Combustor
By using the rich-lean offset combustion technology, which utilizes the rich-lean combustion mixing chamber and the flame hole offset combustion, the problem of high economic cost or low efficiency of existing low NOx burners is solved, and efficient and low-cost NOx emission reduction and combustion performance improvement are achieved.
Patent Information
- Application Number
- CN202520015730.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-03
- Publication Date
- 2025-12-30
- Estimated Expiration
- 2035-01-03
AI Technical Summary
Existing low-NOx burners reduce nitrogen oxide emissions by removing or lowering flame temperature, which leads to increased economic costs or reduced combustion efficiency.
The system employs a rich-lean offset combustion technology, which involves setting up rich combustion mixing chambers and lean combustion mixing chambers on the burner. The rich combustion burner holes and lean combustion burner holes partially offset each other, increasing the amount of primary air introduced, reducing the demand for secondary air, improving combustion efficiency, and suppressing NOx formation.
Without increasing economic costs, it effectively reduces NOx emissions, improves combustion efficiency and performance, increases the flame-cooker exchange area, and facilitates cleaning of spills.
Smart Images
Figure CN223740783U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the field of cooking utensils, in particular to a burner. BACKGROUND
[0002] In order to reduce the emission of nitrogen oxides (NOx) in the combustion process of household gas stoves, some low-NOx burners on the market are achieved by removing the NOx generated in the combustion process, but this method will produce additional economic costs and reduce efficiency. Some low-NOx burners on the market are achieved by reducing the flame temperature to reduce NOx, but this method will reduce the efficiency of combustion. SUMMARY
[0003] The technical problem to be solved by the utility model is to overcome the defects of the prior art and provide a burner.
[0004] The utility model solves the above technical problem by the following technical scheme:
[0005] A burner, comprising:
[0006] A mixing chamber having a plurality of rich combustion mixing chambers and a plurality of lean combustion mixing chambers, the rich combustion mixing chambers and the lean combustion mixing chambers being independently arranged and alternately arranged along the radial direction of the mixing chamber;
[0007] A fire cover placed at the upper end of the mixing chamber, the fire cover comprising a rich combustion fire cover and a lean combustion fire cover, the rich combustion fire cover covering the rich combustion mixing chambers, the lean combustion fire cover covering the lean combustion mixing chambers, and the rich combustion fire holes of the rich combustion fire cover being at least partially arranged opposite to the lean combustion fire holes of the adjacent lean combustion fire cover;
[0008] The projection of the fire cover along its axial direction on the mixing chamber completely overlaps the mixing chamber.
[0009] In this scheme, the rich combustion fire holes of the rich combustion fire cover are at least partially arranged opposite to the lean combustion fire holes of the adjacent lean combustion fire cover, so that the rich flame at the rich combustion fire holes can be counter-fired with the lean flame at the lean combustion fire holes, making the gas combustion more sufficient, thereby inhibiting the generation of NOx in the combustion process, reducing the emission of NOx, without additional economic costs and without reducing the combustion efficiency. Since the burner can introduce more primary air, the amount of secondary air required for combustion can be reduced, so that the fire cover can completely cover the mixing chamber, without the need for additional design of a secondary air supplement channel, increasing the exchange area of the flame and the pot, improving the combustion performance, and facilitating the cleaning of liquid overflow and other problems.
[0010] Preferably, the rich combustion fire cover comprises a first rich combustion fire cover, a second rich combustion fire cover and a third rich combustion fire cover, the lean combustion fire cover comprises a first lean combustion fire cover and a second lean combustion fire cover; from the radial outer side of the fire cover to the radial inner side of the fire cover, the first rich combustion fire cover, the first lean combustion fire cover, the second rich combustion fire cover, the second lean combustion fire cover and the third rich combustion fire cover abut in turn.
