Rich-lean burner and gas water heater

Abstract

The utility model discloses a rich-lean burner and a gas water heater. The rich-lean burner comprises a fire grate, a burner shell and a gas distribution rod assembly, the fire grate is arranged in the burner shell, and the side face of the burner shell is provided with a rich gas inlet and a lean gas inlet which are communicated with the fire grate. The gas distribution rod assembly is arranged on the outer side of the burner shell and used for injecting fuel gas to the thick fuel gas inlet and the thin fuel gas inlet. The combustor shell comprises a secondary air control plate located at the bottom of the combustor shell, and a plurality of through air inlet holes are formed in the secondary air control plate. The secondary air supply is performed by utilizing the secondary air control plate, so that the secondary air coefficient can be reduced, and the generation of nitrogen oxides is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of burners, in particular to a thick-thin burner and a gas water heater. Background Art

[0002] A rich-lean burner is a burner that can suppress the production of nitrogen oxides. It is currently used in many gas water heaters. The mechanism of rich-lean combustion is to make a part of the gas burn under insufficient air conditions, that is, the fuel burns too "rich", while the other part of the gas burns under excessive air conditions, that is, the fuel burns too "lean". The gas and air equivalence ratio in both cases deviates from the theoretical equivalence ratio of the combustion reaction. The oxygen concentration in the rich flame is lower, and the primary combustion temperature is lower than that at the chemical equivalence ratio, which can reduce the generation of nitrogen oxides; while the oxygen concentration in the light flame is high, but the excess air will also reduce the primary combustion temperature, thereby reducing the generation of nitrogen oxides, and ultimately reducing the total nitrogen oxides in the combustion.

[0003] However, existing rich-lean burners usually use larger openings for secondary air supply, which increases the secondary air coefficient and leads to an increase in nitrogen oxides. Utility Model Content

[0004] The utility model provides a thick-thin burner and a gas water heater. The secondary air control plate is used to supply the secondary air, so the secondary air coefficient can be reduced and the generation of nitrogen oxides can be reduced.

[0005] In order to solve the above problems, the utility model adopts the following technical solutions:

[0006] According to the first aspect of the utility model, an embodiment of the utility model provides a rich-lean burner, including a fire grate, a burner housing and a gas distribution rod assembly, wherein the fire grate is arranged in the burner housing, and the side of the burner housing is provided with a rich gas inlet and a lean gas inlet connected to the fire grate, and the gas distribution rod assembly is arranged on the outside of the burner housing and is used to inject gas to both the rich gas inlet and the lean gas inlet; the burner housing includes a secondary air control plate located at the bottom thereof, and the secondary air control plate is provided with a plurality of penetrating air inlet holes.

[0007] In some embodiments, the air inlet holes are provided in two groups, each group of air inlet holes includes a plurality of air inlet holes, the air inlet holes included in the two groups of air inlet holes are distributed in a rectangular shape, and one group of air inlet holes is located inside the other group of air inlet holes.

[0008] In some embodiments, the gas distributor rod assembly includes a gas distributor rod, an air intake passage, a first switch valve and a second switch valve; a plurality of nozzle groups are arranged on the surface of the gas distributor rod along the length direction of the gas distributor rod, and each nozzle group includes a thick nozzle and a thin nozzle; a first cavity, a second cavity, a third cavity and a connecting cavity are arranged in the gas distributor rod, and the air intake passage is connected to the first cavity and the connecting cavity, the first switch valve is used to control the connection between the connecting cavity and the second cavity or the isolation between the connecting cavity and the second cavity, and the second switch valve is used to control the connection between the connecting cavity and the third cavity or the isolation between the connecting cavity and the third cavity; the nozzle groups include several first nozzle groups connected to the first cavity, several second nozzle groups connected to the second cavity and multiple third nozzle groups connected to the third cavity, and the number of the third nozzle groups is greater than the number of the second nozzle groups.

