Combustor and water heater

Abstract

The application discloses a burner and a water heater, wherein the burner comprises a burner body, a first combustion chamber and a second combustion chamber which are sequentially connected, a pre-distribution device arranged on the burner body and used for connecting gas and air to form mixed gas, a preheating combustion device arranged on the burner body and used for connecting the mixed gas input by the pre-distribution device and inputting the mixed gas into the first combustion chamber to perform preheating combustion, a gas injection assembly arranged on the burner body, and a gas supplementing device arranged on the burner body and communicated with the gas injection assembly and used for inputting gas into the gas injection assembly so that the air-fuel ratio of the mixed gas output by the preheating combustion device is not equal to the air-fuel ratio of the mixed gas output by the gas injection assembly. The air-fuel ratio of the gas injection assembly is adjusted, and the air-fuel ratio is adjusted according to the combustion condition.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of water heaters, in particular to a burner and a water heater. BACKGROUND

[0002] When the existing water heater is running, the required gas supply of the water heater is limited by the gas valve, and the supply of gas and air is usually in a constant state. When the water heater switches between different operating states, the required gas amount of the burner is different, and the constant gas supply will affect the combustion efficiency of the gas, part of the gas is not fully combusted, which increases the amount of harmful gases in the flue gas and reduces the effective utilization rate of the gas. SUMMARY

[0003] The main purpose of the present application is to provide a burner and a water heater, which aims to improve the problem of low gas utilization rate caused by unreasonable air-fuel ratio of the existing water heater.

[0004] To achieve the above purpose, the burner provided by the present application comprises:

[0005] A burner body, wherein the burner body is formed with a first combustion chamber and a second combustion chamber connected in sequence;

[0006] A pre-distribution device arranged in the burner body and used for connecting gas and air to form a mixed gas;

[0007] A preheating combustion device arranged in the burner body and used for connecting the mixed gas input by the pre-distribution device and inputting the mixed gas to the first combustion chamber to perform preheating combustion, so as to form high-temperature flue gas transported to the second combustion chamber;

[0008] A gas injection assembly arranged in the burner body and used for connecting the mixed gas input by the pre-distribution device and transporting the mixed gas to the second combustion chamber, so that a high-temperature air combustion reaction is performed in the second combustion chamber; and

[0009] A gas supplementing device arranged in the burner body and in communication with the gas injection assembly, and used for inputting gas to the gas injection assembly, so that the air-fuel ratio of the mixed gas output by the preheating combustion device is not equal to the air-fuel ratio of the mixed gas output by the gas injection assembly.

[0010] Optionally, the pre-distribution device comprises:

[0011] A premixer arranged in the burner body and used for connecting gas and air to form a mixed gas, wherein the preheating combustion device and the gas injection assembly are in communication with the premixer.

[0012] Optionally, the pre-distribution device further comprises:

[0013] A pre-distribution chamber is arranged in the burner body and connected with the premixer, and the preheating combustion device and the gas injection assembly are respectively connected with the premixer through the pre-distribution chamber.

[0014] Optionally, the gas injection assembly comprises:

[0015] A shell is arranged in the burner body, and a gas distribution chamber is formed in the shell, the air supplementing device is connected with the gas distribution chamber, and the shell is connected with the pre-distribution device.

[0016] A nozzle is arranged in the shell and communicates with the gas distribution chamber, and the nozzle is used for injecting gas into the second combustion chamber.

[0017] Optionally, the number of the nozzles is plural, and the plural nozzles are arranged at intervals on the shell.

[0018] Optionally, the gas injection assembly further comprises:

[0019] A connecting assembly is arranged in the burner body and used for connecting the pre-distribution device with the gas distribution chamber.

[0020] Optionally, the connecting assembly comprises:

[0021] A first connecting section is arranged in the burner body, and a first gas flow channel communicating with the pre-distribution device is formed in the first connecting section.

[0022] A second connecting section is arranged in the burner body, and a second gas flow channel is formed in the second connecting section, the first gas flow channel communicates with the gas distribution chamber through the second gas flow channel, and the second connecting section is arranged at intervals with the burner body.

[0023] Optionally, the gas distribution chamber has a first end close to the nozzle and a second end away from the nozzle, and an end of the second gas flow channel away from the first gas flow channel communicates with the second end of the gas distribution chamber.

