Infrared energy-saving cover and gas appliance

Abstract

Disclosed in the present invention are an infrared energy-saving cover and a gas appliance, aiming at overcoming the defects in the prior art that the gas appliance has low gas combustion efficiency and heat is easily dissipated. The present invention solves the described technical problems by means of the following technical solutions: the infrared energy-saving cover comprises: an infrared generating cover and a thermal insulation cover arranged outside the infrared generating cover; an air preheating cavity is formed between the thermal insulation cover and the infrared generating cover; the air preheating cavity is provided with an air inlet channel in communication with outside air, and a plurality of air outlets are formed on and pass through the infrared generating cover; and air enters from the air inlet channel, passes through the air preheating cavity, and then flows out from the air outlets. The air flows in from the bottom of the air preheating cavity. When passing through the air preheating cavity, the air is heated, and the heated air is ejected from the air outlets to undergo high-temperature secondary combustion with gas. In a combustion-supporting environment of high-temperature air obtained after heating in the air preheating cavity, a combustible gas can be completely consumed by means of secondary combustion, thereby preventing the formation of harmful gases and soot deposition.

Description

An infrared energy-saving cover and gas appliance Technical Field

[0001] This invention relates to the field of household stove technology, and more specifically, to an infrared energy-saving cover and a gas appliance. Background Technology

[0002] Existing gas appliances are divided into two types: fully premixed and partially premixed.

[0003] Fully premixed infrared gas appliances are gaining popularity due to their advantages such as complete combustion, low pollution, and high thermal efficiency. However, because the combustion reaction occurs in ceramic micropores or metal sheet gaps, they have drawbacks such as high material requirements and high manufacturing costs; backfire can occur when the gas pressure is unstable, resulting in a shorter service life. These disadvantages have hindered their widespread adoption.

[0004] Partially premixed gas appliances are currently the mainstream type of gas appliance. They rely on the flame of burning gas to heat the cookware, with the flame enveloping the cookware and transferring heat through convection; this is known as an atmospheric gas appliance. Because of its partially premixed nature, it is inexpensive, has mature manufacturing processes, and does not experience backfire. However, when cooking, the cookware itself absorbs heat from the food, resulting in a lower temperature. This can easily lower the flame temperature, leading to incomplete combustion on the bottom surface of the cookware, forming harmful gases and causing carbon black precipitation, commonly known as a "blackened pot." Simultaneously, the lower part of the flame is exposed to the air, causing a large amount of heat to dissipate into the surrounding air, reducing thermal efficiency.

[0005] Therefore, whether we can avoid the shortcomings of existing fully premixed gas appliances, absorb some of the advantages of premixed gas appliances, and improve the combustion efficiency of gas is a direction that people have been trying to explore.

[0006] Chinese Patent Publication No. CN201420004301, published on July 9, 2014, entitled "An Inner Wall for a Heat-Concentrating Stove Furnace." This application, by incorporating a heat conductor and a heat-concentrating element, effectively absorbs residual heat and reflects heat energy. While this method can reduce heat loss and improve heat utilization efficiency, it cannot fundamentally improve the combustion efficiency of the gas. Summary of the Invention

[0007] This invention overcomes the shortcomings of existing gas appliances, such as low combustion efficiency and easy heat loss, by providing an infrared energy-saving cover. It preheats the air participating in secondary combustion within an air preheating chamber. Inspired by the primary combustion flame, the preheated air flows through widely distributed air outlets, causing secondary high-temperature combustion to occur dispersed along the heated appliance and close to its bottom, expanding the heating area. The high temperature of the chemical reaction directly creates significant thermal convection impact on the heated appliance, ensuring complete combustion of the secondary fuels under the impact of the high-temperature air, achieving flameless combustion. The uniform and intense secondary combustion reaction releases high energy and emits infrared radiation. The thermal convection caused by the combustion reaction between the hot air ejected from the air outlets and the high-speed gas mixture, combined with infrared radiation, improves thermal efficiency. In this high-temperature infrared radiation environment, incompletely burned gas is fully combusted, and gas cooled by the bottom of the pot reignites, improving combustion efficiency and preventing the formation of harmful gases and a blackened pot.

[0008] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: an infrared energy-saving cover, comprising: an infrared generating cover and a heat insulation cover disposed outside the infrared generating cover; an air preheating chamber is provided between the heat insulation cover and the infrared generating cover; the air preheating chamber is provided with an air intake channel communicating with the outside air, and a plurality of air outlets are provided through the infrared generating cover; air enters from the air intake channel, passes through the air preheating chamber, and flows out from the air outlets.

[0009] The actual usage process of the infrared energy-saving cover of this invention is as follows: Remove the original gas stove bracket, place the infrared energy-saving cover of this application in the original gas stove bracket position, place the pot, and ignite the stove. Initially, the original gas stove flame remains blue, gradually impacting the cavity shell of the air preheating chamber. During this process, the air outlet of the air preheating chamber begins to flow out due to the ejection effect of the gas flame. At this time, the air enters from the lower outer side of the infrared energy-saving cover of this application, initially absorbing heat from the gas stove panel and the lower part of the energy-saving cover before entering the air intake channel; after further absorbing heat from the stove head and stove panel, it enters the hollow structure of the air preheating chamber, absorbing heat from the cavity shell of the air preheating chamber before flowing out from the air outlet. As the temperature of the infrared generator cover gradually rises, the preheated air temperature increases, and the air preheating chamber is activated. After about 40 seconds, the surface of the infrared generator cover near the combustion surface begins to turn red, and after two minutes, the entire cavity shell of the infrared generator cover turns red. At this point, the flame from the small burner at the bottom of the gas stove is still blue, while the flame from the large burner cap is blue at the bottom and becomes a reddish mist after entering the energy-saving cover. Once it reaches the upper part of the infrared energy-saving cover, the flame is no longer visible, and the entire infrared energy-saving cover is in a red, transparent radiation environment. At this time, the cookware is noticeably heated. After 4 minutes, the infrared energy-saving cover enters a stable working state. Due to the thick insulation, the temperature difference between the lower outer part of the infrared energy-saving cover and the ambient temperature is not significant after 10 minutes. After half an hour, the temperature on the lower outer part continues to rise before stabilizing. When the gas stove switch knob is turned down, the infrared radiation environment gradually darkens as the flame decreases, and the infrared radiation area shifts downwards until the infrared radiation disappears after the low flame. Due to the use of the insulation cover, the infrared energy-saving cover serves to prevent wind and maintain heat. When the flame is increased from low to high, the infrared radiation quickly restarts because of the residual heat. When the cookware is removed, the gas stove flame rises and no longer flows through the infrared radiation area, and the infrared radiation quickly disappears; when it is moved back shortly after being removed, the infrared radiation restarts within seconds. This process aligns with the common cooking habits of gas stove users. Testing revealed no incomplete combustion during the initial and restart phases.

[0010] The air preheating chamber has a hollow structure, with the air intake channel located at the bottom. Air flows in from the bottom of the preheating chamber, is heated as it passes through, and is then ejected from the air outlet, where it undergoes high-temperature secondary combustion with the fuel gas. The high temperature generated by this secondary combustion disperses along the bottom of the heated appliance, and the chemical reaction directly impacts the appliance (cookware) with significant thermal convection, ensuring complete combustion of the secondary fuel under the influence of the high-temperature air, achieving flameless combustion. This uniform and intense combustion releases high energy and emits infrared radiation. The combustion reaction between the hot air ejected from the air outlet and the high-speed fuel gas mixture triggers thermal convection, which, combined with infrared radiation, improves thermal efficiency. In this high-temperature infrared radiation environment, any unburned fuel gas is fully combusted, and fuel gas cooled by the bottom of the pot reignites. The high-temperature air-supported combustion environment in the preheating chamber ensures that combustible gases are completely consumed, preventing the formation of harmful gases and a blackened pot.

[0011] Preferably, the air preheating chamber is provided with several layered plates distributed along the thickness direction, which divide the air preheating chamber into several partitioned chambers along the thickness direction; the two ends of adjacent partitioned chambers are staggered and connected to form a curved channel.

[0012] The multi-layered partition chamber forms a layered space within the air preheating chamber. This layered space serves as the flow space for secondary air, which ultimately exits through the air outlet to participate in secondary combustion. The shape of this layered space closely resembles that of the infrared generator, making it easier for the secondary air to approach and exchange heat with the infrared generator, thus facilitating preheating. A cross-section larger than the corresponding total cross-section of the air outlet is necessary to ensure orderly flow of secondary air. Furthermore, a larger curved channel and a smaller air outlet increase the air velocity at the outlet, which is beneficial for the secondary combustion reaction.