[0011] The rich combustion gas mixing chamber comprises a first rich combustion gas mixing chamber, a second rich combustion gas mixing chamber and a third rich combustion gas mixing chamber, and the lean combustion gas mixing chamber comprises a first lean combustion gas mixing chamber and a second lean combustion gas mixing chamber; from the radial outer side of the fire cover to the radial inner side of the fire cover, the first rich combustion gas mixing chamber, the first lean combustion gas mixing chamber, the second rich combustion gas mixing chamber, the second lean combustion gas mixing chamber and the third rich combustion gas mixing chamber are arranged in turn.
[0012] The first rich combustion fire cover covers the first rich combustion gas mixing chamber, the first lean combustion fire cover covers the first lean combustion gas mixing chamber, the second rich combustion fire cover covers the second rich combustion gas mixing chamber, the second lean combustion fire cover covers the second lean combustion gas mixing chamber, and the third rich combustion fire cover covers the third rich combustion gas mixing chamber.
[0013] In the scheme, on the one hand, the above arrangement can increase the number of fire holes, increase the exchange area of the flame and the pot, and improve the combustion performance. On the other hand, the amount of introduced primary air can be increased by increasing the number of gas mixing chambers, thereby reducing the required secondary air for combustion.
[0014] Preferably, the inner circumferential wall of the first rich combustion fire cover is provided with a first rich combustion fire hole, and the inner circumferential wall of the first rich combustion fire cover is inclined downward from top to bottom towards the radial inner side of the fire cover.
[0015] The outer circumferential wall and the inner circumferential wall of the first lean combustion fire cover are provided with first lean combustion fire holes, the outer circumferential wall of the first lean combustion fire cover is inclined downward from top to bottom towards the radial outer side of the fire cover, and the inner circumferential wall of the second lean combustion fire cover is inclined downward from top to bottom towards the radial inner side of the fire cover.
[0016] The outer circumferential wall of the second rich combustion fire cover is provided with a second rich combustion fire hole, and the outer circumferential wall of the second rich combustion fire cover is inclined downward from top to bottom towards the radial outer side of the fire cover.
[0017] In the scheme, the first rich combustion fire hole and the first lean combustion fire hole are oppositely arranged, and the second rich combustion fire hole and the second lean combustion fire hole are oppositely arranged to perform offset combustion, so that gas combustion is more sufficient, thereby inhibiting the generation of NOx during the combustion process and reducing the emission of NOx.
[0018] Preferably, the second weak-burning fire cover is provided with a second weak-burning fire hole on the upper end wall of the second weak-burning fire cover, and the upper end wall of the second weak-burning fire cover is parallel to the horizontal plane.
[0019] The third strong-burning fire cover is provided with a third strong-burning fire hole on the outer peripheral wall of the third strong-burning fire cover, and the outer peripheral wall of the third strong-burning fire cover is inclined from top to bottom towards the radial outside of the fire cover.
[0020] Preferably, the second strong-burning fire cover and the second weak-burning fire cover are integrally formed.
[0021] In the present scheme, the above arrangement can reduce the number of fire covers, facilitate installation, and make the overall integrity of the fire cover better.
[0022] Preferably, the first strong-burning gas mixing chamber and the second strong-burning gas mixing chamber are in communication.
[0023] In the present scheme, the gas concentration in the first strong-burning gas mixing chamber and the second strong-burning gas mixing chamber is substantially the same, so that the flame concentration generated is substantially the same, and the heating of the cookware is more uniform.
[0024] Preferably, the gas mixing chamber further comprises a communication passage, the communication passage is arranged below the first weak-burning gas mixing chamber, and both ends of the communication passage penetrate into the first strong-burning gas mixing chamber and the second strong-burning gas mixing chamber, respectively.
[0025] In the present scheme, the communication passage is arranged below the first weak-burning gas mixing chamber to prevent interference between the communication passage and the first weak-burning gas mixing chamber, thereby preventing the gas in the communication passage from mixing into the first weak-burning gas mixing chamber.
[0026] Preferably, the communication passage penetrates the lower end wall of the gas mixing chamber, and the burner further comprises a base, and the upper end surface of the base abuts against the lower end surface of the gas mixing chamber.
[0027] In the present scheme, the base can block the lower end opening of the communication passage, so that the gas in the communication passage can only flow between the first strong-burning gas mixing chamber and the second strong-burning gas mixing chamber, thereby improving safety.