[0009] In some embodiments, the thick nozzles and the thin nozzles included in each nozzle group are distributed in the up-down direction, all the thick nozzles are arranged in a row along the length direction of the gas splitter rod, and all the thin nozzles are also arranged in a row along the length direction of the gas splitter rod.

[0010] In some embodiments, the third cavity, the first cavity and the second cavity are arranged along the length direction of the gas dividing rod.

[0011] In some embodiments, the first cavity partially overlaps with an extended path of the air inlet channel, and an inner wall of the first cavity is provided with a first opening connecting the air inlet channel and the first cavity, and the first opening is located on the extended path of the air inlet channel.

[0012] In some embodiments, the side wall of the second cavity is provided with a second opening connected to the connecting cavity, and the side wall of the third cavity is provided with a third opening connected to the connecting cavity; the first switch valve and the second switch valve both include a movable valve core, when the valve core of the first switch valve blocks the second opening, the connecting cavity is connected to the second cavity, when the valve core of the first switch valve is separated from the second opening, the connecting cavity is separated from the second cavity; when the valve core of the second switch valve blocks the third opening, the connecting cavity is connected to the third cavity, when the valve core of the second switch valve is separated from the third opening, the connecting cavity is separated from the third cavity.

[0013] In some embodiments, the first nozzle group and the second nozzle group are each provided with two nozzles, and the third nozzle group is provided with five nozzles.

[0014] According to the second aspect of the utility model, an embodiment of the utility model provides a gas water heater, comprising a heat exchanger, an exhaust hood, a fan and a thick-lean burner as described in any one of the first aspect above, wherein the heat exchanger is fixed on the top of the burner housing, the exhaust hood is arranged on the top of the heat exchanger, and the fan is connected to the exhaust hood and is used to draw the air in the exhaust hood outward.

[0015] In some embodiments, the heat exchanger includes a heat exchanger shell and a coil wound around the outside of the heat exchanger shell, wherein the coil winds around the heat exchanger shell twice.

[0016] The utility model has at least the following beneficial effects: a rich gas inlet and a lean gas inlet connected to the fire grate are arranged on the side of the burner shell, and a gas distribution rod assembly is arranged on the outside of the burner shell and is used to inject gas to both the rich gas inlet and the lean gas inlet, so that the fire grate can form rich and lean combustion; and the burner shell includes a secondary air control plate located at the bottom thereof, and the secondary air control plate is provided with a plurality of penetrating air inlet holes, and secondary air is supplemented through the air inlet holes at the bottom of the burner shell, and the size of the air inlet holes is much smaller than that of the traditional opening structure, which can reduce the secondary air coefficient and reduce the generation of nitrogen oxides. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic structural diagram of a rich-lean burner according to an embodiment of the utility model;

[0018] Figure 2 This is a structural schematic diagram of a secondary air control plate in one embodiment of the utility model;

[0019] Figure 3 This is a structural schematic diagram of an air distribution rod assembly according to an embodiment of the utility model;

[0020] Figure 4 It is a cross-sectional schematic diagram of a gas distribution rod assembly according to an embodiment of the utility model;

[0021] Figure 5 It is a cross-sectional schematic diagram of the gas distribution rod assembly of one embodiment of the utility model after removing the first switch valve and the second switch valve;

[0022] Figure 6 This is a schematic diagram of the structure of a gas water heater according to an embodiment of the utility model;

[0023] Figure 7 The utility model is a schematic structural diagram of a heat exchanger according to an embodiment of the present invention.

