CN221054999U - Burner and kitchen range - Google Patents

Abstract

The utility model provides a burner and a stove. The burner comprises a first gas mixing part, a second gas mixing part, an injection part and a fire cover. The first gas mixing part extends in an annular shape, and the top of the first gas mixing part is provided with a first opening; the second air mixing part is in a C shape and is coaxially overlapped with the first air mixing part in a joint and communicated way so as to form an air channel at a position between two ends of the second air mixing part corresponding to the circumferential direction; the injection part is communicated with the second gas mixing part; the fire cover is annular and covers the first opening, and a plurality of fire holes are formed in the fire cover at intervals along the circumferential direction of the fire cover. The burner can supplement a large amount of secondary air through the air channel, so that a larger proportion of fuel gas is introduced into the injection part to generate a larger heat load.

Description

Burner and kitchen range

Technical Field

The utility model relates to the technical field of kitchen appliances, in particular to a combustor and a kitchen range.

Background

Along with the gradual improvement of the living standard of people, the heat load requirement of people on the kitchen range is higher and higher, so that the food is quickly fried at high temperature through the kitchen range with higher heat load, and the cooked dish has tender and crisp texture and delicious taste. Thus, the heat load of the kitchen ranges is also higher and higher along with the demand, and the heat load is gradually increased from 4.0Kw to 4.5Kw, 5.0Kw and 5.2Kw in ten years ago.

However, most burners of the prior art have a double injection pipe structure, namely, gas and air are respectively mixed through two injection pipes and respectively introduced into an outer ring gas channel and an inner ring gas channel (or a central gas channel), and outer ring flames and inner ring flames (or central flames) are generated by ignition. In addition, there is also a three-injection pipe and a single-injection pipe structure. The furnace end of the single injection pipe structure only has one injection pipe for mixing the fuel gas and the air, and the fuel gas in the single injection pipe cannot be fully mixed with the air, or the primary air at the single injection pipe is not fully supplemented, so that the fuel gas in the single injection pipe cannot be fully consumed. The heat load of the stove is determined by factors such as the fuel consumption of the main burner, so that how to fully burn the fuel gas in the stove head is an urgent problem to be solved.

Disclosure of utility model

The present utility model is directed to solving at least one of the problems discussed above and/or other problems in the prior art.

In order to achieve the purpose of the utility model, the utility model adopts the following technical scheme:

According to one aspect of the present utility model, there is provided a burner comprising a first gas mixing section, a second gas mixing section, an injection section and a fire cover. The first gas mixing part extends in an annular shape, and the top of the first gas mixing part is provided with a first opening; the second air mixing part is in a C shape and is coaxially overlapped with the first air mixing part in a joint and communicated way so as to form an air channel at a position between two ends of the second air mixing part corresponding to the circumferential direction; the injection part is communicated with the second gas mixing part; the fire cover is annular and covers the first opening, and a plurality of fire holes are formed in the fire cover at intervals along the circumferential direction of the fire cover.

According to an embodiment of the present utility model, the air passage extends at an angle of 90 ° or more in the circumferential direction along the first air mixing portion.

According to an embodiment of the present utility model, the first air mixing portion includes a first outer wall, a first inner wall, and a first bottom wall disposed opposite to each other and corresponding to a top portion of the air channel, where the first bottom wall is connected between the first outer wall and the first inner wall, so as to enclose a first annular air mixing chamber, and the top portion and the bottom portion of the first air mixing chamber are respectively provided with the first opening and the second opening.

According to an embodiment of the present utility model, the second air mixing portion includes a second bottom wall, a second outer wall, a second inner wall, a first side wall and a second side wall, which are respectively connected to the second bottom wall, so as to enclose a second air mixing chamber with a third opening at the top, where the second outer wall is connected to the first outer wall, the second inner wall is connected to the first inner wall, the third opening is communicated with the second opening, and the second bottom wall is provided with a fourth opening.

According to one embodiment of the utility model, the connection part of the second outer wall and the first outer wall is provided with guide plates extending inwards along the circumferential direction of the second outer wall and the first outer wall, gaps are formed between the guide plates and the first side wall, the second side wall and the second inner wall respectively, and the guide plates are provided with air guide holes arranged at intervals along the circumferential direction of the guide plates.

According to an embodiment of the utility model, the second bottom wall is circular and provided with at least one first fixing leg, the bottom of the injection portion is provided with at least one second fixing leg, and the first fixing leg and the second fixing leg are configured to jointly act on a support for fixing the burner.

