence comparator reverse side voltageU --, when comparator reverse sideU --Voltage drops to the threshold voltage found out aboveU T1, then reduce
One dimensionless, the output end of comparator are overturn again as high level 12V, light emitting diode D3Extinguish, transistor T cut-off, loudspeaker
No current passes through in LS.
Due to light emitting diodeD 3Cut-off shines, therefore feedback networkR 2/R 1How much can makeU +Voltage increase a bit, makes to compare
Device positive feedback depth is further deepened.
Comparator output terminal overturning is the moment of high level, capacitorC 1Lower end voltage is maintained as former level, 12v high electricity
It puts down again by resistanceR 3To capacitorC 1Reverse charging is carried out, with capacitorC 1The progress of reverse charging, comparator reverse side electricity
Exponentially form increases pressure.
Comparator reverse sideU --Voltage gradually rises to threshold voltageU T2, when being further added by a dimensionless, comparator is defeated
Outlet is reversed to level "0" again, and light emitting diode is bright again again；Transistor T is connected again, and moment passes through directly again in loudspeaker LS
Galvanic electricity pressure.
So as long as firedamp sensor output voltage (i.e. the end A voltage) is lower than predetermined value, due to Opposite direction connection diodeD 1
Presence, the inverting input terminal voltage of comparatorU --Signal will be vibrated with certain frequency, and light emitting diode is dodged with certain frequency
Light；Transistor T by the pulsed direct current of certain frequency in loudspeaker LS, issues alarm with certain frequency on or off,
Such as Fig. 3.
The period of alarm signal can simply be calculated with following formula:
t≈2R 3 C 1Ln(1+2R 1/R 2)
Wherein t unit is the second；Unit of resistance is ohm；Unit of capacity is farad.
The end of gas alarm alarm procedure:
Gas density restores normal,U AVoltage increases, U+Voltage will also increase, as long as U-Oscillating voltage at a time drop
As low as U+, then when reducing dimensionless, strong positive feedback will make comparator output switching activity high level, due at this moment comparing
" benchmark " of device replaces again with " input " role, comparator constant output high level and no longer vibrate, such as Fig. 3, alarmed
Journey terminates.
This alarm modular circuit passes through dexterously by switching diode D1Then reversal connection utilizes capacitor C1Charge and discharge electric work
Can, so that originally stable reference voltage is become unstable oscillating voltage, which believes by exporting with firedamp sensor
Number comparison, make comparator export square wave oscillation signal.To change original warning circuit usually by comparator and oscillation
The constructive accounting of device two parts circuit composition, is a novel trial.
The design passes through artificial circuit emulation testing, and circuit structure is perfect, component parameters are accurate.
Claims (3)
1. a kind of gas alarm for being different from traditional structure and implementation method comprising a firedamp sensor signal circuit,
One reference voltage circuit, a comparator circuit, a positive-feedback circuit, a multivibrator circuit, an acousto-optic report
Alert circuit；The output signal of the firedamp sensor signal circuit forms institute by the diode D2 and resistance R1 of Opposite direction connection
State the in-phase end voltage U+ of comparator circuit A1；The reference signal that the reference voltage circuit generates passes through two poles of Opposite direction connection
Pipe D1 forms the reverse side voltage U- of the comparator circuit；The output end of comparator A1 passes through resistor network R2/R1 Xiang Tongxiang
End introduces positive feedback, and A1 is made to form a hysteresis loop comparator circuit；When gas density increases, the output of firedamp sensor signal circuit
Signal voltage reduces, and due to the presence of backward dioded D1, D2, occurs that the reference edge of hysteresis loop comparator with input terminal role inverse
Turn, comparator A1 becomes the anti-phase input hysteresis loop comparator for having added reference voltage, this reference voltage is exactly current biography
Sensor output signal voltage UA；Resistance-capacitance network R3/C1 of the hysteresis loop comparator A1 output end between reverse side is together with comparator
The two is closed two so that comparator A1 be made to have both oscillation functions and comparing function by multivibrator circuit described in constituting one
It is one, multi-resonant oscillating circuit generates square-wave signal and drives the warning circuit work, generates sound-light alarm.
2. a kind of gas alarm for being different from traditional structure according to claim 1 and implementation method, it is characterised in that:
The sensor signal circuit, 12V power supply, the compensating end C of firedamp sensor, potentiometer P2, firedamp sensor test side D,
Place of working is sequentially connected in series, and exports firedamp sensor signal voltage U from the travelling arm of potentiometer P2A。
3. a kind of gas alarm for being different from traditional structure according to claim 1 and implementation method, it is characterised in that:
The reference voltage circuit, 12V power supply, resistance R5, potentiometer P1, resistance R6, place of working are sequentially connected in series, from the cunning of potentiometer P1
Moved end outputting reference signal voltage UB。
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811599655.XA CN109653799B (en) | 2018-12-26 | 2018-12-26 | Gas alarm different from traditional structure and implementation method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811599655.XA CN109653799B (en) | 2018-12-26 | 2018-12-26 | Gas alarm different from traditional structure and implementation method |
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| CN109653799A true CN109653799A (en) | 2019-04-19 |
| CN109653799B CN109653799B (en) | 2023-12-22 |
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|---|---|---|---|---|
| US3359429A (en) * | 1964-03-23 | 1967-12-19 | Tektronix Inc | Trigger generator circuit having synchronized astable input oscillator |
| CN2175439Y (en) * | 1993-07-11 | 1994-08-24 | 石宝 | Non-contact electronic buzzing and flashing device |
| KR20010091653A (en) * | 2000-03-17 | 2001-10-23 | 곽정소 | Charging control circuit of battery in automobile |
| US20150054550A1 (en) * | 2013-08-20 | 2015-02-26 | Semiconductor Energy Laboratory Co., Ltd. | Signal processing device, and driving method and program thereof |
| CN205714289U (en) * | 2016-04-27 | 2016-11-23 | 北京联合大学 | Portable gas explosion transfinites monitor |
| CN206671415U (en) * | 2017-03-27 | 2017-11-24 | 山西工程技术学院 | LED indicator type tri-state voltage alarms |
| CN209483427U (en) * | 2018-12-26 | 2019-10-11 | 山西工程技术学院 | A kind of supernormal portable gas explosion alarm appliance |
-
2018
- 2018-12-26 CN CN201811599655.XA patent/CN109653799B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3359429A (en) * | 1964-03-23 | 1967-12-19 | Tektronix Inc | Trigger generator circuit having synchronized astable input oscillator |
| CN2175439Y (en) * | 1993-07-11 | 1994-08-24 | 石宝 | Non-contact electronic buzzing and flashing device |
| KR20010091653A (en) * | 2000-03-17 | 2001-10-23 | 곽정소 | Charging control circuit of battery in automobile |
| US20150054550A1 (en) * | 2013-08-20 | 2015-02-26 | Semiconductor Energy Laboratory Co., Ltd. | Signal processing device, and driving method and program thereof |
| CN205714289U (en) * | 2016-04-27 | 2016-11-23 | 北京联合大学 | Portable gas explosion transfinites monitor |
| CN206671415U (en) * | 2017-03-27 | 2017-11-24 | 山西工程技术学院 | LED indicator type tri-state voltage alarms |
| CN209483427U (en) * | 2018-12-26 | 2019-10-11 | 山西工程技术学院 | A kind of supernormal portable gas explosion alarm appliance |
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