Combustor and gas stove

Abstract

This utility model belongs to the field of gas stove technology, and discloses a burner and a gas stove. The burner base has an annular groove with a concave extension groove. One end of the extension groove penetrates the base to form a connecting port. The burner also includes a gas equalization plate and an ejector cover plate. The gas equalization plate is disposed in the base to separate the annular groove into a first mixing chamber and a second mixing chamber arranged vertically. The gas equalization plate has a flow hole to connect the first mixing chamber and the second mixing chamber. An ejector tube is disposed at the bottom of the base, and one end is connected to the connecting port. The ejector cover plate is connected to the base and covers the extension groove to form an extension pipe. The extension pipe connects to the ejector tube. The end of the ejector cover plate away from the connecting port is inclined towards the gas equalization plate. The burner of this utility model can improve the uniformity of gas and air mixing, which is beneficial to improving the stability and safety of the combustion process, effectively improving the thermal efficiency of the gas stove, and extending the service life of the gas stove.

Description

Technical Field

[0001] This utility model relates to the field of gas stove technology, and in particular to burners and gas stoves. Background Technology

[0002] Gas stoves are kitchen appliances that use direct flame heating through the combustion of gaseous fuels. Top-intake burners are combustion systems specifically designed for gas stoves. The air required for combustion enters entirely from above the cooktop panel, eliminating the need for oxygen supply from the bottom. This offers advantages such as high safety and ease of cleaning and maintenance. Top-intake burners utilize an injector to accelerate gas flow and draw in secondary air for mixing. To improve safety and space utilization, some existing technologies conceal the injector beneath the premixing chamber in the base. However, the limited size of the injector can lead to uneven gas-air mixing, compromising the stability and safety of the combustion process. This can result in abnormal combustion conditions such as flame lift-off, backfire, or deflagration, causing ignition difficulties, reduced thermal efficiency, and accelerated wear and tear on critical components like the nozzle and injector over time. Utility Model Content

[0003] One objective of this invention is to provide a burner that can solve the problems of limited ejector tube size, uneven mixing of gas and air, abnormal combustion, difficulty in ignition, reduced thermal efficiency, and accelerated wear of key components caused by existing top-inlet burners.

[0004] To achieve this objective, the present invention adopts the following technical solution:

[0005] A burner is provided, including a base and an ejector tube. The base has an annular groove with a concave extension groove. One end of the extension groove passes through the base to form a communication port. The burner also includes a gas equalization plate and an ejector cover plate. The gas equalization plate is disposed in the base to separate the annular groove into a first mixing chamber and a second mixing chamber arranged vertically. The gas equalization plate has a flow hole to connect the first mixing chamber and the second mixing chamber. The ejector tube is disposed at the bottom of the base and one end is connected to the communication port. The ejector cover plate is connected to the base and covers the extension groove to form an extension pipe. The extension pipe connects to the ejector tube. The end of the ejector cover plate away from the communication port is inclined towards the gas equalization plate.

[0006] In one embodiment, the bottom of the annular groove is recessed to form the extension groove, the extension groove including a lifting section, the bottom of the lifting section being inclined toward the end near the communication opening in a direction away from the bottom of the annular groove.

[0007] In one embodiment, the ejector cover includes an interconnected mounting section and an extension section. The mounting section is detachably connected to the base, and the extension section covers at least a portion of the lifting section. The end of the extension section away from the mounting section is inclined toward the direction close to the air distribution plate.

[0008] In one embodiment, the base includes a base plate, an inner side wall and an outer side wall that are coaxially arranged and interlocked, the base plate being connected to the inner side wall and the outer side wall to form the annular groove, the extension groove being formed in the base plate, the extension section being embedded between the inner side wall and the outer side wall, and the extension groove, the extension section, and a portion of the inner side wall and a portion of the outer side wall enclosing each other to form a portion of the extension pipe.