[0013] The infrared generating area is the region near the bottom of the pot within the infrared generating hood. The air preheating chamber is the preheating area before the preheated air enters the infrared generating area, and it is relatively close to the infrared generating area, resulting in a higher temperature. When the air inlet cross-section of the layered space is larger than the corresponding total air outlet cross-section (the Venturi effect is more pronounced when the cross-section is 6-10 times larger), the partition cavity is thin and uniform. The high-temperature radiation from the infrared generating hood is more uniformly distributed within the layered space, with minimal reduction in the temperature gradient and limited heat absorption by the infrared generating hood, thus promoting the generation and maintenance of infrared rays. With a thinner partition cavity, it is closer to the infrared generating area, making it easier to maintain the high temperature, resulting in a higher preheated air temperature. Furthermore, in practical applications, the layered plate is also designed to be relatively thin, specifically between 0.3 mm and 1.2 mm, preferably 0.8 mm.

[0014] Preferably, a number of chamber partition plates are provided in the partition cavity near the infrared generator cover. The chamber partition plates are arranged vertically along the side wall of the partition cavity, and the chamber partition plates divide the partition cavity into small air intake chambers. Each small air intake chamber has an air intake hole at one end and is connected to at least one air outlet at the other end.

[0015] The partition plates of the chambers serve several functions: First, the walls of the partitioned air intake chambers act as insulation, reducing heat conduction outwards. Second, they extend the flow path of the preheated air, increasing preheating time and raising its temperature. Third, they allow for the arrangement of air outlet sizes in each intake chamber, ensuring orderly and efficient preheating air flow (each intake chamber corresponds to a ring of air outlets; if a ring requires a larger supply of preheated air, the corresponding outlet is enlarged, and vice versa). Fourth, they mitigate backflow and leakage of preheated air caused by external winds. Fifth, the added partition plates and layered plates increase the inner surface area of ​​the air preheating chamber, increasing the chances of contact and collision between the preheated air and the inner wall, facilitating heat exchange and improving preheating efficiency. Looking at the normal direction of the cavity wall of the chamber partition plate, the greater the inclination angle and the more steps the inclined chamber partition plate or stepped chamber partition plate has, the more small air intake cavities the normal line passes through, the better the heat insulation effect, and the higher the preheated air temperature.

[0016] Preferably, the side wall of the infrared generator cover is provided with several protrusions, and the air outlet is located on the protrusions.

[0017] The protruding parts are distributed on the inner side of the infrared generator cover, forming an undulating surface on the surface of the infrared generator cover. This increases the reflective area of ​​the infrared generator cover surface, increasing the chance of the cookware receiving secondary reflected radiation; it also causes the air outlet to collide with the gas flame, resulting in more uniform mixing, stronger turbulence, and more complete secondary combustion of the gas.

[0018] As a preferred option, an air nozzle is provided at the air outlet, and the air nozzle has a tubular structure.

[0019] When the tubular nozzle structure extends into the air preheating chamber, the air outlet of the infrared generation area is enveloped by the high-temperature fuel mixture. After the high-temperature air is ejected from the outlet, the reaction near the outlet is intense, and the air is infrared-transformed first, further promoting the temperature rise of the preheated air and providing a strong fuel combustion capacity. Simultaneously, the space between the tubular nozzle structures becomes a channel for the fuel mixture to be discharged upwards, and this channel also provides space for the preheating of the tubular nozzle structure. The secondary combustion reaction area shifts upwards due to the extension of the tubular nozzle structure, bringing it closer to the bottom of the heated appliance, thus improving thermal efficiency. This layout avoids the situation where some existing energy-saving covers are placed too far from the bottom of the heated appliance to ensure smooth fuel mixture discharge, resulting in low heating efficiency. At the same time, the extension of the tubular nozzle structure provides a channel for flue gas discharge; it also avoids the situation where some existing energy-saving covers are placed too close to the bottom of the pot to improve thermal efficiency, resulting in narrow flue gas discharge space, insufficient combustion reaction, and potentially safety accidents.

[0020] Preferably, both the infrared generator cover and the air preheating chamber are annular structures.

[0021] The infrared generator cover has a ring-shaped structure, which includes a strictly circular ring structure, as well as a triangular or polygonal ring formed by three or more sides. The ring-shaped infrared generator cover is suitable for use on different types of stovetops.

[0022] Preferably, the air preheating chamber is provided with several dividing blocks arranged circumferentially along the axis of the infrared generator cover. The dividing blocks divide the air preheating chamber into several small preheating chambers along the circumferential direction of the axis of the infrared generator cover.

[0023] The spiral and spoke-shaped dividers separate the air preheating chamber into several smaller preheating cavities. This forces the air entering these cavities to flow along a curved path, increasing the flow path and time of the preheated air. This results in more thorough heat exchange within the cavities, leading to higher preheated air temperatures. Upon reaching the air outlet, the air is ejected tangentially, creating a swirling effect.

[0024] In addition, the adjacent preheating chambers are isolated from each other, and the air flow in each preheating chamber is not affected by the other preheating chambers. This makes the air flow in each preheating chamber more stable, and the preheated air flowing out of the air outlet more stable. As a result, the air participating in the secondary combustion of the gas is more stable, and the efficiency of the secondary combustion of the gas is improved.

[0025] Preferably, the dividing block is spiral-shaped.

[0026] The spiral-shaped divider separates the air preheating chamber into several smaller preheating cavities. This forces the air entering these cavities to flow along a curved path, increasing the flow path and time of the preheated air. This results in more thorough heat exchange within the cavities, leading to higher preheated air temperatures. The air is then ejected tangentially at the outlet, further enhancing the formation of a swirling effect.

[0027] Preferably, the infrared generator cover has a flat plate structure.

[0028] The infrared generator cover can also be designed as a flat panel structure, thus adapting to use in barbecue ovens and teppanyaki grills.

[0029] Preferably, an infrared auxiliary generating component is provided inside the infrared generating cover, and the infrared auxiliary generating component includes the infrared auxiliary generating cover.

[0030] The metal mesh infrared auxiliary generator is easily heated and inflamed by the flame gas. The preheated air from the air outlet flows upward and encounters the inflamed metal mesh, where it is dispersed by the mesh openings. The flame gas flowing through it burns rapidly under the influence of the inflamed metal mesh, which is rich in high-temperature combustion air, thereby improving the efficiency of secondary combustion of the fuel gas.

[0031] Preferably, it also includes a return air cavity, which is fitted into the air preheating cavity; the top circumference of the infrared generator cover is provided with a return air inlet that communicates with the return air cavity, and the end of the return air cavity away from the return air inlet is provided with a return air outlet; the return air outlet is connected to the chimney.

[0032] Besides ensuring that combustion gases are concentrated and expelled, preventing them from flowing into spaces accessible to people, the chimney also creates negative pressure upon startup, effectively drawing in the flue gas. This suction prevents flame leakage from the observation and pressure relief device, instead drawing in a small amount of outside air and expelling it through the flue. The observation and pressure relief device allows observation of the gas appliance's combustion process and maintains stable internal pressure, preventing sudden expansion of the combustion flame. The exhaust system uses either natural draft exhaust or fan-assisted exhaust.

[0033] During the process of flue gas passing through the return air chamber, the residual heat can be reabsorbed by the air in the air preheating chamber, thus the air preheating chamber can recover the residual heat from the flue gas.

[0034] The chimney effect created by the chimney can accelerate the airflow inside the infrared energy-saving cover, promote the operation of the return air chamber, create negative pressure in the fire observation and pressure relief device, and prevent the combustion products of the gas from being discharged into the cooking environment at close range, thus protecting the health of the cooks.

[0035] This application also provides a gas appliance, including the aforementioned infrared energy-saving cover, and further including a burner head disposed in the middle of the infrared generating cover.

[0036] Gas appliances made with infrared energy-saving covers have high gas combustion efficiency and save fuel, while also having good windproof function.

[0037] This application also provides a gas appliance, including the aforementioned infrared energy-saving cover, which has a flat plate structure, and also includes a gas pipe.

[0038] The flat infrared energy-saving cover is suitable for some special situations, such as ovens and barbecue grills, thereby improving the combustion efficiency of gas in ovens and barbecue grills.

[0039] Preferably, the infrared generator is vertically positioned; a mesh cooker is positioned on the side of the infrared generator away from the air preheating chamber; and a gas pipe is positioned at the bottom between the mesh cooker and the infrared generator.

[0040] Preferably, the infrared generator is tilted and the gas pipeline is located at the lower end of the infrared generator.

[0041] Compared with the prior art, the beneficial effects of the present invention are as follows: In the gas appliance implementing the present invention, when in low flame mode, the air ejected from the lower air outlet participates in combustion. As the gas supply is gradually increased, the combustion reaction shifts upward, and the air ejected from the gradually upward air outlets participates in combustion, until air from the corresponding air outlets participates in combustion even under maximum heat load. This structural layout allows the heat load of the gas appliance to be continuously adjusted, and the difference in thermal efficiency under different heat load conditions is small.

[0042] Based on tests of existing premixed gas stoves, the energy-saving effect of using the infrared energy-saving cover in this application is significant. Compared with using a regular bracket to boil water, when tested without turning off the flame, the time to boil the same amount of water is reduced by about 38%, demonstrating a significant energy-saving effect. The CO and nitrogen oxide content in the flue gas is reduced, and there is no carbon buildup on the bottom of the pot. In fact, it can burn away the previous carbon buildup on the cookware.