[0028] Preferably, the burner further comprises a nozzle seat, a plurality of nozzles, a plurality of injection pipes, and a plurality of injection pipe mounting seats, the number of the nozzles, the injection pipes, and the injection pipe mounting seats is the same and they are arranged one-to-one.
[0029] The plurality of nozzles are fixed on the nozzle seat, the plurality of injection pipe mounting seats are fixed on the lower end surface of the base, one end of the injection pipe is connected with the corresponding injection pipe mounting seat, and the other end of the injection pipe extends towards the corresponding nozzle.
[0030] Preferably, the ejector pipe includes a rich combustion ejector pipe and a lean combustion ejector pipe, and a port diameter of the rich combustion ejector pipe toward the one end of the nozzle is smaller than a port diameter of the lean combustion ejector pipe toward the one end of the nozzle.
[0031] In the present scheme, the above arrangement enables the lean combustion ejector pipe to introduce more primary air, thereby increasing the excess air ratio and reducing the flame concentration.
[0032] The positive progress effect of the utility model lies in: the rich combustion fire hole of the rich combustion fire cover and the lean combustion fire hole of the adjacent lean combustion fire cover are at least partially oppositely arranged, so that the rich flame at the rich combustion fire hole can be counter-burned with the lean flame at the lean combustion fire hole, the gas combustion is more sufficient, the generation of NOx can be inhibited in the combustion process, the emission of NOx is reduced, no additional economic cost is generated, and the combustion efficiency is not reduced. BRIEF DESCRIPTION OF DRAWINGS
[0033] Figure 1 It is a three-dimensional structure schematic view of the burner of an embodiment of the utility model.
[0034] Figure 2 It is another three-dimensional structure schematic view of the burner of an embodiment of the utility model.
[0035] Figure 3 It is an internal structure schematic view of the burner of an embodiment of the utility model.
[0036] Figure 4 It is a three-dimensional structure schematic view of the mixing chamber of an embodiment of the utility model.
[0037] Figure 5 It is another three-dimensional structure schematic view of the mixing chamber of an embodiment of the utility model.
[0038] Figure 6 It is a three-dimensional structure schematic view of the first rich combustion fire cover of an embodiment of the utility model.
[0039] Figure 7 It is another three-dimensional structure schematic view of the first rich combustion fire cover of an embodiment of the utility model.
[0040] Figure 8 It is a three-dimensional structure schematic view of the first lean combustion fire cover of an embodiment of the utility model.
[0041] Figure 9Another perspective structural schematic view of the first weak combustion fire cover of the embodiment of the present utility model.
[0042] Figure 10 The perspective structural schematic view of the second strong combustion fire cover and the second weak combustion fire cover cooperation of the embodiment of the present utility model.
[0043] Figure 11 Another perspective structural schematic view of the second strong combustion fire cover and the second weak combustion fire cover cooperation of the embodiment of the present utility model.
[0044] Figure 12 The perspective structural schematic view of the third strong combustion fire cover of the embodiment of the present utility model.
[0045] Figure 13 Another perspective structural schematic view of the third strong combustion fire cover of the embodiment of the present utility model.
[0046] Figure 14 The perspective structural schematic view of the base of the embodiment of the present utility model.
[0047] Figure 15 Another perspective structural schematic view of the base of the embodiment of the present utility model.
[0048] Figure 16 The perspective structural schematic view of the nozzle mounting seat of the embodiment of the present utility model.
