High-heat-efficiency full-upper-air-inlet gas stove

Abstract

The invention relates to a high-heat-efficiency full-upper-air-inlet gas stove which comprises a stove bottom shell, a burner, an outer air inlet piece, an inner air inlet piece, a stove panel, an air inlet pressure disc, an inner fire cover, an outer fire cover, an inner fire nozzle, an outer fire nozzle and other accessories, wherein the inner fire nozzle and the outer fire nozzle are arranged on a valve. A gradually-shrunk air inlet with a large lower part and a small upper part is processed below a fire hole in the outer fire cover, and the bottom surface of the furnace end outer air chamber is in a gradually-rising spiral shape, so that the resistance of an air path is small, the flame speed is high, and the heat efficiency is improved. The outer fire cover is made of aluminum alloy and polished, so that the outer fire cover is light in weight, small in thermal inertia, capable of reflecting infrared rays to improve thermal efficiency and low in manufacturing cost. A vent hole is formed in the concave side face of the air inlet pressure plate, primary air and secondary air of inner fire are led in through the vent hole, the stove bottom shell is provided with no hole and is of a full-upper air inlet structure, and the influence of opening and closing of a cabinet door is avoided. And air inlet holes with fixed areas are formed in the outer air inlet sheet and the inner air inlet sheet, so that the air inlet sheet and the inner air inlet sheet are stabilized in the optimal working state.

Description

TECHNICAL FIELD

[0001] The present application relates to a high-thermal-efficiency household gas stove with full top air inlet structure and unaffected by the opening and closing of the cabinet door. BACKGROUND

[0002] The gas stove has a history of more than 200 years, but the basic structure has not changed much. It is a large air type burner. The gas is injected into the burner pipe, mixed with primary air, transmitted to the burner, and then injected from the fire hole on the fire cover of the burner. After mixing with secondary air, it burns, and the flame is completely exposed to the air for cooking. Modern gas stoves have only improved in appearance, materials, ignition, safety, and other secondary aspects. The basic structure has not changed, and the thermal efficiency is low.

[0003] The present inventor found that there are four main reasons for low thermal efficiency after long-term research and development.

[0004] 1. Most of the existing gas stove burners are divided into inner and outer two circles of fire, known as two-circle fire stoves. The outer circle of fire holes injects flames in an upward diagonal manner, and the diameter of the outer circle of fire hole rows is about 110-120 mm. This design leads to the waste of the heating area between the inner and outer circle of flames, and the outer circle of fire is concentrated in a narrow circle. Although this burner has high thermal efficiency in flame detection, it has very low thermal efficiency when used with Chinese round-bottom frying pans, and the cooking effect is poor.

[0005] The root cause of this phenomenon is that the thermal efficiency detection standard is divorced from Chinese reality. The current national detection standard is based on international standards and uses a large flat-bottomed pan with a diameter of more than 30 cm for testing. Since the flame is close to the bottom of the pan and is injected outward, the flame speed is high, and the heat transfer coefficient is also high. Even if there is a waste of the middle part of the heating area, the proportion of the wasted area to the large pan bottom area is small, and the wasted part is actually the area with the lowest heat intensity on the pan bottom. Therefore, it has little effect on the overall thermal efficiency, making the detected thermal efficiency value high.

[0006] However, most of the cookware used at home is small cookware with a diameter of more than 20 cm, especially in China, where electric appliances are used for boiling water and cooking. Gas stoves are mainly used for frying. The amount of food cooked at home is usually small, and a large bowl of about 500 grams of food occupies only about 20 cm in diameter in the pan, and the amount of soup is even smaller, concentrated in the center of the pan bottom. In particular, the two-circle fire stove, which is the most widely used, has an upwardly curved round bottom, and the flame injected upwardly by the outer circle of fire has a contact diameter on the pan bottom of about 150 cm or more, which can only burn to the edge of the food, and even cannot burn the soup, only the small fire in the middle can burn the soup, resulting in a significant reduction in actual thermal efficiency. During the cooking process, the edge of the food is often burned, while the middle soup is not boiled. It is necessary to repeatedly open the lid and stir-fry, which not only causes a large amount of heat loss, but also prolongs the cooking time and causes gas waste, making it very difficult to cook.