[0024] Optionally, the burner further comprises:

[0025] A gas valve is arranged in the burner body, the pre-distribution device has an air inlet and a gas inlet, and the gas inlet of the pre-distribution device and the air supplementing device are respectively connected with the gas valve.

[0026] The application further provides a water heater, which comprises:

[0027] A machine body;

[0028] The burner as described above is arranged in the machine body.

[0029] A heat exchanger is located in the machine body and is connected to the second combustion chamber of the burner.

[0030] Optionally, the water heater further includes:

[0031] Temperature sensor for the temperature inside the second combustion chamber; and

[0032] The controller, electrically connected to the body and the temperature sensor, is used to acquire the temperature inside the second combustion chamber and the required heat load of the water heater; and is also used to control the gas injection assembly to inject gas into the second combustion chamber when the temperature inside the second combustion chamber reaches a preset temperature, so that the second combustion chamber performs high-temperature air combustion to achieve the required heat load range of the water heater.

[0033] The technical solution of this invention employs a pre-distribution device to supply a mixture of fuel gas and air to the preheating combustion device and the gas injection assembly, thereby supplying the preheating combustion device with a gas at a preset air-fuel ratio. A supplementary gas or air device is used to supplement the gas injection assembly, adjusting the air-fuel ratio of the gas injection assembly. This results in different air-fuel ratios required for combustion in the first and second combustion chambers, allowing for adjustment of the air-fuel ratio based on the combustion conditions in both chambers. This, in turn, improves the utilization efficiency of the fuel gas and enhances the combustion efficiency of the burner. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0035] Figure 1 This is a schematic diagram of the structure of one embodiment of the burner of the present invention in use;

[0036] Figure 2 for Figure 1 The left view;

[0037] Figure 3 for Figure 1 Sectional view along the middle AA direction;

[0038] Figure 4 This is a schematic diagram of the structure of an embodiment of the gas injection assembly of the present invention;

[0039] Figure 5 This is a schematic diagram of the internal structure of an embodiment of the gas injection assembly of the present invention.

[0040] BRIEF DESCRIPTION OF DRAWINGS

[0041] Reference Name Reference Name 10 Machine body 11 Heat exchanger 12 Heat exchange tube 13 Fume hood 14 Fume exhaust pipe 15 Temperature sensor 20 Pre-distribution device 21 Pre-mixer 22 Gas inlet 23 Air inlet 24 Pre-distribution chamber 30 Pre-heating combustion device 40 Air supplement device 50 Gas injection assembly 51 Housing 52 Gas distribution chamber 53 Nozzle 54 First connecting section 55 First gas flow channel 56 Second connecting section 57 Second gas flow channel 60 Gas valve 61 First control valve 62 Second control valve 70 First combustion chamber 80 Second combustion chamber

[0042] The objectives, features and advantages of the present application will be further illustrated by the following embodiments in conjunction with the accompanying drawings. DETAILED DESCRIPTION

[0043] The technical solutions in the embodiments of the present application will be apparently and completely described with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without any creative work fall within the protection scope of the present application.

[0044] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement condition, etc. between components in a certain posture (as shown in the drawings). If the certain posture changes, the directional indications also change accordingly.

[0045] In addition, if the embodiments of the present application involve descriptions of “first”, “second”, etc., the descriptions of “first”, “second”, etc. are only for description purposes, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited by “first”, “second” can explicitly or implicitly include at least one of the features. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the fact that a person skilled in the art can realize it. When the combination of technical solutions contradicts each other or cannot be realized, it should be considered that the combination of technical solutions does not exist, and is not within the protection scope of the present application.

[0046] The present application provides a burner for connecting gas and air to form a mixed gas for combustion to generate high-temperature flue gas. The burner can be used in a water heater or other electrical appliance that exchanges heat with the high-temperature flue gas. The high-temperature flue gas generated by the burner enters the inside of the water heater or other electrical appliance and exchanges heat with the heat exchanger 11 of the electrical appliance. Figures 1 to 5 The accompanying drawings correspond to the embodiments of the present application.

[0047] Please refer to Figure 1 , Figure 2 and Figure 3 In an embodiment, the burner comprises:

[0048] The burner body is formed with a first combustion chamber 70 and a second combustion chamber 80 which are connected in sequence; at least two chambers are formed inside the burner body, wherein the first combustion chamber 70 and the second combustion chamber 80 are connected with each other, the first combustion chamber 70 is used for preheating combustion, and the high-temperature flue gas formed by the preheating combustion of the first combustion chamber 70 enters the second combustion chamber 80, so that high-temperature air combustion can be carried out in the second combustion chamber 80.