[0043] After the implementation of this invention, flameless combustion is achieved in the high-temperature combustion zone during cooking, preventing flames from spreading to the outer edge of the pot. The resulting heat radiation and convection are largely absorbed by the bottom of the pot, significantly reducing the temperature of the exhaust gas emitted from the outer edge during normal use. This reduces the risk of damage to the handle of cooking utensils such as spatulas from heat after being placed in the pot, or burns from repeated use. Infrared high-temperature cooking reduces cooking time, improves production efficiency, and enhances the taste of food, making it particularly suitable for the stir-frying requirements of Chinese cuisine.

[0044] This invention relates to an infrared energy-saving cover, a device that generates infrared rays through secondary combustion of gas flames. It is suitable for some premixed gas appliances. For fully premixed gas appliances, if primary combustion is complete, secondary combustion is almost nonexistent. This energy-saving cover provides heat insulation and wind protection but does not provide secondary oxygen supply for combustion. However, in actual use, due to factors such as changes in gas pressure and premixed air ratio, the primary combustion of fully premixed gas appliances is incomplete, requiring secondary combustion. However, the high temperature of the exhaust gases from the primary combustion of fully premixed gas appliances reacts immediately upon contact with external air, making this secondary combustion appear less noticeable. Using this energy-saving cover on fully premixed gas appliances allows for secondary combustion air supply from the cover itself, rather than being obtained from the outside air, after changes in combustion conditions. As a protective function against changes in combustion conditions, the energy-saving cover plays a positive role in the practical use of fully premixed gas appliances. Furthermore, the air preheating chamber allows preheated air to return heat conducted away to the combustion zone to reheat the cookware. The flexible shape of the infrared energy-saving cover can envelop the cookware, reducing heat diffusion and preventing heat loss due to external airflow. In conclusion, the energy-saving cover is significantly effective when used on fully premixed gas appliances. Attached Figure Description

[0045] Figure 1 is a cross-sectional view of the present invention.

[0046] Figure 2 is a three-dimensional structural diagram of the present invention.

[0047] Figure 3 is a cross-sectional view of the two-layered plate in Embodiment 2 of the present invention.

[0048] Figure 4 is a cross-sectional view of the layered plate in Embodiment 2 of the present invention when there is one layer.

[0049] Figure 5 is a schematic diagram of the structure of the present invention when a chamber partition plate is provided in the partition cavity.

[0050] Figure 6 is a schematic diagram of the structure of the chamber partition plate of the present invention, which is arranged in a horizontal direction.

[0051] Figure 7 is a schematic diagram of the structure when the chamber partition plate of the present invention is distributed in a wavy shape.

[0052] Figure 8 is a schematic diagram of the structure of the chamber partitions of the present invention when they are distributed in a stepped manner.

[0053] Figure 9 is a schematic diagram of the present invention when the dividing blocks are distributed in a spoke-shaped pattern.

[0054] Figure 10 is a schematic diagram of the present invention when the dividing blocks are distributed in a spiral shape.

[0055] Figure 11 is a three-dimensional structural diagram of the infrared generator cover of the present invention with a protruding head.

[0056] Figure 12 is a three-dimensional structural diagram of the infrared generator cover of the present invention when it is distributed in a spiral shape with convex heads.

[0057] Figure 13 is a three-dimensional structural diagram of the present invention with an air nozzle installed on the air outlet.

[0058] Figure 14 is a cross-sectional view of the air outlet of the present invention with an air nozzle installed.

[0059] Figure 15 is a schematic diagram of the structure of the present invention when the nozzle is in the shape of a tree branch.

[0060] Figure 16 is a schematic diagram of the structure of the present invention when the air nozzle is lotus seedpod shaped.

[0061] Figure 17 is a structural schematic diagram of the present invention when the air nozzle is in a vertical shape.

[0062] Figure 18 is a structural schematic diagram of the air nozzle of the present invention when it is in an inclined form.

[0063] Figure 19 is a schematic diagram of the structure of the air nozzle of the present invention when it is in a spiral extension state.

[0064] Figure 20 is a schematic diagram of the structure of the present invention when the air nozzle extends into both the air preheating chamber and the infrared generation area.

[0065] Figure 21 is a schematic diagram of the air outlet of the nozzle of the present invention being obliquely cut.

[0066] Figure 22 is a schematic diagram of the present invention when the air nozzle is only inserted into the air preheating chamber.

[0067] Figure 23 is a schematic diagram of the air outlet of the nozzle of the present invention being toothed.

[0068] Figure 24 is a schematic diagram of the air inlet cross-sectional area of ​​the air nozzle of the present invention being larger than the air outlet cross-sectional area.

[0069] Figure 25 is a schematic diagram of the structure of the present invention, in which the air nozzle is extended and wavy.

[0070] Figure 26 is a cross-sectional view of the present invention with an infrared auxiliary generator cover.

[0071] Figure 27 is a three-dimensional structural diagram of the infrared auxiliary generator cover of the present invention when it is an arc-shaped surface.

[0072] Figure 28 is a three-dimensional structural diagram of the infrared auxiliary generator cover of the present invention when it is corrugated.

[0073] Figure 29 is a three-dimensional structural diagram of the present invention when an infrared-assisted generating spring is provided.

[0074] Figure 30 is a cross-sectional view of the present invention with a return air chamber and a chimney.

[0075] Figure 31 is a cross-sectional view of the present invention with a return air chamber, a chimney, and a condensation device.

[0076] Figure 32 is a top view of the portable gas stove of the present invention.

[0077] Figure 33 is a cross-sectional view of the outdoor stove of the present invention.

[0078] Figure 34 is a cross-sectional view of the integrated heat collection furnace of the present invention.

[0079] Figure 35 is a cross-sectional view of the pancake oven of the present invention.

[0080] Figure 36 is a cross-sectional view of the braising furnace of the present invention.

[0081] Figure 37 is a cross-sectional view of the gas-fired rice cooker of the present invention.

[0082] Figure 38 is a cross-sectional view of the fuel oil furnace of the present invention.

[0083] Figure 39 is a cross-sectional view of the alcohol furnace of the present invention.

[0084] Figure 40 is a cross-sectional view of the oven of the present invention.

[0085] Figure 41 is a three-dimensional structural diagram of the barbecue oven of the present invention.

[0086] Figure 42 is a three-dimensional structural diagram of the fire-covered teppanyaki grill of the present invention.

[0087] Figure 43 is a three-dimensional structural diagram of the fire-covered teppanyaki grill of the present invention when a flat pot is installed.

[0088] In the diagram: 1. Infrared generator cover, 11. Protruding head, 12. Air nozzle; 2. Thermal insulation cover, 21. Insulation wall, 22. Insulation cavity; 3. Air preheating cavity, 31. Air intake channel, 32. Air outlet, 33. Support, 34. Layered plate, 341. First layered plate, 3411. First connecting hole, 342. Second layered plate, 3421. Second connecting hole, 35. Separating cavity, 351. First separating cavity, 352. Second separating cavity, 353. Third separating cavity, 36. Chamber partition plate, 37. Small air intake chamber, 371. Air intake hole, 38. Dividing baffle; 4. Infrared auxiliary generator cover, 41. Infrared auxiliary generator spring; 5. Return air cavity, 51. Return air inlet, 52. Return air outlet, 53. Transparent fire observation window, 54. Pressure relief groove, 55. Condensation device, 56. Chimney; 6. Furnace body; 61. Gas tank compartment; 62. Barrel-shaped opening; 63. Support legs; 64. Gas pipeline; 65. Feed fan; 66. Oven door; 67. Flat cookware; 68. Oil drip tray; 7. Burner head; 8. Flat cookware; 81. Fin-shaped structure; 9. Gas pipeline; 91. Flame outlet. Detailed Implementation

[0089] The technical solution of the present invention will be further described in detail below through specific embodiments and in conjunction with the accompanying drawings: Embodiment 1: As shown in Figures 1 and 2, an infrared energy-saving cover includes: an infrared generating cover 1 and a heat-insulating cover 2 disposed outside the infrared generating cover 1. An air preheating chamber 3 is provided between the heat-insulating cover 2 and the infrared generating cover 1; the air preheating chamber 3 is provided with an air intake channel 31 communicating with the outside air, and a plurality of air outlets 32 are provided through the infrared generating cover 1; air enters from the air intake channel 31, passes through the air preheating chamber 3, and flows out from the air outlets 32.

[0090] In one embodiment, the infrared generator 1 has a ring structure. The ring structure includes a strictly circular ring structure, as well as a triangular or polygonal ring formed by three or more sides. In this embodiment, the infrared generator 1 has a circular ring structure and is a trumpet shape with a gradually increasing opening. Several supports 33 (four supports in this embodiment) are arranged along the inner circumference of the infrared generator 1. The supports 33 protrude from the surface of the infrared generator 1 and are arranged along the axial direction of the infrared generator 1. In use, a pot is placed on the supports 33, with the bottom of the pot conforming to the surface shape of the infrared generator 1. The gas flame at the bottom flows along the bottom of the pot, heating the infrared generator 1, thereby heating the air preheating chamber 3.