[0007] There are also spiral stoves on the market, the outer circle of the flame is tangentially ejected along the circumference, and the increase in tangential velocity of the flame is useless, only the increase in the normal velocity of the flame, the thin layer of the flame, can increase the heat transfer coefficient and improve the thermal efficiency. Therefore, although the firepower is concentrated in the center, the flame is soft, the normal velocity is low, and the thermal efficiency is also low. There are also nine-head stoves in recent years, the flame is also dispersed, so the practical use of the two stoves is not high, but the fire distribution is more uniform than the two-circle stove and is better to burn.

[0008] There are also infrared stoves that have been modified to mix air only once to improve thermal efficiency, but in fact, it is not reasonable from the point of view, and there are significant defects such as fine fire holes, which cannot be cleaned after being blocked, and short service life, so it has been basically eliminated.

[0009] 2. The gas stove must waste part of the firepower to heat the fire cover, the stove head, and the pot rack at the beginning of each cooking, which we call thermal inertia. The heavier the fire cover and the stove head, the greater the thermal inertia, and the more heat is wasted. The existing fire cover is made of brass (previously made of cast iron, which is prone to rust), for example, a fire cover weighing 300 grams, when heated to a constant temperature of about 300°C, its consumption is approximately equal to the heat required to boil 80 grams of water. For a household gas stove that only cooks a bowl of food about 500 grams of water for a few minutes each time, it is a significant waste value, so the thermal inertia is of course the smaller the better.

[0010] The existing national standard does not measure the thermal inertia and the thermal efficiency of the round-bottom frying pan, but manufacturers should strive to produce gas stoves with low thermal inertia and high thermal efficiency when using round-bottom frying pans to truly benefit energy saving and emission reduction. Our own rough test method is to use the same round-bottom iron pot, start from cold state, and compare the time and gas consumption of each stove when boiling 500 grams or 1000 grams of water from room temperature to make a rough comparison of the actual thermal efficiency of various gas stoves.

[0011] 3. The flame is exposed to the air and burns, and the outside is mixed with too much air, resulting in a lot of heat loss.

[0012] 4. There is about 30% of the infrared radiation heat in the flame, most of which is wasted by radiating downward and sideways.

[0013] In 1997, the inventor discovered the first and second defects mentioned above while using a two-circle stove, and believed that a straight fire head that concentrates on the middle must be used for a round-bottom frying pan, so a thin-walled stainless steel fire cover was developed, weighing only about 80 grams. The stainless steel has poor heat conduction, so the heat loss to the stove head is also small, the thermal inertia is small, and the fire head is straight and concentrates upward. Although the straight fire head is far from the bottom of the pot and has more contact with cold air around it, the thermal efficiency is slightly lower than that of a two-circle stove, but the practical performance of the frying pan is much better than that of a general stove, and the thermal efficiency is only required to be qualified at that time, so it is popular with users.

[0014] Since 2015, the energy efficiency grade of gas stove has been determined, and the thermal efficiency of embedded first-class energy-efficient stove is 63% according to the national standard. Because of the unreasonable provision in the thermal efficiency test in the national standard for household gas stove (1996 edition): "... the initial water temperature should be room temperature plus 5℃, and the final water temperature should be the initial water temperature plus 50℃,...", here the room temperature plus 5℃ has been preheated for several minutes, which conceals the shortcomings of large thermal inertia fire cover. And in the 2007 edition, an unreasonable provision is added: "... 30K higher than the initial temperature, turn off the gas and continue to stir, and the highest temperature reached is the final temperature...". With such operation, the high thermal inertia stove continues to heat the pot after being turned off, and the thermal efficiency measured is even higher. In the 2020 edition, the method of the 1996 edition is restored, but 15 minutes of preheating is added in front, so there is no difference between stoves with different thermal inertia (actually, it would be more reasonable to use additional electric heating or ice bags to adjust the water to room temperature, and then start the test as soon as the gas is ignited, but because the amount of water tested is large, the difference between the test values of stoves with different thermal inertia is not large). Knowing that the energy efficiency grade of their own products is low and cannot compete, they voluntarily stopped producing the product.