[0049] The pre-distribution device 20 is arranged in the burner body and is used for accessing gas and air to form mixed gas; the pre-distribution device 20 is used for mixing the accessed gas and air to form mixed gas, and after the mixed gas is formed, the mixed gas can be supplied to the first combustion chamber 70 and the second combustion chamber 80 to realize the supply of the mixed gas according to a preset ratio. The air-fuel ratio of the mixed gas output by the pre-distribution device 20 is a first air-fuel ratio.

[0050] The preheating combustion device 30 is arranged in the burner body and is used for accessing the mixed gas input by the pre-distribution device 20 and inputting the mixed gas into the first combustion chamber 70 for preheating combustion to form high-temperature flue gas which is delivered to the second combustion chamber 80; the preheating combustion device 30 is used for inputting the mixed gas into the first combustion chamber 70 for combustion, so that high-temperature flue gas is formed in the first combustion chamber 70. The preheating combustion device 30 can adopt an existing burner structure. The preheating combustion device 30 has an air inlet, an airflow channel and an air outlet, the air inlet of the preheating combustion device 30 is connected with the pre-distribution device, the airflow with the first air-fuel ratio enters the airflow channel from the air inlet, and the airflow is input into the first combustion chamber 70 through the air outlet for preheating combustion to form high-temperature flue gas.

[0051] The gas injection assembly 50 is arranged in the burner body and is used for accessing the mixed gas input by the pre-distribution device 20 and delivering the mixed gas to the second combustion chamber 80 to enable high-temperature air combustion reaction in the second combustion chamber 80; the gas injection assembly 50 is used for accessing the mixed gas with the first air-fuel ratio input by the pre-distribution device 20.

[0052] The gas supplementing device 40 is arranged in the burner body and is connected with the gas injection assembly 50, and is used for inputting gas into the gas injection assembly 50 to make the air-fuel ratios of the preheating combustion device 30 and the gas injection assembly 50 not equal. The gas supplementing device 40 is connected with the outside of the burner and is used for supplementing gas to the gas injection assembly 50, so that the air-fuel ratio of the gas output by the gas injection assembly 50 to the second combustion chamber 80 is a second air-fuel ratio. Due to the supplementing of the gas supplementing device 40, the first air-fuel ratio is not equal to the second air-fuel ratio.

[0053] The gas supplement device 40 is used to supplement gas to the gas injection assembly 50. The air-fuel ratio of the mixed gas delivered from the pre-distribution device 20 to the preheating combustion device 30 and the gas injection assembly 50 is relatively fixed. When the gas supplement device 40 supplements gas to the gas injection assembly 50, the gas content in the mixed gas injected by the gas injection assembly 50 into the second combustion chamber 80 increases, so that the air-fuel ratio of the gas output by the preheating combustion device 30 and the gas injection assembly 50 is different.

[0054] The preheating combustion device 30 injects and burns in the first combustion chamber 70, and the combustion products are excess air and high-temperature flue gas. The combustion products enter the second combustion chamber 80. When the preset temperature in the second combustion chamber 80 is reached, the gas supplement device 40 inputs mixed gas into the second combustion chamber 80. The gas content in the mixed gas injected by the gas supplement device 40 is relatively high, and the mixed gas is formed with the combustion products of the preheating combustion device 30, forming a high-temperature and low-oxygen environment in the second combustion chamber 80.

