CN110130967B - Device and method for preventing gas from exceeding limit by local ventilator guarantee technology - Google Patents
Device and method for preventing gas from exceeding limit by local ventilator guarantee technology Download PDFInfo
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- CN110130967B CN110130967B CN201910230732.2A CN201910230732A CN110130967B CN 110130967 B CN110130967 B CN 110130967B CN 201910230732 A CN201910230732 A CN 201910230732A CN 110130967 B CN110130967 B CN 110130967B
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- 238000005516 engineering process Methods 0.000 title claims abstract description 17
- 238000000034 method Methods 0.000 title claims abstract description 13
- 238000001514 detection method Methods 0.000 claims abstract description 12
- 230000001012 protector Effects 0.000 claims description 7
- 230000008878 coupling Effects 0.000 claims description 3
- 238000010168 coupling process Methods 0.000 claims description 3
- 238000005859 coupling reaction Methods 0.000 claims description 3
- 239000003245 coal Substances 0.000 abstract description 5
- 238000004880 explosion Methods 0.000 description 5
- 238000013024 troubleshooting Methods 0.000 description 5
- 238000009412 basement excavation Methods 0.000 description 3
- 238000012423 maintenance Methods 0.000 description 3
- 230000001681 protective effect Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 230000005611 electricity Effects 0.000 description 2
- 238000009413 insulation Methods 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 230000005641 tunneling Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000013021 overheating Methods 0.000 description 1
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Classifications
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- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F1/00—Ventilation of mines or tunnels; Distribution of ventilating currents
- E21F1/006—Ventilation at the working face of galleries or tunnels
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D25/00—Pumping installations or systems
- F04D25/16—Combinations of two or more pumps ; Producing two or more separate gas flows
- F04D25/166—Combinations of two or more pumps ; Producing two or more separate gas flows using fans
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D27/00—Control, e.g. regulation, of pumps, pumping installations or pumping systems specially adapted for elastic fluids
- F04D27/008—Stop safety or alarm devices, e.g. stop-and-go control; Disposition of check-valves
Abstract
The invention is suitable for the technical field of coal mine safety, and provides a device and a method for preventing gas overrun by a local ventilator guarantee technology, wherein the device comprises an air connection switch and a detection circuit, wherein a first wiring port and a second wiring port are led out from a control loop of the air connection switch; detection circuitry includes main office switch, relay, reserve office switch, contactor and gas substation relay, main office switch and reserve office switch all with second wiring port series connection through establishing ties a set of relay at reserve office switch, when losing electric when out of work with reserve office, the power failure does not actuation can appear in its relay, makes maintainer can discover fast, can the rapid judgement electrical equipment that establishes ties with the relay breaks down simultaneously, has avoided reserve office fan switch JDB to damage and can not in time discover to handle and the button contact point harmfully can not in time discover to handle the scheduling problem.
Description
Technical Field
The invention belongs to the technical field of coal mine safety, and particularly relates to a device and a method for preventing gas overrun by a local ventilator guarantee technology.
Background
The gas explosion has a certain concentration range, and the concentration range in which the gas in the air can cause explosion after encountering fire is called as a gas explosion limit. The limit of gas explosion is 5-16%, and the gas overrun means that the gas concentration of the operation sites such as coal mine excavation working faces exceeds the gas concentration specified in coal mine safety regulations, and people must be stopped and removed immediately, and the risk operation is absolutely not allowed. If the gas concentration of the coal face reaches 1%, an alarm is required, and if the gas concentration reaches or exceeds 1.5%, the power is cut off and people are removed immediately.
At present, the types of local ventilator switches used on a tunneling working face are mostly QBZ-120SF, and a main local fan switch auxiliary contact is adopted to lock a wind linkage switch control loop, so that serious hidden danger exists. 1. When the main local fan switch is in fault, the standby local fan switch is not electrified to cause the shutdown of the local ventilator and the gas overrun accident. 3. The spare fan switch JDB can not be timely found to have hidden trouble when being damaged. 4. The damage of the protective tube or the intermediate relay can not be found and processed in time, 4, the bad contact point of the button can not be found and processed in time, 5, the main office fan is used for locking the power electricity, when the standby office has a fault, the power electricity can not be found in time, and the high voltage of the power supply and the main office share one bus.