[0015] In 2021, the inventor realized the third and fourth reasons for the low thermal efficiency of the above-mentioned gas stove and developed a "gas stove heat preservation furnace" (patent number 2021 2 1082865.9). The flame is burned in the heat preservation furnace, which controls the secondary combustion air and prevents too much cold air from contacting the flame and circulating the hot exhaust gas attached to the outer periphery of the flame in the furnace. Two is to make the infrared radiation in the furnace wall to improve the furnace temperature, thereby reducing heat loss, and to improve the low thermal inertia fire cover with thin-walled stainless steel inside and outside the fire cover. Due to manufacturing difficulties, it was not until the end of 2023 that the formal trial product was launched, and the detection thermal efficiency was improved to 74%. However, due to the large volume and clumsy appearance of the silicon aluminum insulation cotton installed in the heat preservation furnace, as well as other defects, the market recognition is not high.

[0016] Therefore, in May 2024, the inventor changed it to a gas stove that only controls gas without heat preservation, with the patent name "gas stove with gas control pot rack" and the patent application number 202421212615.6. Although the detection thermal efficiency is reduced to 69%, it is still much higher than the original 63% first-class energy efficiency, and the practical performance is also good, and the user can accept the appearance. However, there are some shortcomings such as the stainless steel burner is not easy to disassemble and clean, and the gas control pot rack is not easy to clean, and the color changes yellow over time.

[0017] Therefore, some existing household gas stoves also gradually begin to use gas control principles and improve the appearance to improve the detection efficiency. Some two-circle fire gas stoves are provided with a gas control disc on the pot foot, and the nominal detection efficiency is improved to 68%. However, in order to improve the detection efficiency, the diameter of the gas control disc is made very large, and the gap between the edge and the frying pan is too large. Cold air flows into the gap and has little effect when the frying pan is actually used. The practical frying performance is still very poor.

[0018] The flame of the spiral fire stove and the nine-head fire stove is not radially outward from the center, and the flame flow is turbulent, which cannot be improved by the gas control disc to improve the detection efficiency.

[0019] In fact, the gas control disc is also a furnace, which is called a gas control disc because it is a single layer of metal plate and has little heat preservation effect. In order to improve the heat preservation performance and improve the thermal efficiency, the present inventors have developed a "multi-layer energy-saving furnace", patent application number (202510928224.7) (202521418643.8) and "an energy-saving pot rack for round-bottom frying pans", patent application number (202510928225.1) (202521418646.1), which improves the heat preservation performance of the furnace and improves the detection efficiency, and also enables the furnace to play a role when the round-bottom frying pan is used, thereby improving the practical thermal efficiency.

[0020] Further research shows that the current gas stove can be improved in many ways, mainly because:

[0021] 1. From the above four reasons for the low actual thermal efficiency of the existing gas stove, it can be seen that when using a round-bottom frying pan, the flame must be concentrated in the central direct fire head to have high actual thermal efficiency. The original stainless steel high stand pipe burner developed by the present inventors also has the disadvantages of being difficult to clean and being troublesome to manufacture. Further research has also recognized that for the upward spraying flame, the method of increasing the flame speed by increasing the injection speed of the gas can be used to further improve the thermal efficiency.

[0022] 2. The primary air and the secondary air of the existing embedded gas stove are previously supplied from the bottom of the stove shell in the cabinet. Although the national standard requires that the specification indicates that a 100cm² ventilation hole and a louver are opened under the cabinet, in fact, because it affects the appearance and is beneficial for the entry and exit of cockroaches, users do not understand this principle and try to make the door gap as small as possible. The combustion required air is supplemented from the cabinet door gap. When the cabinet door gap is small, the flame looks normal but the co may increase significantly without being noticed, which is harmful to health in the long term, and opening and closing the cabinet door affects the flame when the fire is small.

[0023] Now many gas stoves increase the fire divider above the burner, change the middle secondary air inlet channel to the cooking surface, and the primary air inlet is still in the cabinet, which does not fundamentally solve the problem, but instead increases the complexity of the mechanism, the cost, and the resistance of the gas passage of the outer ring fire, which increases the unevenness of the outer ring fire and the middle secondary air inlet. Especially some aluminum die-casting burners, to demold, the outer gas chamber under the outer fire cover can only be made into a form with the gas outlet on one side, such as the left side, and the middle secondary air inlet can only be made on the right side to blow to the left side, so that the left side provides excessive secondary air, the oxygen content of the exhaust gas is very high, and the thermal efficiency is reduced, and vice versa, the right side flame has insufficient secondary air, the co value is greatly exceeded, and the thermal efficiency is also reduced.

