CN1332152C - Air proportional boiler using air pressure sensor - Google Patents
Air proportional boiler using air pressure sensor Download PDFInfo
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- CN1332152C CN1332152C CNB031101291A CN03110129A CN1332152C CN 1332152 C CN1332152 C CN 1332152C CN B031101291 A CNB031101291 A CN B031101291A CN 03110129 A CN03110129 A CN 03110129A CN 1332152 C CN1332152 C CN 1332152C
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Abstract
The present invention provides an air-proportional type boiler which uses an air pressure sensor. When an air pressure sensor which proportionally detects air quantity through a pressure difference is utilized to control a combustion gas supply quantity so as to make the combustion gas supply quantity is in a certain proportion to a sucked air supply quantity, if the air supply quantity is reduced, the supply quantity of the combustion gas is reduced, and the boiler output is reduced. When the supply quantity of the combustion gas is fixed to generate constant rated output, the rotation number of a blower is adjusted to keep the air supply quantity constant. Therefore, the air is proportionally supplied according to the supply quantity of the combustion gas at all times. Because the combustion gas and the air are supplied according to the desired quantity of the rated output of the boiler at all times, the combustion efficiency is enhanced, harmful exhaust gas is farthest reduced, and the environmental pollution is prevented in advance.
Description
Technical field
The present invention relates to a kind of AIR Proportional formula boiler that uses air pressure probe, more particularly, relating to a kind of air pressure probe that utilizes makes boiler keep the AIR Proportional formula boiler of specified output, wherein reasonably regulate the revolution of air blast, so that it is constant and when producing constant specified output in the gas supply amount, make wind supply quantity keep constant, so just can solve following problems: when utilizing air pressure probe and pressure reduction to detect air capacity in proportion, air demand with the control combustion gas, when making itself and the wind supply quantity that sucks proportional, if wind supply quantity reduces, the air demand of combustion gas is also reduced, thereby cause the output quantity of boiler to reduce.
Background technology
The boiler that is used for heat supply and provides hot water to general family is divided into oil burning boiler and gas fired-boiler according to the fuel that uses.Because gas fired-boiler is less to the pollution of atmosphere, and easy to use, so this boiler of main at present employing.This boiler acts as a fuel with liquefied natural gas (LNG).
Gas fired-boiler can be divided into condensing and on-condensing according to the heat exchanger of heat cycles water.The heat of condensation gas fired-boiler utilization burning is heat cycles water directly, and with the condensation latent heat in the recovery waste gas, thereby improved the thermal efficiency to the maximum limit.
Conventional condensation gas boiler will be described below.In the condensation gas boiler of routine, a burner is installed in the top of boiler, so just can light the combustion gas that mixes with air, and burning downwards.Be installed in the heat exchanger that is used for heating of boiler bottom, utilizing high-temperature fuel gas to add hot fluid or recirculated water.Fluid after the heating or water circulation flow in bedroom, parlor or the bathroom, to carry out heat supply running.
In addition, when hot water moved, the operation triple valve interrupting providing hot water to bedroom, parlor or bathroom, and was transformed into the hot water heat exchanger of installation parallel with one another with valve, with used as thermal source.When recirculated water is admitted to heat exchanger, and when in heat exchanger, regathering the recirculated water of supply, the recirculated water that is used for bathing is heated.
According to control method or sealing state, the gas fired-boiler that constitutes in a manner described can be divided into different types.Particularly, AIR Proportional formula boiler is measured the pressure from outside inhaled air, will offer burner with the proportional fuel of the air pressure of measuring then.Therefore, provide accurate fuel quantity, so just improved efficiency of combustion, and reduced pernicious gas to greatest extent, thereby prevent from air is polluted in ratio with air pressure.
That is to say, because the gas supply amount of regulating only changes with air pressure, therefore under the situation of the proportion control part of not controlling gas trap individually, certain relatively air pressure provides a certain amount of combustion gas, thereby can keep constant air-fuel ratio all the time.Therefore, accurate proportion control operation is different from ON/OFF control type or the operation of proportion of flow formula.
Exercise question was the Korean Patent Publication No. 10-2000-26741 of " AIR Proportional formula condensing boiler ", and the applying date is the korean patent application on May 15th, 2000, licensed to the application's applicant on August 8th, 2000.
Fig. 1 is the topology view of the conventional AIR Proportional formula condensing boiler of expression; Fig. 2 is the block diagram of the conventional AIR Proportional formula condensing boiler of expression.