[0091] The infrared generating area or infrared radiation area is the area near the bottom of the pot when the infrared generating cover 1 is in use. The air preheating chamber 3 has a hollow structure, and the air intake channel 31 is located at the bottom of the air preheating chamber 3. Air flows in from the bottom of the air preheating chamber 3. When passing through the air preheating chamber 3, the air is heated. The heated air is ejected from the air outlet 32 ​​and undergoes high-temperature secondary combustion with the fuel gas. The high temperature generated by the secondary combustion is dispersed along the bottom of the heated appliance. The high temperature generated by the chemical reaction of the secondary combustion directly creates a large amount of thermal convection impact on the heated appliance (pot), so that the secondary combustion materials are completely burned under the impact of the high-temperature air, achieving flameless combustion. The uniform and intense combustion releases high energy and emits infrared rays. The combustion reaction between the hot air ejected from the air outlet 32 ​​and the high-speed fuel gas mixture triggers thermal convection, which, together with infrared radiation, improves thermal efficiency. In this high-temperature infrared radiation environment, the fuel gas that is not completely burned is fully burned, and the fuel gas cooled by the bottom of the pot reignites. In the high-temperature air-supported combustion environment heated by the air preheating chamber 3, the combustible gas can be completely consumed, avoiding the formation of harmful gases and black pots.

[0092] In the gas appliance implementing this invention, during low flame operation, the air ejected from the lower air outlet 32 ​​participates in combustion. As the gas supply is gradually increased, the combustion reaction shifts upward, and air ejected from the gradually upward-facing air outlet 32 ​​participates in combustion, until air from the corresponding air outlet 32 ​​also participates in combustion even under maximum heat load. This structural layout allows for continuous adjustment of the gas appliance's heat load, with minimal difference in thermal efficiency under different heat load conditions.

[0093] Based on tests of existing premixed gas stoves, the energy-saving effect of using the infrared energy-saving cover in this application is significant. Compared with using a regular bracket to boil water, when tested without turning off the flame, the time to boil the same amount of water is reduced by about 38%, demonstrating a significant energy-saving effect. The CO and nitrogen oxide content in the flue gas is reduced, and there is no carbon buildup on the bottom of the pot. In fact, it can burn away the previous carbon buildup on the cookware.

[0094] After the implementation of this invention, flameless combustion is achieved in the high-temperature combustion zone during cooking, preventing flames from spreading to the outer edge of the pot. The resulting heat radiation and convection are largely absorbed by the bottom of the pot, significantly reducing the temperature of the exhaust gas emitted from the outer edge during normal use. This reduces the risk of damage to the handle of cooking utensils such as spatulas from heat after being placed in the pot, or burns from repeated use. Infrared high-temperature cooking reduces cooking time, improves production efficiency, and enhances the taste of food, making it particularly suitable for the stir-frying requirements of Chinese cuisine.

[0095] This invention relates to an infrared energy-saving cover, a device that generates infrared rays through secondary combustion of gas flames. It is suitable for some premixed gas appliances. For fully premixed gas appliances, if primary combustion is complete, secondary combustion is almost nonexistent. This energy-saving cover provides heat insulation and wind protection but does not provide secondary oxygen supply for combustion. However, in actual use, due to factors such as changes in gas pressure and premixed air ratio, the primary combustion of fully premixed gas appliances is incomplete, requiring secondary combustion. However, the high temperature of the exhaust gases from the primary combustion of fully premixed gas appliances causes an immediate reaction upon contact with external air, making this secondary combustion appear less noticeable. Using this energy-saving cover on fully premixed gas appliances allows for secondary combustion air supply from the cover itself, rather than from outside air, when combustion conditions change. As a protective function against changes in combustion conditions, the energy-saving cover plays a positive role in the practical use of fully premixed gas appliances. Furthermore, the air preheating chamber 3 can reheat the cookware by bringing the conducted heat back to the combustion zone. The flexible shape of the infrared energy-saving cover can envelop the cookware, reducing heat diffusion and preventing heat loss due to outside airflow. In conclusion, the energy-saving cover is significantly effective when used on fully premixed gas appliances.

[0096] The actual usage process of this invention is as follows: Remove the original gas stove support, place the infrared energy-saving cover of this application in the original gas stove support position, place the pot, and ignite the stove. Initially, the original gas stove flame remains blue, gradually impacting the cavity shell of the air preheating chamber 3. During this process, the air outlet of the air preheating chamber 3 begins to flow out due to the ejection effect of the gas flame. At this time, the air enters from the lower outer side of the infrared energy-saving cover of this application, initially absorbing heat from the gas stove panel and the lower part of the energy-saving cover before entering the air intake channel 31; further absorbing heat from the burner head and stove panel before entering the hollow structure of the air preheating chamber 3, and after absorbing heat from the cavity shell of the air preheating chamber 3, it flows out from the air outlet 32. As the temperature of the infrared generator cover 1 gradually rises, the preheated air temperature increases, and the air preheating chamber 3 is activated. After about 40 seconds, the surface of the infrared generator cover 1 near the combustion surface begins to turn red, and after two minutes, the entire cavity shell of the infrared generator cover 1 turns red. At this point, the flame from the small burner at the bottom of the gas stove is still blue, while the flame from the large burner cap is blue at the bottom and becomes a reddish mist after entering the energy-saving cover. Once it reaches the upper part of the infrared energy-saving cover, the flame is no longer visible, and the entire infrared energy-saving cover is in a red, transparent radiation environment. At this time, the cookware is noticeably heated. After 4 minutes, the infrared energy-saving cover enters a stable working state. Due to the thick insulation, the temperature difference between the lower outer part of the infrared energy-saving cover and the ambient temperature is not significant after 10 minutes of operation. After half an hour, the temperature on the lower outer part continues to rise before stabilizing. When the gas stove switch knob is turned down, the infrared radiation environment gradually darkens as the flame decreases, and the infrared radiation area shifts downwards until the infrared radiation disappears after the low flame. Due to the use of the insulation cover 2, the infrared energy-saving cover serves to prevent wind and maintain heat. When the flame is increased from low to high, the infrared radiation quickly restarts because of the residual heat. When the cookware is removed, the gas stove flame rises and no longer flows through the infrared radiation area, and the infrared radiation quickly disappears; when it is moved back shortly after being removed, the infrared radiation restarts within seconds. This process aligns with the common cooking habits of gas stove users. Tests have shown no incomplete combustion during the initial and restart phases.

[0097] In one embodiment, the shell of the air preheating chamber 3 can be made of a single layer, double layer, or multiple layers of material. When a double layer or single layer material is used, they are bonded together using a composite process. The shell material of the air preheating chamber 3 includes, but is not limited to, metal, ceramic, composite ceramic, or thermal insulation material with a certain strength.

[0098] In one embodiment, the shell of the air preheating chamber 3 can be made of a composite of a stainless steel layer and a titanium alloy layer. The titanium alloy layer is located near the infrared radiation region; the stainless steel layer is located near the side of the air preheating chamber 3.

[0099] In one embodiment, the shell of the air preheating cavity 3 may be composed of a heat-absorbing coating, a metal layer and an infrared generating layer; the heat-absorbing layer is disposed on the side close to the air preheating cavity 3.

[0100] The composite process used in the shell of the air preheating chamber 3 ensures strength, improves surface properties, and reduces costs. For example, electroplating stainless steel can improve the reflectivity of the shell surface; composite materials for gas reaction catalysts can improve combustion efficiency; composites of stainless steel and titanium alloys can reduce costs while ensuring high performance; and composites of metal and ceramics can improve high-temperature resistance and infrared generation capabilities.

[0101] In one embodiment, the bottom of the cookware can be configured with an irregularly shaped surface structure of undulating grooves, fins, and ravine textures. This can increase the surface area of ​​the heated surface of the cookware, absorb more heat, and at the same time obstruct the flow path of the high-temperature combustion gas mixture, forming more rotating vortices. This increases the flow path of the flue gas, delays the residence time of the flue gas in the heated surface area of ​​the cookware, and promotes the absorption of heat by the cookware. The high-temperature air at the air outlet ensures the full reaction of the combustion gas and avoids the carbon deposits formed by incomplete combustion from clogging the irregularly shaped surface structure of the undulating grooves, fins, and ravine textures at the bottom of the cookware.

[0102] The cookware and the air preheating chamber 3 have similar shapes on the side near the combustion reaction. When the cookware being heated has a barrel-shaped structure, the infrared energy-saving cover also has a barrel-shaped structure, which allows the cookware to be more fully enclosed by the secondary combustion area, forming a larger heating area. At the same time, the proportion of the heat insulation part is also increased, further improving the thermal efficiency.

[0103] When the cookware has a flat structure (such as a teppanyaki cookware), the infrared energy-saving cover can also have a flat structure.