[0009] In one embodiment, the extension pipe includes a diffuser pipe disposed between the connecting port and the lifting section, the two ends of the diffuser pipe being a large-diameter end and a small-diameter end, the large-diameter end being connected to the lifting section and the small-diameter end being connected to the connecting port;

[0010] The extension groove also includes a diffuser section, one end of which is connected to the lifting section and the other end of which is connected to the connecting port. The installation section is placed over the diffuser section to form the diffuser pipe.

[0011] In one embodiment, the ejector cover has a support end plate at its end away from the communication port, the upper surface of the support end plate extending in a horizontal direction, the support end plate being used to support the air distribution plate.

[0012] In one embodiment, the support end plate and the air distribution plate are detachably connected; and / or,

[0013] One of the supporting end plate and the air distribution plate has a positioning hole, and the other has a positioning protrusion, which is inserted into the positioning hole.

[0014] In one embodiment, the gas equalization plate has a plurality of flow holes, which are evenly spaced on the gas equalization plate.

[0015] In one embodiment, the annular groove has two extension grooves, the burner includes two ejector tubes and two ejector covers, the two ejector covers and the two extension grooves correspond one-to-one to form two extension pipes, the two extension pipes are respectively connected to the two ejector tubes, the two ejector tubes are symmetrically arranged with respect to the center of the base, at least part of the extension pipes extend arc-shaped around the center of the base, and the flow direction of the airflow after passing through the two extension pipes is the same.

[0016] Another objective of this invention is to provide a gas stove with the aforementioned burner that can solve the problem of uneven gas-air mixing caused by the limited size of the injector tube in existing top-intake burners, avoid problems such as abnormal combustion and difficulty in ignition, improve the thermal efficiency of the gas stove, and reduce the wear and tear on key components.

[0017] To achieve this objective, the present invention employs the following technical solution in another aspect:

[0018] Gas stoves are provided, including burners as described above.

[0019] The beneficial effects of this utility model are:

[0020] The burner provided by this utility model has an annular groove in its base, and a concave extension groove inside the annular groove. One end of the extension groove penetrates the base to form a communication port. An ejector tube is located at the bottom of the base, with one end connected to the communication port. The ejector tube is hidden below the base, reducing its space occupation and facilitating the miniaturization of the burner. The burner also includes a gas equalization plate and an ejector cover plate. The gas equalization plate is located inside the base to separate the annular groove into a first mixing chamber and a second mixing chamber, which are arranged vertically. A flow hole is formed on the gas equalization plate to connect the first and second mixing chambers. The upper first mixing chamber is connected to the outside, introducing supplemental secondary air. An ejector cover is connected to the base and covers the extension groove to form an extension pipe. The extension pipe connects to the ejector tube, extending the ejection path. Gas in the ejector tube enters the extension pipe through the connecting port. The relatively enclosed space facilitates further mixing of the fuel gas and air, improving the uniformity of the mixture. Moreover, compared to the second mixing chamber, the space in the extension pipe is relatively small, resulting in a slower flow rate of the mixed gas. The extension pipe has a pressurizing effect; the pressurized mixed gas enters the second mixing chamber through the extension pipe, where it undergoes further mixing. The end of the ejector cover away from the connecting port is inclined towards the gas equalization plate, guiding the mixed gas in the second mixing chamber through the gas equalization plate to the upper first mixing chamber. Flow holes on the gas equalization plate divert the mixed gas, facilitating further mixing within the first mixing chamber and improving the uniformity of the fuel gas and air mixture. During the aforementioned flow process, the gas undergoes multiple mixing processes. The well-mixed gas mixture helps to improve the stability and safety of the combustion process, reduces abnormal combustion conditions such as flame lift-off, backfire, or deflagration, effectively improves thermal efficiency, and reduces the wear rate of key components such as nozzles and ejector tubes after long-term use.