At first, as shown in Figure 1, utilize AIR Proportional formula method operation condensation gas boiler, thereby constant air capacity can be provided all the time according to the temperature conditioned air pressure of outside atmosphere.Condensation gas boiler comprises: a seal 2, and it has the air intake pipe 3 and the exhaust emission tube 20 that is used for to the outside drain burnt gas that are used for sucking according to the operation of air blast 10 extraneous air; A combustion chamber 4, it has a burner 12, and this burner is used to burn through first and second motor-driven valves 46 and 46 ' and combustion gas of providing of AIR Proportional valve 47 and mixture by air blast 10 inhaled airs; Sensible heat exchanger 14 that is used for heat cycles water and one is all-in-one-piece latent heat exchanger 16 with it; A hot water heat exchanger 34, it is used to utilize the heat recirculated water heating by sensible heat exchanger 14 to supply water; A water circulating pump 22, the recirculated water that it is used for flowing through circulating water strainer 24 and air/water separator 26 offers latent heat exchanger 16; And an expansion tank 48, it is used to store the part recirculated water of importing according to the operation of triple valve 28 and anti-excess pressure valve 32.
In addition, air pressure sensor 50 is installed for air-ratio, and it is installed in the suction muffler 6, is used to detect the air pressure by air blast 10 inhaled airs.If the pressure identifier 51 in air-proportioning valve 47 identifies air pressure, then controller 40 bases are by the combustion chamber 4 in the pneumatics identifier 51 detected air-pressure controlling boilers, to spray the combustion mode of combustion gas.In addition, controller 40 receives the signal of temperature sensors, and according to the signal of temperature sensor, the data of utilizing the current temperature of expression whether to reach design temperature are calculated thermal capacity.Controller 40 also carries out power-control to the revolution of air blast 10, and changes air pressure according to its required revolution, regulating the combustion gas discharge rate of air-proportioning valve 47, thereby and regulates the gas supply amount that offers burner 12.
In more detail, burner 12 is installed in the top of combustion chamber 4, and it is according to the operation combustion gas of air blast 12 and mixture through suction muffler 6 inhaled airs.Sensible heat exchanger 14 and latent heat exchanger 16 are successively set on the below of burner 12.In running, sensible heat exchanger 14 heat cycles water, wherein the sensible heat of burner generation directly contacts with recirculated water.Latent heat exchanger 16 is utilized the latent heat heat cycles water that produces when contacting with waste gas heat.
Waste gas by latent heat exchanger 16 is discharged into the outside by flue gas leading 20, and the condensed water that produces when heat exchange is collected in the exhaust hood 18, and then is discharged into the outside.According to the operation of water circulating pump 22, recirculated water is heated successively by latent heat exchanger 16 and sensible heat exchanger 14 time.Utilize thermistor 52 to detect the temperature of the recirculated water after heating, send detected temperature to controller 40 then.
The water circulating pump 22 that is used to recirculated water is circulated is arranged on the lower left quarter of boiler.When water circulating pump 22 operation, finished to the recirculated water of indoor heating by the road L1 be sent to circulating water strainer 24.Circulating water strainer 24 is removed contained impurity in the recirculated water.Recirculated water is transported to the air/water separator 26 that is positioned at the circulating water strainer top.Air/water separator 26 emits the air in the recirculated water through last air scoop.
Be used to prevent that the anti-excess pressure valve 32 that circulating water pressure rises so high is installed between circulating water strainer 24 and the air/water separator 26, this valve is transported to expansion tank 48 with part recirculated water, thereby has regulated pressure.By the operation of water circulating pump 22, recirculated water that will be by air/water separator 24 L2 by the road is transported to latent heat exchanger 16, by sensible heat exchanger 14 time it is heated then, and L3 discharges it by the road again.According to the operation of triple valve 28, the recirculated water by pipeline L3 is transported to indoor.
The heat exchanger that utilizes the heat of recirculated water to produce hot water is arranged on the middle and lower part of boiler.According to the operation of hot water flow switch 36, the cold water of importing by pipeline L6 is heated in the process by hot water heat exchanger 34, then by pipeline L7 discharging.Hot water heat exchanger 34 of the present invention has parallel type structure, and sets less deviation range, therefore compared with prior art can control to very little zone.So just enlarge the workspace of boiler, thereby reduced harmful exhaust to greatest extent.