[0024] Wherein, the accompanying drawings are marked as follows:

[0025] Burner housing 10, rich gas inlet 11, lean gas inlet 12, secondary air control plate 13, air inlet 14; gas distribution rod assembly 20; heat exchanger 30, heat exchanger housing 31, coil 32; exhaust hood 40; fan 50;

[0026] The gas distribution rod 100, the first cavity 110, the first opening 111, the second cavity 120, the second opening 121, the third cavity 130, the third opening 131, and the connecting cavity 140;

[0027] Intake passage 200,

[0028] A first switch valve 310, a second switch valve 320;

[0029] The thick nozzle 401 , the thin nozzle 402 , the first nozzle group 410 , the second nozzle group 420 , and the third nozzle group 430 . DETAILED DESCRIPTION

[0030] The utility model provides the following description with reference to the accompanying drawings to help fully understand the various embodiments of the utility model as defined by the claims and their equivalents. The description includes various specific details to help understanding, but these details should be regarded as exemplary only. Therefore, those skilled in the art will recognize that various changes and modifications can be made to the various embodiments described herein without departing from the scope and spirit of the utility model.

[0031] In the description of the present invention, descriptions of orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the drawings and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0032] It will be understood that when one element (eg, a first element) is “connected” to another element (eg, a second element), the element may be directly connected to the other element or an intervening element (eg, a third element) may be present between the element and the other element.

[0033] The embodiment of the utility model provides a thick-thin burner, such as Figure 1 and Figure 2As shown, it includes a fire grate, a burner housing 10 and a gas distribution rod assembly 20. The fire grate is arranged in the burner housing 10, and the burner housing 10 encloses a combustion chamber. The side of the burner housing 10 is provided with a rich gas inlet 11 and a lean gas inlet 12 connected to the fire grate. The gas distribution rod assembly 20 is arranged on the outside of the burner housing 10 and is used to inject gas to both the rich gas inlet 11 and the lean gas inlet 12, so that the fire grate can form rich and lean combustion. The burner housing 10 includes a secondary air control plate 13 located at the bottom thereof, and the secondary air control plate 13 is provided with a plurality of air inlet holes 14 penetrating the secondary air control plate 13, and the air inlet holes 14 are connected to the inner space of the burner housing 10. External air can enter the inner side of the burner housing 10 through the air inlet holes 14 at the bottom of the burner housing 10 to supplement the fire grate with secondary air, and the size of the air inlet holes 14 is much smaller than the traditional opening structure, which can reduce the secondary air coefficient and reduce the generation of nitrogen oxides.

[0034] In some embodiments, two groups of air inlet holes 14 are provided, each group of air inlet holes includes a plurality of air inlet holes 14, the air inlet holes 14 included in the two groups of air inlet holes are distributed in a rectangular shape, and one group of air inlet holes is located inside the other group of air inlet holes. Such arrangement of the air inlet holes 14 can reduce the number of air inlet holes 14 and the supply of secondary air. At the same time, the secondary air mainly flows upward from the surroundings of the fire grate, which can further reduce the secondary air coefficient and reduce the generation of nitrogen oxides.

[0035] In some embodiments, the gas distribution rod assembly 20 can be fixed to the outer side of the burner housing 10 through a support plate so that the gas distribution rod assembly 20 is spaced a certain distance from the rich gas inlet 11 and the lean gas inlet 12 to allow primary air to enter the fire grate.

[0036] In some embodiments, Figure 3-5 As shown, the gas distribution rod assembly includes a gas distribution rod 100, an air inlet channel 200, a first switch valve 310 and a second switch valve 320. The surface of the gas distribution rod 100 is arranged with a plurality of nozzle groups along the length direction of the gas distribution rod 100, and each nozzle group includes a rich nozzle 401 and a lean nozzle 402, the rich nozzle 401 is used to guide the gas toward the rich gas inlet, and the lean nozzle 402 is used to guide the gas toward the lean gas inlet. Since the fire row monolithic pieces are usually arranged neatly, the arrangement of the nozzle groups along the length direction of the gas distribution rod 100 can adapt to the arrangement of the fire row monolithic pieces. The nozzle group includes a plurality of first nozzle groups 410, a plurality of second nozzle groups 420 and a plurality of third nozzle groups 430, and each of the first nozzle group 410, the second nozzle group 420 and the third nozzle group 430 includes a rich nozzle 401 and a lean nozzle 402.