[0104] When the gas flame does not actively impact the air preheating chamber 3 shell, under the pressure of the cookware lid, the flame enters the infrared generation area and generates high-temperature combustion to produce infrared radiation. Therefore, when the cookware is removed and not in use but the flame is maintained, the infrared radiation quickly disappears, the gas flame no longer heats the infrared energy-saving cover, and the infrared energy-saving cover is as if it was never placed, and the gas appliance reverts to its inherent combustion mode.

[0105] Unlike fully premixed gas stoves, the feature of this invention is the secondary reaction and multi-point distributed combustion. This makes it unrestricted by the shape of the cookware, allowing it to adapt to different cookware shapes and manufacture products with cookware of various shapes. This avoids the uneven cooking caused by the porous ceramic plane of existing infrared gas stoves not matching the shape of the cookware.

[0106] Similar to fully premixed gas appliances, their heating method is mostly infrared radiation. Although the heat convection and heat radiation from the secondary combustion at the air outlet promote each other, the bottom of the cookware still needs to be made of a material that easily absorbs infrared radiation. Increasing the surface area by adding roughness or uneven structure can promote absorption and improve thermal efficiency.

[0107] Example 2: As shown in Figures 3 and 4, this example is similar in structure to Example 1, except that the air preheating chamber 3 has several layered plates 34 distributed along the thickness direction. The layered plates 34 are annular, and the several layered plates 34 divide the air preheating chamber 3 into several partitioned chambers 35 along the thickness direction. The partitioned chambers 35 are coaxially arranged, and the two ends of adjacent partitioned chambers 35 are staggered and connected to form a curved channel. The cross-sectional area of ​​the curved channel is larger than the total cross-sectional area of ​​the air outlet 32. Since the infrared generator cover 1 in this example is an annular structure, the shape of the partitioned chamber 32 is also annular; however, it should be noted that when the infrared generator cover 1 is a flat plate structure, the partitioned chamber 32 can also be set as a flat plate (as shown in Figure 40).

[0108] As shown in Figure 3, in this embodiment, two layered plates 34 are provided, which divide the air preheating chamber 3 into three partitioned chambers 35, i.e., the number of partitioned chambers 35 is odd. The two layered plates 34 are, from the inside out, the first layered plate 341 and the second layered plate 342, and the three partitioned chambers 35 are, from the inside out, the first partitioned chamber 351, the second partitioned chamber 352 and the third partitioned chamber 353. An air intake channel 31 is provided at the bottom of the third partition cavity 353. Several second connecting holes 3421 connecting the second partition cavity 352 and the third partition cavity 353 are provided at the top of the second layer plate 342. Several first connecting holes 3411 connecting the first partition cavity 351 and the second partition cavity 352 are provided at the bottom of the first layer plate 341. The airflow path is as follows: air first enters the third partition cavity 353 through the air intake channel 31, flows upwards in the third partition cavity 353, then enters the second partition cavity 352 through the second connecting holes 3421, then flows downwards in the second partition cavity 352, then enters the first partition cavity 351 through the first connecting holes 3411, then flows in the first partition cavity 351, and finally flows out from the air outlet 32. The first partition cavity 351, the second partition cavity 352, and the third partition cavity 353 form a curved channel due to the arrangement of the first connecting holes 3411 and the second connecting holes 3421.

[0109] The multi-layered partitioned cavity 35 forms a layered space within the air preheating cavity 3. This layered space serves as the flow space for secondary air, which ultimately exits through the air outlet 32 ​​to participate in secondary combustion. The shape of this layered space closely resembles the cavity shell near the infrared generator 1, making it easier for the secondary air to approach the infrared generator 1 and exchange heat with the heated cavity shell, thus facilitating the preheating of the secondary air. A cross-section larger than the corresponding total cross-section of the air outlet 32 ​​is necessary to ensure orderly flow of secondary air. Furthermore, a larger curved channel and a smaller air outlet 32 ​​increase the air velocity at the outlet 32, which is beneficial for the secondary combustion reaction.

[0110] The infrared generating area is the region near the bottom of the pot in the infrared generating hood 1. The air preheating chamber 3 is the preheating area before the preheated air enters the infrared generating area, and it is relatively close to the infrared generating area, resulting in a higher temperature. When the air inlet cross-section of the layered space is larger than the total cross-section of the corresponding air outlet 32 ​​(the Venturi effect is more pronounced when the cross-section is 6-10 times larger), the layered plate 34 is thin and uniform in thickness. The high-temperature radiation of the infrared generating hood 1 is more uniformly distributed in the layered space, and its temperature gradient is not significantly reduced, resulting in limited heat absorption by the infrared generating hood and promoting the generation and maintenance of infrared rays. With a thinner partition cavity 35, it is closer to the infrared generating area, making it easier to maintain the high temperature and resulting in a higher preheated air temperature. In practical use, the layered plate 34 is also set to a relatively thin thickness, specifically between 0.3 mm and 1.2 mm, preferably 0.8 mm.

[0111] As shown in Figure 4, in one embodiment, one layered plate 34 is provided, and the number of partition chambers 35 is even. Air participating in secondary combustion passes through a curved channel, allowing the heat energy already transferred to the partition chambers 35 to be carried back to the secondary combustion zone. The use of two or more partition chambers 35 allows the external cold air to be gradually preheated, flowing from the relatively lower-temperature partition chambers 35 to the higher-temperature zone, gradually absorbing the conducted heat. Under the conditions of flame entrainment, the secondary air enters from the bottom, passes through the curved channel, and then descends to the air outlet 32, giving the secondary air a downward vector velocity. This vector is opposed to the flame flow direction, and the turbulence generated by this impact is beneficial to the secondary combustion reaction (as shown in Figure 4).

[0112] The partition chambers 35 work together to form a siphon structure, which reduces the load on the ejector force, ensuring that the initial velocity of the ejected secondary air is not affected. Simultaneously, it collects heat layer by layer, carrying the conducted heat back into the infrared generation area, converting it into effective heat and generating positive effects. A portion of the heat is conducted into the air preheating chamber 3, then to the partition chambers 35 and the insulation cover 2. Since the heat conduction in the multi-layered partition chambers 35 is relatively slow, even if some heat is conducted out, some will be used to preheat the combustion-supporting secondary air. This heat, carried by the combustion-supporting secondary air through the air preheating chambers 3, gradually approaches the air outlet 32 ​​and is preheated step by step, with the temperature increasing. Ultimately, it is still carried into the infrared generation area to support secondary combustion and is reabsorbed by the heating appliances.

[0113] Example 3: As shown in Figures 5 to 8, this example is similar in structure to Example 2, except that a plurality of chamber partition plates 36 are provided in the partition cavity 35 near the infrared generator hood 1. The partition plates 36 are arranged vertically along the partition cavity 35, dividing the partition cavity 35 into small air intake chambers 37. Each small air intake chamber 37 has an air inlet 371 at one end and is connected to at least one air outlet 32 ​​at the other end. The air inlet 371 of each small air intake chamber 37 is located below the air outlet 32, so that the small air intake chamber 37 forms an upwardly inclined air intake channel, so that when the air is preheated, it can automatically flow upward.

[0114] The chamber partition 36 includes, but is not limited to, being arranged horizontally (as shown in Figure 6), in a wavy pattern (as shown in Figure 7), or in a stepped pattern (as shown in Figure 8).

[0115] The partition plates 36 serve several functions: First, the walls of the partitioned air intake chambers 37 act as heat-insulating chambers, reducing heat conduction outwards. Second, they extend the flow path of the preheated air, increasing preheating time and raising the temperature of the preheated air. Third, they allow for the arrangement of the air outlet 32 ​​size in each partitioned chamber, ensuring orderly flow and reasonable distribution of preheated air (each air intake chamber corresponds to a ring of air outlets; if a ring of outlets requires a larger supply of preheated air, the corresponding outlet is enlarged, and vice versa). Fourth, when external wind blows towards the air outlet 32, it reduces the backflow and leakage of preheated air caused by external wind and other factors. Fifth, the added partition plates 36 and layered plates 34 increase the inner surface area of ​​the air preheating chamber 3, increasing the chances of contact and collision between the preheated air and the inner wall of the air preheating chamber 3, facilitating heat exchange and better preheating of the air (as shown in Figure 3). Looking at the normal direction of the cavity wall of the cavity partition plate 36, the greater the inclination angle and the more steps of the inclined cavity partition plate 36 and the more air intake chambers 37 the normal line passes through, the better the heat insulation effect and the higher the preheated air temperature.

[0116] Example 4: As shown in Figures 9 and 10, this example is similar in structure to Example 1 or Example 2, except that the air preheating chamber 3 is provided with several dividing blocks 38 arranged in the circumferential direction along the axis of the infrared generator cover 1. The dividing blocks 38 divide the air preheating chamber 3 into several preheating chambers in the circumferential direction along the axis of the infrared generator cover 1.

[0117] The dividing baffle 38 can be a spoke shape distributed along the air preheating cavity 3 (as shown in Figure 9, viewed from above), or it can be a spiral shape distributed along the air preheating cavity 3 (as shown in Figure 10, viewed from above). The dividing baffle 38 includes, but is not limited to, spoke and spiral shapes.