The burning feedway is installed in the right lower quadrant of boiler.According to first and second motor-driven valves 46 and 46 ' and the output signal of the air blast 10 that transmits of slave controller 40 revolution of air blast 10 is carried out power control.Simultaneously, according to the operation of the air-proportioning valve 47 that can change the gas emission amount, combustion gas that will be by pipeline L8 input L9 by the road offers the nozzle 8 that is positioned at 4 tops, combustion chamber.Here, the gas supply amount changes according to the operation of air-proportioning valve 47.Therefore, the additional variation that will depend on extraneous air of gas supply amount.Utilization is lighted the combustion gas that provides by this method by the spark of ignition transformer 42 and spark lever transmission and is burnt.Above-mentioned combustion process is by controller 40 controls, and this controller 40 is controlled by the input signal that receives the indoor temperature adjuster of being handled by the user 38.
The running of air-proportion expression condensing boiler is described with reference to Fig. 2 below.
As mentioned above, utilize the air-proportion expression boiler of air pressure to calculate heat, the revolution to air blast 10 carries out power control then, thereby changes air pressure according to required revolution.Therefore, regulate the gas emission amount of air-proportioning valve 47 according to the change of air pressure, thereby can regulate the gas supply amount that will offer burner 12.
An ON/OFF control formula pneumatics switch and an air-proportion expression pneumatics switch as pneumatics detector 50 are provided here.After detecting air pressure, ON/OFF control formula pneumatics switch will pass to diaphragm by the air pressure of air blast input, and make the microswitch that is connected on the diaphragm can be switched on or switched off circuit.Air-proportion expression pneumatics switch is when the reducing of the blow rate required, and the signal that the indication blow rate required is reduced sends the air-proportioning valve in the Gas Pipe to, and reduces the supply of combustion gas in proportion.
Because ON/OFF control formula pneumatics switch uses fixing operating pressure, so should adopt specific pneumatics switch according to air blast.In addition, because existing air-proportion expression pneumatics switch is according to regulating the gas supply amount by the air quantity delivered of the input of the air blast in the boiler, so the waste gas passing away may be blocked by foreign substance.Therefore, under the situation that the wind supply quantity of air blast reduces, the gas supply amount that offers boiler also reduces, thereby has reduced the output of boiler.
In addition, pneumatic sensor (AFS) is used on the automobile as pneumatics detector 50.If foreign substance is deposited on the surface of sensor, then sensitiveness can reduce.If the air themperature of measuring changes, then when measuring flow, can produce error.In addition, pneumatic sensor (AFS) is more expensive than existing pneumatics sensor.
Summary of the invention
In order to address the above problem, the purpose of this invention is to provide a kind of air-proportion expression boiler, it uses a pneumatics sensor, be used to keep the specified output of boiler, wherein, constant in the gas supply amount, thereby when forming constant specified output, revolution to air blast is regulated, so that wind supply quantity is constant, so just can utilize the pneumatics sensor and the pressure reduction control gas supply amount that detect air capacity in proportion, the wind supply quantity that makes it and suck is proportional, the gas supply amount also reduces when wind supply quantity reduces to solve, thus the problem that causes the output of boiler to reduce.
In order to realize above-mentioned purpose of the present invention, a kind of air-proportion expression boiler that uses the pneumatics sensor is set, it can regulate the fuel quantity that will provide by the certain proportion that sucks air, and this air, proportion expression boiler comprise: an air blast, and it is used for sucking air by air intake pipe; A pneumatics detector, it is installed in the suction muffler, is used for measuring by air blast inhaled air pressure; A pneumatics identifier, it is used for the air pressure by the pneumatics detectors measure is converted to the signal of telecommunication and exports this signal of telecommunication; A fuel control motor-driven valve, it is used to regulate the fuel quantity that will supply with; And controller, it is used for according to the air pressure fuel metering control motor-driven valve from the input of pneumatics identifier, to control the fuel quantity that to supply with, and after definite fuel quantity, supply with the suction air period that adapts with the fuel quantity of determining, under the situation that inhaled air pressure changes, the revolution of regulating air blast is so that the suction constant amount of air of supplying with, thereby keeps the specified output of boiler.
Various details is used the function of the air-proportion expression boiler of pneumatics sensor.
The pneumatics detector detects the pressure of inhaled air by the running of air blast.Controller detects air pressure by the pneumatics identifier, and operation fuel control motor-driven valve, provides fuel by the certain proportion with air capacity, thereby makes boiler operatiopn.In addition, when constant fuel feed is provided for the specified output that keeps boiler, owing to external factor makes under the situation that the pressure that sucks air changes, controller is regulated the revolution of air blast, so that make inhaled air and the fuel that provides keep certain proportion, thereby keep the specified output of boiler.