[0037] The gas distribution rod 100 is provided with a first cavity 110, a second cavity 120, a third cavity 130 and a connecting cavity 140, and the first cavity 110, the second cavity 120 and the third cavity 130 are independent of each other. The air inlet channel 200 is connected with the first cavity 110, and the air inlet channel 200 is also connected with the connecting cavity 140, and the gas is input from the air inlet channel 200 and then flows to the first cavity 110 and the connecting cavity 140. The first switch valve 310 and the second switch valve 320 can be fixed on the gas distribution rod 100, and the first switch valve 310 is used to control the connection between the connecting cavity 140 and the second cavity 120 or the connection between the connecting cavity 140 and the second cavity 120. When the connecting cavity 140 is connected with the second cavity 120, the gas in the connecting cavity 140 can flow to the second cavity 120, and when the connecting cavity 140 is isolated from the second cavity 120, there is no gas supply to the second cavity 120. The second switch valve 320 is used to control the connection between the connecting cavity 140 and the third cavity 130 or to isolate the connecting cavity 140 from the third cavity 130; when the connecting cavity 140 and the third cavity 130 are connected, the gas in the connecting cavity 140 flows to the third cavity 130, and when the connecting cavity 140 and the third cavity 130 are isolated, there is no gas supply to the third cavity 130. The first cavity 110 is connected to the first nozzle group 410, the second cavity 120 is connected to the second nozzle group 420, and the third cavity 130 is connected to the third nozzle group 430, and the number of the third nozzle group 430 is greater than the number of the second nozzle group 420.

[0038] When the first switch valve 310 and the second switch valve 320 are both closed, only the first nozzle group 410 draws gas, so that the burner works at the first gear; when the first switch valve 310 is opened and the second switch valve 320 is closed, the first nozzle group 410 and the second nozzle group 420 both draw gas, so that the burner works at the second gear, and the heat load of the second gear is greater than the heat load of the first gear; when the first switch valve 310 is closed and the second switch valve 320 is opened, the first nozzle group 410 and the third nozzle group 430 draw gas, so that the burner works at the third gear, because the number of the third nozzle group 430 is greater than the number of the second nozzle group 420, the heat load of the third gear is greater than the heat load of the second gear; when the first switch valve 310 and the second switch valve 320 are both opened, the first nozzle group 410, the second nozzle group 420 and the third nozzle group 430 all draw gas, and the burner works at the fourth gear with the maximum heat load. Therefore, this embodiment can realize four-segment heat load control, which improves the user experience.

[0039] In some embodiments, the air intake passage 200 may be enclosed by an air intake pipe, which is connected to the air dividing rod 100 , or the inner space of the air dividing rod 100 may be enclosed to form the air intake passage 200 .

[0040] In some embodiments, the thick nozzles 401 and the thin nozzles 402 included in each nozzle group are distributed in the up-down direction, and all the thick nozzles 401 are arranged in a row along the length direction of the gas distribution rod 100, and all the thin nozzles 402 are also arranged in a row along the length direction of the gas distribution rod 100, so as to form a two-row nozzle structure. The relative positions of the thick nozzles 401 and the thin nozzles 402 are kept uniform, and each single piece of the fire row can adopt the same structure to reduce the manufacturing difficulty and facilitate the overall assembly.

[0041] In some embodiments, the third cavity 430, the first cavity 410 and the second cavity 420 are arranged along the length direction of the gas dividing rod 100, which is the same as the arrangement direction of the nozzle group, so as to adapt to the distribution of the first nozzle group 410, the second nozzle group 420 and the third nozzle group 430, shorten the connection path between the nozzle group and the corresponding cavity, simplify the pipeline setting, and make the entire structure more compact.

[0042] Furthermore, the arrangement direction of the third nozzle group 430, the first nozzle group 410 and the second nozzle group 420 is the same as the arrangement direction of the third cavity 430, the first cavity 410 and the second cavity 420 to further adapt to each other and shorten the connection path between the nozzle group and the corresponding cavity.