[0118] The spiral-shaped, spoke-shaped dividing baffle 38 divides the air preheating chamber 3 into several smaller preheating chambers. This forces the air entering the preheating chambers to flow along a curved path, thereby increasing the flow path of the preheated air. This results in a longer path and a longer flow time, allowing for more thorough heat exchange within the preheating chambers and leading to a higher preheated air temperature. Upon reaching the air outlet 32, the air is ejected tangentially, creating a certain swirling effect.

[0119] In addition, the adjacent preheating chambers are isolated from each other, and the air flow in each preheating chamber is not affected by the other preheating chambers. This makes the air flow in each preheating chamber more stable, and the preheated air flowing out of the air outlet 32 ​​is also more stable. This makes the participation in the secondary combustion of the gas more stable and improves the efficiency of the secondary combustion of the gas.

[0120] Example 5: Referring to Figures 11 and 12, this embodiment is similar in structure to Example 1, Example 2, Example 3, or Example 4, except that the side wall of the infrared generator cover 1 is provided with several protrusions 11, and the air outlet 32 ​​is provided on the protrusions 11.

[0121] The protrusions 11 are distributed on the inner side of the infrared generator cover 1, forming an undulating surface on the surface of the infrared generator cover 1. This increases the reflective area of ​​the infrared generator cover 1, increasing the chance of the cookware receiving secondary reflected radiation; it also causes the air outlet 32 ​​to collide with the gas flame, resulting in more uniform mixing, stronger turbulence, and more complete secondary combustion of the gas.

[0122] In addition, the protrusion 11 can be configured as a spiral shape corresponding to the spiral dividing block (as shown in Figure 12), so that each upward flame stream encounters the corresponding preheated air, generating a stronger swirling effect, which helps the secondary combustion of the gas to be more complete.

[0123] In addition, the infrared generator cover 1 can be configured in various forms, including flat surfaces, curved surfaces, undulating surfaces, finned surfaces, spiral raised surfaces, and irregularly shaped surfaces with grooved textures; the infrared generator cover 1 can be made of materials that easily emit or reflect infrared rays, or have an infrared reflective or emitting coating on its surface.

[0124] Various shapes of infrared generator covers 1 can increase their surface area and the number of times thermal radiation is reflected from them, allowing for maximum absorption by the cookware and thus improving thermal efficiency. Simultaneously, the high-temperature, multi-shaped infrared generator cover 1 can increase the combustion catalytic surface, promoting the combustion reaction. The increased surface area also has a certain heat storage function, which is beneficial for the combustion reaction and the heating of secondary air.

[0125] Example 6: As shown in Figures 13 to 25, this example is similar in structure to Example 1, Example 2, Example 3, Example 4, or Example 5, except that an air nozzle 12 is provided at the air outlet 32, and the air nozzle 12 is a tubular structure.

[0126] The air nozzle 12 can be a separate component or integrally formed with the infrared generator cover 1.

[0127] As shown in Figures 15 to 25, the air nozzle 12 can be a single tubular structure (as shown in Figures 17 to 25) or a branched tubular structure (as shown in Figures 15 and 16).

[0128] According to the Venturi effect, a low pressure is generated near a high-speed flowing fluid, resulting in a suction effect. The negative pressure generated by the upward flow of the combustion flame and the kinetic energy generated by the preheated air flowing upward cause the air at the air outlet to flow out automatically. This also ensures the operation of the siphon structure internally designed to absorb dissipated heat. Due to inertia, the momentum direction of the air flowing out of the tubular nozzle 12 is related to the tilt, twist, and spiral pattern of the nozzle. The ejected high-temperature air is perpendicular or obliquely opposed to the flow direction of the combustion flame, significantly improving the convective thermal reaction between the high-temperature air and the flame. The irregular cross-section and shape of the air outlet 32 ​​further optimize the combustion reaction under this thermal convection condition.

[0129] The branches of the branched tubular nozzle structure are derived from a single tube, presenting a tree-like (as shown in Figure 15) or lotus seedpod-like (as shown in Figure 16) shape, with the air outlets of each air outlet branch remaining dispersed; the single tubular nozzle structure includes vertical (as shown in Figure 17), inclined (as shown in Figure 18), curved elongated, and spiral extended (as shown in Figure 19) shapes.

[0130] The tubular nozzle structure can extend into the air preheating chamber 3 (as shown in Figures 19 and 24), or into the infrared generation area (as shown in Figures 17, 18, and 23), or both (as shown in Figures 20 and 21). Once extended, the nozzle 12 is easily heated by the flame, thus preheating the air flowing through it. Furthermore, the spirally extended nozzle 12 can regulate the flow state of the preheated air after it is ejected, resulting in a high degree of mixing between the swirling air and the flame, leading to a rapid combustion reaction.

[0131] When the spiral-shaped tubular nozzle structure acts as the preheating body, it becomes the preheating body and no longer requires a large number of air preheating chambers 3 for preheating. The air preheating chambers 3 are reduced in size and weakened, and play the role of collecting heat through the flowing secondary air and returning it to the infrared generation part.

[0132] When the tubular nozzle structure extends both into the air preheating chamber 3 and into the infrared generation area, the air outlet of the infrared generation area is enveloped by the high-temperature fuel mixture. After the high-temperature air from air outlet 32 ​​is ejected, the area near air outlet 32 ​​reacts violently, becoming infrared first, further promoting the temperature rise of the preheated air and possessing a strong fuel combustion capacity. Simultaneously, the space between the tubular nozzle structures becomes a channel for the fuel mixture to be discharged upwards, and this channel also provides space for the preheating of the tubular nozzle structure. The secondary combustion reaction area shifts upwards due to the extension of the tubular nozzle structure, becoming closer to the bottom of the heated appliance, thus improving thermal efficiency. This layout avoids the situation where some existing energy-saving covers are placed too far from the bottom of the heated appliance to ensure smooth fuel mixture discharge, resulting in low heating efficiency. At the same time, the extension of the tubular nozzle structure provides a channel for flue gas discharge; it also avoids the situation where some existing energy-saving covers are placed too close to the bottom of the pot to improve thermal efficiency, resulting in narrow flue gas discharge space, insufficient combustion reaction, and potentially safety accidents.

[0133] When the curved, elongated, or spirally extended nozzle structure serves as the preheating body, the air preheating chamber 3 is reduced in size and weakened; the nozzle 12 is manufactured or disassembled from the air preheating chamber 3 body; the cross-section of the tubular nozzle structure at the air outlet 32 ​​includes circular, elliptical, polygonal, and irregular shapes; the air outlet of the nozzle 12 includes flat cut, oblique cut (as shown in Figure 21), toothed (as shown in Figure 23), and irregular shapes.

[0134] The air outlet of the nozzle 12 is set in different shapes so that the air velocity direction ejected from the nozzle 12 is obliquely, perpendicularly, or opposite to the flow direction of the gas flame, thereby enhancing the mixing and convection of high-temperature air and secondary gas and improving combustion efficiency. The various forms of the tubular structure of the nozzle 12 can meet the requirements of heat radiation and heat convection under different working conditions.

[0135] The tubular structure of the air nozzle 12 includes a shape with a uniform cross-sectional diameter, or a shape with an inlet cross-sectional area larger than the outlet cross-sectional area (as shown in Figure 24).

[0136] The tubular structure of this invention provides high-temperature air. Under the pressure of the heated appliance, the flame of primary combustion is forced to flow through the infrared emission area. Upon encountering the tubular nozzle structure, a large amount of flame impacts the tube wall of the nozzle structure, causing the nozzle structure to turn red. The ejected air with a certain initial velocity has an even higher temperature. When it encounters unburned flame, a strong combustion reaction occurs. This reaction occurs after the high-temperature air rushes out of the tubular structure. The interaction of the flame pressure, the secondary combustion reaction force, and the air ejection vector force causes strong thermal convection. The high-temperature combustion reaction triggers infrared radiation.

[0137] The proportion of heat convection and heat radiation affects the heat absorption of the heated appliance differently under different conditions. If the infrared absorption capacity of the heated appliance is limited, or if heat convection is required as the primary heating method: the air preheating chamber 3 has already heated the air to a certain temperature, meeting the conditions for dissipating residual combustibles in the flame. Adjusting the airflow direction of the tubular nozzle structure will result in higher thermal efficiency. The outlet of the tubular nozzle structure does not need to extend into the infrared generation area to generate strong heat convection. At this time, heat radiation is weak, and the heated appliance mainly absorbs heat through heat convection. When heat radiation is emphasized: the outlet of the tubular nozzle structure extends into the infrared generation area, and the nozzle 12 is reddened by the flame impact, generating infrared radiation; or an infrared auxiliary generator covers the air outlet 32, and the flame and high-temperature air react near the infrared auxiliary generator, causing the infrared auxiliary generator to rapidly heat up and generate strong infrared radiation.