[0055] The high-temperature air combustion reaction is carried out in the second combustion chamber 80. In the high-temperature air combustion reaction, the chemical reaction needs to occur in a high-temperature and low-oxygen environment, the temperature of the reactants is higher than the self-ignition temperature, the maximum temperature rise during combustion is lower than the self-ignition temperature, and the oxygen volume fraction is diluted to a very low concentration by the combustion products. Due to the high-temperature flue gas and excess oxygen in the combustion products of the preheating combustion device 30 entering the second combustion chamber 80, and the increased gas content in the mixed gas injected by the gas injection assembly 50 into the second combustion chamber 80, the second combustion chamber 80 can form a high-temperature and low-oxygen environment required for high-temperature air combustion reaction. Compared with conventional combustion, in this combustion state, the pyrolysis of fuel is inhibited, the flame thickness is thickened, and the flame front disappears, so that the temperature in the entire second combustion chamber 80 is very uniform, the peak combustion temperature is low, the noise is minimal, and the emissions of pollutants such as nitrogen oxides and carbon monoxide are greatly reduced. However, high-temperature air combustion requires certain conditions: the oxygen concentration in most areas of the furnace needs to be lower than a certain value, generally lower than 5% to 10%, to ensure that the gas is fully burned and the combustion is uniform, and the temperature needs to be higher than the self-ignition point of the fuel to maintain self-ignition. The preset temperature of the mixed flue gas reaches the self-ignition temperature of the gas injected by the gas injection assembly 50, so that the gas injected by the gas injection assembly 50 can maintain self-ignition in the second combustion chamber 80.

[0056] The air content of the gas injected by the gas injection assembly 50 is reduced and the fuel gas content is increased, so that the oxygen concentration in the mixed flue gas is relatively low, which is suitable for high-temperature air combustion in the second combustion chamber 80. When the fuel gas injected by the gas injection assembly 50 is subjected to high-temperature air combustion, the energy consumption required for combustion is reduced. A fan can be provided outside the burner to supplement air into the pre-distribution device 20, or other structures can be provided outside the burner to input air into the first combustion chamber 70.

[0057] In this embodiment, the pre-distribution device 20 has a fuel gas inlet 22 and an air inlet 23, and fuel gas and air enter the pre-distribution device 20 for mixing and are respectively delivered to the preheating combustion device 30 and the gas injection assembly 50. The air supplementing device 40 is used to connect a fuel gas pipeline for supplementing fuel gas to the gas injection assembly 50. A fuel gas valve 60 for supplying fuel gas can be provided outside the burner body, and the air supplementing device 40 and the pre-distribution device 20 can be connected to the fuel gas valve 60 at the same time. The first control valve 61 and the second control valve 62 are respectively provided on the fuel gas valve 60, the first control valve 61 is used to control the fuel gas delivered to the pre-distribution device 20, and the second control valve 62 is used to control the amount of fuel gas delivered to the air supplementing device 40.

[0058] The air in the first combustion chamber 70 is rapidly preheated by the preheating combustion device 30, so that the thermal load ratio of the first combustion chamber 70 is adjusted to be in the range of 20%-50% as described above, so that the emission of nitrogen oxides and carbon monoxide in the mixed flue gas formed by the first combustion chamber 70 is controlled to be about 10 ppm. Since high-temperature air combustion is a volume or diffusion combustion, its reaction rate is low, local heat release is small, heat flow distribution is uniform, combustion peak temperature is low, and noise is minimal.

[0059] Due to the preheating combustion device 30, the combustion process produces less nitrogen oxides, and the carbon monoxide produced can be fully combusted with the high-temperature air combustion reaction in the second combustion chamber 80 to improve the combustion efficiency of the gas in the second combustion chamber 80 and increase the heat release of the gas in the second combustion chamber 80. Compared with the traditional small-area local high-temperature combustion, the 16L gas water heater equipped with the burner of the embodiment carries out reaction in a large area, even in the entire second combustion chamber 80, the flame front in the second combustion chamber 80 disappears, the generation of pollutants such as nitrogen oxides and carbon monoxide is significantly reduced, the overall temperature of the second combustion chamber 80 is improved, and the radiation heat transfer is enhanced. The combustion in the second combustion chamber 80 forms high-temperature flue gas, and the heat load ratio of the second combustion chamber 80 is 50%-80%. By controlling the heat load ratio of the second combustion chamber 80 in the above range, soft combustion is achieved in the second combustion chamber 80, the purpose of low-noise combustion is achieved, and the combustion noise of the gas water heater is reduced. Due to the high-temperature flue gas generated by high-temperature air combustion, the environment pollution caused by nitrogen and carbon dioxide is also relatively reduced.

[0060] Due to the different air-fuel ratios of the preheating combustion device 30 and the gas injection assembly 50, more sufficient combustion can be achieved in the first combustion chamber 70 and the second combustion chamber 80, thereby improving the combustion efficiency of the gas, increasing the heat release, reducing the harmful gas content in the combustion products, and improving the energy utilization rate.

