Unmanned wood stove

Abstract

To solve the problem that plastic greenhouse cultivation in winter season becomes difficult because of the price rise of heavy fuel oil and although there are scrap wood, thinned wood, bamboo, etc., as substitutions thereof, there are a lot of problems such as the difficulty of long-time combustion in an unmanned state and useless consumption of wood caused by directly exhausting much high heat or partial non-combusted gas from a chimney.SOLUTION: The above-mentioned problem may be solved by the following six items of: 1) setting a new wood combustion chamber of large capacity at an upper side of a grate; 2) setting a new combustion chamber at a lower side of the grate; 3) managing and setting a temperature about at 320°C or higher for preventing non-combusted gas generation; 4) setting a white smoke guide plate as combustion obstruction measures; 5) attaining the extension of combustion time by combustion of charcoal due to making wood into charcoal; and 6) remarkably prolonging the combustion time by collecting high-temperature waste heat and effectively utilizing indoor heating using a rocket stove, thereby deploying an unmanned wood stove for which it is not necessary to care of wood supply and which provides excellent heating effects.SELECTED DRAWING: None

Description

[Technical field]

[0001] This invention is a new wood stove that will continue to burn unmanned as long as there is firewood (charcoal). [Background technology]

[0002] The purpose of this development is to develop an unmanned wood stove that can use construction waste, thinned wood, bamboo, etc. as fuel to substantially reduce fuel costs due to the rising cost of heavy fuel oil currently used to heat greenhouses during the winter, while at the same time allowing the fire to continue burning unattended as long as there is a large amount of stored firewood (charcoal), providing heating for long periods of time during the night, and furthermore, since the high heat from the primary combustion is continually emitted directly from the chimney, resulting in a lot of fuel waste, it is necessary to develop an unmanned wood stove that can utilize this exhaust heat. Summary of the Invention [Problem to be solved by the invention]

[0003] Existing wood stoves have the following six issues that need to be addressed: 1) The amount of firewood put in is small, the combustion efficiency is poor, and the burning time is short. 2) The hot exhaust gas from the primary combustion is discharged directly from the chimney, resulting in a lot of fuel being wasted without being utilized. 3) Some of the unburned gas is also discharged directly from the chimney, eliminating fuel waste and requiring clean exhaust gases. 4) There is a demand for wood stoves with a new combustion structure that can completely burn fuels such as inexpensive construction waste, thinning materials, and bamboo. 5) A wood stove where the heat can be easily adjusted by adjusting the amount of air. 6) There is a demand for a new wood stove that has a simple combustion structure, is easy to manufacture, is lightweight, and is easy to use.