Description of drawings
After the reference accompanying drawing has described the preferred embodiments of the present invention in detail, above-mentioned purpose of the present invention and other advantage will become more obvious.Wherein:
Fig. 1 is the structure chart of the air-proportion expression condensing boiler of routine;
Fig. 2 is the block diagram of the air-proportion expression condensing boiler of routine;
Fig. 3 is the square frame of the air-proportion expression condensing boiler of use pneumatics sensor of the present invention.
The specific embodiment
Referring now to accompanying drawing a preferred embodiment of the present invention is described.In addition, this embodiment is not the restriction to technical scope of the present invention, and just illustrates.Adopt identical Reference numeral with parts identical in the prior art.
Fig. 3 is the square frame by the air of use pneumatics sensor of the present invention-proportion expression condensing boiler.
As shown in Figure 3, air-proportion expression condensing boiler comprises: a pneumatics detector 50 that is installed in the suction muffler 6, and it is used for measuring by air blast 10 inhaled air pressure; A pneumatics identifier 51, it is used for the air pressure by the pneumatics detectors measure is converted to the signal of telecommunication and exports this signal of telecommunication; A fuel control motor-driven valve 60, it is used to regulate the fuel quantity that will supply with; A thermistor 52, it is used to detect the temperature of recirculated water; An indoor temperature adjuster 38, it handles a series of combustion processes by the user; An ignition transformer 42, the spark that it is used to produce is supplied fuel to light; A water circulating pump 22, it is used to make recirculated water to circulate; First and second motor-driven valves 46 and 46 ', they are used to regulate the fuel quantity that will supply with; And controller 40 ', it not only is used for the temperature of the recirculated water that detects according to thermistor 52 and controls the revolution of air blast 10 from the various input signals of being selected by the user of indoor temperature adjuster 38, and excitation ignition transformer 42, first and second motor-driven valves 46 and 46 ' and water circulating pump 22, and according to air pressure fuel metering control motor-driven valve 60 from 51 inputs of pneumatics identifier, quantity delivered with control fuel, but also be used for the quantity delivered of based on fuel, under the situation that the pressure that sucks air changes, regulate the revolution of air blast, thereby keep the specified output of boiler.
Like this, if the user for heating purposes by indoor temperature adjuster 38 operation boilers, controller 40 ' start water circulating pump 22 and air blast 10 then.Then, pneumatics detector 50 detects the air pressure that caused by pressure reduction and the air pressure that detects is exported to pneumatics identifier 51.Pneumatics identifier 51 is according to the current wind supply quantity that offers the combustion chamber of input signal detection then, and the revolution of control air blast 10, till the wind supply quantity that detects changes to the necessary wind supply quantity of igniting.If wind supply quantity changes to when suitable, then connect ignition transformer 42, and in the constant time, keep the necessary wind supply quantity of igniting.First and second motor-driven valves 46 and 46 ' unlatching then, and only light the necessary fuel of this wind supply quantity.Cut off ignition transformer 42 then, to begin to heat operation.
As mentioned above, controller a 40 ' combusting boiler, detect the temperature of recirculated water by thermistor 52, calculate necessary heat according to the ratio formula, to control the temperature of current recirculated water, make it keep proportional with the temperature of the recirculated water of setting, revolution according to the heat Calculation air blast 10 that calculates, air blast 10 is controlled to revolution running to calculate, according to air pressure from 51 inputs of pneumatics identifier, fuel duty is converted to the required suitable burning supply of burner 12, and according to the fuel duty control fuel control motor-driven valve 60 after changing, with the fuel metering supply.
In addition, if foreign substance has blocked the waste gas passing away, thereby and when exporting specified output, boiler causes reducing of wind supply quantity, if or the measure error that causes owing to the pollution of pneumatics detector 50, or the temperature that sucks air changes, then the fuel duty of Xi Ruing also changes, thereby causes non-specified output.In this case, the revolution of controller 40 ' control air blast 10 makes the wind supply quantity of suction can be proportional with a certain amount of fuel that provides by fuel control motor-driven valve 60, thereby makes the wind supply quantity of suction remain constant.Therefore, owing to always provide fuel and air by the required amount of specified output, thus just improved efficiency of combustion, and reduced harmful exhaust to greatest extent, thus can prevent pollution on the environment in advance.
