CN112097399A - Control method for preventing gas water heater from deflagration and gas water heater - Google Patents
Control method for preventing gas water heater from deflagration and gas water heater Download PDFInfo
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- CN112097399A CN112097399A CN201910527906.1A CN201910527906A CN112097399A CN 112097399 A CN112097399 A CN 112097399A CN 201910527906 A CN201910527906 A CN 201910527906A CN 112097399 A CN112097399 A CN 112097399A
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- gas
- water heater
- air
- concentration
- detection device
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 74
- 238000000034 method Methods 0.000 title claims abstract description 39
- 238000004200 deflagration Methods 0.000 title abstract description 7
- 238000001514 detection method Methods 0.000 claims abstract description 61
- 238000002485 combustion reaction Methods 0.000 claims abstract description 30
- 238000005474 detonation Methods 0.000 claims description 7
- 238000006073 displacement reaction Methods 0.000 claims description 3
- 230000005540 biological transmission Effects 0.000 claims description 2
- 239000007789 gas Substances 0.000 abstract description 86
- 239000002737 fuel gas Substances 0.000 abstract description 9
- 239000000779 smoke Substances 0.000 abstract description 9
- 238000004880 explosion Methods 0.000 abstract description 2
- 238000007599 discharging Methods 0.000 description 4
- 239000003517 fume Substances 0.000 description 4
- 238000010586 diagram Methods 0.000 description 2
- 230000002159 abnormal effect Effects 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 235000019504 cigarettes Nutrition 0.000 description 1
- 239000008358 core component Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
- F24H9/00—Details
- F24H9/20—Arrangement or mounting of control or safety devices
- F24H9/2007—Arrangement or mounting of control or safety devices for water heaters
- F24H9/2035—Arrangement or mounting of control or safety devices for water heaters using fluid fuel
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23N—REGULATING OR CONTROLLING COMBUSTION
- F23N1/00—Regulating fuel supply
- F23N1/02—Regulating fuel supply conjointly with air supply
- F23N1/025—Regulating fuel supply conjointly with air supply using electrical or electromechanical means
Abstract
The invention discloses a control method for preventing a gas water heater from deflagration, which comprises the steps of detecting the mixed concentration of current air and gas in a combustion cavity of the water heater by using a concentration detection device, judging the magnitude relation between the mixed concentration of the current air and the gas and a preset standard value, feeding a signal back to a controller by using the concentration detection device when the detected value of the mixed concentration of the current air and the gas is greater than the preset standard value, adjusting the air volume of a fan by using the controller according to the signal, and adjusting the opening degree of a proportional valve to ensure that the mixed concentration of the current air and the gas is the same as the preset standard value, and enabling the gas water heater to enter a normal mode control state. According to the invention, the concentration detection device is adopted to detect the current mixed concentration of air and fuel gas, and the detection signal is fed back to the controller, and the controller performs a process of re-allocating the air quantity of the fan and the opening degree of the proportional valve according to the signal, so that the problem that explosion is easily generated when the smoke discharge resistance is large due to the external environment is effectively prevented.
Description
Technical Field
The invention belongs to the technical field of gas water heaters, and particularly relates to a control method for preventing a gas water heater from deflagrating and the gas water heater.
Background
The gas heater who sells in the existing market, ignition operation when the resistance of discharging fume is great (the great fire of external wind pressure system of discharging fume takes place local jam), produce the abnormal sound of deflagration easily to user's use experience has seriously been influenced.
The noise generated by the water heater is always a key factor influencing the use experience of users, and the source of the noise of the water heater mainly comprises the following points: 1) noise generated during normal combustion; 2) noise generated by an exhaust device and a waterway system; 3) noise generated during ignition operation; 4) the noise generated by repeated ignition caused by unsuccessful ignition; most of the water heaters are determined by the noise of the system structure in the work, and the water heaters belong to the inherent noise of the system; noise generated by the external environment is accidental noise; the former can be solved only by optimizing a combustion system generally, and the noise generated by the latter can be sporadic even after the system is optimized, but the influence of the sporadic factor on the experience of a user in the using process is very serious, the noise generated by normal combustion is generally about 63dB, and the noise generated by deflagration can reach more than 70 dB; the noise generated by the latter can be optimized through a control method, at present, the corresponding ignition load is mainly adjusted by changing the ignition current, and the corresponding air intake is matched, but the problem is only avoided at the front end in the mode, and the problem in the actual use environment cannot be effectively solved.