[0004] In response to the six issues above, the following six new combustion function measures have been implemented to resolve the issues with existing wood stoves. In particular, by utilizing the rocket stove's excellent combustion function, it has come closer to practical use. 1) A large-capacity chamber for storing new firewood is located above the grate. Existing wood stoves continue to burn by gradually adding small amounts of firewood, and the upper part of the grate serves as the combustion chamber, but this unmanned wood stove is a new wood stove that combines a primary combustion stove and a rocket stove, which can be used to store large amounts of firewood, which is charcoalized and continues to burn. 2) Set the new combustion chamber below the grate. In existing wood stoves, the underside of the grate is an air chamber and ash collecting surface, but in this new combustion chamber, the entire upper side of the grate is a chamber for storing high-temperature firewood, with the combustion chamber below and a high-temperature ash tray below that, and a high-temperature secondary combustion tube on the side.There is also an air intake window on the underside of one of the grates, and the strong suction caused by the high temperature of the secondary combustion tube constantly supplies fresh air to the new combustion chamber, keeping it in a high-temperature state. 3) To prevent the generation of unburned gas, the initial temperature is kept high (approximately 320°C or higher). This unmanned wood stove burns and dries a large amount of firewood at the same time, which can cause unburned gas to be generated due to a drop in combustion temperature. However, this wood stove uses a new combustion method that burns at a high temperature of over 320°C at the beginning of combustion, which brings the fire closer to complete combustion and prevents the generation of unburned gas. Prevention of unburned gas generation (see pages 12 and 13) Comparison tests of initial combustion temperatures of approximately 200°C and high-temperature combustion of over 320°C showed that with high-temperature combustion, the burning time was extended from approximately 7 hours to approximately 9 hours. Conversely, when the combustion temperature was low, unburned gas burned in the rocket stove's secondary combustion tube, the top plate temperature became higher than the primary combustion stove temperature, and the burning time was also shorter. By comparing the initial high temperature control of 320°C or higher and the top plate temperature of the rocket stove, it was confirmed that the generation of unburned gas was prevented. 4) White smoke guide plates are installed to prevent combustion interference. During the initial combustion process, a large amount of firewood is burned at high temperatures at the same time, which generates a large amount of white smoke (mainly water vapor and unburned gas) that fills the air and interferes with the combustion at the bottom of the firewood.As a countermeasure, a white smoke guide plate is used to guide the smoke to the secondary combustion tube, eliminating any interference with combustion.This wood stove burns strongly, prevents the generation of unburned gas, and emits clean exhaust gases. 5) By carbonizing firewood and burning the charcoal, the burning time can be extended. Existing wood stoves continuously burn by gradually adding small amounts of firewood and burning green wood, but this unmanned wood stove continuously burns by adding a large amount of firewood on top of the remaining charcoal in an enclosed firewood storage chamber, and the firewood on top is immediately carbonized at high temperatures, creating charcoal as it burns.It continues to burn without going out until there is more charcoal left, and it is a wood stove with a new combustion method that means there is no need to worry about adding firewood.Furthermore, the firepower of this stove is related to the burning area, and the burning time is related to the height of the firewood (charcoal). 6) Recover high-temperature exhaust heat using a rocket stove. Conventionally, the high heat from the chimney was directly discharged to the outside during the primary combustion, but this new stove absorbs the high heat exhaust gas generated during the primary combustion with the strong suction of the rocket stove's secondary combustion tube, recovers most of the high heat through radiation and convection within the stove, and uses all of the heat from the primary combustion for indoor heating without waste. This new wood stove with two high-temperature stoves has a significantly superior heating effect. Effects of the invention

[0005] (1) Effects of the newly developed unmanned wood stove A large amount of firewood is put into the stove at once, sealed with the lid, and burned.The firewood is carbonized and the charcoal accumulates.As long as there is charcoal, it can continue to burn for a long time even when unmanned.Furthermore, the high heat emitted from the primary combustion chamber is absorbed into the rocket stove, and most of this high heat is used for indoor heating through radiation and convection, providing significantly superior heating effect, extending the burning time, and eliminating the need to worry about replenishment of firewood.This is an unmanned wood stove with an excellent combustion structure. (2) Test results As a result of various tests, the following seven effects were confirmed. (See pages 12 and 13) (The wood stove for the combustion test was made from a commercially available 200L iron drum.) In particular, the new wood stove can burn steadily for long periods of time unmanned, which is an issue with current wood stoves, and the rocket stove's excellent heat recovery eliminates the high-temperature exhaust gases that are emitted from the chimney, which wastes a lot of fuel.The effectiveness of this unmanned wood stove has been confirmed, as it can be used for high-temperature indoor heating. 1) Five bundles of firewood were put into the primary combustion stove, and it continued to burn for 9 hours without any human presence, as long as there was charcoal. (Stove storage, can hold 10 bundles of firewood) (Firewood is a bundle of commercially available hardwood, approximately 20 cm in outer diameter, 36 cm in height) 2) Seven bundles of firewood were put into the primary combustion stove, and it continued to burn for 12 hours without any human presence, as long as there was charcoal. 3) The combustion chamber temperature was also maintained at a high average of 358°C and continued to burn. 4) Furthermore, the temperature of the top plate of the primary combustion chamber was maintained at an average of 273°C due to the high heat from the stove, and the fire continued to burn. 5) In addition, with current stoves, the high-temperature smoke from the primary combustion is discharged directly from the chimney, but with a rocket stove, this exhaust heat is absorbed and as it travels downwards from the top, most of the high heat is recovered through radiation and convection. The primary combustion temperature, approximately 358°C, is recovered inside the rocket stove and used for indoor heating. The chimney temperature at the end drops to around 50°C, and more than 80% of the heat is recovered. With excellent heat recovery efficiency, all of the heat produced can be used for indoor heating, making this an unmanned wood stove with significantly superior heating effects. 6) Furthermore, the temperature of the top plate, 224°C, can be used as stove heat for indoor heating, and the rocket stove's excellent heat recovery function can significantly reduce the amount of firewood used. 7) This unmanned wood stove has an outstanding heating effect as two stoves, with a combined heat of 497°C from the two stove tops and additional indoor heating provided by the recovered exhaust heat from the rocket stove. (3) Identifying 6 issues with current stoves and solutions The new combustion features described below allow for long burning times, no high temperature exhaust heat from the chimney, and excellent combustion and heat recovery efficiency make this an unmanned wood stove with excellent heating properties. 1) The amount of firewood put in is small, the combustion efficiency is poor, and the burning time is short. 1 A large-capacity chamber for storing new firewood is set up above the grate. 2. Install the new combustion chamber below the grate. 3. By carbonizing firewood and burning the charcoal, the burning time can be extended. 2) The hot exhaust gas from the primary combustion is discharged directly from the chimney, resulting in a lot of fuel being wasted without being utilized. 1 Rocket stoves have outstanding heat recovery efficiency, recovering the high-temperature waste heat from the primary combustion, with over 80% of that being utilized for indoor heating. 3) Some unburned gas is also discharged directly from the chimney, eliminating fuel waste and requiring clean exhaust gases. 1 High temperature control (approximately 320°C or higher) is set to prevent the generation of unburned gas. 2. White smoke guide plates are installed as a countermeasure against combustion interference. 4) There is a demand for wood stoves with a new combustion structure that can completely burn fuels such as inexpensive construction waste, thinned wood, and bamboo. 1. White smoke guide plates are installed as a countermeasure against combustion interference. 2. By carbonizing firewood and burning the charcoal, the burning time can be extended. 3. Set up the new combustion chamber below the grate to ensure complete combustion. 5) A wood stove where the heat can be easily adjusted by adjusting the amount of air. 1 Sliding type air vent window. 6) There is a demand for a new wood stove that has a simple combustion structure, is easy to manufacture, is lightweight, and is easy to use. 1 A wood stove with a simple combustion structure that does not require any major modifications to the existing stove structure. [Brief description of the drawings]