[0061] In the embodiment, a temperature sensor 15 is arranged in the second combustion chamber 80 for detecting the temperature in the second combustion chamber 80. When the temperature in the second combustion chamber 80 reaches a preset temperature, the gas injection assembly 50 inputs mixed gas into the second combustion chamber 80 for high-temperature air combustion, so that the second combustion chamber 80 can maintain a preheated high-temperature air combustion state.

[0062] Please refer to Figure 3 In an embodiment, the pre-distribution device 20 includes a premixer 21 arranged in the burner body for accessing gas and air to form mixed gas, and the preheating combustion device 30 and the gas injection assembly 50 are respectively connected with the premixer 21. The gas inlet 22 of the pre-distribution device 20 is used to connect the gas valve 60 to access the gas, and the air inlet 23 of the pre-distribution device 20 is used to access the air. The premixer 21 can be provided with a fan to introduce air through the fan, and the gas and air are mixed and delivered to the preheating combustion device 30 and the gas injection assembly 50.

[0063] Further optionally, the pre-distribution device 20 further comprises a pre-distribution chamber 24 arranged in the burner body and connected with the pre-mixer 21, and the pre-heating combustion device 30 and the gas injection assembly 50 are respectively connected with the pre-mixer 21 through the pre-distribution chamber 24. The pre-distribution chamber 24 is a hollow chamber arranged in the burner body. The pre-mixer 21 inputs gas and air and delivers them to the pre-distribution chamber 24, and the gas and air are fully mixed in the pre-distribution chamber 24 and are respectively delivered to the pre-heating combustion device 30 and the gas injection assembly 50, thereby realizing the output of the mixed gas. By pre-mixing, the mixing of the gas and air is more uniform, thereby improving the combustion efficiency of the gas.

[0064] Please refer to Figure 4 and Figure 5 In an embodiment, the gas injection assembly 50 comprises a housing 51 arranged in the burner body, a gas distribution chamber 52 is formed in the housing 51, the gas supplement device 40 is connected with the gas distribution chamber 52, and the housing 51 is connected with the pre-distribution device 20; and a nozzle 53 arranged in the housing 51 and communicating with the gas distribution chamber 52, the nozzle 53 is used for injecting gas to the second combustion chamber 80. The housing 51 has an air inlet and an air outlet, the air inlet and the air outlet respectively communicate with the gas distribution chamber 52, the air inlet of the housing 51 can directly communicate with the pre-distribution chamber 24 of the pre-distribution device 20, and the air outlet of the housing 51 communicates with the inside of the combustion chamber body and is used for delivering mixed gas to the second combustion chamber 80. The gas supplement device 40 is used for supplementing gas to the gas distribution chamber 52.

[0065] The gas distribution chamber 52 is used for buffering and mixing the mixed gas, so that the mixed gas can be fully mixed and uniform in the gas distribution chamber 52. When the gas injection assembly 50 is manufactured, the nozzle 53 can be arranged on the housing 51, and the nozzle 53 is connected with the gas distribution chamber 52 to realize the output of the gas. The number of the nozzles 53 can be multiple, and multiple nozzles 53 are arranged at intervals along the housing 51 to disperse the input mixed gas.

[0066] The amount of gas supplemented by the gas supplement device 40 can be adjusted by adjusting the second control valve 62. When the housing 51 is manufactured, a pressure gauge can be arranged on the gas supplement device 40 to detect the gas pressure of the gas supplement device 40.

[0067] In order to facilitate installation, in an embodiment, the gas injection assembly 50 further comprises a connecting assembly for connecting the pre-distribution device 20 and the gas distribution chamber 52. One end of the connecting assembly can be connected to the pre-distribution chamber 24 of the pre-distribution device 20, and the other end is connected to the gas distribution chamber 52 to realize gas input. The gas supplement device 40 can be connected to the gas distribution chamber 52, or can be directly connected to the connecting assembly. The connection position of the gas supplement device 40 can be determined according to the structure and distribution of the burner. By providing the connecting assembly, the connection mode of the gas injection assembly 50 can be changed according to the structure and space distribution of the burner body. The connecting assembly can be a pipeline connecting the pre-distribution device 20 and the shell 51, or can be other structural forms.