Disclosure of Invention
In view of the above, the present invention provides a control method for preventing a gas water heater from knocking, which solves the problems of high noise and easy knocking generation in the prior art when smoke discharge resistance is large due to external environment; the invention also aims to provide a gas water heater comprising the control method.
The technical scheme adopted by the invention is as follows: a control method for preventing the explosion of a gas water heater, wherein the gas water heater comprises a concentration detection device for detecting the current mixed concentration of air and gas in a combustion cavity of the gas water heater, and the method comprises the following steps:
the method comprises the steps that the concentration detection device is used for detecting the mixed concentration of current air and gas in a combustion cavity of the water heater, the size relation between the detection value of the mixed concentration of the current air and the gas and a preset standard value is judged, when the detection value of the mixed concentration of the current air and the gas is larger than the preset standard value, the concentration detection device feeds a signal back to a controller, the controller adjusts the air quantity of a fan and the opening of a proportional valve according to the signal, the mixed concentration of the current air and the gas is the same as the preset standard value, and the gas water heater enters a normal mode control state.
Preferably, the specific method is as follows: the method comprises the steps that a concentration detection device is used for detecting the current mixed concentration of air and gas in a combustion cavity of the water heater, the size relation between a detection value of the current mixed concentration of the air and the gas and a preset standard value is judged, when the detection value of the current mixed concentration of the air and the gas is larger than the preset standard value, the concentration detection device converts a signal into an electric signal and feeds the electric signal back to a controller, when the gas water heater is in a working state, the controller adjusts the rotating speed of a fan to be larger and the current of a proportional valve to be smaller according to the electric signal, so that the current mixed concentration of the air and the gas is the same as the preset standard value, and the gas water heater enters a normal mode control state.
Preferably, the method further comprises: when the concentration detection device judges that the detection value of the mixed concentration of the current air and the gas is smaller than or equal to a preset standard value, the controller does not execute a blending program on the air quantity of the fan and the opening degree of the proportional valve, and the gas water heater operates in a normal control mode.
Preferably, the air volume of the fan is in direct proportion to the rotating speed of the fan, and the corresponding relationship between the air volume of the fan and the rotating speed of the fan is as follows:
Q＝V*F＝0.16*b**n*d2*sinψ
wherein V is the wind speed of the outlet of the fan; f is the area of the outlet channel of the fan; d is the diameter of the impeller; b is the volute thickness; n is the impeller rotation speed; is the blade displacement coefficient; psi is the blade operating angle.
The other technical scheme of the invention is realized as follows: the utility model provides a gas water heater, its includes water heater body, concentration detection device, proportional valve and controller, concentration detection device sets up the mixed concentration that is used for detecting air and gas on the water heater body, proportional valve, controller all set up at the water heater originally internally, just the controller is connected the air input that is used for transmission signal and control water heater with concentration detection device, proportional valve respectively.
Preferably, a gas sensor is arranged in the concentration detection device, and the gas sensor is arranged at an exhaust air duct in the combustion cavity of the water heater.
Compared with the prior art, when the device is used, the concentration detection device is adopted to detect the mixed concentration of the current air and the fuel gas in the combustion cavity, the detection signal is fed back to the controller, and the controller performs a process of re-allocating the air quantity of the fan and the opening degree of the proportional valve according to the signal, so that the phenomenon that a large amount of combustible gas cannot be accumulated in the combustion cavity when smoke discharge resistance is large due to the external environment or after repeated ignition is performed for many times is effectively prevented, and the problems of high noise and easiness in detonation are solved.
Drawings
Fig. 1 is a flowchart of a control method for preventing a gas water heater from knocking according to embodiment 1 of the present invention;
FIG. 2 is a comparison graph of the ignition point in the control method for preventing the gas water heater from knocking and the ignition point in the normal mode according to the embodiment 1 provided by the invention;
fig. 3 is a schematic structural diagram of a gas water heater according to embodiment 2 of the present invention.
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.