According to an embodiment of the present utility model, a mounting block for mounting an ignition needle is provided on the second bottom wall corresponding to the inner side of the second inner wall, and at least a part of the fire holes are provided on the inner side of the fire cover and correspond to the needle head portion of the ignition needle.

According to one embodiment of the utility model, the injection part is surrounded to form an injection cavity, the injection cavity comprises a contraction section, a throat section, a primary diffusion section and a secondary diffusion section which are distributed along the gas flow direction, one end of the contraction section, which is far away from the throat section, is connected with a nozzle mounting plate, and the secondary diffusion section is communicated with the second gas mixing part.

According to an embodiment of the utility model, the ejector is provided with a fixing plate at a position corresponding to the throat section.

According to one embodiment of the present utility model, the first air mixing portion, the second air mixing portion and the injection portion are integrally formed in one piece.

According to one embodiment of the present utility model, the fire cover includes a fire cover outer wall connected to the first outer wall, a fire cover top wall connected to the fire cover outer wall, a fire cover inner wall connected to the first inner wall, and a fire cover inclined wall extending from the fire cover top wall obliquely to the fire cover inner wall, wherein a plurality of fire holes are provided at intervals along a circumferential direction of the fire cover, and a fire igniting groove corresponding to the ignition needle is provided from the fire cover inclined wall to the fire cover outer wall.

According to another aspect of the present utility model, a cooktop is provided. The kitchen range comprises the burner and the auxiliary burner. The auxiliary burner may extend through the air passage to a central position of the second air mixing portion.

One embodiment of the present utility model has the following advantages or benefits:

The burner provided by the utility model can supplement a small amount of primary air at the front end of the injection part, and supplement a large amount of secondary air to the burner through the air channel, so that a larger proportion of fuel gas is introduced into the injection part to generate a larger heat load, and the defect that a single injection tube type burner in the prior art is limited in that only a smaller proportion of fuel gas in mixed gas is combusted, so that the heat load cannot be increased is overcome.

And the inlet of the air channel occupies more than one quarter of the angle of the section of the burner, so that the air around the second air mixing part can smoothly enter the interior of the burner, the combustion is more complete, and the CO emission is lower.

Furthermore, the design of the primary diffusion section and the secondary diffusion section of the injection part ensures that the fuel gas and the air are mixed more uniformly, and the flow speed of the mixed gas is also greatly reduced.

Drawings

The above and other features and advantages of the present utility model will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings.

Fig. 1 shows a perspective view of a burner according to an exemplary embodiment of the present utility model.

Fig. 2 shows a top view of one of the burners shown in fig. 1.

FIG. 3 shows a cross-sectional view of one of the burners shown in FIG. 1 along line A-A in FIG. 2.

Fig. 4 shows a cross-sectional view of one of the burners shown in fig. 1 along the line B-B in fig. 2.

Fig. 5 shows a cross-sectional view of one of the burners shown in fig. 1 along the line C-C in fig. 2.

FIG. 6 illustrates a partial perspective view of a cooktop of an exemplary embodiment of the present utility model.

Wherein reference numerals are as follows:

1. A first gas mixing part; 11. a first opening; 12. a first outer wall; 13. a first inner wall; 14. a first bottom wall; 15. a first air mixing chamber; 16. a second opening; 2. a second gas mixing part; 21. a second bottom wall; 211. a fourth opening; 212. a first fixed leg; 213. a mounting block; 22. a second outer wall; 221. a deflector; 2211. an air guide hole; 23. a second inner wall; 24. a first sidewall; 25. a second sidewall; 26. a third opening; 27. a second air mixing chamber; 3. an air passage; 4. an injection part; 41. a second fixed leg; 42. an ejection chamber; 421. a constriction section; 422. a throat section; 423. a primary diffusion section; 424. a secondary diffusion section; 5. a fire cover; 51. a fire hole; 52. the outer wall of the fire cover; 53. a fire cover top wall; 54. the inner wall of the fire cover; 55. a fire cover inclined wall; 56. a igniting groove; 6. an ignition needle; 7. a nozzle mounting plate; 8. an auxiliary burner.

Detailed Description

Example embodiments will now be described more fully with reference to the accompanying drawings. However, the exemplary embodiments can be embodied in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the example embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and thus detailed descriptions thereof will be omitted.