[0049] Explanation of reference signs:
[0050] Gas mixing chamber 1
[0051] First strong combustion gas mixing chamber 11
[0052] Second strong combustion gas mixing chamber 12
[0053] Third strong combustion gas mixing chamber 13
[0054] First weak combustion gas mixing chamber 14
[0055] Second weak combustion gas mixing chamber 15
[0056] Communication passage 16
[0057] First strong combustion fire cover 21
[0058] Second strong combustion fire cover 22
[0059] Third strong combustion fire cover 23
[0060] First weak combustion fire cover 24
[0061] Second weak combustion fire cover 25
[0062] Base 3
[0063] induction needle 4
[0064] nozzle seat 51
[0065] air inlet joint 52
[0066] nozzle 53
[0067] ejector tube 6
[0068] rich combustion ejector tube 61
[0069] lean combustion ejector tube 62
[0070] ejector tube mounting seat 7
[0071] first rich combustion port 81
[0072] second rich combustion port 82
[0073] third rich combustion port 83
[0074] first lean combustion port 84
[0075] second lean combustion port 85 DETAILED DESCRIPTION
[0076] A preferred embodiment is described below in conjunction with the accompanying drawings so as to provide a more thorough understanding of the present application.
[0077] As Figures 1-3 shown, the present embodiment discloses a burner for a stove, specifically a low-NOx burner, which adopts the principle of rich-lean counter-burning to improve combustion performance, inhibit the generation of NOx, and reduce the emission of NOx.
[0078] Among them, the rich-lean combustion refers to mixing fuel at different ratios with primary air at different nozzle outlets of a group of burners, a part of the fuel is burned under the condition that the excess air coefficient is greater than 1 (air supply is excessive), forming a lean flame; another part of the fuel is burned under the condition that the excess air coefficient is less than 1 (air supply is insufficient), forming a rich flame, and the total excess air coefficient of the two combustion is controlled within a reasonable range, so as to realize the combustion mode of fuel rich-lean separation.
[0079] Specifically, as Figures 1-3 shown, the burner includes a mixing chamber 1, a fire cover, a base 3, an induction needle 4, a nozzle seat 51, a nozzle 53, an ejector tube 6, and an ejector tube mounting seat 7. The fire cover is placed at the upper end of the mixing chamber 1, used to block the upper end opening of the mixing cavity in the mixing chamber 1, and the base 3 is fixed at the lower end of the mixing chamber 1.
[0080] As Figures 3-5As shown, the gas mixing chamber 1 has a rich combustion gas mixing chamber and a lean combustion gas mixing chamber, which are independent of each other and arranged alternately along the radial direction of the gas mixing chamber 1, i.e., the rich combustion gas mixing chamber and the lean combustion gas mixing chamber are not communicated with each other. Among them, the gas mixing chamber 1 and the fire cover are coaxially arranged.
[0081] Specifically, as shown in Figure 3 and Figure 4 , the rich combustion gas mixing chamber includes a first rich combustion gas mixing chamber 11, a second rich combustion gas mixing chamber 12 and a third rich combustion gas mixing chamber 13, and the lean combustion gas mixing chamber includes a first lean combustion gas mixing chamber 14 and a second lean combustion gas mixing chamber 15. The first rich combustion gas mixing chamber 11, the second rich combustion gas mixing chamber 12, the first lean combustion gas mixing chamber 14 and the second lean combustion gas mixing chamber 15 are all annular chambers, and the third rich combustion gas mixing chamber 13 is a circular chamber. From the radial outside of the fire cover to the radial inside of the fire cover, the first rich combustion gas mixing chamber 11, the first lean combustion gas mixing chamber 14, the second rich combustion gas mixing chamber 12, the second lean combustion gas mixing chamber 15 and the third rich combustion gas mixing chamber 13 are arranged in sequence.
[0082] Further, as shown in Figure 3 and Figure 5 , the first rich combustion gas mixing chamber 11 is communicated with the second rich combustion gas mixing chamber 12, so that the gas concentration in the first rich combustion gas mixing chamber 11 and the second rich combustion gas mixing chamber 12 is substantially the same, thereby producing a flame with substantially the same concentration, so that the pot is heated more uniformly.
[0083] Specifically, as shown in Figure 3 and Figure 5 , the gas mixing chamber 1 further includes a communication passage 16, which is arranged below the first lean combustion gas mixing chamber 14, and the two ends of the communication passage 16 respectively penetrate into the first rich combustion gas mixing chamber 11 and the second rich combustion gas mixing chamber 12. In this embodiment, the communication passage 16 is arranged below the first lean combustion gas mixing chamber 14 to prevent the communication passage 16 from interfering with the first lean combustion gas mixing chamber 14, thereby preventing the gas in the communication passage 16 from mixing into the first lean combustion gas mixing chamber 14.