As shown in fig. 1, the gas water heater includes a concentration detection device for detecting a current mixed concentration of air and gas in a combustion chamber of the gas water heater, and the method includes:
the method comprises the steps that the concentration detection device is used for detecting the mixed concentration of current air and gas in a combustion cavity of the water heater, the size relation between the detection value of the mixed concentration of the current air and the gas and a preset standard value is judged, when the detection value of the mixed concentration of the current air and the gas is larger than the preset standard value, the concentration detection device feeds a signal back to a controller, the controller adjusts the air quantity of a fan and the opening of a proportional valve according to the signal, the mixed concentration of the current air and the gas is the same as the preset standard value, and the gas water heater enters a normal mode control state.
After adopting above-mentioned scheme, during the use, detect the mixed concentration of current air and gas in to the combustion chamber through adopting concentration detection device, and feed back this detected signal to the controller, the process of allotting is carried out again to fan amount of wind and proportional valve opening according to this signal to the controller again, effectual prevent when external environment leads to the resistance of discharging fume when great or after lighting a fire many times repeatedly, can not gather a large amount of combustible gas in the combustion chamber, thereby avoided the big and easy problem that produces deflagration of noise.
Further, the specific method comprises the following steps: the method comprises the steps that a concentration detection device is used for detecting the current mixed concentration of air and fuel gas in a combustion cavity of a water heater, the size relation between a detection value of the current mixed concentration of the air and the fuel gas and a preset standard value is judged, when the detection value of the current mixed concentration of the air and the fuel gas is larger than the preset standard value, the concentration detection device converts a signal into an electric signal and feeds the electric signal back to a controller, when the gas water heater is in a working state (namely a flame signal exists), the controller adjusts the rotating speed of a fan and the current of a proportional valve to be small according to the electric signal, so that the current mixed concentration of the air and the fuel gas is the same as the preset standard value, and the gas water heater enters a normal; when the gas water heater is in a non-working state (namely no flame signal), the controller does not execute a blending program on the air quantity of the fan and the opening degree of the proportional valve, and the gas water heater enters a normal mode control state.
After adopting above-mentioned scheme, during the use, detect the mixed concentration of current air and gas in the combustion chamber through adopting concentration detection device, and judge the big or small relation between the detected value of the mixed concentration of current air and gas and the predetermined standard value, when the detected value of the mixed concentration of current air and gas is greater than the predetermined standard value, concentration detection device converts this signal into the signal of telecommunication and feeds back to the controller, the process of fan rotational speed and the turn down proportional valve electric current is increaseed according to this signal of telecommunication again to the controller, effectually prevented when external environment leads to the resistance of discharging fume great or after many times repeatedly ignitions, can not gather a large amount of combustible gas in the combustion chamber, thereby avoided the big and easy problem that produces the detonation of noise.
Further, the method further comprises: when the concentration detection device judges that the detection value of the mixed concentration of the current air and the gas is smaller than or equal to a preset standard value, the controller does not execute a blending program on the air quantity of the fan and the opening of the proportional valve, and the gas water heater operates in a normal control mode.
Further, the air volume of the fan is in direct proportion to the rotating speed of the fan, and the corresponding relation between the air volume and the rotating speed of the fan is as follows:
Q＝V*F＝0.16*b**n*d2*sinψ
wherein V is the wind speed of the outlet of the fan; f is the area of the outlet channel of the fan; d is the diameter of the impeller; b is the volute thickness; n is the impeller rotation speed; is the blade displacement coefficient; psi is the blade operating angle.
The principle of the control method for preventing the gas water heater from exploding provided by the embodiment 1 of the invention is as follows:
the core component of the concentration detection device is a built-in gas sensor, firstly, the gas sensor is initialized and a preset standard value of the mixed concentration of air and gas is set, secondly, the gas sensor detects the current mixed concentration of the air and the gas (namely the concentration of combustible gas) at the smoke exhaust position in the combustion cavity of the water heater and judges whether the detected value of the mixed concentration of the air and the gas is larger than the preset standard value or not, if so, the concentration detection device converts the signal into an electric signal and feeds the electric signal back to the controller, and the controller adjusts the current of the proportional valve according to the rotation speed of the air blower to enable the current mixed concentration of the air and the gas to be the same as the preset standard value; the magnitude of the electric signal is related to the mixed concentration of air and fuel gas, and the higher the concentration is, the stronger the electric signal is generated.