As mentioned above, the air of use pneumatics sensor of the present invention-proportion expression boiler can be kept the specified output of boiler, wherein working as the gas supply amount fixes, when producing constant specified output, the revolution of air blast is regulated, so that wind supply quantity is constant, so that address the problem: when utilizing the pneumatics sensor control gas supply amount that detects air capacity by pressure reduction in proportion, when proportional, if wind supply quantity reduces, then the gas supply amount also reduces with the wind supply quantity that makes it and suck.Therefore, because gas supply amount and wind supply quantity always provide by the required amount of specified output, thus improved efficiency of combustion, and reduced harmful exhaust to greatest extent, thus pollution on the environment can be prevented in advance.
The invention is not restricted to the foregoing description, obviously, those skilled in the art can carry out many improvement and conversion under the situation that does not break away from spirit of the present invention and claim restricted portion.
Claims (1)
1. air-proportion expression boiler that uses the pneumatics sensor, it can regulate the fuel quantity that will provide by the certain proportion that sucks air, and this air-proportion expression boiler comprises:
An air blast, it is used for sucking air by air intake pipe;
A pneumatics detector, it is installed in the suction muffler, is used for measuring by air blast inhaled air pressure;
A pneumatics identifier, it is used for the air pressure by the pneumatics detectors measure is converted to the signal of telecommunication and exports this signal of telecommunication;
A fuel control motor-driven valve, it is used to regulate the fuel quantity that will supply with; And
A controller, it is used for according to the air pressure fuel metering control motor-driven valve from the input of pneumatics identifier, to control the fuel quantity that to supply with, and after definite fuel quantity, supply with the suction air period that adapts with the fuel quantity of determining, under the situation that inhaled air pressure changes, the revolution of regulating air blast is so that the suction constant amount of air of supplying with, thereby keeps the specified output of boiler.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB031101291A CN1332152C (en) | 2003-04-11 | 2003-04-11 | Air proportional boiler using air pressure sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB031101291A CN1332152C (en) | 2003-04-11 | 2003-04-11 | Air proportional boiler using air pressure sensor |
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| Publication Number | Publication Date |
|---|---|
| CN1536272A CN1536272A (en) | 2004-10-13 |
| CN1332152C true CN1332152C (en) | 2007-08-15 |
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| Application Number | Title | Priority Date | Filing Date |
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| CNB031101291A Expired - Lifetime CN1332152C (en) | 2003-04-11 | 2003-04-11 | Air proportional boiler using air pressure sensor |
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Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4413249B2 (en) * | 2007-07-11 | 2010-02-10 | 太陽築炉工業株式会社 | Cremation furnace combustion control system and cremation furnace combustion control method |
| CN102937382B (en) * | 2012-11-21 | 2015-05-27 | 中冶南方(武汉)威仕工业炉有限公司 | Adjusting and optimizing method of ratio-controlled combustion system |
| CN104713124A (en) * | 2015-04-02 | 2015-06-17 | 桂林市淦隆信息科技有限公司 | Intelligent combustion control system for liquid fuel |
| CN112762984A (en) * | 2020-12-16 | 2021-05-07 | 常州信息职业技术学院 | Automobile electromechanical engineering sensor detection system |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2165347A (en) * | 1984-10-04 | 1986-04-09 | British Gas Corp | Burner air/gas ratio control |
| GB2253927A (en) * | 1991-03-13 | 1992-09-23 | Holland Janet | Improvements in or relating to gas-heated hot water boilers |
| JPH06265139A (en) * | 1993-03-10 | 1994-09-20 | Osaka Gas Co Ltd | Burner |
| EP0909922A1 (en) * | 1997-10-17 | 1999-04-21 | IABER S.p.A. | Combined gas-air control system for controlling combustion in gas fired boilers |
| CN1389680A (en) * | 2000-03-03 | 2003-01-08 | 利雅路股份有限公司 | Air-gas regulating system of boiler |
-
2003
- 2003-04-11 CN CNB031101291A patent/CN1332152C/en not_active Expired - Lifetime
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2165347A (en) * | 1984-10-04 | 1986-04-09 | British Gas Corp | Burner air/gas ratio control |
| GB2253927A (en) * | 1991-03-13 | 1992-09-23 | Holland Janet | Improvements in or relating to gas-heated hot water boilers |
| JPH06265139A (en) * | 1993-03-10 | 1994-09-20 | Osaka Gas Co Ltd | Burner |
| EP0909922A1 (en) * | 1997-10-17 | 1999-04-21 | IABER S.p.A. | Combined gas-air control system for controlling combustion in gas fired boilers |
| CN1389680A (en) * | 2000-03-03 | 2003-01-08 | 利雅路股份有限公司 | Air-gas regulating system of boiler |
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| Publication number | Publication date |
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| CN1536272A (en) | 2004-10-13 |
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Granted publication date: 20070815 |