[0084] Further, as shown in Figure 3 and Figure 5 , the communication passage 16 penetrates the lower end wall of the gas mixing chamber 1; the burner further includes a base 3, and the upper end surface of the base 3 abuts against the lower end surface of the gas mixing chamber 1. The base 3 can block the lower end opening of the communication passage 16, so that the gas in the communication passage 16 can only flow between the first rich combustion gas mixing chamber 11 and the second rich combustion gas mixing chamber 12, thereby improving safety.
[0085] As shown in Figure 3 , Figures 6-13As shown, the fire cover includes a rich combustion fire cover and a lean combustion fire cover, the rich combustion fire cover covers the rich combustion mixing chamber, and the lean combustion fire cover covers the lean combustion mixing chamber. Specifically, the rich combustion fire cover includes a first rich combustion fire cover 21, a second rich combustion fire cover 22, and a third rich combustion fire cover 23, and the lean combustion fire cover includes a first lean combustion fire cover 24 and a second lean combustion fire cover 25. From the radial outer side of the fire cover to the radial inner side of the fire cover, the first rich combustion fire cover 21, the first lean combustion fire cover 24, the second rich combustion fire cover 22, the second lean combustion fire cover 25, and the third rich combustion fire cover 23 abut in turn. The first rich combustion fire cover 21 covers the first rich combustion mixing chamber 11, the first lean combustion fire cover 24 covers the first lean combustion mixing chamber 14, the second rich combustion fire cover 22 covers the second rich combustion mixing chamber 12, the second lean combustion fire cover 25 covers the second lean combustion mixing chamber 15, and the third rich combustion fire cover 23 covers the third rich combustion mixing chamber 13. In this embodiment, on the one hand, the number of fire holes can be increased, the exchange area of the flame and the pot can be increased, and the combustion performance can be improved. On the other hand, the amount of introduced primary air can be increased by increasing the number of mixing chambers, thereby reducing the required secondary air for combustion.
[0086] As shown, Figures 1-3 the rich combustion fire holes of the rich combustion fire cover are at least partially oppositely arranged with the lean combustion fire holes of the adjacent lean combustion fire cover, so that the rich flame at the rich combustion fire hole can be counter-fired with the lean flame at the lean combustion fire hole, so that the gas combustion is more sufficient, thereby inhibiting the generation of NOx during the combustion process, reducing the emission of NOx, without additional economic cost, and without reducing the combustion efficiency.
[0087] Specifically, as shown, Figure 6 and Figure 7 the first rich combustion fire cover 21 is provided with a first rich combustion fire hole 81 on the inner circumferential wall thereof, and the inner circumferential wall of the first rich combustion fire cover 21 is inclined upward from top to bottom toward the radial inner side of the fire cover.
[0088] As shown, Figure 8 and Figure 9 the first lean combustion fire cover 24 is provided with a first lean combustion fire hole 84 on the outer circumferential wall and the inner circumferential wall thereof, the outer circumferential wall of the first lean combustion fire cover 24 is inclined upward from top to bottom toward the radial outer side of the fire cover, and the inner circumferential wall of the second lean combustion fire cover 25 is inclined upward from top to bottom toward the radial inner side of the fire cover.
[0089] As shown, Figure 10 and Figure 11 the second rich combustion fire cover 22 is provided with a second rich combustion fire hole 82 on the outer circumferential wall thereof, and the outer circumferential wall of the second rich combustion fire cover 22 is inclined upward from top to bottom toward the radial outer side of the fire cover. The second lean combustion fire cover 25 is provided with a second lean combustion fire hole 85 on the upper end wall thereof, and the upper end wall of the second lean combustion fire cover 25 is parallel to the horizontal plane.