[0024] 3. Now the damper of the gas stove is adjustable, and the standard gas is used for detection, and the damper is opened at the best position for detection. This creates the possibility that the user adjusts the damper himself, and the flame looks normal, but the co is greatly exceeded, similar to the case when the cabinet door is closed. Therefore, the gas stove should be made with a fixed damper in the best working state. For the user's health, the national standard should also be modified, and the damper should be fixed, not only the standard gas detection is qualified, but also the co detection is qualified when using the extreme unfavorable gas source. SUMMARY

[0025] Based on the above background technology, the purpose of the present application is to manufacture a household gas stove with the flame concentrated in the center, which is beneficial to the use of round-bottom frying pans and improves the thermal efficiency by increasing the flame speed through multiple measures, and the air inlet is on the whole cooking surface, the working state is stable, and is not affected by the opening and closing of the cabinet door. The user cannot adjust the damper himself, and the co may be seriously exceeded.

[0026] According to the above purpose, a high-thermal-efficiency full-air-inlet gas stove of the present application comprises:

[0027] a stove bottom shell;

[0028] a burner arranged on the stove bottom shell, which is composed of an inner air inlet piece, an inner injection pipe, an inner air chamber, and an outer air inlet piece, an outer injection pipe, and an outer air chamber, each of which is connected by a gas path; the inner air chamber is a vertical circular tube with an upward gas outlet; the outer air chamber is an annular air chamber composed of an outer air chamber outer ring, an outer air chamber inner ring, and an outer air chamber bottom plate, a square air inlet on the side, and an annular gas outlet upward, concentrically arranged outside the inner air chamber, and the annular space formed between them serves as an inner secondary air inlet channel; an inner fire gas nozzle and an outer fire gas nozzle on the gas valve are respectively arranged at the inner air inlet piece and the outer air inlet piece, and respectively aligned with the center of the inner injection pipe and the outer injection pipe to inject gas; an electric spark ignition needle and an automatic flameout protection thermocouple are also arranged on the burner.

[0029] A cooktop is arranged on the cooktop shell, and a cooktop hole is machined on the cooktop. A concentric fixing ring is fixed on the outer air chamber of the burner head;

[0030] An air inlet pressure disc is arranged on the burner head, and a pressure disc inner flange is fixed on the burner head. An air inlet pressure disc outer flange is arranged on the cooktop hole.

[0031] An inner fire cover is arranged on the inner air chamber outlet of the burner head.

[0032] An outer fire cover is arranged on the outer air chamber outlet of the burner head, and a plurality of fire holes are uniformly distributed on the outer fire cover. A tapered air inlet is machined on the lower surface of each fire hole.

[0033] In the high-heat-efficiency full-up air inlet gas stove described above, the fire holes on the outer fire cover are circular holes, and a tapered hole is machined on the lower surface of each fire hole. A plurality of holes are arranged in a radial direction, and then a plurality of rows are arranged along the circumference.

[0034] In the high-heat-efficiency full-up air inlet gas stove described above, the fire holes on the outer fire cover are radial slit-shaped fire holes, and a plurality of fire holes are arranged along the circumference. A tapered groove is machined on the lower surface of each fire hole.

[0035] In the high-heat-efficiency full-up air inlet gas stove described above, the outer air chamber bottom plate of the burner head is machined as a tapered spiral surface along the airflow direction, and the range is more than 270º.

[0036] In the high-heat-efficiency full-up air inlet gas stove described above, the outer ejector pipe of the burner head is divided into two sections: the first section is a general burner head ejector pipe, and the second section is a circular-to-square pipe, and the square air outlet is connected to the square air inlet of the outer air chamber.

[0037] In the high-heat-efficiency full-up air inlet gas stove described above, the outer air inlet piece of the burner head is machined with a fixed area of air inlet holes.

[0038] In the high-heat-efficiency full-up air inlet gas stove described above, the inner air inlet piece of the burner head is machined with a fixed area of air inlet holes.

[0039] In the high-heat-efficiency full-up air inlet gas stove described above, the outer fire cover is made of aluminum alloy material.

[0040] In the high-heat-efficiency full-up air inlet gas stove described above, the outer surface of the outer fire cover is polished to the natural color of aluminum.

[0041] In the high-heat-efficiency full-up air inlet gas stove described above, the side surface of the lower concave circular ring part between the air inlet pressure disc and the cooktop hole is provided with air holes, through which primary air and secondary air required by the inner fire are introduced.