The terms "a," "an," "the," and "said" are used to indicate the presence of one or more elements/components/etc.; the terms "comprising" and "having" are intended to be inclusive and mean that there may be additional elements/components/etc. in addition to the listed elements/components/etc.

As to the background art, in the usual burner with a double-injection pipe structure or a triple-injection pipe structure, because the double-injection pipe structure and the triple-injection pipe structure are in a big fire mode, the mixed gas of the fuel gas and the air simultaneously flows through more than two injection pipes, so that the flow area of the mixed gas is larger, and the larger heat load is easy to achieve. In the case of a burner with a single injection pipe structure, the burner is limited by the flow area of the mixed gas and the proportion of the fuel gas which is burned simultaneously, so that a large heat load is difficult to achieve.

The burner provided by the utility model is of a single injection pipe structure, and simultaneously forms a combined burner together with the other auxiliary burner 8 which is smaller and can extend into the middle of the burner from the air channel 3, a small amount of primary air is supplemented at the front end of the injection part 4 of the burner, and a large amount of secondary air is supplemented to the burner through the air channel 3, so that a larger proportion of fuel gas is introduced into the injection part 4 to generate a larger heat load, and the defect that the single injection pipe type burner in the prior art is limited in that only a smaller proportion of fuel gas is combusted in mixed gas, so that the heat load cannot be increased is overcome.

Fig. 1 to 5 show a burner according to an embodiment of the present utility model. As shown in fig. 1 and 2, the burner according to this embodiment may include a first gas mixing portion 1, a second gas mixing portion 2, an injection portion 4, and a flame cover 5. The first air mixing part 1 extends in a ring shape in a first plane (a transverse plane or a horizontal plane as shown in fig. 1), and the top of the first air mixing part 1 is provided with a first opening 11. The second air mixing part 2 also extends in a C-shape in a first plane (a transverse plane or a horizontal plane as shown in fig. 1), and when the second air mixing part 2 is coaxially disposed with the first air mixing part and is overlapped and joined to the bottom of the first air mixing part 1 and communicates with the first air mixing part 1, an air passage 3 may be formed at a position of the second air mixing part 2 corresponding to between both end portions in the circumferential direction thereof. The injection portion 4 is communicated with the second gas mixing portion 2, one end, far away from the second gas mixing portion 2, of the injection portion 4 is connected with a nozzle used for being communicated with an indoor gas pipeline, and small amount of primary air is supplemented for gas entering the injection portion 4 through the nozzle, so that mixing of the gas and small amount of air is conducted in the injection portion 4. The annular fire cover 5 may completely cover the top of the first gas mixing portion 1, and a plurality of fire holes 51 are provided at intervals along the axial direction of the fire cover 5, so that the gas mixture of the first gas mixing portion 1 is ignited when reaching the fire holes 51 through the first opening 11. The air entering the fire hole 51 from the air passage 3 supplements the mixture with a sufficient amount of secondary air, so that the burner with a single injection pipe structure can obtain a large heat load.

According to a preferred embodiment of the air passage 3, as shown in fig. 1, the extending angle of the air passage 3 in the circumferential direction along the first air mixing portion 1 is 90 ° or more, so that the air around the second air mixing portion 2 can smoothly enter the inside of the burner by more than one fourth of the angle of the cross section of the burner occupied by the inlet of the air passage 3, and further flows to each fire hole 51 on the fire cover 5, particularly the fire hole 51 on the inner side wall of the fire cover 5, to provide sufficient secondary air for the combustion of the mixture at the fire hole 51, so that the combustion is more sufficient and the CO emission is lower.

According to an exemplary embodiment of the first gas mixing section 1, as shown in fig. 3, the first gas mixing section 1 comprises a first outer wall 12, a first inner wall 13 and a first bottom wall 14, which are arranged opposite to each other. The first bottom wall 14 is connected between the first outer wall 12 and the first inner wall 13 and is provided corresponding to the top of the air passage 3, so that a second opening 16 is formed between the first outer wall 12 and the first inner wall 13 at a position where the first bottom wall 14 is not provided. The top of the first outer wall 12 and the top of the first inner wall 13 are spaced apart from each other by a distance so as to form a first opening 11, such that a first mixing chamber 15 is formed between the first outer wall 12 and the first inner wall 13.