[0021] The gas stove provided by this utility model includes the aforementioned burner. The burner's ejector cover is connected to the base and covers the extension groove to form an extension pipe. This extension pipe lengthens the ejection path, and the relatively enclosed space facilitates further mixing of gas and air, improving the uniformity of the gas mixture. Furthermore, the extension pipe has a pressurizing effect; the pressurized gas mixture enters the second mixing chamber through the extension pipe, where it undergoes further mixing. The inclined ejector cover guides the gas mixture in the second mixing chamber through a gas equalization plate to the upper first mixing chamber. The flow holes on the gas equalization plate divert the gas mixture, facilitating further mixing within the first mixing chamber and improving the uniformity of the gas-air mixture. This fully mixed gas improves the stability and safety of the combustion process, effectively increasing the gas stove's thermal efficiency and lifespan. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the burner provided in an embodiment of the present invention;

[0023] Figure 2 This is a structural disassembly diagram of the burner provided in this embodiment of the utility model;

[0024] Figure 3 This is a top view of the burner provided in this embodiment of the utility model;

[0025] Figure 4 yes Figure 3 Cross-sectional view of the structure along the AA direction;

[0026] Figure 5 This is a schematic diagram of the base provided in an embodiment of the present invention from a certain perspective;

[0027] Figure 6 This is a structural schematic diagram of the base provided in an embodiment of the present invention from another perspective.

[0028] In the picture:

[0029] 1. Base; 11. Annular groove; 111. First mixing chamber; 112. Second mixing chamber; 12. Extension groove; 121. Lifting section; 122. Diffusion section; 13. Inner wall; 14. Outer wall; 15. Base plate; 16. Connecting port;

[0030] 2. Injector tube; 3. Gas distribution plate; 31. Flow hole; 32. Positioning hole;

[0031] 4. Injector cover; 41. Installation section; 42. Extension section; 43. Support end plate; 44. Positioning protrusion; 5. Injector cover. Detailed Implementation

[0032] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0033] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this utility model and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions. Moreover, "above," "on top of," and "over" the first feature in relation to the second feature includes the first feature directly above and diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "under," and "below" the first feature in relation to the second feature includes the first feature directly below and diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0034] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0035] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0036] like Figures 1 to 4 As shown, this embodiment first provides a burner, which includes a base 1 and an injector tube 2. The mixture of fuel gas and primary air enters the injector tube 2 through a nozzle.

[0037] An annular groove 11 is provided inside the base 1, and an inwardly recessed extension groove 12 is provided inside the annular groove 11. One end of the extension groove 12 penetrates the base 1 to form a connecting port 16. An ejector tube 2 is provided at the bottom of the base 1, and one end is connected to the connecting port 16. The ejector tube 2 is hidden below the base 1, reducing the space occupied and facilitating the miniaturization of the burner. The burner also includes a gas equalization plate 3 and an ejector cover plate 4. The gas equalization plate 3 is provided inside the base 1 to separate the annular groove 11 into a first mixing chamber 111 and a second mixing chamber 112 arranged vertically. A flow hole 31 is provided on the gas equalization plate 3 to connect the first mixing chamber 111 and the second mixing chamber 112. The upper first mixing chamber 111 is connected to the outside to introduce supplemental secondary air. An ejector cover 4 is connected to the base 1 and covers the extension groove 12 to form an extension pipe. The extension pipe connects to the ejector tube 2, extending the ejection path. Gas in the ejector tube 2 enters the extension pipe through the connecting port 16. The relatively enclosed space facilitates further mixing of the gas and air, improving the uniformity of the mixture. Moreover, compared to the second mixing chamber 112, the space inside the extension pipe is relatively small, resulting in a slower flow rate of the mixed gas. The extension pipe has a pressurizing effect, and the pressurized mixed gas enters the second mixing chamber 112 through the extension pipe, where it undergoes further mixing. The end of the ejector cover 4 away from the connecting port 16 is inclined towards the gas equalization plate 3, guiding the mixed gas in the second mixing chamber 112 through the gas equalization plate 3 to flow into the upper first mixing chamber 111. The flow holes 31 on the gas equalization plate 3 divert the mixed gas, facilitating further mixing of the mixed gas in the first mixing chamber 111 and improving the uniformity of the gas and air mixture. During the aforementioned flow process, the gas undergoes multiple mixing processes. The well-mixed gas mixture helps to improve the stability and safety of the combustion process, reduces abnormal combustion conditions such as flame lift-off, backfire, or deflagration, effectively improves thermal efficiency, and reduces the wear rate of key components such as nozzles and ejector tubes after long-term use.