[0042] As mentioned above, the high thermal efficiency full upper air intake gas stove of the present application takes a number of measures, mainly to improve the flame speed and improve the thermal efficiency of the gas stove. It is changed to full upper air intake to avoid the influence of opening and closing the cabinet door, and the inner and outer air regulating air door is removed to improve the stability and safety of the gas stove. The detailed principle is described in the following examples. BRIEF DESCRIPTION OF DRAWINGS

[0043] The embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0044] Figure 1 is a side view schematic diagram of an embodiment of the present application.

[0045] Figure 2 is a top view schematic diagram of Figure 1 , in which the lower right part is the A-A cross section in Figure 1 .

[0046] Figure 3 is a top view of an embodiment of the strip-shaped fire hole machined on the fire cap.

[0047] Figure 4 is an expanded view along a certain circular diameter B-B cross section of the strip-shaped fire cap in Figure 3 .

[0048] Figure 5 is a C-C cross-sectional enlarged view in Figure 2 , showing an embodiment schematic diagram of the burner air inlet.

[0049] Figure 6 is an embodiment schematic diagram of the present application device a multi-clad energy-saving hearth. DETAILED DESCRIPTION

[0050] The present application believes that:

[0051] 1. As known from the above, when using a frying pan, the flame should be upward and concentrated at the center of the bottom of the pan.

[0052] 2. As known from the thermal principle, the higher the flame speed, the higher the heat transfer coefficient and the higher the thermal efficiency.

[0053] 3. The jet flame speed includes the natural floating speed of the flame and the gas jet speed, but is limited by the flame separation speed and cannot be too high.

[0054] 4. The higher the flame propagation speed, the higher the flame separation speed, and when the air excess coefficient is 0.9-1, it reaches the maximum value. Therefore, to improve the flame speed, it is necessary to increase the air excess coefficient as much as possible, that is, to increase both the mixed air quantity and the gas jet speed. In addition, a high air excess coefficient reduces the amount of secondary air that needs to be driven by the flame, which also improves the flame speed.

[0055] The application adopts the following specific measures: reducing the air path resistance, the smaller the resistance, the greater the air flow of the same area of the fire hole, wherein the amount of gas is fixed, and the amount of air is increased, so as to increase the excess air coefficient and the flame speed. If the flame is generated, the total area of the fire hole is increased.

[0056] The principle of the improvement of each aspect will be introduced one by one in the following examples. Please refer to Figure 1 、 Figure 2 , which are the side view and top view of the application respectively. Among them Figure 2 the lower right part is Figure 1 A-A section in the middle of the furnace head shows the structure of the gas inlet injection part.

[0057] 1 is the stove bottom shell, which is internally provided with a gas valve, an igniter, an automatic flameout protection device and various necessary accessories such as a pot rack on the cooking surface, in addition to various related accessories described below. Since it is not related to the patent, it is not drawn.

[0058] 2 is the furnace head, which is arranged on the stove bottom shell 1 and is composed of the inner gas inlet fin 2-1, the inner injection pipe 2-2, the inner gas chamber 2-3, the outer gas inlet fin 2-4, the outer injection pipe 2-5 and the outer gas chamber 2-6, which are respectively connected by gas paths. For die-casting furnace heads, the inner and outer injection pipes and the inner and outer gas chambers are separately processed and assembled. The inner gas chamber 2-3 is a vertical circular pipe with an upward gas outlet. The outer gas chamber 2-6 is an annular gas chamber composed of an outer gas chamber outer ring 2-6-1, an outer gas chamber inner ring 2-6-2 and an outer gas chamber bottom plate 2-6-3. The square gas inlet 2-6-4 is on the side, and the annular gas outlet is upward and concentrically arranged outside the inner gas chamber 2-3, and the annular space 2-7 formed between them serves as a channel for the second inner air inlet.

[0059] The inner fire gas nozzle 3 and the outer fire gas nozzle 4 on the gas valve are respectively arranged on the inner gas inlet fin 2-1 and the outer gas inlet fin 2-4, and are respectively aligned with the centers of the inner injection pipe 2-2 and the outer injection pipe 2-5 to inject gas. The furnace head is also provided with an electric spark ignition needle 5 and a thermocouple 6 for automatic flameout protection.