[0006] [Figure 1] TIFF2025019968000001.tif172136 [Diagram 2] TIFF2025019968000002.tif122115 [Diagram 3] TIFF2025019968000003.tif116135 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] (1) Initial combustion method (when stove is cold) Spread fire starter over the entire surface of the grate, place a large amount of firewood vertically on top, light it, and blow air through the fully open air intake.In about 30 minutes, the entire bottom of the firewood will be burning at a high temperature.When high-temperature burning of over 320°C is confirmed, the air intake window can be narrowed and the fire will continue to burn at this temperature. In addition, due to the high temperature of the combustion process, a large amount of white smoke is emitted during the initial combustion process, but the white smoke gradually becomes thinner, and finally the charcoal burns out completely, becoming smokeless as it burns on the surface.This is an unmanned wood stove. Furthermore, at the beginning of combustion, a large amount of firewood is stored in the firewood burner, and due to the drying caused by the high temperature combustion, a large amount of white smoke (mainly water vapor and some unburned gas) is emitted. (2) Continuous combustion method (when stove is hot) When burning smokeless charcoal, the new wood stove works by opening the lid of the supply chamber, putting in firewood, closing the lid and blowing air through the air window.The firewood is dried and carbonized at high temperatures of over 320°C, and the stove continues to burn as long as there is charcoal. In addition, when burning charcoal, the heat can be easily adjusted by narrowing the air window, and charcoal in particular has a strong heat and requires the amount of air to be narrowed. (3) Control points 1) The temperature measurement points during initial combustion are the combustion temperature at the bottom of the firewood, which is approximately 320°C or higher, and are controlled on the sides of the grate on the left and right of the air intake. (Stove thermometer) 2) The amount of air intake throttling also has a large effect on combustion time, so set it to restrict the amount of air as much as possible. 3)Safety management Keep the lid on the top of the stove closed while it is burning, and always close the air intake at the bottom when you open it. (Normally, only the bottom of the firewood burns and the top does not burn, but when the lid is opened, the flames rise suddenly, which is dangerous.) 4) Tar (wood vinegar) comes out of the chimney during initial combustion, so you will need to consider ways to collect it, especially if you are using it indoors. [Explanation of symbols] (Reference: Rocket stove book)