[0038] The burner also includes a flame cap 5 covering the base 1, which closes the annular groove 11 and introduces secondary air into the first mixing chamber 111. (Refer to...) Figure 4 .

[0039] In one embodiment, the ejector tube 2 is arranged horizontally along its axis. The bottom of the annular groove 11 is recessed to form an extension groove 12, which includes a lifting section 121, such as... Figure 5 As shown. The bottom of the lifting section 121, near the connecting port 16, is inclined away from the bottom of the annular groove 11. The inclined lifting section 121 has its lower end connected to the ejector tube 2 and its upper end extending to connect to the annular groove 11. The bottom of the lifting section 121 is curved, which improves the flow guiding performance and reduces gas flow resistance.

[0040] The ejector cover 4 includes an interconnected mounting section 41 and an extension section 42. The mounting section 41 is detachably connected to the base 1. The extension section 42 covers at least a portion of the lifting section 121. The end of the extension section 42 away from the mounting section 41 is inclined towards the gas equalization plate 3. In one embodiment, the extension section 42 covers a portion of the lifting section 121 without obstructing the area above the connection between the lifting section 121 and the annular groove 11. Some of the mixed gas flows along the extension section 42, and at the end of the extension section 42, it can flow more smoothly upward to participate in remixing within the second mixing chamber 112.

[0041] Specifically, the base 1 includes a base plate 15, an inner wall 13 and an outer wall 14 coaxially arranged and interlocked, with the base plate 15 connected to the inner wall 13 and the outer wall 14 to form an annular groove 11. An extension groove 12 is formed in the base plate 15, and an extension section 42 is embedded between the inner wall 13 and the outer wall 14. The extension groove 12, the extension section 42, and a portion of the inner wall 13 and a portion of the outer wall 14 enclose a partial extension pipe. The two sides of the extension section 42 abut against the inner wall 13 and the outer wall 14 respectively, reducing the gap between the extension section 42 and the inner wall 13 and the outer wall 14, improving the sealing performance of the extension pipe, and ensuring the pressurization and mixing effect of the extension pipe.

[0042] In one embodiment, the extension pipe includes a diffuser pipe disposed between the connecting port 16 and the lifting section 121. The two ends of the diffuser pipe are a large-diameter end and a small-diameter end, respectively. The large-diameter end is connected to the lifting section 121, and the small-diameter end is connected to the connecting port 16. The mixed gas in the ejector tube 2 enters the small-diameter end through the connecting port 16. During the flow in the diffuser pipe, since the inner diameter of the diffuser pipe changes, the cross-sectional area of ​​the large-diameter end is larger than that of the small-diameter end, the flow velocity of the mixed gas slows down, and the dynamic pressure becomes static pressure, which is conducive to further mixing of gas and air. In order to form a diffuser pipe, the extension groove 12 also includes a diffuser section 122. One end of the diffuser section 122 is connected to the lifting section 121, and the other end is connected to the connecting port 16. The mounting section 41 is covered on the diffuser section 122 to form a diffuser pipe.

[0043] The installation section 41 has a groove to form one half of the diffuser pipe, and the diffuser section 122 forms the other half of the diffuser pipe. The installation section 41 and the diffuser section 122 together form the diffuser pipe.

[0044] The ejector cover 4 has a support end plate 43 at its end away from the communication port 16. The upper surface of the support end plate 43 extends horizontally and is used to support the air distribution plate 3, such as... Figure 4 As shown. The air distribution plate 3 is set on the support end plate 43. The upper surface of the support end plate 43 provides stable support for the air distribution plate 3, maintains the positional stability of the air distribution plate 3, and avoids unstable installation such as tilting of the air distribution plate 3.