[0060] The cooking surface plate 7 is arranged on the stove bottom shell 1, and a hole is processed on it, which is sleeved outside the outer gas chamber outer ring 2-6-1 of the furnace head.

[0061] The gas inlet pressure disc 8 is a concave circular ring disc, which has a pressure disc inner flange 8-1 fixed on the furnace head 2 and a pressure disc outer flange 8-2 pressed on the hole edge of the cooking surface 7 and positioned concentrically, and a gas passage 8-3 is opened on the side.

[0062] The inner fire cover 9 is arranged on the outlet of the inner gas chamber 2-3 of the furnace head.

[0063] The outer fire cover 10 is arranged on the outlet of the outer air chamber 2-6, and the upper surface thereof is formed as a concave annular surface. The circular fire holes 10-1 on the outer fire cover are uniformly distributed on the surface of the outer fire cover, and each of the fire holes is formed as a conical tapering inward air inlet 10-2 with a large lower diameter and a small upper diameter. In this way, the inlet area is increased, the speed can be reduced by several times, and the inlet resistance coefficient of the fire hole is greatly reduced (estimated to be 0.1, while the existing stove has a sharp right-angled edge on the air inlet hole, and the air inlet resistance coefficient is as high as 0.5). The tapering air inlet 10-2 can be processed during die casting, and then the laser is used to punch the hole 10-1.

[0064] The fire holes 10-1 on the fire cover are arranged in a radial row, and then several rows are arranged along the circumference. In this way, it is beneficial for the gas to be supplemented with secondary air from the gap when it is not burning after being sprayed from the fire hole.

[0065] Referring to Figure 3 and Figure 4 , the fire holes can be processed as strip-shaped fire holes, and several rows are arranged along the circumference as shown in Figure 3 , the outer fire cover 10A and the fire holes 10A-1. Figure 4 The cross-sectional structure of the fire hole is shown in an enlarged view, and the lower inlet is a small-angle groove surface 10A-2 with a large lower diameter and a small upper diameter.

[0066] Figure 1 Figure 2 The outer air chamber bottom plate 2-6-3 of the stove head 2 is processed with a gradually rising spiral shape along the direction of the air flow, and the range is more than 270°. The air inlet 2-6-4 is square. The outer ejector pipe 2-5 of the stove head 2 is divided into two sections: the first section is a general stove head ejector pipe 2-5-1; and the second section is a circular-to-square pipe 2-5-2. Since the area is gradually expanded, it also has an ejector function, and the square outlet is connected to the square inlet 2-6-4 of the outer air chamber.

[0067] The square air outlet is designed to reduce the wind speed, which is only used to send gas to each fire hole. If the speed is too high, not only the dynamic pressure is consumed, but also the resistance in the channel is large and the static pressure is wasted. This design mixes the gas with primary air, and sends the gas upward while rotating in the spacious and non-tortuous outer air chamber, so that the resistance loss is much lower than that of the general stove structure.

[0068] Referring to Figure 5 , it is Figure 2The middle C-C section view enlarged view. The outer air inlet piece 2-4 of the burner head is not provided with an air adjusting door, and its wind blocking area is as small as possible, only for positioning the outer fire gas nozzle 4, and the air inlet area 2-4-1 is as large as possible to reduce the air inlet air path resistance and improve the efficiency of the ejector. The inner air inlet piece 2-1 of the burner head is also not provided with an air adjusting door, and a fixed hole 2-1-1 is adopted, which can be connected with the outer air inlet piece 2-4. The design is to prevent the user from adjusting the air door to change the optimal working state of the stove, even the state of the co value seriously exceeding the standard. If the flame is abnormal, it means that there is a fault somewhere, and professional maintenance should be called.

[0069] The outer fire cover 10 or 10A is made of aluminum alloy material, and the outer surface is polished to be the original color of metal aluminum.