[0008] 1 Primary combustion stove 200L can (large capacity firewood storage) 2 Intake window (40x100) Reduce the amount of air to keep the combustion going for a long time 3 Lid for initial combustion (120 x 240) 4. A new structure in which dried wood such as waste wood, thinned wood, and bamboo are placed vertically in a large-capacity firewood storage chamber. In the first half of the initial period, combustible gas from the bottom of the firewood burns, and in the second half, the charcoal that has been charred from the firewood burns on the surface without smoke, allowing for long-term burning. A wood stove with a new combustion method. 5. New structure of white smoke exhaust guide plate (to prevent steam buildup from impeding the combustion of the bottom of the firewood) (White smoke, steam passage opening, 30×250) (steel plate thickness t0.3) 6 Primary combustion chamber lid (firewood inlet) (seals the primary combustion chamber for burning) 7 Rostrum steel bar ▲Φ▼12 (upper side is firewood storage chamber, lower side is combustion chamber) 8 Large capacity ash tray (drawer type) (The large-capacity ash tray shortens ash collection time and provides thermal insulation for the combustion chamber) 9. At the beginning of the combustion process, the entire bottom of the firewood is burned at high temperature to prevent unburned gas from being generated. (Initial combustion temperature must be above 320℃) 10 Rocket stove body, 2 x 50L cans (with built-in secondary combustion tube) (The high heat from the primary combustion chamber is recovered through radiation and convection and used for indoor heating.) 11 Secondary combustion tube (stainless steel chimney, outer diameter ▲Φ▼120) (required height 62.5~100cm) (The strong air suction force caused by high temperature combustion results in long-lasting strong combustion and the emission of white smoke.) 12 Rocket stove lid 13 Chimney (outer diameter ▲Φ▼120) (use of small diameter chimney for easy connection) Connected with tapping screws 14 Utilized as a burn tunnel (new combustion chamber). The entire underside of the grate is sealed in a narrow combustion chamber, allowing for high-temperature combustion. The new combustion chamber has an air intake window on the side, which reduces the amount of air and ensures complete combustion through high-temperature combustion at the bottom of the firewood. By preventing the generation of unburned gas, it promotes long-term high-temperature combustion. 15 Heat recovery (radiation and convection in stoves) 16. Kannuki

Claims

[Claim 1] The main new combustion functions of the newly developed stove consist of the following six characteristics: 1) A large-capacity chamber for storing new firewood is set up above the grate. This new wood stove is capable of burning for a long time. It stores a large amount of firewood above the grate of the sealed primary combustion stove, where it is charcoalized. With just one load of firewood, the stove will continue to burn unattended until there is more firewood (charcoal). 2) Set the new combustion chamber below the grate. This wood stove has a new combustion chamber capable of high temperature combustion, which is located under the grate of a sealed primary combustion stove.Since the entire periphery is sealed and in a high-temperature room, this new combustion chamber is also located in a narrow and sealed position, allowing for complete combustion to be maintained at a constant high temperature. 3) To prevent the generation of unburned gas, the initial temperature is kept high (approximately 320°C or higher). To prevent the generation of unburned gas, this wood stove ensures complete combustion by controlling the initial temperature high (approximately 320°C or higher), resulting in a clean wood stove with no unburned flue gas and no wasteful combustion. 4) White smoke guide plates are installed as a countermeasure against combustion interference. During initial combustion, a large amount of white smoke (mainly water vapor and unburned gas) is produced, which can interfere with combustion. As a countermeasure, this new wood stove is equipped with a white smoke guide plate that exhausts the smoke outside from the secondary combustion tube. 5) Extend the burning time by burning charcoal made from carbonized firewood. When the bottom of the firewood is partially burned in a sealed wood stove, the top of the firewood dries at high temperatures and charcoal is produced. This charcoal accumulates and becomes fuel in the latter half of the burn. As long as there is charcoal left and there is no one present, the firewood will continue to burn while lowering under its own weight, significantly extending the burn time.In addition, the amount of air can be adjusted to easily regulate the heat, making this a wood stove with an excellent new combustion method. 6) Recover high-temperature exhaust heat using a rocket stove. This wood stove has excellent heat recovery capabilities, as most of the heat generated by the primary combustion stove can be recovered inside the rocket stove, eliminating the need for high-temperature exhaust heat from the chimney and allowing for significant savings in firewood by using it for indoor heating.

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