[0068] Further optionally, the connecting assembly comprises a first connecting section 54, a first gas flow passage 55 is formed in the first connecting section 54 for connecting the pre-distribution device 20; and a second connecting section 56, the first connecting section 54 is connected to the shell 51 through the second connecting section 56, a second gas flow passage 57 is formed in the second connecting section 56, the first gas flow passage 55 is connected to the gas distribution chamber 52 through the second gas flow passage 57, and the second connecting section 56 is spaced apart from the burner body. The first connecting section 54 and the second connecting section 56 are used to connect the pre-distribution device 20 and the shell 51 to form a gas flow passage between the pre-distribution device 20 and the shell 51.

[0069] The first connecting section 54 is connected to the pre-distribution device 20, and the second connecting section 56 is located between the shell 51 and the first connecting section 54. Since the second connecting section 56 is spaced apart from the burner body, the influence of the high temperature inside the burner during operation on the second connecting section 56 can be avoided. During the flow of the mixed gas from the pre-distribution device 20 to the shell 51, the heat generated by the combustion of the burner body has less influence on the gas in the second connecting section 56, thereby avoiding the problem that the mixed gas delivered to the gas distribution chamber 52 is too high in temperature and causes the gas injection assembly 50 to be easily tempered.

[0070] In the manufacturing of the gas injection assembly 50, the gas distribution chamber 52 has a first end close to the nozzle 53 and a second end away from the nozzle 53, and the second gas flow channel 57 is connected to the second end of the gas distribution chamber 52 away from the first gas flow channel 55. When the gas enters the shell 51 from the second connecting section 56, it can be away from the gas outlet end of the gas distribution chamber 52, thereby avoiding the second connecting section 56 close to the heat source, which helps to reduce the initial temperature of the gas entering the gas distribution chamber 52, thereby avoiding backfire.

[0071] The second connecting section 56 has a first side wall and a second side wall, and the second gas flow channel 57 is formed between the first side wall and the second side wall. The first side wall is close to the burner body, and the second side wall is away from the burner body. The first side wall is spaced apart from the burner body. In the manufacturing of the second connecting section 56, a heat dissipation device such as heat dissipation fins can be arranged on the side of the second side wall away from the second gas flow channel 57 for cooling the second connecting section 56 to reduce the initial temperature of the mixed gas injected by the gas injection assembly 50.

[0072] Because the second connecting section 56 is spaced apart from the burner body, the gap between the second connecting section 56 and the burner body can be used as a cooling channel for cooling the second connecting section 56, and also for cooling the outer wall of the burner body to improve the safety of the burner.

[0073] In the arrangement of the gas injection assembly 50, the gas outlet of the shell 51 can be arranged close to the first combustion chamber 70. The mixed gas injected by the gas injection assembly 50 into the burner body can quickly mix with the high-temperature flue gas generated by the preheating combustion device 30 and the excess air.

[0074] The application also provides an embodiment of a water heater.

[0075] The water heater comprises a machine body 10, a burner according to any of the above embodiments arranged in the machine body 10, and a heat exchanger 11 arranged in the machine body 10 and connected to the second combustion chamber 80 of the burner. The heat exchanger 11 is provided with a heat exchange pipe 12. The high-temperature flue gas generated by the high-temperature air combustion reaction of the burner enters the heat exchanger 11 and exchanges heat with the heat exchange pipe 12 inside the heat exchanger 11 to form hot water. The low-temperature flue gas after heat exchange is discharged.

[0076] The water heater can further comprise other functional components, such as a fume hood 13 and a fume discharge pipe 14 connected to the fume hood 13. The low-temperature flue gas produced by the heat exchanger 11 enters the fume hood 13 and is discharged through the fume discharge pipe 14.

[0077] Due to the different air-fuel ratios of the mixed gas of the preheating combustion device 30 and the gas injection assembly 50, the high-temperature air combustion reaction in the second combustion chamber 80 is more fully controllable, and the content of nitrogen oxides and carbon monoxide in the high-temperature flue gas is reduced, so that the low-temperature flue gas discharged through the fume discharge pipe 14 is less likely to cause air pollution.

[0078] The water heater can further comprise a controller, which can be used to control the operating state of the burner. Further optionally, the water heater can further comprise a temperature sensor 15 for measuring the temperature in the second combustion chamber 80, and a controller electrically connected to the body 10 and the temperature sensor 15, which is used to obtain the temperature in the second combustion chamber 80 and the required heat load of the water heater, and to control the gas injection assembly 50 to inject gas into the second combustion chamber 80 when the temperature in the second combustion chamber 80 reaches a preset temperature, so that the second combustion chamber 80 performs high-temperature air combustion to achieve the required heat load range of the water heater.