[0070] When artificial gas was used before, the flame propagation speed was fast, and it was easy to backfire in the burner head, so the burner head had to be made of cast iron, and the fire cover could only be made of iron or brass. Now artificial gas has been eliminated, and natural gas and liquefied gas cannot backfire, so now the burner head made of aluminum alloy has been used, but the fire cover is still made of brass. People misunderstand that the melting point of aluminum alloy is only 660℃, and it cannot be used as a fire cover. In fact, the fire cover is below the flame, and after the air is mixed once, the speed of the gas after being sprayed out of the nozzle is high and cannot burn. Only after mixing the secondary air and reducing the speed, the gas can burn. The flame is about 2mm away from the nozzle, and cannot contact the edge of the nozzle to heat the fire cover. The temperature of the fire cover rises because there is part of the downward infrared radiation heat in the flame. The proportion of infrared heat in the gas flame is originally small, about 30% of the total heat. Moreover, part of it radiates upward to heat the pot bottom, part of it radiates to the surrounding to waste, only a small part of it radiates downward to the fire cover to heat and make the fire cover heat up. After the fire cover heats up, it also starts to dissipate heat, part of which recovers heat from the heated secondary air and the combustion gas in the nozzle, part of which radiates upward to heat the pot bottom, part of which radiates to the surrounding to waste, and part of which radiates downward to the burner head to dissipate heat. The higher the temperature of the fire cover, the more heat is dissipated. When the heat absorbed and the heat dissipated are equal, it reaches a balance, and stabilizes at a fixed temperature, which is generally only about 300℃, far lower than the melting point of 660℃ of aluminum alloy. It is generally believed that the long-term use temperature of aluminum alloy should be lower than 200℃, which refers to the decrease of its mechanical strength, like the annealing of steel, which becomes soft. The fire cover is not a force component, and tests show that the working temperature of the aluminum alloy fire cover of the design is only about 250℃, which is completely not a problem. The aluminum alloy fire cover has 5 advantages:

[0071] 1. Light specific gravity, only 1 / 3 of brass, which can greatly reduce the thermal inertia of the gas stove, heat up fast, and is beneficial to household gas stoves.

[0072] 2. Low price, only half of brass, so the price of the same volume of aluminum alloy fire cover is only 1 / 6 of the brass fire cover, and its melting point is low, the cost of die casting processing is also low, which can reduce the production cost.

[0073] 3. The polished surface of the high-purity aluminum alloy has excellent optical performance in the full spectrum, especially in the infrared, with reflectivity of over 85% and emissivity of below 15%. The polished surface of the outer fire cover reflects infrared rays and absorbs less heat, thus improving thermal efficiency and reducing the temperature of the fire cover.

[0074] 4. The aluminum alloy surface has a layer of natural transparent oxide film for protection. The color and optical performance do not change after repeated heating and cooling as long as the temperature is not close to the melting point.

[0075] 5. The long wavelength of infrared rays requires low roughness of the reflective surface. The surface of the outer fire cover is generally not dirty. Even if the surface is dirty, the user can restore the performance by wiping it with a steel wool cloth to reveal the original color of the metal aluminum. Even if the user does not clean it for a long time, the thermal efficiency is slightly lower and the temperature of the fire cover is slightly higher.

[0076] The stove head 2 still uses the traditional form of lower air inlet in the passage 2-7 between the inner and outer fire covers for the inlet of secondary air. The outer shape of the air inlet pressure disc 8 is a concave circular ring disc, with an inner flange 8-1 fixed on the stove head and an outer flange 8-2 pressed on the hole edge of the cooking surface 7. The side of the lower concave circular ring part has air holes 8-3, through which stable primary air and the required secondary air between the inner and outer fires can be introduced. The bottom shell 1 can have no holes or only a small number of holes, and the working point of the stove is not affected by the gap of the cabinet door.

[0077] See also Figure 6, is the schematic diagram of the multi-cladding energy-saving furnace chamber of the device, with several small improvements. Among them 11 is the outer chamber, which is processed with several feet below and is sleeved with silica gel pad 11-1, forming several air inlets 11-2. 12 is the inner chamber, which is integrally processed with a positioning sleeve 12-1, which is sleeved on the outer air chamber outer ring 2-6-1 to position and seal air, and is processed with a plurality of outer air inlets 12-2 on it. The position of the hole is as high as possible to enter the higher temperature secondary air recovery heat. Adjust the size and number of holes to adjust the amount of secondary air inlet, and fix it after reaching the best effect. The inner chamber 12 is made of pure aluminum plate and polished to the color of aluminum, plus the upper aluminum foil basin 13 and the lower aluminum foil basin 14, which greatly reduces the heat radiation to the outside. The lower aluminum foil basin 14 divides the space of the inner and outer chambers into two, also reducing the convection heat dissipation of the air, so the heat preservation and energy saving effect is better. 15 is the fire cover ring, and 16 is the pot rack. The upper aluminum foil basin 13 has a great effect: 1. It can reflect the waste infrared heat to heat the pot bottom to improve the heat efficiency; 2. The weight is very light, although it is attached to the lower aluminum foil basin, but only a few points of contact, the thermal resistance is very large, and it can quickly rise to a very high temperature, which can keep the circulating combustion exhaust gas outside the flame in the inner chamber at a high temperature, which is fast and hot. It is very beneficial to short-time frying; 3. It protects the inner chamber 12, which is still bright and new after repeated heating. If it is occasionally splashed with contaminated soup, etc., it will be discarded and replaced with a new one due to its low price, otherwise it will be difficult to clean the dry and hard surface of the high-temperature inner chamber 12.