[0090] AsFigure 12 and Figure 13 As shown, the outer peripheral wall of the third rich combustion burner cap 23 is provided with a third rich combustion burner hole 83, and the outer peripheral wall of the third rich combustion burner cap 23 is inclined radially outward from top to bottom towards the burner cap. The first rich combustion burner hole 81 and the first lean combustion burner hole 84 are arranged opposite each other, and the second rich combustion burner hole 82 and the second lean combustion burner hole 85 are arranged opposite each other to perform counter-combustion, so that the gas combustion is more complete, thereby suppressing the formation of NOx and reducing NOx emissions during the combustion process.
[0091] Furthermore, such as Figure 10 and Figure 11 As shown, the second rich combustion flame cap 22 and the second lean combustion flame cap 25 are integrally formed, which reduces the number of flame caps, facilitates installation, and improves the overall integrity of the flame caps.
[0092] like Figure 3 As shown, the projection of the burner cap along its axial direction onto the mixing chamber 1 completely overlaps with the mixing chamber 1. Because the burner can introduce more primary air, it can reduce the secondary air required for combustion. Thus, the burner cap can completely cover the mixing chamber 1 without the need for a separate secondary air supply channel. This increases the exchange area between the flame and the cookware, improves combustion performance, and facilitates the cleaning of spilled liquids.
[0093] In other alternative embodiments, the number of rich combustion mixture chambers and lean combustion mixture chambers in the mixing chamber 1 can be set to other and at least one, and the number of rich combustion mixture chambers and lean combustion mixture chambers can be the same or different.
[0094] like Figures 14-16 As shown, there are multiple nozzles 53, multiple ejector tubes 6, and multiple ejector tube mounting seats 7. The number of nozzles 53, ejector tubes 6, and ejector tube mounting seats 7 are the same and they are arranged in a one-to-one correspondence. Multiple nozzles 53 are fixed on nozzle seats 51, and multiple ejector tube mounting seats 7 are fixed on the lower end face of base 3. One end of ejector tube 6 is connected to the corresponding ejector tube mounting seat 7, and the other end of ejector tube 6 extends toward the corresponding nozzle 53.
[0095] like Figure 2 As shown, the ejector tube 6 includes a rich combustion ejector tube 61 and a lean combustion ejector tube 62. The diameter of the port of the rich combustion ejector tube 61 facing the nozzle 53 is smaller than the diameter of the port of the lean combustion ejector tube 62 facing the nozzle 53. This arrangement allows the lean combustion ejector tube 62 to introduce more primary air, thereby increasing the excess air coefficient and reducing the flame concentration.
[0096] In the description of the utility model, need understanding is, the term "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and so on indicate the orientation or positional relationship is based on the device or component in normal use process shows the orientation or positional relationship, just is for the convenience of describing the utility model and simplifying the description, and is not indicate or imply the device or component that points must have a particular orientation, constructs and operates with a particular orientation, therefore can not be understood as the restriction to the utility model.
[0097] Although the specific embodiments of the utility model are described above, those skilled in the art should understand that this is only illustrative, the protection scope of the utility model is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the utility model, but these changes and modifications all fall within the protection scope of the utility model.
Claims
1. A burner, characterized by The burner comprises: a mixing chamber having a plurality of rich combustion mixed gas cavities and a plurality of lean combustion mixed gas cavities, the rich combustion mixed gas cavities and the lean combustion mixed gas cavities being independent of each other and arranged alternately along the radial direction of the mixing chamber; a fire cover arranged at the upper end of the mixing chamber, the fire cover comprising a rich combustion fire cover and a lean combustion fire cover, the rich combustion fire cover covering the rich combustion mixed gas cavities and the lean combustion fire cover covering the lean combustion mixed gas cavities, the rich combustion fire holes of the rich combustion fire cover being arranged at least partially opposite to the lean combustion fire holes of the lean combustion fire cover adjacent thereto; wherein the projection of the fire cover on the mixing chamber along the axial direction of the fire cover completely overlaps the mixing chamber.