Disclosure of Invention
The invention provides a device and a method for preventing gas overrun by a local ventilator guarantee technology, aiming at solving the problems that the type of a local ventilator switch used on the current tunneling working face is mostly QBZ-120SF, a main local fan switch auxiliary contact is adopted to lock a wind linkage switch control loop, and the situation that 1, the power failure of a spare local fan switch cannot be found in time exists. 2. When the main local fan switch is in fault, the standby local fan switch is not electrified to cause the shutdown of the local ventilator, and the gas is in an over-limit accident. 3. The spare fan switch JDB can not be timely found to have hidden trouble when being damaged. 4. Damage to the fuse or intermediate relay cannot be detected and processed in time. 4. And 5, the problem that the poor contact point of the button cannot be found in time by locking the power supply by using the main office fan, and when the standby office breaks down, the problem cannot be found in time.
The invention is realized in such a way, the device and the method for preventing the gas overrun of the local ventilator guarantee technology comprise an air linked switch and a detection circuit, wherein a first wiring port and a second wiring port are led out from a control loop of the air linked switch;
detection circuitry includes main office switch, relay, reserve office switch, contactor and gas substation relay, main office switch and reserve office switch all with second wiring port series connection, relay, reserve office switch, contactor and gas substation relay series connection in proper order, main office switch with contactor and gas substation relay series connection, main office switch with relay and reserve office switch parallel connection, gas substation relay with first wiring port series connection.
The invention also provides a preferable mode, and the relay is an alternating current relay.
The invention also provides a preferable mode, the main office switch and the standby office switch are both time relays, and the on-off time periods of the main office switch and the standby office switch are opposite.
Preferably, the detection circuit further includes a main office fan and a standby office fan, the main office fan is connected in series between the main office switch and the contactor, the standby office fan is connected in series between the standby office switch and the contactor, and the main office fan and the standby office fan are connected in parallel.
The invention also provides a preferable mode, wherein the driving motors of the main office fan and the standby office fan are both fixedly provided with JDG motor comprehensive protectors.
The invention also provides a preferable mode, and the contactor is a vacuum alternating current contactor.
The invention also provides a preferable mode, and the QBZ-120SF switch is selected as the wind joint switch.
The invention also provides a preferable mode, the main office switch is connected with a manual switch and a standby time relay in parallel, and the manual switch is connected with the standby time relay in series.
The invention also provides a preferable mode, and the on-off time period of the standby time relay is opposite to the on-off time period of the main office switch.
The invention also provides the following preferable concrete steps:
s1: when the relay does not attract the latching air coupling switch to be powered on, whether a power supply is normally connected or not is checked, no voltage is input into the local fan, and the local fan cannot normally operate;
s2: checking that the isolating switch is not normally opened to cause no voltage input of the spare office fan, so that the spare office fan cannot normally run;
s3: checking whether the fuse tube is fused or not or the contact is poor, so that the voltage cannot be normally input into the spare fan, and the spare fan cannot normally run;
s4: and checking whether the spare fan motor protector is damaged or not to cause open circuit, so that the relay can not be normally attracted when being powered off.
S5: checking whether a coil in the relay is burnt out or not, so that the relay cannot be normally attracted when being electrified;
s6: and checking whether the insulativity of a motor for driving the spare fan is low or not, so that a coil in the motor is short-circuited, and the relay cannot be normally electrified and closed.
Compared with the prior art, the invention has the beneficial effects that: the invention relates to a method for preventing gas overrun of ventilator guarantee technology, which respectively controls the work of a main office fan and a standby office fan by connecting a main office switch and a standby office switch in parallel, and avoids the series connection of the main office switch and the standby office switch at present, when the main office switch is in fault, the standby office switch is out of power and stops the operation of a local ventilator, so that a gas overrun accident is easy to occur.
Drawings
FIG. 1 is a schematic circuit diagram of the present invention;
fig. 2 is a schematic diagram of the circuit connection of multiple sets of main office fans and standby office fans according to the present invention.