[0045] In one embodiment, the support end plate 43 and the gas equalization plate 3 are detachably connected, and the gas equalization plate 3 can be removed from the ejector cover plate 4 for easy maintenance.

[0046] For example, in one embodiment, one of the support end plate 43 and the air distribution plate 3 has a positioning hole 32, and the other has a positioning protrusion 44, which is inserted into the positioning hole 32. Figure 2 As shown in the figure, the upper surface of the support end plate 43 is provided with a positioning protrusion 44, and the air distribution plate 3 is provided with a corresponding positioning hole 32. The air distribution plate 3 is placed on the support end plate 43, and the positioning protrusion 44 is inserted into the positioning hole 32, so that the air distribution plate 3 can be installed. The installation and disassembly are relatively convenient.

[0047] To improve the uniformity of the gas-air mixture, the gas distribution plate 3 has multiple flow holes 31, which are evenly spaced on the gas distribution plate 3. In this embodiment, the diameter and number of flow holes 31 are not limited, and can be specifically set according to the heat load and operating level of the burner.

[0048] In one embodiment, such as Figure 5 and Figure 6 As shown, the annular groove 11 has two extension grooves 12. The burner includes two ejector tubes 2 and two ejector cover plates 4. The two ejector cover plates 4 and the two extension grooves 12 correspond one-to-one to form two extension pipes. The two extension pipes are connected to the two ejector tubes 2 respectively. The two ejector tubes 2 are symmetrically arranged with respect to the center of the base 1. At least part of the extension pipes extends in an arc around the center of the base 1. The airflow direction after passing through the two extension pipes is the same. The arrangement of the two ejector tubes 2 and the two extension pipes can increase the intake airflow, thereby improving the thermal efficiency. After the airflow exits through the extension pipes, it flows tangentially along the extension pipes and rotates along the annular groove 11. The two airflows formed by the two extension pipes have the same rotation direction and flow clockwise or counterclockwise, avoiding airflow blockage caused by gas convection and affecting the smoothness of the intake.

[0049] Two ejector covers 4 extend towards the upper gas equalization plate 3, providing two supports for the gas equalization plate 3 through their respective support end plates 43, making the gas equalization plate 3 more stable and preventing tilting during use. Moreover, since the support end plates 43 and the gas equalization plate 3 abut against each other, the two ejector covers 4 divide the lower second mixing chamber 112 into two relatively closed areas. The gas flowing out of the two extended pipes flows in their respective spaces and flows towards the upper gas equalization plate 3, reducing mutual airflow interference and preventing gas turbulence and collision from affecting combustion stability.

[0050] This utility model embodiment further provides a gas stove, which includes the burner in any of the above embodiments. The burner's ejector cover 4 is connected to the base 1 and covers the extension groove 12 to form an extension pipe. The extension pipe connects to the ejector tube 2, extending the ejection path. Gas in the ejector tube 2 enters the extension pipe through the connecting port 16. The relatively enclosed space facilitates further mixing of gas and air, improving the uniformity of the mixed gas. Moreover, compared to the second mixing chamber 112, the space inside the extension pipe is relatively small, resulting in a slower flow rate of the mixed gas. The extension pipe has a pressurizing effect; the pressurized mixed gas enters the second mixing chamber 112 through the extension pipe, forming further mixing. The end of the ejector cover 4 away from the connecting port 16 is inclined towards the gas equalization plate 3, guiding the mixed gas in the second mixing chamber 112 to flow through the gas equalization plate 3 to the upper first mixing chamber 111. The flow holes 31 on the gas distribution plate 3 divert the mixed gas, facilitating further mixing of the gas in the first mixing chamber 111 and improving the uniformity of the gas-air mixture. A well-mixed gas mixture enhances the stability and safety of the combustion process, reducing abnormal combustion conditions such as flame lift-off, backfire, or deflagration. This effectively improves the thermal efficiency of the gas stove and extends its service life.