[0138] Example 7: As shown in Figures 26 to 29, this example is similar in structure to Example 1, Example 2, Example 3, Example 4, Example 5, or Example 6, except that an infrared auxiliary generating component is provided inside the infrared generating cover 1. The infrared auxiliary generating component is located on the side of the infrared generating cover 1 away from the air preheating chamber 3; that is, the infrared auxiliary generating component is located in the infrared radiation area or the infrared generating area.

[0139] In one embodiment, the infrared auxiliary generator includes an infrared auxiliary generator cover 4 (as shown in Figure 26, 27, or 28). The infrared auxiliary generator cover 4 has a mesh structure; it can also be an irregularly shaped porous structure. The sidewalls of the infrared auxiliary generator cover 4 can be planar (as shown in Figure 26), curved (as shown in Figure 27), or corrugated (as shown in Figure 28) structures.

[0140] The metal mesh infrared auxiliary generator hood 4 is easily heated and incinerated by the flame gas. The preheated air at the air outlet 32 ​​flows upward and encounters the incinerated metal mesh, which is dispersed by the mesh openings. The flame gas flowing through it burns rapidly under the action of the incinerated metal mesh, which is rich in high-temperature combustion air, thereby improving the efficiency of secondary combustion of the gas.

[0141] In one embodiment, the infrared auxiliary generating component further includes several infrared auxiliary generating springs 41 arranged along the axial direction of the infrared generating cover 1 (as shown in Figure 29). The infrared auxiliary generating springs 41 can be provided independently or used in conjunction with the infrared auxiliary generating cover 4.

[0142] Adding an infrared auxiliary generating spring 41 inside the infrared generating cover 1 can adjust the speed and direction of the outflowing gas after combustion, resulting in a significant increase in efficiency. The thickness and spacing of the springs can be adjusted to suit different application scenarios. Adding several infrared auxiliary generating springs 41 from bottom to top after installing a metal mesh infrared auxiliary generating cover 4 can further improve combustion efficiency.

[0143] The materials used in the infrared auxiliary generator include, but are not limited to, titanium alloys, tungsten alloys, stainless steel, ceramics, composite ceramics, precious metal catalysts, transition metal catalysts, and oxide catalysts. After the addition of the mesh-like infrared auxiliary generator, the combustion reaction is similar to that of a Davy lamp. The flame is located on one side of the infrared auxiliary generator, making it difficult to enter the other side, which is preheated air at high temperature. This high-temperature air itself possesses an initial velocity that allows it to easily pass through the channel of the infrared auxiliary generator before encountering the flame. This is similar to, but different from, the mechanism of an infrared gas stove, where the combustion reaction occurs inside the infrared auxiliary generator, whereas in this invention, it occurs afterward. After using the infrared auxiliary generator, the impact of the initial velocity direction of the air outlet 32 ​​on the infrared auxiliary generator is limited, but it still has certain positive effects.

[0144] However, under ideal conditions, provided that the secondary air volume is sufficient, if the opening of the air outlet 32 ​​is kept small and dense, the infrared generator cover 1 will have the same function as the infrared auxiliary generator; however, this method makes the air outlet 32 ​​prone to clogging, and its manufacturing difficulty also increases. Therefore, the infrared auxiliary generator can be used as a medium- to long-term consumable.

[0145] Example 8: As shown in Figures 1 to 4, this example is similar in structure to Example 1, Example 2, Example 3, Example 4, Example 5, or Example 6, except that the heat insulation cover 2 is located outside the air preheating chamber 3; the heat insulation cover 2 includes a heat insulation chamber 22 wrapped by a heat insulation wall 21, the heat insulation wall 21 being made of metal, ceramic, or composite ceramic, and the heat insulation chamber 22 being constructed by evacuating a vacuum, filling it with air, filling it with foamed metal, filling it with heat insulation cotton, or filling it with other materials that block heat transmission; when the heat insulation wall 21 of the heat insulation cover 2 and the shell of the air preheating chamber 3 are made of the same material, they are integrally formed.

[0146] The goal of gas appliances is to maximize the absorption of the chemical energy of combustibles by the target heated part, i.e., to improve thermal efficiency. The thermal insulation cover 2 of this invention ensures that chemical energy is absorbed by the target heated part as much as possible, minimizing its loss to areas outside the target heated part. The thermal insulation cover 2 uses vacuum chambers, air chambers, and insulation cotton to reduce heat loss, maintain the high temperature of the preheated air, protect other parts of the gas appliance such as the tempered glass panel, and ensure the generation of infrared heat radiation and improved thermal efficiency. In addition to blocking heat from spreading outwards, the thermal insulation cover 2 further maintains the temperature of the air preheating chamber 3, laying the foundation for the subsequent ejection of high-temperature air.

[0147] When the thermal insulation cover 2 is made of foamed aluminum or other thermal insulation materials with a certain strength, it has both structural strength and thermal insulation performance. The outer shell of the air preheating chamber 3 can be replaced by it, and the two are integrated into one.

[0148] Example 9: As shown in Figures 30 and 31, this example is similar in structure to Example 1, Example 2, Example 3, Example 4, Example 5, Example 6, Example 7, or Example 8, except that it also includes a return air cavity 5, which is correspondingly arranged in close contact with the air preheating cavity 3; the top circumference of the infrared generator cover 1 is provided with a return air inlet 51 that communicates with the return air cavity 5, and the end of the return air cavity 5 away from the return air inlet 51 is provided with a return air outlet 52; the return air outlet 52 is connected to the chimney 56.

[0149] Additionally, a fire observation and pressure relief device is installed on the top of the infrared energy-saving cover. In this application, the fire observation and pressure relief device is a pressure relief groove 54, and a transparent fire observation window 53 can be installed on the pressure relief groove. The chimney 56 can be used for natural smoke exhaust, or a fan can be installed for auxiliary smoke exhaust.

[0150] In addition to ensuring that combustion gases are concentrated and expelled, preventing them from flowing into spaces accessible to the human body, chimney 56 creates negative pressure upon startup, effectively drawing in the flue gas produced during combustion. This suction prevents flame leakage from the observation and pressure relief device, instead drawing in a small amount of outside air and expelling it through the flue. The observation and pressure relief device allows observation of the gas appliance's combustion status (as shown in Figure 30) and maintains stable internal pressure, preventing sudden expansion of the combustion flame. The exhaust system utilizes natural air intake (Figure 31) or fan-assisted exhaust.

[0151] During the process of flue gas passing through return air chamber 5, the residual heat can be reabsorbed by the air in air preheating chamber 3, so that air preheating chamber 3 can recover the residual heat in flue gas.

[0152] The chimney effect created by chimney 56 can accelerate the flow rate inside the infrared energy-saving cover, promote the operation of return air chamber 5, create negative pressure in the fire observation and pressure relief device, and prevent the combustion products of the gas from being discharged into the cooking environment at close range, thus protecting the health of the cooks.

[0153] The flue gas with recovered superheat is directly discharged into the air through chimney 56, or a condenser 55 is installed inside chimney 56 to absorb heat, allowing the residual heat in the flue gas to be absorbed again before being discharged into the air. The water used for cooking is connected to the condenser 55, which can be used to heat the water, ensuring it reaches a certain temperature, accelerating cooking, and saving on gas consumption.

[0154] It should be noted that the condensate from the condensation unit 55 is acidic due to dissolved NOx. It can be neutralized with alkaline materials before discharge to reduce the direct release of NOx into the atmosphere and the resulting pollution.

[0155] Example 10: A gas appliance includes a furnace body 6, within which an infrared energy-saving cover as described in any one of Examples 1 to 9 is installed, and a burner head 7 is disposed in the middle of the infrared generator cover 1. Support feet 63 are provided at the bottom of the furnace body.

[0156] In one embodiment, as shown in Figure 32, the gas appliance is a portable gas stove. A gas cylinder compartment 61 is provided inside the stove body 6, and the gas cylinder compartment 61 contains a gas cylinder that supplies gas to the burner head 7. The portable gas stove employing an infrared energy-saving cover structure provides energy saving and wind protection, while also preventing flame leakage from heating the gas cylinder compartment 61.

[0157] In one embodiment, as shown in Figure 33, the gas appliance is an outdoor stove. The bottom of the stove body 6 is equipped with adjustable support feet 63. Outdoor stoves commonly using infrared energy-saving covers have energy-saving and windproof functions, saving on gas refills and enhancing the outdoor experience.

[0158] In one embodiment, as shown in Figure 34, the gas appliance is an integrated heat collection furnace. The furnace body 6 has an overall cylindrical structure, with a cylindrical opening 62 inside the furnace body 6. An infrared energy-saving cover is installed inside the cylindrical opening 62, and the shape of the infrared energy-saving cover is adapted to the cylindrical opening 62.

[0159] The furnace body 6 has a barrel-shaped structure with a large infrared area, providing a wide coverage of the cookware and increasing the heat absorption area of ​​the cookware. The heat-absorbing area through which the flame passes is longer, resulting in a high degree of heat exchange. The gas canister and bottom support can be stored inside the cookware, making it more portable and suitable for heating fluids in harsh outdoor environments such as extreme mountaineering.