In the figure: 1-wind connection switch, 11-first connection port, 12-second connection port, 2-detection circuit, 21-main office switch, 22-relay, 23-standby office switch, 24-contactor, 25-gas substation relay, 26-main office fan, 27-standby office fan, 28-manual switch and 29-standby time relay.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Referring to fig. 1-2, the present invention provides a technical solution: a device and a method for preventing gas overrun in a local ventilator guarantee technology comprise an air connection switch 1 and a detection circuit 2, wherein a first wiring port 11 and a second wiring port 12 are led out from a control loop of the air connection switch 1;
In the embodiment, the main office switch 21 and the spare office switch 23 are connected in parallel, so that the work of the main office fan 26 and the spare office fan 27 is controlled respectively, the current series connection of the main office switch 21 and the spare office switch 23 is avoided, when the main office switch 26 has a fault, the spare office fan 27 has no power, the local ventilator is shut down, and a gas overrun accident is easy to occur, a group of relays 22 are connected in series with the spare office switch 23, when equipment in the same series circuit with the spare office switch 23 has a fault, the relays 22 are powered off and do not attract, so that maintenance personnel only need to perform troubleshooting and maintenance on the equipment in the same series circuit with the spare office switch 23, and the time for troubleshooting is shortened.
Further, the relay 22 is an ac relay 22.
In the present embodiment, the relay 22 is an ac relay 22, and the ac relay 22 is used for normal use in an ac circuit.
Further, the master switch 21 and the standby switch 23 are both time relays 22, and the on-off time periods of the master switch 21 and the standby switch 23 are opposite.
In this embodiment, the master switch 21 and the standby switch 23 are both time relays 22, the on/off time periods of the master switch 21 and the standby switch 23 are opposite, and the two sets of time relays 22 with opposite periods can ensure that the master switch 21 and the standby switch 23 can be alternately powered on, so as to ensure the alternate operation of the master fan 26 and the standby fan 27.
Further, detection circuitry 2 still includes main office fan 26 and spare office fan 27, main office fan 26 series connection in main office switch 21 with between contactor 24, spare office fan 27 series connection in spare office switch 23 with between contactor 24, main office fan 26 with spare office fan 27 parallel connection.
In the present embodiment, the main office fan 26 and the backup office fan 27 are operated to extract and discharge the gas on the excavation face, thereby avoiding the occurrence of the gas overrun accident on the excavation face.
Further, the driving motors of the main office fan 26 and the standby office fan 27 are both fixedly provided with JDG motor comprehensive protectors.
In this embodiment, the motor may be warned and protected when overload, phase loss, rotation blockage, short circuit, overvoltage, undervoltage, leakage, three-phase imbalance, overheating, bearing wear, and stator/rotor eccentricity occur, so as to remind the working fuel to drive the main office fan 26 and the standby office fan 27 to cause the above-mentioned failure.
Furthermore, the wind joint switch 1 is a QBZ-120SF switch.
In the embodiment, the QBZ-120SF switch has good explosion-proof performance and can be used under mine wells with combustion and explosion prohibition.
Further, the main office switch 21 is connected in parallel with a manual switch 28 and a standby time relay 29, the manual switch 28 is connected in series with the standby time relay 29, and the on-off time period of the standby time relay 29 is opposite to the on-off time period of the main office switch 21.
In this embodiment, when the standby fan 27 stops working due to a fault, the user can turn on the manual switch 28, and the standby time relay 29 is powered on, so that the standby time relay 29 and the main switch 21 are alternately powered on the main fan 26, thereby ensuring that the main fan 26 continuously works, and avoiding that the gas is not checked in time due to the fault of the standby fan 27, and the gas is over-limited.
Further, the method comprises the following specific steps:
s1: when the relay 22 does not attract the locking air coupling switch to be powered on, whether the power supply is normally connected is checked, no voltage is input to the local fan, and the local fan cannot normally operate;
s2: checking that the isolating switch is not normally opened to cause no voltage input of the spare office fan, so that the spare office fan cannot normally run;
s3: checking whether the fuse tube is fused or not or the contact is poor, so that the voltage cannot be normally input into the standby fan 27, and the standby fan cannot normally operate;
s4: checking whether the spare fan motor protector is damaged or not to cause open circuit, so that the relay 22 is powered off and can not be normally attracted;
s5: checking whether a coil in the relay 22 is burnt out or not, so that the relay 22 cannot be normally attracted when being electrified;
s6: whether the insulation of the motor for driving the spare fan 27 is low or not is checked, so that the short circuit of the coil in the motor is caused, and the relay 22 cannot be electrified and closed normally.