[0051] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make various obvious changes, readjustments, and substitutions without departing from the protection scope of this utility model. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. Burner comprising a base (1) and a lance (2), said base (1) being provided with an annular groove (11) inside it, characterized in that, The annular groove (11) has a concave extension groove (12) inside. One end of the extension groove (12) penetrates the base (1) to form a communication port (16). The burner also includes a gas equalization plate (3) and an ejector cover plate (4). The gas equalization plate (3) is disposed in the base (1) to separate the annular groove (11) into a first mixing chamber (111) and a second mixing chamber (112) arranged vertically. The gas equalization plate (3) has a flow hole (31) to connect the first mixing chamber (111) and the second mixing chamber (112). A first mixing chamber (111) and a second mixing chamber (112) are provided. The ejector tube (2) is disposed at the bottom of the base (1) and one end is connected to the connecting port (16). The ejector cover plate (4) is connected to the base (1) and covers the extension groove (12) to form an extension pipe. The extension pipe is connected to the ejector tube (2). The end of the ejector cover plate (4) away from the connecting port (16) is inclined toward the direction close to the gas equalization plate (3).

2. The burner of claim 1, wherein The bottom of the annular groove (11) is recessed to form the extension groove (12), the extension groove (12) includes a lifting section (121), the bottom of the lifting section (121) near the communication port (16) is inclined away from the bottom of the annular groove (11).

3. The burner of claim 2, wherein The ejector cover (4) includes an installation section (41) and an extension section (42) connected to each other. The installation section (41) is detachably connected to the base (1). The extension section (42) covers at least part of the top of the lifting section (121). The end of the extension section (42) away from the installation section (41) is inclined toward the direction close to the air distribution plate (3).

4. The burner of claim 3, wherein The base (1) includes a base plate (15), an inner sidewall (13) and an outer sidewall (14) that are coaxially arranged and interlocked. The base plate (15) is connected to the inner sidewall (13) and the outer sidewall (14) to form the annular groove (11). The extension groove (12) is opened on the base plate (15). The extension section (42) is embedded between the inner sidewall (13) and the outer sidewall (14). The extension groove (12), the extension section (42), and a portion of the inner sidewall (13) and a portion of the outer sidewall (14) enclose a portion of the extension pipe.

5. The burner of claim 3, wherein The extension pipe includes a diffuser pipe disposed between the connecting port (16) and the lifting section (121), the two ends of the diffuser pipe being a large-diameter end and a small-diameter end, the large-diameter end being connected to the lifting section (121), and the small-diameter end being connected to the connecting port (16); The extension groove (12) further includes a diffuser section (122), one end of which is connected to the lifting section (121) and the other end is connected to the connecting port (16). The installation section (41) is placed over the diffuser section (122) to form the diffuser pipe.

6. The burner of claim 1, wherein The ejector cover (4) has a support end plate (43) at the end away from the communication port (16), the upper surface of the support end plate (43) extends in the horizontal direction, and the support end plate (43) is used to support the air equalization plate (3).

7. The burner of claim 6, wherein The supporting end plate (43) and the air distribution plate (3) are detachably connected; and / or, One of the support end plate (43) and the air distribution plate (3) has a positioning hole (32), and the other has a positioning protrusion (44), which is inserted into the positioning hole (32).

8. Burner according to any of claims 1-7, characterized in that The gas equalization plate (3) has a plurality of flow holes (31) arranged at even intervals on the gas equalization plate (3).

9. Burner according to any of claims 1-7, characterized in that The annular groove (11) has two extension grooves (12). The burner includes two ejector tubes (2) and two ejector covers (4). The two ejector covers (4) and the two extension grooves (12) correspond one-to-one to form two extension pipes. The two extension pipes are respectively connected to the two ejector tubes (2). The two ejector tubes (2) are symmetrically arranged with respect to the center of the base (1). At least part of the extension pipes extend in an arc around the center of the base (1). The airflow flows in the same direction after passing through the two extension pipes.

10. Gas hob, characterized in that Including the burner as described in any one of claims 1-9.

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