The control method for preventing the gas water heater from knocking provided by the embodiment 1 of the invention specifically comprises the following steps (as shown in fig. 1):
and (3) a normal control mode: when the external condition and the using environment condition of the whole machine are normal, the control is carried out according to the preset proportion of the current of the fan and the current of the proportional valve, namely: and if the detection value of the current mixed concentration of the air and the gas is smaller than or equal to a preset standard value, the controller does not execute a blending program on the air quantity of the fan and the opening of the proportional valve, and the gas water heater operates in a normal control mode.
Ignition control mode when stifled cigarette: when the ignition operation is carried out in a smoke blocking or wind pressure resistant state, the concentration detection device detects the concentration of instantaneous gas (namely mixed gas of air and fuel gas) in the combustion cavity in real time, and compares the detected value of the gas concentration with a preset standard value, when the detected value of the gas concentration is larger than the preset standard value, the concentration detection device converts the signal into an electric signal and feeds the electric signal back to the controller, and the controller reconfigures the rotating speed of a fan and the current of a proportional valve during ignition so as to reduce the concentration of combustible gas in the combustion cavity; after the ignition is successful, the normal control mode is recovered for control; at this moment, if the rotating speed of the fan and the current of the proportional valve are not reconfigured according to the prior art, a large amount of combustible gas is possibly accumulated in the combustion cavity during smoke blockage or after repeated ignition, the concentration is high, and then, the successful ignition can generate a very large detonation sound, so that the use experience is seriously influenced.
In addition, in an ignition control mode during smoke blockage, as the internal pressure of the combustion cavity rises, the exhaust resistance is increased, the volume of gas in the cavity is compressed, and the concentration rises; the air volume F of the fan is improved, the load value of DH is reduced, the concentration of combustible gas in the cavity is reduced, deflagration is slowed down under the condition that ignition is successful, the combustor is switched to be operated in a normal mode state after being ignited, the specific schematic diagram is shown in figure 2, and accordingly accidental noise generated in the use process of the gas water heater can be effectively solved.
The gas water heater provided by the embodiment 2 of the invention comprises a water heater body, a concentration detection device, a proportional valve and a controller, as shown in fig. 3, wherein the concentration detection device is arranged on the water heater body and used for detecting the mixed concentration of air and gas, the proportional valve and the controller are both arranged in the water heater body, and the controller is respectively connected with the concentration detection device and the proportional valve and used for transmitting signals and controlling the air inflow of the water heater.
By applying the control method in embodiment 1 of the present invention to the gas water heater in embodiment 2 of the present invention, it is effectively prevented that a large amount of combustible gas is not accumulated in the combustion chamber when the smoke discharge resistance is large due to the external environment or after repeated ignition, so that the problems of high noise and easy detonation are avoided.
Further, a gas sensor is arranged in the concentration detection device and is arranged at an air exhaust duct in the combustion cavity of the water heater.
After the control method provided by the embodiment of the invention is adopted, when the concentration detection device is used, the concentration detection device is adopted to detect the current mixed concentration of the air and the fuel gas in the combustion cavity, the detection signal is fed back to the controller, and the controller performs a re-allocation process on the air quantity of the fan and the opening degree of the proportional valve according to the signal, so that the phenomenon that a large amount of combustible gas is not accumulated in the combustion cavity when the smoke discharge resistance is large due to the external environment or after repeated ignition is carried out for many times is effectively prevented, and the problems of high noise and easiness in detonation are avoided.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (6)
1. A control method for preventing the gas water heater from knocking is characterized in that the gas water heater comprises a concentration detection device for detecting the current mixed concentration of air and gas in a combustion cavity of the gas water heater, and the method comprises the following steps:
the method comprises the steps that the concentration detection device is used for detecting the mixed concentration of current air and gas in a combustion cavity of the water heater, the size relation between the detection value of the mixed concentration of the current air and the gas and a preset standard value is judged, when the detection value of the mixed concentration of the current air and the gas is larger than the preset standard value, the concentration detection device feeds a signal back to a controller, the controller adjusts the air quantity of a fan and the opening of a proportional valve according to the signal, the mixed concentration of the current air and the gas is the same as the preset standard value, and the gas water heater enters a normal mode control state.