In this embodiment, when the relay 22 does not attract the latching air-link switch to power on, the maintenance personnel can perform troubleshooting through the above steps, so that the standby office fan 27 can be quickly maintained, the speed of recovering the normal use of the standby office fan 27 is increased, the troubleshooting time is reduced, and meanwhile, the fault of part of equipment (such as a motor protector and a motor which are low) can be predicted.
The working principle and the using process of the invention are as follows: after the invention is installed, the manual switch 28 is in a normally open state, when the relay 22 is not attracted, the fault of the serial circuit with the spare office fan 27 can be judged, then the maintainer can check whether the power supply is normally connected, check whether the isolating switch is not normally opened, whether the protective tube is fused or not in poor contact, and whether the motor protector of the spare office fan 27 is damaged, so that the power supply is automatically cut off, whether the coil in the relay 22 is burnt out, so that the relay 22 cannot be normally attracted when being electrified or the motor insulation for driving the spare office fan 27 is low, and the like, meanwhile, the problems at the checking position are correspondingly processed and maintained, when the corresponding problems are processed, the relay 22 can be attracted to be electrified, so that the spare office fan 27 is normally electrified and works, meanwhile, in the overhauling process, the maintainer can open the manual switch 28, and when the time spare relay 29 is electrified and works, the main office fan 26 is powered on again to make the main office fan 26 powered on again, because the standby time relay 29 is opposite to the on-off time period of the main office switch 21, when the manual switch 28 is turned on, the standby time relay 22 and the main office switch 21 are alternatively powered on for the main office fan 26, thereby ensuring the main office fan 26 to be powered on continuously, avoiding the gas on the driving working surface from being discharged in time due to the shutdown of the standby office fan 27 to cause a gas overrun accident, and simultaneously, the main office fan 26 can be observed to normally run by turning on the manual switch 28, thereby judging whether the standby office fan 27 is shutdown or not caused by the reasons that the power supply is not normally connected and the protective tube is fused or the contact is not, further improving the troubleshooting efficiency of the maintainers, and simultaneously, when a plurality of groups of main office fans 26 and standby office fans 27 need to be powered on to work, the contactor 24 on the overhauling circuit 2 can be connected in series with the main office fan 26 and the standby office fan 27 in the connection mode of the overhauling circuit 2 (such as the above-mentioned above (for example, the standby office fan 27 is connected in series with the contactor 24 and the main office fan 26 and the standby fan 27 can be powered on the connection mode As shown in fig. 2) to effect installation of multiple sets of main office fans 26 and standby office fans 27.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.
Claims (9)
1. The utility model provides a device is transfinited to local fan guarantee technique gas, its characterized in that: the wind-driven switch comprises a wind-driven switch and a detection circuit, wherein a first wiring port and a second wiring port are led out of a control loop of the wind-driven switch;
the detection circuit comprises a main office switch, a relay, a standby office switch, a contactor and a gas substation relay, wherein the main office switch and the standby office switch are connected with the second wiring port in series, the relay, the standby office switch, the contactor and the gas substation relay are sequentially connected in series, the main office switch is connected with the contactor and the gas substation relay in series, the main office switch is connected with the relay and the standby office switch in parallel, and the gas substation relay is connected with the first wiring port in series;
the use method of the device for preventing the gas from exceeding the limit by the local ventilator guarantee technology comprises the following steps:
s1: when the relay does not attract the latching air coupling switch to be powered on, whether a power supply is normally connected or not is checked, no voltage is input into the local fan, and the local fan cannot normally operate;
s2: checking that the isolating switch is not normally opened to cause no voltage input of the spare office fan, so that the spare office fan cannot normally run;
s3: checking whether the fuse tube is fused or not or the contact is poor, so that the voltage cannot be normally input into the spare fan, and the spare fan cannot normally run;
s4: checking whether a spare fan motor protector is damaged or not to cause open circuit, so that the relay can not be normally attracted when the power is cut off;
s5: checking whether a coil in the relay is burnt out or not, so that the relay cannot be normally attracted when being electrified;
s6: and checking whether the insulativity of a motor for driving the spare fan is low or not, so that a coil in the motor is short-circuited, and the relay cannot be normally electrified and closed.