According to one exemplary embodiment of the second gas mixing section 2, as shown in fig. 3 and 4, the second gas mixing section 2 comprises a second bottom wall 21, a second outer wall 22, a second inner wall 23, a first side wall 24 and a second side wall 25. The second bottom wall 21 is provided at the bottom of the second air mixing section 2, and is provided with a fourth opening 211. The second outer wall 22 and the second inner wall 23 are respectively provided with a ring shape with a notch (i.e. are in a shape of C) and are arranged at intervals, wherein the second outer wall 22 is connected with the first outer wall 12, and the second inner wall 23 is connected with the first inner wall 13. The first side wall 24 and the second side wall 25 are provided at both end portions of the second outer wall 22 in the circumferential direction thereof, respectively, and extend inward to the second inner wall 23 in the radial direction of the second air mixing portion 2, thereby forming the air passage 3 between the first side wall 24 and the second side wall 25. So that a third opening 26 is formed between the top of the second outer wall 22, the top of the second inner wall 23, the top of the first side wall 24 and the top of the second side wall 25, the third opening 26 and the second opening 16 corresponding and communicating. The second bottom wall 21 is provided with a fourth opening 211 for communication with the injection portion 4. In a further preferred embodiment, the first gas mixing section 1 and the second gas mixing section 2 are integrally formed in one piece by some process, for example by die casting or integral casting of a metallic material.

In the above embodiment, in order to enable the mixture gas entering the second gas mixing portion 2 through the fourth opening 211 to be uniformly distributed in the circumferential direction of the second gas mixing portion 2, the connection portion between the second outer wall 22 and the first outer wall 12 is provided with the baffle 221 extending inward along the circumferential directions of the two. As shown in fig. 3 to 5, two ends of the baffle 221 in the circumferential direction have a certain gap with the first sidewall 24 and the second sidewall 25, respectively, the outer end of the baffle 221 is connected to the second outer wall 22, the inner end has a certain gap with the second inner wall 23, and a plurality of air guide holes 2211 are formed in the baffle 221 along the circumferential direction at intervals. After the mixed gas flows into the second mixed gas cavity 27 from the fourth opening 211, the mixed gas guided by the guide plate 221 can uniformly flow into the first mixed gas cavity 15, and further mixed in the first mixed gas cavity 15, so that the pressure of the mixed gas is more uniform, and then flows into each fire hole 51 on the fire cover 5, so that the flame at the fire cover 5 is more uniform. In other embodiments, the baffle 221 may be connected to the second inner wall 23 with a gap between the baffle and the second outer wall 22.

In order to support the first air mixing part 1 and the second air mixing part 2 on the bottom shell of the kitchen range and further keep the balance of the burner from shaking, as shown in fig. 1, the second bottom wall 21 is circular, and at least one first fixing leg 212 extending toward one end of the second bottom wall 21 away from the fire cover 5 is provided at intervals at the bottom of the second bottom wall 21. At least one second fastening leg 41 is provided at the bottom of the injection part 4, the second fastening leg 41 and the first fastening leg 212 being configured to cooperate with the support fastening of the burner. For example, the burner is fixed to the bottom shell of the hob.

According to a further exemplary embodiment of the second air-mixing portion 2, as shown in fig. 1 to 5, the second bottom wall 21 of the second air-mixing portion 2 is provided with a mounting block 213 for mounting the ignition needle 6 corresponding to the inside of the second inner wall 23, at least a part of the fire holes 51 is provided inside the fire cover 5, and at least a part of the fire holes 51 corresponds to the needle head portion of the ignition needle 6. In other specific embodiments, the mounting block 213 may also be disposed on the outside of the second bottom wall 21 corresponding to the second inner wall 23, such that at least a portion of the fire hole 51 may also be disposed on the outside of the fire cover 5 and corresponding to the needle head portion of the ignition needle 6.