[0079] By controlling the high-temperature air combustion in the second combustion chamber 80 through the controller and injecting the mixed gas with a higher content of gas into the second combustion chamber 80 through the gas injection assembly 50, a high-temperature and low-oxygen state is formed in the second combustion chamber 80, which has a better combustion efficiency and helps to improve the energy efficiency of the water heater and save gas resources.

Claims

1. A burner, characterized in that, include: The burner body has a first combustion chamber and a second combustion chamber that are connected in sequence. A pre-distribution device, located in the burner body, is used to connect fuel gas and air to form a gas mixture; A preheating combustion device is provided on the burner body for receiving the mixed gas input from the pre-distribution device and inputting the mixed gas into the first combustion chamber for preheating combustion, so as to form high-temperature flue gas and excess air which are then transported to the second combustion chamber. A gas injection assembly, located on the burner body, is used to receive the mixed gas input from the pre-distribution device and deliver it to the second combustion chamber, so that a high-temperature air combustion reaction can occur in the second combustion chamber; as well as A gas injection device is located in the burner body and connected to the gas injection assembly. It is used to input gas into the gas injection assembly, thereby increasing the gas content in the mixed gas injected into the second combustion chamber by the gas injection assembly, so that the air-fuel ratio of the mixed gas output by the preheating combustion device is not equal to that of the mixed gas output by the gas injection assembly.

2. The burner as claimed in claim 1, characterized in that, The pre-distribution device includes: A premixer is located in the burner body and is used to introduce fuel gas and air to form a mixed gas. The preheating combustion device and the gas injection assembly are respectively connected to the premixer.

3. The burner as described in claim 2, characterized in that, The pre-distribution device further includes: A pre-distribution chamber is located in the burner body and connected to the premixer. The preheating combustion device and the gas injection assembly are respectively connected to the premixer through the pre-distribution chamber.

4. The burner as claimed in claim 1, characterized in that, The gas injection assembly includes: A housing is disposed within the burner body, a gas distribution chamber is formed within the housing, the gas supply device is connected to the gas distribution chamber, and the housing is connected to the pre-distribution device; and A nozzle is disposed in the housing and communicates with the gas distribution chamber, the nozzle being used to inject gas into the second combustion chamber.

5. The burner as described in claim 4, characterized in that, The number of nozzles is multiple, and the multiple nozzles are arranged at intervals on the housing.

6. The burner as claimed in claim 4, characterized in that, The gas injection assembly also includes: A connecting component, located on the burner body, is used to connect the pre-distribution device and the gas distribution chamber.

7. The burner as claimed in claim 6, characterized in that, The connection component includes: A first connecting section is disposed in the burner body, and a first airflow passage connecting the pre-distribution device is formed within the first connecting section; and The second connecting section connects the first connecting section to the housing. A second airflow channel is formed within the second connecting section. The first airflow channel connects to the gas distribution chamber through the second airflow channel. The distance between the second connecting section and the burner body is set.

8. The burner as claimed in claim 6 or 7, characterized in that, The gas distribution chamber has a first end near the nozzle and a second end away from the nozzle, and the end of the second airflow channel away from the first airflow channel is connected to the second end of the gas distribution chamber.

9. The burner according to any one of claims 1 to 7, characterized in that, The burner also includes: A gas valve is located on the burner body. The pre-distribution device has an air inlet and a gas inlet. The gas inlet of the pre-distribution device and the gas replenishment device are respectively connected to the gas valve.

10. A water heater, characterized in that, include: Organism; The burner as described in any one of claims 1 to 9 is disposed in the housing; and A heat exchanger is located in the machine body and is connected to the second combustion chamber of the burner.

11. The water heater as described in claim 10, characterized in that, The water heater also includes: Temperature sensor for the temperature inside the second combustion chamber; and The controller, electrically connected to the body and the temperature sensor, is used to acquire the temperature inside the second combustion chamber and the required heat load of the water heater; and is also used to control the gas injection assembly to inject gas into the second combustion chamber when the temperature inside the second combustion chamber reaches a preset temperature, so that the second combustion chamber performs high-temperature air combustion to achieve the required heat load range of the water heater.

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