2. The device for preventing the over-limit of the gas in the local ventilator safeguard technology according to claim 1, is characterized in that: the relay is an alternating current relay.
3. The device for preventing the over-limit of the gas in the local ventilator safeguard technology according to claim 1, is characterized in that: the main office switch and the standby office switch are both time relays, and the on-off time periods of the main office switch and the standby office switch are opposite.
4. The device for preventing the over-limit of the gas in the local ventilator safeguard technology according to claim 1, is characterized in that: detection circuitry still includes main office fan and is equipped with the office fan, main office fan series connection in main office switch with between the contactor, be equipped with office fan series connection in be equipped with the office switch with between the contactor, main office fan with be equipped with office fan parallel connection.
5. The device for preventing the over-limit of the gas in the local ventilator safeguard technology according to claim 4, is characterized in that: the drive motor of main office fan and reserve office fan all fixed mounting have JDG motor integrated protection ware.
6. The device for preventing the over-limit of the gas in the local ventilator safeguard technology according to claim 1, is characterized in that: the contactor is a vacuum alternating current contactor.
7. The device for preventing the over-limit of the gas in the local ventilator safeguard technology according to claim 1, is characterized in that: the wind joint switch adopts a QBZ-120SF switch.
8. The device for preventing the over-limit of the gas in the local ventilator safeguard technology according to claim 1, is characterized in that: the main office switch is connected with a manual switch and a standby time relay in parallel, and the manual switch is connected with the standby time relay in series.
9. The apparatus for preventing the over-limit of the gas by the local ventilator safeguard technology as claimed in claim 8, wherein: the on-off time period of the standby time relay is opposite to the on-off time period of the main office switch.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910230732.2A CN110130967B (en) | 2019-03-26 | 2019-03-26 | Device and method for preventing gas from exceeding limit by local ventilator guarantee technology |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910230732.2A CN110130967B (en) | 2019-03-26 | 2019-03-26 | Device and method for preventing gas from exceeding limit by local ventilator guarantee technology |
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| CN110130967A CN110130967A (en) | 2019-08-16 |
| CN110130967B true CN110130967B (en) | 2021-07-30 |
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| CN201910230732.2A Active CN110130967B (en) | 2019-03-26 | 2019-03-26 | Device and method for preventing gas from exceeding limit by local ventilator guarantee technology |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110608184A (en) * | 2019-09-04 | 2019-12-24 | 淮南矿业(集团)有限责任公司 | Locking device for local fan supply of coal mine gas |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN201018259Y (en) * | 2007-03-16 | 2008-02-06 | 王君超 | Protective equipment of contactor for preventing instant power-off |
| CN202301119U (en) * | 2011-09-30 | 2012-07-04 | 永城煤电控股集团有限公司 | Three-fan three-power-supply combination switch for mine local fan |
| CN103711520B (en) * | 2013-12-17 | 2016-12-07 | 国投新集能源股份有限公司 | Underground Local Fan electric power system |
| CN103914061B (en) * | 2014-03-21 | 2016-06-01 | 鞍钢集团矿业公司 | The automatic detection of performer internal fault and shut-off device |
| CN107757084A (en) * | 2016-08-22 | 2018-03-06 | 常州萱娜电子科技有限公司 | High-density interconnected circuit board is with the screen printer counted automatically |
| CN108180156A (en) * | 2016-12-08 | 2018-06-19 | 镇江东正精工机械有限公司 | A kind of high voltage power distributing cabinet auxiliary heat dissipation wind turbine Temperature-control Monitoring device |
| CN206647123U (en) * | 2017-04-24 | 2017-11-17 | 山西汾河焦煤股份有限公司回坡底煤矿 | Mine fan automatic switching control equipment |
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