According to an exemplary embodiment of the injection portion 4, as shown in fig. 5, the injection portion 4 encloses an injection cavity 42, and the injection cavity 42 may include a constriction 421, a throat 422, a primary diffuser 423, and a secondary diffuser 424 distributed along the gas flow direction (right-to-left direction in fig. 3). A nozzle mounting plate 7 is provided at the end of the constriction 421 remote from the throat 422 for mounting a nozzle, and a part of air is sucked by negative pressure to form a mixture when gas enters the constriction 421 from the indoor gas supply line. The secondary diffuser 424 is a cavity structure larger than the primary expansion section and communicates with the fourth opening 211 of the second air mixing section 2. When the initial gas enters the constriction 421, the cross-sectional area of the constriction 421 gradually decreases, and the gas jet forms a entrainment flow, and a negative pressure region occurs due to the high velocity of the gas flow, so that a part of air is absorbed and enters the constriction 421 from the nozzle together with the gas to generate a mixture. After the mixed gas enters the throat section 422, the cross-sectional area of the throat section 422 is kept unchanged along with the flow of the gas, so that the mixed gas can exchange kinetic energy in the throat section 422, and the velocity field of the mixed gas is gradually and uniformly distributed in the flowing process. Then the mixed gas enters the primary diffusion section 423, the pressure is increased due to the reduction of the flow velocity, and part of dynamic pressure of the mixed gas becomes static pressure, so that the pressure of the mixed gas is higher than the pressure of the injection fluid just entering the contraction section 421, the flow velocity of the mixed gas is reduced, and the gas and the air are uniformly mixed at the moment. After the mixture enters the secondary diffuser 424, the static pressure further increases, and the flow rate of the mixture further decreases, at which time the mixture is more uniformly mixed. The design of the primary diffusion section 423 and the secondary diffusion section 424 ensures that the fuel gas and the air are mixed more uniformly, and the flow speed of the mixed gas is also greatly reduced. It will be appreciated that the pressure of the fluid acting perpendicularly on the wall is referred to as static pressure and that the pressure resulting from the velocity as the mixture flows within the ejector portion 4 of the pipe structure is referred to as dynamic pressure.

Preferably, the injection part 4 and the second gas mixing part 2 are integrally formed into one piece by some process, for example, by die casting or integral casting of a metal material. The ejector 4 is provided with a second fixing leg 41 at a position corresponding to the throat section 422, and cooperates with the two first fixing legs 212 provided at an interval on the second bottom wall 21 to form a tripod shape for supporting and fixing the burner.

According to an exemplary embodiment of the fire cover 5, as shown in fig. 3, the fire cover 5 includes a fire cover outer wall 52 connected to the first outer wall 12, respectively, a fire cover top wall 53 connected to the fire cover outer wall 52, a fire cover inner wall 54 connected to the first inner wall 13, and a fire cover inclined wall 55 extending from the fire cover top wall 53 obliquely to the fire cover inner wall 54, the fire cover inclined wall 55 and the fire cover outer wall 52 are provided with a plurality of fire holes 51 at intervals along the circumferential direction of the fire cover 5, respectively, so that an outer ring flame and an inner ring flame can be formed at the outer circumference of the fire cover 5 and the inner circumference of the fire cover 5, respectively. And a igniting groove 56 corresponding to the ignition needle 6 is provided in the ignition cover top wall 53, the igniting groove 56 extends from the ignition cover inclined wall 55 to the ignition cover outer wall 52, and the mixture at the ignition hole 51 on the ignition cover inclined wall 55 or the ignition cover outer wall 52 can be ignited, regardless of whether the needle head portion of the ignition needle 6 is provided inside or outside the ignition cover 5, and the mixture at the ignition hole 51 on the ignition cover outer wall 52 or the ignition cover inclined wall 55 is ignited by the igniting groove 56.

The utility model also provides a kitchen range. Fig. 6 shows a partial perspective view of the hob. The hob comprises a burner as described above and an auxiliary burner 8. The auxiliary burner 8 can extend through the air passage 3 to a central position of the second air mixing section 2.

In embodiments of the present utility model, the term "plurality" refers to two or more, unless explicitly defined otherwise. The terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly attached, detachably attached, or integrally attached. The specific meaning of the above terms in the embodiments of the present utility model will be understood by those of ordinary skill in the art according to specific circumstances.

In the description of the embodiments of the present utility model, it should be understood that the directions or positional relationships indicated by the terms "upper", "lower", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience in describing the embodiments of the present utility model and to simplify the description, and do not indicate or imply that the devices or units referred to must have a specific direction, be configured and operated in a specific direction, and thus should not be construed as limiting the embodiments of the present utility model.

In the description of the present specification, the terms "one embodiment," "a preferred embodiment," and the like, mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the embodiments of the present utility model. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The above is only a preferred embodiment of the present utility model and is not intended to limit the embodiment of the present utility model, and various modifications and variations can be made to the embodiment of the present utility model by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the embodiments of the present utility model should be included in the protection scope of the embodiments of the present utility model.