[0043] In some embodiments, the first cavity 110 partially overlaps with the extended path of the air inlet channel 200, and the inner wall of the first cavity 110 is provided with a first opening 111 connecting the air inlet channel 200 and the first cavity 110, and the first opening 111 is located on the extended path of the air inlet channel 200. Since the first cavity 110 partially overlaps with the extended path of the air inlet channel 200, the positional relationship between the first cavity 110 and the air inlet channel 200 is relatively more compact, which can improve the compactness of the entire gas distribution rod assembly. At the same time, the first opening 111 is located on the extended path of the air inlet channel 200, and the gas in the air inlet channel 200 can easily enter the first cavity 110 directly.

[0044] In some embodiments, the side wall of the second cavity 120 is provided with a second opening 121 communicating with the connecting cavity 140, and the side wall of the third cavity 130 is provided with a third opening 131 communicating with the connecting cavity 140. The first switch valve 310 and the second switch valve 320 both include a movable valve core. When the valve core of the first switch valve 310 blocks the second opening 121, the connecting cavity 140 is communicated with the second cavity 120. When the valve core of the first switch valve 310 is separated from the second opening 121, the connecting cavity 140 is separated from the second cavity 120. When the valve core of the second switch valve 320 blocks the third opening 131, the connecting cavity 140 is communicated with the third cavity 130. When the valve core of the second switch valve 320 is separated from the third opening 131, the connecting cavity 140 is separated from the third cavity 130. Thus, the connecting cavity 140 is connected to the second cavity 120 or is isolated from the second cavity 120 and the connecting cavity 140 is connected to the third cavity 130 or is isolated from the third cavity 130. The first switch valve 310 and the second switch valve 320 can both be solenoid valves.

[0045] In some embodiments, the first nozzle group 410 and the second nozzle group 420 are each provided with two, and the third nozzle group 430 is provided with five, thereby forming a 2-4-7-9 segmentation, and the overlapping area of ​​the heat load is relatively large. When the gas distribution rod assembly of this embodiment is used in a water heater, the water temperature fluctuation when switching segments can be reduced, and the water temperature can be prevented from being too low or too high, thereby meeting the user's various water needs.

[0046] The embodiment of the utility model also provides a gas water heater, such as Figure 6 and Figure 7 As shown, it includes a heat exchanger 30, an exhaust hood 40, a fan 50 and a rich-lean burner of any of the above embodiments. The specific description of the rich-lean burner can refer to the above embodiments and will not be repeated here.

[0047] The heat exchanger 30 is fixed on the top of the burner housing 10 so that the flame generated by the fire row can heat the heat exchanger 30. The exhaust hood 40 is set on the top of the heat exchanger 30 so that the hot air can pass through the heat exchanger 30 and flow to the exhaust hood 40. The fan 50 is connected to the exhaust hood 40 and is used to draw the air in the exhaust hood 40 outward, thereby forming a strong exhaust structure. Under the action of the fan 50, the outside air can enter the inner side of the burner housing 10 through the air inlet hole at the bottom of the burner housing 10, and the hot air flows upward. The use of a strong exhaust structure can reduce resonance and reduce noise.

[0048] In some embodiments, the heat exchanger includes a heat exchanger housing 31 and a coil 32 wound around the outside of the heat exchanger housing 31, and the coil 32 is wound around the heat exchanger housing 31 twice. The heat of the heat exchanger housing 31 is absorbed by the coil 32, which reduces the problem of discoloration of the heat exchanger housing 31 when heated.

[0049] The terms and words used in the above description and claims are not limited to the literal meanings, but are only used by the applicant to enable a clear and consistent understanding of the utility model. Therefore, it should be clear to those skilled in the art that the above description of various embodiments of the utility model is provided only for illustration, and not for limiting the utility model as defined by the attached claims and their equivalents.