[0160] In one embodiment, as shown in Figure 35, the gas appliance is a pancake maker. A flat pan 8 is provided on the top of the oven body 6. The pan is rotatably mounted on the top of the oven body 6, allowing it to rotate during use, thus ensuring more even heating. Additionally, a finned structure 81 is provided on the side of the pan near the infrared generator.

[0161] In one embodiment, as shown in FIG36, the gas appliance is a braising stove. A support foot 63 is provided at the bottom of the stove body 6. A gas pipe 64 communicating with the burner head 7 is provided at the bottom of the stove body 6.

[0162] In one embodiment, as shown in FIG37, the gas appliance is a gas rice cooker.

[0163] In one embodiment, as shown in Figure 38, the gas appliance is an oil-fired stove. The air preheating chamber 3 is connected to the feed fan 65, which blows air into the air preheating chamber 3. Combustible fuel, pressurized by gravity or external force, enters the oil-fired stove and is atomized into micro-droplets through an atomizing nozzle. These micro-droplets are ignited by an igniter, generating heat. This heat vaporizes subsequent atomized fuel, and combined with oxygen supplied by the fan, combustion occurs. The flame enters the infrared energy-saving hood and preheats the air in the air preheating chamber 3. The ventilated infrared energy-saving hood actively impacts the flame, causing a strong reaction and generating infrared radiation, further improving combustion and thermal efficiency. This design is suitable for commercial cooking.

[0164] In one embodiment, as shown in Figure 39, the gas appliance is an alcohol stove. Fuel alcohol, pressurized by gravity or external force, enters the fuel stove, rises into the lower part of the energy-saving cover, coils, and then connects downwards to the gas burner head. During use, a small amount of alcohol fuel is burned on the coil to preheat and vaporize the liquid alcohol inside. After startup, it can operate continuously; the flame size is controlled by controlling the flow rate of the incoming alcohol. The combustion flame of the gaseous alcohol impacts the infrared energy-saving cover, heating the air in the preheating chamber 3, and the high-temperature reaction generates infrared radiation. The flame flow continues to heat the alcohol after passing through the coil, allowing the entire alcohol stove to operate continuously.

[0165] Example 11: A gas appliance includes a furnace body, including an infrared energy-saving cover 1 as described in any of Examples 1 to 9. In this example, the infrared energy-saving cover 1 installed inside the gas appliance has a flat plate structure. Correspondingly, the infrared generator cover 1 and the air preheating chamber 3 are both configured as flat plate structures. It also includes a gas pipe 9, on which a plurality of flame outlets 91 are provided along its length.

[0166] In one embodiment, as shown in Figure 40, the gas appliance is an oven. An oven door 66 is provided on one side of the oven. An infrared energy-saving cover is provided at both the upper and lower ends of the oven's interior. The infrared generator covers 1 of both infrared energy-saving covers are inclined. The top of the inclined infrared generator cover 1 is the high end, and the bottom of the inclined infrared generator cover is the low end. A gas pipe 9 is correspondingly provided at the bottom end of each of the two infrared energy-saving covers. A flat pot 67 is provided at both the upper and lower ends of the oven. The flat pot 67 at the upper end is a mesh pot, and the pot 67 at the lower end is a sheet pot.

[0167] In one embodiment, as shown in Figure 41, the gas appliance is a barbecue grill. Two sets of infrared energy-saving covers are provided in this embodiment, located on the side walls of both sides of the barbecue grill. A flat pot 67 is provided on the side of the infrared generator cover 1 away from the air preheating chamber. In this embodiment, the flat pot 67 is a mesh pot. The gas pipe 9 is located at the bottom between the mesh pot and the infrared generator cover 1. Additionally, an oil collection tray 68 is provided at the bottom of the two infrared generator covers 1.

[0168] In one embodiment, as shown in Figures 42 and 43, the gas appliance is a teppanyaki grill with a flame cover. The teppanyaki grill includes two symmetrically arranged and tilted infrared generating covers 1, which are shaped like an upward-opening "V". The gas pipe is located at the bottom between the two infrared generating covers 1. A flat pot 67 is provided on the top of the two infrared generating covers 1 (as shown in Figure 43).

[0169] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any way. Other variations and modifications are possible without departing from the technical solutions described in the claims.

Claims

1. An infrared energy-saving cover, characterized in that, include: Infrared generator cover, and heat insulation cover set outside the infrared generator cover; an air preheating chamber is set between the heat insulation cover and the infrared generator cover; The air preheating chamber is equipped with an air intake channel that communicates with the outside air. The shape of the infrared generator cover is adapted to the bottom of the heated appliance. Several air outlets are provided through the infrared generator cover, where the heat convection and heat radiation of secondary combustion promote each other. Air enters from the air intake channel, passes through the air preheating chamber, and flows out from the air outlet, so that secondary combustion is generated in a dispersed manner along the heated appliance and close to the bottom of the heated appliance. When in use, the infrared generator is placed close to the bottom of the cookware; under the pressure of the cookware lid, the flame of the primary combustion is forced to flow through the infrared generator, heating the infrared generator and forming a secondary combustion with the air flowing out of the air outlet. The area near the bottom of the pot of the infrared generator cover is the infrared generation area. The energy released by the secondary combustion heats the infrared generation area, causing it to heat up to a red-hot state. The infrared generating area in the red-hot state produces infrared radiation, which directly acts on the bottom of the cookware.

2. The infrared energy-saving cover according to claim 1, characterized in that, The air preheating chamber is equipped with several layered plates distributed along the thickness direction, which divide the air preheating chamber into several partitioned chambers along the thickness direction; the two ends of adjacent partitioned chambers are connected in an alternating manner to form a curved channel; the partitioned chambers form a layered space in the air preheating chamber with a shape similar to that of the infrared generator cover; the partitioned chambers cooperate to form a siphon structure.

3. The infrared energy-saving cover according to claim 2, characterized in that, Several chamber partition plates are arranged in the partition cavity near the infrared generator cover. The partition plates are arranged vertically along the side wall of the partition cavity, dividing the partition cavity into small air intake chambers. Each small air intake chamber has an air intake hole at one end and is connected to at least one air outlet at the other end. The air intake hole of the small air intake chamber is located below the air outlet, so that the small air intake chamber forms an upwardly inclined air intake channel.

4. The infrared energy-saving cover according to claim 1, characterized in that, The side wall of the infrared generator is provided with several spiral protrusions, and the air outlet is located on the protrusions.

5. The infrared energy-saving cover according to claim 1 or 4, characterized in that, An air nozzle is installed at the air outlet. The air nozzle has a tubular structure and extends into the air preheating chamber and into the infrared generation area.

6. The infrared energy-saving cover according to any one of claims 1 to 4, wherein both the infrared generating cover and the air preheating chamber are annular structures.

7. The infrared energy-saving cover according to claim 6, characterized in that, The air preheating chamber is equipped with several dividing blocks arranged circumferentially along the axis of the infrared generator cover. These dividing blocks divide the air preheating chamber into several small preheating chambers along the circumferential direction of the axis of the infrared generator cover.

8. The infrared energy-saving cover according to claim 7, characterized in that, The divider is spiral-shaped.

9. The infrared energy-saving cover according to any one of claims 1 to 4, wherein the infrared generator cover has a flat plate structure.

10. The infrared energy-saving cover according to any one of claims 1 to 4, characterized in that, An infrared auxiliary generating component is provided inside the infrared generating cover. The infrared auxiliary generating component is located in the infrared generating area. The infrared auxiliary generating component includes an infrared auxiliary generating cover and several infrared auxiliary generating springs arranged along the axis of the infrared generating cover. The infrared auxiliary generating springs can be set up alone or used in conjunction with the infrared auxiliary generating cover.

11. The infrared energy-saving cover according to any one of claims 1 to 4, characterized in that, It also includes a return air cavity, which is attached to the air preheating cavity; the top circumference of the infrared generator cover is provided with a return air inlet that communicates with the return air cavity, and the end of the return air cavity away from the return air inlet is provided with a return air outlet; the return air outlet is connected to the chimney.

12. A gas appliance, characterized in that, It includes the infrared energy-saving cover as described in claim 1, 2, 3, 4, 5, 6, 7, 8, 10, or 11, and also includes a furnace head disposed in the middle of the infrared generating cover.

13. A gas appliance, characterized in that, It includes the infrared energy-saving cover as described in claim 1, 2, 3, 4, 5, 9, 10, or 11, wherein the infrared energy-saving cover has a flat structure and also includes a tubular furnace head.

14. A gas appliance according to claim 13, characterized in that, The infrared generator cover is set vertically; a mesh-like cookware is set on the side of the infrared generator cover away from the air preheating chamber; the tubular burner head is set at the bottom between the mesh-like cookware and the infrared generator cover.

15. A gas appliance according to claim 13, characterized in that, The infrared generator hood is tilted, and the tubular furnace head is located at the lower end of the infrared generator hood.

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