Claims (11)

1. A burner, comprising:

The first gas mixing part (1), the first gas mixing part (1) extends in a ring shape and is provided with a first opening (11) at the top;

The second air mixing part (2), the second air mixing part (2) is in a shape of C and is coaxially overlapped with the first air mixing part (1) to be connected and communicated, so that an air channel (3) is formed at a position between two ends of the second air mixing part (2) corresponding to the circumferential direction;

The injection part (4) is communicated with the second gas mixing part (2); and

The fire cover (5), fire cover (5) are cyclic annular and cover locate first opening (11) department, fire cover (5) are provided with a plurality of fire holes (51) along its circumference interval.

2. Burner according to claim 1, wherein the extension angle of the air passage (3) in the circumferential direction along the first air mixing portion (1) is 90 ° or more.

3. Burner according to claim 1, characterized in that the first air mixing section (1) comprises a first outer wall (12), a first inner wall (13) and a first bottom wall (14) arranged opposite to each other and corresponding to the top of the air channel (3), the first bottom wall (14) being connected between the first outer wall (12) and the first inner wall (13) so as to enclose a first air mixing chamber (15) forming a ring shape, the top and bottom of the first air mixing chamber (15) being provided with the first opening (11) and the second opening (16), respectively.

4. A burner according to claim 3, wherein the second air mixing portion (2) comprises a second bottom wall (21), a second outer wall (22), a second inner wall (23), a first side wall (24) and a second side wall (25) respectively connected to the second bottom wall (21) so as to enclose a second air mixing chamber (27) having a third opening (26) at the top, the second outer wall (22) being connected to the first outer wall (12), the second inner wall (23) being connected to the first inner wall (13), the third opening (26) being in communication with the second opening (16), the second bottom wall (21) being provided with a fourth opening (211).

5. The burner according to claim 4, wherein the connection between the second outer wall (22) and the first outer wall (12) is provided with an inwardly extending guide plate (221) along the circumferential direction of the second outer wall and the first outer wall, gaps are respectively arranged between the guide plate (221) and the first side wall (24), between the guide plate (221) and the second side wall (25) and between the guide plate and the second inner wall (23), and air guide holes (2211) are formed in the guide plate (221) at intervals along the circumferential direction of the guide plate.

6. Burner according to claim 4, characterized in that said second bottom wall (21) is circular and is provided with at least one first fixing leg (212), the bottom of said injection portion (4) being provided with at least one second fixing leg (41), said first fixing leg (212) and said second fixing leg (41) being configured to cooperate with a supporting fixation of said burner.

7. Burner according to claim 4, characterized in that said second bottom wall (21) is provided with a mounting block (213) for mounting an ignition needle (6) in correspondence of the inside of said second inner wall (23), at least a portion of said fire holes (51) being provided in correspondence of the needle head portion of said ignition needle (6) in the inside of said fire cover (5).

8. The burner according to claim 1, wherein the injection part (4) encloses and forms an injection cavity (42), the injection cavity (42) comprises a contraction section (421), a throat section (422), a primary diffusion section (423) and a secondary diffusion section (424) which are distributed along the gas flow direction, one end of the contraction section (421) away from the throat section (422) is connected with a nozzle mounting plate (7), and the secondary diffusion section (424) is communicated with the second gas mixing part (2).

9. Burner according to any one of claims 1 to 8, wherein the first gas mixing section (1), the second gas mixing section (2) and the injection section (4) are integrally formed in one piece.

10. Burner according to any one of claims 3 to 7, wherein the fire cover (5) comprises a fire cover outer wall (52) connected to the first outer wall (12), a fire cover top wall (53) connected to the fire cover outer wall (52), a fire cover inner wall (54) connected to the first inner wall (13), and a fire cover inclined wall (55) extending from the fire cover top wall (53) to the fire cover inner wall (54), the fire cover inclined wall (55) and the fire cover outer wall (52) being provided with a plurality of fire holes (51) at intervals along the circumferential direction of the fire cover (5), respectively, and a firing slot (56) corresponding to a firing pin (6) being provided from the fire cover inclined wall (55) to the fire cover outer wall (52).

11. A cooktop, comprising:

the burner of any one of claims 1 to 10; and

-An auxiliary burner (8), which auxiliary burner (8) can extend through the air channel (3) to a central position of the second air mixing section (2).