Claims

1. A high thermal efficiency full updraft gas stove, characterized in that, It comprises: a bottom shell; a burner head arranged on the bottom shell, comprising inner air inlet blades, inner ejector pipes, inner air chambers, outer air inlet blades, outer ejector pipes and outer air chambers which are in communication with each other; the inner air chamber is a vertical circular tube with an air outlet upward; the outer air chamber is an annular air chamber composed of an outer air chamber outer ring, an outer air chamber inner ring and an outer air chamber bottom plate, the square air inlet of the outer air chamber is on the side, the annular air outlet is upward and concentrically arranged outside the inner air chamber, and the annular space formed between them serves as an inner secondary air inlet channel; the inner fire gas nozzle and the outer fire gas nozzle with gas valves are respectively arranged at the inner air inlet blades and the outer air inlet blades, and respectively inject gas into the center of the inner ejector pipe and the outer ejector pipe; the burner head is also provided with an electric spark ignition needle and an automatic flameout protection thermocouple; a cooking panel arranged on the bottom shell, which is provided with cooking panel holes and is concentrically fixed outside the outer air chamber of the burner head; an air inlet pressure disc which is concave and circular in shape, has a pressure disc inner flange fixed on the burner head and a pressure disc outer flange pressed on the edge of the cooking panel hole; an inner fire cover arranged on the outlet of the inner air chamber of the burner head; and an outer fire cover arranged on the outlet of the outer air chamber of the burner head, which is provided with a plurality of fire holes on the upper surface, and each fire hole is provided with a tapered air inlet with a large lower part and a small upper part.

2. The high thermal efficiency, all-updraft gas range as claimed in claim 1 wherein, The fire holes on the outer fire cover are circular holes, which are processed into conical holes with a large lower part and a small upper part, and are divided into multiple groups, each group is arranged in a radial direction, and multiple groups are arranged along the circumference.

3. The high thermal efficiency, all-updraft gas range as claimed in claim 1 wherein, The fire holes on the outer fire cover are radial slit-shaped fire holes, which are processed into a groove surface with a large lower part and a small upper part, and multiple fire holes are arranged along the circumference.

4. The high thermal efficiency, all-updraft gas range of claim 1, wherein, The outer air chamber bottom plate of the burner head is processed into a gradually rising spiral surface along the direction of the air flow, and the range is more than 270º.

5. The high thermal efficiency, all-updraft gas range as claimed in claim 1 wherein, The outer ejector pipe of the burner head is divided into two sections: the first section is a general burner head ejector pipe; the second section is a circular-to-square pipe, and the square air outlet is connected to the square air inlet of the outer air chamber.

6. The high thermal efficiency, all-updraft gas burner of claim 1, wherein, The outer air inlet blade of the burner head is processed with a fixed area of vent holes.

7. The high thermal efficiency, all-updraft gas burner of claim 1, wherein, The inner air inlet blade of the burner head is processed with a fixed area of vent holes.

8. The high thermal efficiency, all-updraft gas burner of claim 1, wherein, The outer fire cover is made of aluminum alloy material.

9. The high thermal efficiency, all-updraft gas stove, as recited in claim 1 and 8, characterized by, The outer surface of the outer fire cover is polished to the natural color of aluminum.

10. The high thermal efficiency, all-updraft gas burner of claim 1, wherein, The side of the lower concave circular ring part between the burner head and the cooking panel hole of the air inlet pressure disc is provided with vent holes, through which primary air and secondary air required for inner fire are introduced.

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