2. The burner of claim 1, wherein The rich combustion fire cover comprises a first rich combustion fire cover, a second rich combustion fire cover and a third rich combustion fire cover, and the lean combustion fire cover comprises a first lean combustion fire cover and a second lean combustion fire cover; from the radial outer side of the fire cover to the radial inner side of the fire cover, the first rich combustion fire cover, the first lean combustion fire cover, the second rich combustion fire cover, the second lean combustion fire cover and the third rich combustion fire cover are sequentially abutted. The rich combustion mixed gas cavities comprise a first rich combustion mixed gas cavity, a second rich combustion mixed gas cavity and a third rich combustion mixed gas cavity, and the lean combustion mixed gas cavities comprise a first lean combustion mixed gas cavity and a second lean combustion mixed gas cavity; from the radial outer side of the fire cover to the radial inner side of the fire cover, the first rich combustion mixed gas cavity, the first lean combustion mixed gas cavity, the second rich combustion mixed gas cavity, the second lean combustion mixed gas cavity and the third rich combustion mixed gas cavity are sequentially arranged. The first rich combustion fire cover covers the first rich combustion mixed gas cavity, the first lean combustion fire cover covers the first lean combustion mixed gas cavity, the second rich combustion fire cover covers the second rich combustion mixed gas cavity, the second lean combustion fire cover covers the second lean combustion mixed gas cavity, and the third rich combustion fire cover covers the third rich combustion mixed gas cavity.
3. The burner of claim 2, wherein The inner peripheral wall of the first rich combustion fire cover is provided with first rich combustion fire holes, and the inner peripheral wall of the first rich combustion fire cover is inclined downward from top to bottom towards the radial inner side of the fire cover. The outer peripheral wall and the inner peripheral wall of the first lean combustion fire cover are both provided with first lean combustion fire holes, the outer peripheral wall of the first lean combustion fire cover is inclined downward from top to bottom towards the radial outer side of the fire cover, and the inner peripheral wall of the second lean combustion fire cover is inclined downward from top to bottom towards the radial inner side of the fire cover. The outer peripheral wall of the second rich combustion fire cover is provided with second rich combustion fire holes, and the outer peripheral wall of the second rich combustion fire cover is inclined downward from top to bottom towards the radial outer side of the fire cover.
4. The burner of claim 3, wherein The upper end wall of the second lean combustion fire cover is provided with second lean combustion fire holes, and the upper end wall of the second lean combustion fire cover is parallel to the horizontal plane. The outer peripheral wall of the third rich combustion fire cover is provided with third rich combustion fire holes, and the outer peripheral wall of the third rich combustion fire cover is inclined downward from top to bottom towards the radial outer side of the fire cover.
5. The burner of claim 4, wherein The second rich combustion fire cover and the second lean combustion fire cover are integrally formed.
6. The burner of claim 2, wherein The first rich combustion mixed gas cavity and the second rich combustion mixed gas cavity are in communication.
7. The burner of claim 6, wherein The mixed gas chamber further comprises a communication channel arranged below the first lean combustion mixed gas cavity, two ends of the communication channel penetrating into the first rich combustion mixed gas cavity and the second rich combustion mixed gas cavity respectively.
8. The burner of claim 7, wherein The communication channel penetrates the lower end wall of the mixed gas chamber; the burner further comprises a base, and an upper end surface of the base is in abutment with a lower end surface of the mixed gas chamber.
9. The burner of claim 8, wherein The burner further comprises a nozzle seat, a plurality of nozzles, a plurality of injection pipes and a plurality of injection pipe mounting seats, the nozzles, the injection pipes and the injection pipe mounting seats being arranged in the same number and one-to-one correspondence. A plurality of the nozzles are fixed on the nozzle seat, and a plurality of the injection pipe mounting seats are fixed on the lower end surface of the base, one end of the injection pipe being connected with the corresponding injection pipe mounting seat, and the other end of the injection pipe extending towards the corresponding nozzle.
10. The burner of claim 9, wherein The injection pipe comprises a rich combustion injection pipe and a lean combustion injection pipe, and a port diameter of the rich combustion injection pipe towards the nozzle one end is smaller than a port diameter of the lean combustion injection pipe towards the nozzle one end.