2. The control method for preventing the detonation of the gas water heater according to claim 2, characterized in that the specific method is as follows: the method comprises the steps that a concentration detection device is used for detecting the current mixed concentration of air and gas in a combustion cavity of the water heater, the size relation between a detection value of the current mixed concentration of the air and the gas and a preset standard value is judged, when the detection value of the current mixed concentration of the air and the gas is larger than the preset standard value, the concentration detection device converts a signal into an electric signal and feeds the electric signal back to a controller, the controller adjusts the rotating speed of a fan to be larger and adjusts the current of a proportional valve to be smaller according to the electric signal, the current mixed concentration of the air and the gas is the same as the preset standard value, and the gas water heater enters a normal mode control state.
3. A control method for preventing knocking of a gas water heater according to claim 1 or 2, further comprising: when the concentration detection device judges that the detection value of the mixed concentration of the current air and the gas is smaller than or equal to a preset standard value, the controller does not execute a blending program on the air quantity of the fan and the opening degree of the proportional valve, and the gas water heater operates in a normal control mode.
4. The control method for preventing the detonation of the gas water heater according to claim 3, wherein the air volume of the fan is in direct proportion to the rotating speed of the fan, and the corresponding relationship between the air volume of the fan and the rotating speed of the fan is as follows:
Q＝V*F＝0.16*b**n*d2*sinψ
wherein V is the wind speed of the outlet of the fan; f is the area of the outlet channel of the fan; d is the diameter of the impeller; b is the volute thickness; n is the impeller rotation speed; is the blade displacement coefficient; psi is the blade operating angle.
5. The utility model provides a gas water heater, its characterized in that, it includes water heater body, concentration detection device, proportional valve and controller, concentration detection device sets up the mixed concentration who is used for detecting air and gas on the water heater body, proportional valve, controller all set up at the water heater originally internally, just the controller is connected the air input that is used for transmission signal and control water heater with concentration detection device, proportional valve respectively.
6. The gas water heater of claim 5, wherein a gas sensor is disposed in the concentration detecting device, and the gas sensor is disposed at an exhaust duct in the combustion chamber of the water heater.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910527906.1A CN112097399A (en) | 2019-06-18 | 2019-06-18 | Control method for preventing gas water heater from deflagration and gas water heater |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910527906.1A CN112097399A (en) | 2019-06-18 | 2019-06-18 | Control method for preventing gas water heater from deflagration and gas water heater |
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| Publication Number | Publication Date |
|---|---|
| CN112097399A true CN112097399A (en) | 2020-12-18 |
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|---|---|---|---|
| CN201910527906.1A Pending CN112097399A (en) | 2019-06-18 | 2019-06-18 | Control method for preventing gas water heater from deflagration and gas water heater |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE60229381D1 (en) * | 2001-05-11 | 2008-11-27 | New Power Concepts Llc | SYSTEM AND METHOD FOR THE SENSOR CONTROL OF THE FUEL / AIR CONDITION IN A BURNER |
| CN205842663U (en) * | 2016-06-17 | 2016-12-28 | 金奇能（北京）厨房设备有限公司 | Energy-saving kitchen range stove |
| CN107894012A (en) * | 2017-10-26 | 2018-04-10 | 广东美的厨房电器制造有限公司 | The control method of gas-cooker and gas-cooker |
-
2019
- 2019-06-18 CN CN201910527906.1A patent/CN112097399A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE60229381D1 (en) * | 2001-05-11 | 2008-11-27 | New Power Concepts Llc | SYSTEM AND METHOD FOR THE SENSOR CONTROL OF THE FUEL / AIR CONDITION IN A BURNER |
| CN205842663U (en) * | 2016-06-17 | 2016-12-28 | 金奇能（北京）厨房设备有限公司 | Energy-saving kitchen range stove |
| CN107894012A (en) * | 2017-10-26 | 2018-04-10 | 广东美的厨房电器制造有限公司 | The control method of gas-cooker and gas-cooker |
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Application publication date: 20201218 |