Claims

1. A rich-lean burner, characterized in that: It includes a fire grate, a burner shell and a gas distribution rod assembly, wherein the fire grate is arranged in the burner shell, and the side of the burner shell is provided with a rich gas inlet and a light gas inlet connected to the fire grate, and the gas distribution rod assembly is arranged on the outside of the burner shell and is used for injecting gas to both the rich gas inlet and the light gas inlet; the burner shell includes a secondary air control plate located at the bottom thereof, and the secondary air control plate is provided with a plurality of penetrating air inlet holes.

2. The rich-lean burner according to claim 1, characterized in that: The air inlet holes are arranged in two groups, each group of air inlet holes includes a plurality of air inlet holes, the air inlet holes included in the two groups of air inlet holes are distributed in a rectangular shape, and one group of air inlet holes is located inside the other group of air inlet holes.

3. The rich-lean burner according to claim 1, characterized in that: The gas distributor rod assembly includes a gas distributor rod, an air intake passage, a first switch valve and a second switch valve; a plurality of nozzle groups are arranged on the surface of the gas distributor rod along the length direction of the gas distributor rod, and each nozzle group includes a thick nozzle and a thin nozzle; a first cavity, a second cavity, a third cavity and a connecting cavity are arranged in the gas distributor rod, and the air intake passage is connected with the first cavity and the connecting cavity, the first switch valve is used to control the connection between the connecting cavity and the second cavity or the isolation between the connecting cavity and the second cavity, and the second switch valve is used to control the connection between the connecting cavity and the third cavity or the isolation between the connecting cavity and the third cavity; the nozzle groups include a plurality of first nozzle groups connected with the first cavity, a plurality of second nozzle groups connected with the second cavity and a plurality of third nozzle groups connected with the third cavity, and the number of the third nozzle groups is greater than the number of the second nozzle groups.

4. The rich-lean burner according to claim 3, characterized in that: The thick nozzles and the thin nozzles included in each nozzle group are distributed in the up-down direction, all the thick nozzles are arranged in a row along the length direction of the gas dividing rod, and all the thin nozzles are also arranged in a row along the length direction of the gas dividing rod.

5. The rich-lean burner according to claim 3, characterized in that: The third cavity, the first cavity and the second cavity are arranged along the length direction of the gas dividing rod.

6. The rich-lean burner according to claim 3, characterized in that: The first cavity partially overlaps with the extended path of the air intake channel, and the inner wall of the first cavity is provided with a first opening connecting the air intake channel and the first cavity, and the first opening is located on the extended path of the air intake channel.

7. The rich-lean burner according to claim 3, characterized in that: The side wall of the second cavity is provided with a second opening connected to the connecting cavity, and the side wall of the third cavity is provided with a third opening connected to the connecting cavity; the first switch valve and the second switch valve both include a movable valve core, when the valve core of the first switch valve blocks the second opening, the connecting cavity is connected to the second cavity, when the valve core of the first switch valve is separated from the second opening, the connecting cavity is separated from the second cavity; when the valve core of the second switch valve blocks the third opening, the connecting cavity is connected to the third cavity, when the valve core of the second switch valve is separated from the third opening, the connecting cavity is separated from the third cavity.

8. The rich-lean burner according to any one of claims 3 to 7, characterized in that: The first nozzle group and the second nozzle group are each provided with two nozzles, and the third nozzle group is provided with five nozzles.

9. A gas water heater, characterized in that: It comprises a heat exchanger, an exhaust hood, a fan and a rich-lean burner as described in any one of claims 1 to 8, wherein the heat exchanger is fixed on the top of the burner housing, the exhaust hood is arranged on the top of the heat exchanger, and the fan is connected to the exhaust hood and is used to draw the air in the exhaust hood outwards.

10. The gas water heater according to claim 9, characterized in that: The heat exchanger comprises a heat exchanger shell and a coil wound around the outer side of the heat exchanger shell, wherein the coil is wound around the heat exchanger shell twice.

Images